JP2019203543A - Vibration isolation device - Google Patents

Abstract

To securely suppress abnormal noise caused by cavitation breaking without excessively decreasing inner diameters of pores.SOLUTION: A fluid encapsulated type vibration isolation device 1 includes a partition member 16 which partitions a fluid chamber 19 in a first attachment member 11 and encapsulating fluid L into a first fluid chamber 14 and a second fluid chamber 15, and a restriction passage 24 formed in the partition member so as to communicate the first fluid chamber and the second fluid chamber. The restriction passage includes a first communication part 26 opening to the first fluid chamber, a second communication part opening to the second fluid chamber, and a main body flow passage 25 communicating the first communication part and the second communication part. At least one of the first communication part and the second communication part includes a plurality of pores 26a, 26b penetrating the first barrier 38 facing the first fluid chamber or the second fluid chamber. The main body flow passage is provided with a flow change protrusion 41 with which liquid from the other of the first communication part and the second communication part is made to collide for changing a flow direction of the liquid. The flow change protrusion faces the first barrier in the opening direction of the pores.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vibration isolator that is applied to, for example, automobiles, industrial machines, and the like and attenuates and absorbs vibration of a vibration generating unit such as an engine.

  Conventionally, a cylindrical first mounting member connected to one of the vibration generating portion and the vibration receiving portion, and a second mounting member connected to the other, and these both mounting members are elastically connected. An elastic body, and a partition member that partitions the liquid chamber in the first mounting member in which the liquid is sealed into a first liquid chamber and a second liquid chamber, and the partition member includes the first liquid chamber and the second liquid chamber. A restriction passage communicating with the liquid chamber is formed, and the restriction passage includes a first communication portion that opens to the first liquid chamber, a second communication portion that opens to the second liquid chamber, and a first communication portion and a second communication portion. There is known a liquid-encapsulated vibration isolator having a main body channel that communicates with each other.

As this type of vibration isolator, for example, as shown in Patent Document 1 below, one of the first communication portion and the second communication portion is a first liquid chamber or a first liquid chamber facing the second liquid chamber. A configuration having a plurality of pores penetrating the barrier is known.
In this vibration isolator, even if a large load (vibration) is input and the first liquid chamber or the second liquid chamber is suddenly reduced to a negative pressure, even if bubbles are generated in the main body flow path, By passing through a plurality of fine pores, it becomes possible to finely divide and disperse them in the first liquid chamber or the second liquid chamber, and to reduce the generated abnormal noise even if cavitation collapse occurs where bubbles collapse Can be suppressed.

International Publication No. 2016/027606

By the way, it is conceivable to further reduce the inner diameter of the pores in order to reliably suppress the abnormal noise caused by the collapse of cavitation.
However, in this case, there arises a new problem that it becomes difficult to manufacture the partition member.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vibration isolator capable of reliably suppressing abnormal noise caused by cavitation collapse without excessively reducing the inner diameter of the pores. And

In order to solve the above problems, the present invention proposes the following means.
A vibration isolator according to the present invention includes a cylindrical first mounting member coupled to one of a vibration generating unit and a vibration receiving unit, a second mounting member coupled to the other, and both the mounting members. An elastic body that elastically connects the liquid chamber, and a partition member that divides the liquid chamber in the first mounting member in which the liquid is sealed into a first liquid chamber and a second liquid chamber, and the partition member A liquid-filled vibration isolator having a restriction passage communicating the first liquid chamber and the second liquid chamber, wherein the restriction passage opens to the first liquid chamber. A second communication part that opens to the second liquid chamber, and a main body channel that communicates the first communication part and the second communication part, and includes the first communication part and the second communication part. At least one includes a plurality of pores penetrating the first barrier facing the first liquid chamber or the second liquid chamber, The main body flow path is provided with a current-transforming protrusion that changes the flow direction by colliding liquid from either one of the first communication part and the second communication part, and The portion faces the first barrier in the opening direction of the pore.

According to the present invention, at the time of vibration input, both the attachment members are relatively displaced while elastically deforming the elastic body, the liquid pressure in the first liquid chamber and the second liquid chamber fluctuates, and the liquid passes through the restriction passage. An attempt is made to flow between the first liquid chamber and the second liquid chamber. At this time, the liquid flows into the restriction 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. Spill from.
Here, when the liquid flows into the first liquid chamber or the second liquid chamber from the restricting passage through the plurality of pores, each of the pores is caused to have a pressure loss by the first barrier in which these pores are formed. Since it circulates, the flow velocity of the liquid flowing into the first liquid chamber or the second liquid chamber can be suppressed. In addition, since the liquid flows through a plurality of pores instead of a single pore, it is possible to divide the liquid into a plurality of channels and reduce the flow rate of the liquid that has passed through the individual pores. Can do. Accordingly, even if a large load (vibration) is input to the vibration isolator, the liquid that has passed through the pores and has flowed into the first liquid chamber or the second liquid chamber, and the first liquid chamber or the second liquid chamber It is possible to suppress the difference in flow velocity generated between the liquid and the liquid and the generation of vortices due to the flow velocity difference and the generation of bubbles due to the vortices. Further, even if bubbles are generated not in the first liquid chamber or the second liquid chamber but in the restricted passage, the generated bubbles are caused to pass between the first liquid chamber or the second liquid by passing the liquid through the plurality of pores. It is possible to make the bubbles separate from each other in the liquid chamber, and it is possible to suppress the bubbles from joining and growing and to easily maintain the bubbles in a finely dispersed state.
As described above, the generation of bubbles itself can be suppressed, and even if bubbles are generated, the bubbles can be easily maintained in a finely dispersed state. However, it is possible to suppress the generated abnormal noise.

In particular, the main body flow path is provided with a current transformation protrusion that changes the flow direction by colliding liquid from either one of the first communication portion and the second communication portion. By causing the liquid from the side to collide with the current transformation protrusion before reaching the first barrier, a pressure loss is caused in the liquid, and the flow velocity can be reliably reduced before reaching the first barrier. it can. Thereby, even if it does not make the internal diameter of a pore too small, the abnormal noise resulting from cavitation collapse can be suppressed small reliably.
In addition, the current transformation protrusion is opposed to the first barrier in the opening direction of the pores, and is disposed at a position away from the central portion between the first communication portion side and the second communication portion side in the main body flow path. Therefore, it is possible to prevent the tuning from becoming difficult due to the provision of the current transformation protrusion in the main body flow path.

  Here, the current transformation protrusion is located at one end of the first communication portion and the second communication portion on the inner surface of the main body flow path, and is one end surface facing the other side. It may be arranged.

  In this case, since the current transformation protrusion is disposed on the one end face of the main body flow path and faces the first barrier in the opening direction of the pores, the current change protrusion has reached the vicinity of the one end face of the main body flow path. The liquid from the other side collides with the current transformation protrusion before reaching the first barrier. Therefore, even if the liquid from the other side reaches the vicinity of the one end surface of the main body flow path at a high speed by inputting a large load to the vibration isolator, the flow velocity is surely reached before reaching the first barrier. And the liquid can be diffused. Thus, when a large load is input to the vibration isolator, the liquid from the other side concentrates from the pores located near the one end surface of the main body flow passage among the plurality of pores. It is possible to prevent the liquid from flowing into the first liquid chamber or the second liquid chamber at a high speed.

  In addition, among the plurality of pores, the flow resistance of the pores facing the current transformation protrusions in the opening direction of the pores may be smaller than the flow resistance of the remaining pores.

  In this case, the flow resistance of the pore that is opposed to the current transformation protrusion in the opening direction of the pore and the liquid from the other side is difficult to reach is opposed to the current transformation protrusion in the opening direction of the pore. The flow from the other side is smaller than the flow resistance of the pores that the liquid from the other side can easily reach, so that the liquid from the other side is opposed to the plurality of pores in the opening direction of the current transformation protrusions and the pores. Regardless of whether it is present or not, it can flow evenly with little deviation.

  In addition, on the inner surface of the first barrier facing the main body channel, the ratio of the opening area of the pores to the plane area of the portion facing the current-transforming protrusion in the opening direction of the pores is the remaining It may be larger than the ratio of the opening area of the pores in the flat area of the portion.

  In this case, on the inner surface of the first barrier, the ratio of the opening area of the pores to the plane area of the portion that is opposed to the current transformation protrusion in the opening direction of the pores and is difficult for the liquid from the other side to reach is , Because it is not opposed to the current transformation protrusion in the opening direction of the pores, and is larger than the ratio of the opening area of the pores to the flat area of the portion where the liquid from the other side is easy to reach, from the other side The liquid can be made to flow uniformly into the plurality of pores with little deviation regardless of whether or not they face the current transformation protrusions in the opening direction of the pores.

  According to the present invention, even if the inner diameter of the pores is not excessively reduced, it is possible to reliably suppress abnormal noise caused by cavitation collapse.

It is a longitudinal cross-sectional view of the vibration isolator which concerns on 1st Embodiment of this invention. It is a top view of the partition member of the vibration isolator shown in FIG. FIG. 3 is a cross-sectional view taken along line AA in FIG. 2. It is a top view of the partition member of the vibration isolator which concerns on the 1st modification of 1st Embodiment of this invention. It is a longitudinal cross-sectional view of the vibration isolator which concerns on 2nd Embodiment of this invention. It is a top view of the partition member of the vibration isolator shown in FIG. FIG. 7 is a cross-sectional view taken along line B-B in FIG. 6. It is a top view of the partition member of the vibration isolator which concerns on the modification of 2nd Embodiment of this invention. It is a top view of the partition member of the vibration isolator which concerns on the 2nd modification of 1st Embodiment of this invention. It is a longitudinal cross-sectional view which shows the principal part of the partition member of the vibration isolator which concerns on the 3rd modification of 1st Embodiment of this invention.

Hereinafter, an embodiment of a vibration isolator according to the present invention will be described with reference to FIGS. 1 to 3.
As shown in FIG. 1, the vibration isolator 1 includes a cylindrical first mounting member 11 connected to one of the vibration generating unit and the vibration receiving unit, and a second mounting member 12 connected to the other, An elastic body 13 that elastically connects the first mounting member 11 and the second mounting member 12 to each other, and a liquid chamber 19 in the first mounting member 11 in which the liquid L is sealed are a main liquid chamber (first liquid chamber) described later. ) 14 and a partition member 16 that divides 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 1 viewed from the axial direction, a direction intersecting the central axis O is referred to as a radial direction, and a direction around the central axis O is referred to as a 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 disposed coaxially with the central axis O.

  When the vibration isolator 1 is mounted on, for example, an automobile, the second mounting member 12 is connected to an engine as a vibration generating unit, and the first mounting member 11 is connected to a vehicle body as a vibration receiving unit. This suppresses transmission of engine vibration to the vehicle body. In addition, the 1st attachment member 11 may be connected with a vibration generation part, and the 2nd attachment member 12 may be connected with a vibration receiving part.

  The second mounting member 12 is a columnar member extending in the axial direction, and is formed in a hemispherical shape whose lower end bulges downward. In the second mounting member 12, a flange 12 a that protrudes outward in the radial direction is formed at a portion located above the lower end portion of the hemispherical shape. A screw hole 12b extending downward from the upper end surface of the second mounting member 12 is formed, and a bolt (not shown) serving as an engine-side mounting tool is screwed into the screw hole 12b. The second mounting member 12 is disposed in 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 bonded to the inner peripheral surface of the upper portion of the first mounting member 11 and the outer peripheral surface of the lower portion of the second mounting member 12, respectively, and interposed therebetween. The upper end opening of the first mounting member 11 is closed from above. A first rubber film 13 a that covers the lower surface, outer peripheral surface, and upper surface of the flange portion 12 a is integrally formed on the upper end portion of the elastic body 13. A second rubber film 13 b that covers the inner peripheral surface of the first mounting member 11 in a liquid-tight manner is integrally formed at the lower end 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 attachment member 11 is formed in a cylindrical shape, and is connected to a vehicle body or the like as a vibration receiving portion via a bracket (not shown). The lower end opening of the first mounting member 11 is closed by the diaphragm 20.
The diaphragm 20 is made of an elastic material such as rubber or soft resin, and has a bottomed cylindrical shape. The outer peripheral surface of the diaphragm 20 is vulcanized and bonded to the inner peripheral surface of the diaphragm ring 21. The diaphragm ring 21 is fitted in the lower end portion of the first mounting member 11 via the second rubber film 13b. The diaphragm ring 21 is swaged and fixed in the lower end portion of the first mounting member 11. The upper end opening edge of each of the diaphragm 20 and the diaphragm ring 21 is in liquid-tight contact with the lower surface of the partition member 16.

And since the diaphragm 20 was attached to the 1st attachment member 11 in this way, the inside of the 1st attachment member 11 becomes the liquid chamber 19 sealed with the elastic body 13 and the diaphragm 20 liquid-tightly. . The liquid chamber 19 is filled (filled) with the liquid L.
In the illustrated example, the bottom portion of the diaphragm 20 has a shape that is deep on the outer peripheral side and shallow at the center. However, as the shape of the diaphragm 20, various conventionally known shapes can be adopted in addition to such a shape.

  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 has the lower surface 13c of the elastic body 13 as a part of the wall surface, and the second rubber film 13b and the partition member 16 that cover the elastic body 13 and the inner peripheral surface of the first mounting member 11 in a liquid-tight manner. It is an enclosed space, 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 1 having such a configuration is a compression-type device that is mounted and used so that the main liquid chamber 14 is positioned on the upper side in the vertical direction and the sub liquid chamber 15 is positioned on the lower side in the vertical direction. .

  The partition member 16 is provided with a restriction passage 24 that allows the main liquid chamber 14 and the sub liquid chamber 15 to communicate with each other. The restriction passage 24 is tuned so that resonance (liquid column resonance) occurs when, for example, a shake vibration having a frequency of around 10 Hz is input to the vibration isolator 1. As shown in FIG. 2, the restriction passage 24 includes a first communication portion 26 that opens to the main liquid chamber 14, a second communication portion 27 that opens to the auxiliary liquid chamber 15, and the first communication portion 26 and the second communication portion. 27 is provided with a main body flow path 25 communicating with 27.

The main body channel 25 includes a main channel 31 extending from one of the first communication unit 26 and the second communication unit 27 toward one side in the circumferential direction, and one end in the circumferential direction of the main channel 31. And an end chamber 34 projecting radially inward from the portion.
In the illustrated example, the main flow path 31 extends from the second communication portion 27 toward one side in the circumferential direction. The end chamber 34 and the first communication portion 26 are directly connected in the axial direction, and the end chamber 34 is an end portion of the main body flow path 25 on the first communication portion 26 side.

  The main flow path 31 is formed on the outer peripheral surface of the partition member 16. The main flow path 31 is disposed in the partition member 16 in an angle range of less than 360 ° with the central axis O as the center. In the illustrated example, the main flow path 31 is disposed in the partition member 16 in an angle range exceeding 180 ° with the central axis O as the center.

The main channel 31 is disposed coaxially with the central axis O, and is disposed on the lower side of the annular upper barrier 35 that is positioned on the upper side and the front and rear surfaces face the axial direction, and coaxial with the central axis O. The upper surface of the annular lower barrier 36 whose front and back surfaces are directed in the axial direction and the groove bottom surface 37 that connects the inner peripheral edges of the upper barrier 35 and the lower barrier 36 and faces radially outward are defined. Yes.
The upper barrier 35 faces the main liquid chamber 14. The lower barrier 36 faces the secondary liquid chamber 15, and the second communication portion 27 is configured by one opening that penetrates the lower barrier 36 in the axial direction.

The end chamber 34 has a circular shape in a plan view as viewed from the axial direction, and the central axis of the end chamber 34 extends in the axial direction. The end chamber 34 is disposed at a position away from the central axis O.
The outer communication portion 46 that connects the end chamber 34 and the main channel 31 extends linearly in the plan view. The outer communication portion 46 extends in the tangential direction of the inner peripheral surface of the end chamber 34 in the plan view. The size of the outer communication portion 46 in the circumferential direction is smaller than the inner diameter of the end chamber 34. The end chamber 34 projects to the other side in the circumferential direction of the main flow path 31 with respect to the outer communication portion 46. The sizes of the outer communication portion 46 and the end chamber 34 in the axial direction are equal to each other.

  Of the wall surfaces defining the end chamber 34, the upper wall surface positioned on the upper side and facing downward is the lower surface of the first barrier 38 whose upper surface faces the main liquid chamber 14, and is positioned on the lower side and facing upward. The lower wall surface is the upper surface of the second barrier 39 whose lower surface faces the auxiliary liquid chamber 15. The lower surface of the first barrier 38 and the upper surface of the second barrier 39 are flat surfaces extending in a direction orthogonal to the axial direction. The first barrier 38 and the second barrier 39 are in the shape of a disc disposed coaxially with the central axis of the end chamber 34.

  Here, in the present embodiment, the end face (one end face) 25a in the extending direction R from the second communication part 27 side to the first communication part 26 side of the main body flow path 25 is the first flow path in the main body flow path 25. Of the wall surface of the end chamber 34 that is the end portion on the communication portion 26 side, it is a portion that faces the outer communication portion 46 in the extending direction R. The end surface 25a of the main body flow path 25 faces the second communication portion 27 side along the extending direction R. The end surface 25a faces the liquid L from the second communication portion 27 side. The end face 25a of the main body channel 25 has a concave curve shape in the plan view. The end surface 25 a is a part of the inner peripheral surface of the end chamber 34.

  The first communication portion 26 includes a plurality of pores 26 a and 26 b that penetrate the first barrier 38 that faces the main liquid chamber 14. The pores 26a and 26b penetrate the first barrier 38 in the axial direction. That is, the opening direction of the pores 26 a and 26 b coincides with the axial direction and is orthogonal to the extending direction R of the main body channel 25. The pores 26 a and 26 b may be formed in the lower barrier 36 facing the sub liquid chamber 15 and provided in the second communication portion 27. The opening direction of the pores 26a and 26b may be a direction inclined with respect to the extending direction R of the main body flow path 25 and the axial direction.

As shown in FIG. 3, the flow path lengths of the plurality of pores 26a and 26b are equal to each other. The inner diameters of the pores 26a and 26b are the same over the entire length. Each of the plurality of pores 26a and 26b is smaller than the channel cross-sectional area of the main channel 31, and is disposed inside the end chamber 34 in a plan view viewed from the axial direction.
The sum total of the channel cross-sectional areas in each of the plurality of pores 26a and 26b may be, for example, 1.5 times to 4.0 times the minimum value of the channel cross-sectional area of the main channel 31. In the illustrated example, the channel cross-sectional area of the main channel 31 is the same over the entire length. The cross-sectional area of the pores 26a and 26b may be, for example, 25 mm ² or less, preferably 0.7 mm ² or more and 17 mm ² or less.

  An upper barrier 35 and a first barrier 38 defining a restriction passage 24 and facing the main liquid chamber 14; a lower barrier 36 defining a restriction passage 24 and facing the sub-liquid chamber 15; and Of the second barrier 39, the thickness of the first barrier 38 in which the plurality of pores 26 a and 26 b are formed is greater than the thickness of the upper barrier 35, the lower barrier 36, and the second barrier 39. The thickness of the first barrier 38 in which the plurality of pores 26a and 26b are located is the same over the entire region. The upper and lower surfaces of the first barrier 38 are flat surfaces extending in a direction orthogonal to the axial direction.

And in this embodiment, the current transformation protrusion 41 which makes the main body flow path 25 collide with the liquid L from the other one of the 1st communication part 26 and the 2nd communication part 27, and changes the flow direction. Is arranged.
In the illustrated example, the current transformation protrusion 41 collides the liquid L from the second communication portion 27 side. The current transformation protrusion 41 is disposed in the end chamber 34 of the main body flow path 25. The current transformation protrusion 41 is disposed on the end surface 25 a of the main body flow path 25. The current transformation protrusion 41 is opposed to the first barrier 38 in the axial direction. The current transformation protrusion 41 is opposed in the axial direction to a less than half portion of the first barrier 38 located on the first communication portion 26 side along the extending direction R of the main body flow path 25 with respect to the central portion thereof. doing. The current transformation projection 41 causes the liquid L from the second communication portion 27 side to collide and flow backward.

  The current transformation protrusion 41 is formed in a plate shape whose front and back faces in the axial direction. In the plan view, the outer peripheral edge of the current transformation protrusion 41 is connected to the end surface 25a of the end chamber 34 and extends along the end surface 25a, and both ends of the first arc portion 41b. And a first string portion 41c that extends linearly. The first string portion 41 c is substantially orthogonal to the extending direction R in the plan view and is substantially parallel to the outer communication portion 46. The current transformation protrusion 41 is gradually extended downward as it leaves | separates in the direction orthogonal to the 1st chord part 41c from the terminal surface 25a in the said planar view. The current transformation protrusion 41 is curved so as to gradually go downward as it goes toward the center along the direction in which the first chord 41c extends in the plan view. The current transformation protrusion 41 is a rigid body that is not deformed or displaced by the flow pressure of the liquid L flowing in the restriction passage 24.

  Among the plurality of pores 26a and 26b, the flow resistance of the pore 26a (hereinafter referred to as the opposed pore) 26a facing the current transformation protrusion 41 in the axial direction is opposed to the remaining current transformation protrusion 41 in the axial direction. It is smaller than the flow resistance of the non-perforated pores (hereinafter referred to as non-opposing pores) 26b.

  In the example shown in the figure, the non-opposing pores 26 b are opposed to the lower wall surface of the end chamber 34 (the inner surface of the main body flow path 25) in the axial direction without the current transformation protrusion 41. The opposed pore 26a is disposed in a portion of the first barrier 38 that is located closer to the first communication portion 26 along the extending direction R of the main body flow path 25 than the central portion thereof. The number of opposed pores 26a is smaller than the number of non-opposed pores 26b. The number of opposed pores 26 a is less than half of the plurality of pores 26 a and 26 b formed in the first barrier 38. The inner diameter of the opposed pore 26a is larger than the inner diameter of the non-opposed pore 26b. The channel lengths of the opposed pore 26a and the non-opposed pore 26b are equal to each other. The plurality of opposed pores 26a have the same shape and the same size. The plurality of non-opposing pores 26b have the same shape and the same size.

  The flow path length of the opposed pore 26a may be shorter than the flow path length of the non-opposed pore 26b, and the inner peripheral surface of the opposed pore 26a is made smooth, while the non-opposed pore An uneven portion may be formed on the inner peripheral surface of 26b. In addition, by appropriately adjusting at least one of the inner diameter, the channel length, and the like, the flow resistance of the opposed pore 26a can be reduced. It may be smaller than the distribution resistance.

  Here, the partition member 16 is configured by an upper member 47, an intermediate member 42, and a lower member 48 being stacked in the axial direction. Each of the upper member 47, the intermediate member 42, and the lower member 48 is formed in a plate shape whose front and back surfaces face the axial direction. The upper member 47 and the lower member 48 are each formed in a disk shape that is disposed coaxially with the central axis O. Note that the partition member 16 may be integrally formed as a whole.

The outer peripheral surface of the upper member 47 and the second arc portion 42a described later of the intermediate member 42 serve as the groove bottom surface 37. A first recess is formed on the lower surface of the upper member 47, and a second recess is formed on the upper surface of the lower member 48 at a position facing the first recess. An end chamber 34 is defined by the inner surfaces of the first recess and the second recess. The first communication portion 26 is formed in a portion of the upper member 47 where the first recess is located, and this portion serves as the first barrier 38. A portion of the lower member 48 where the second recess is located is a second barrier 39.
On the outer peripheral surface of the upper end portion of the lower member 48, an annular lower barrier 36 is formed that protrudes outward in the radial direction and in which the second communication portion 27 is formed. On the outer peripheral surface of the upper end portion of the upper member 47, an upper barrier 35 that protrudes outward in the radial direction and faces the lower barrier 36 of the lower member 48 in the axial direction is formed.

  The intermediate member 42 is disposed between the lower surface of the upper member 47 and the upper surface of the lower member 48. The entire intermediate member 42 is positioned below the bottom surface of the first recess of the upper member 47, that is, below the first barrier 38. The outer peripheral surface of the intermediate member 42 has a second arc portion 42a that forms part of the groove bottom surface 37 in the plan view, and a second chord portion that connects both ends of the second arc portion 42a and extends linearly. 42b. A part of the intermediate member 42 located in the end chamber 34 is a current transformation protrusion 41, and a part of the second chord part 42b of the intermediate member 42 located in the end chamber 34 is changed. The first chord 41c of the flow projection 41 is formed. Of the front and back surfaces of the intermediate member 42, portions other than the current transformation protrusion 41 are flat surfaces extending in a direction orthogonal to the axial direction.

  In the vibration isolator 1 having such a configuration, both attachment 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 restriction passage 24, and the liquid L in the sub liquid chamber 15 flows into the restriction passage 24. Through the main liquid chamber 14.

  As described above, according to the vibration isolator 1 according to the present embodiment, when the liquid L flows into the main liquid chamber 14 from the restriction passage 24 through the plurality of pores 26a and 26b, these pores 26a. , 26b is circulated through each of the pores 26a, 26b while being subjected to pressure loss by the first barrier 38 formed with the first barrier 38, so that the flow velocity of the liquid L flowing into the main liquid chamber 14 can be suppressed. In addition, since the liquid L flows through the plurality of pores 26a and 26b instead of the single pores 26a and 26b, the liquid L can be branched and distributed, and the individual pores 26a, 26b, The flow rate of the liquid L that has passed through 26b can be reduced. Thereby, even if a large load (vibration) is input to the vibration isolator 1, the liquid L that has flowed into the main liquid chamber 14 through the pores 26a and 26b, and the liquid L in the main liquid chamber 14 It is possible to suppress the flow velocity difference generated between the two vortices, and the generation of vortices due to the flow velocity difference and the generation of bubbles due to the vortices can be suppressed.

Even if bubbles are generated in the restriction passage 24 instead of the main liquid chamber 14, the generated bubbles are separated from each other in the main liquid chamber 14 by passing the liquid L through the plurality of pores 26 a and 26 b. It is possible to prevent the bubbles from joining and growing, and to easily maintain the bubbles in a finely dispersed state.
As described above, the generation of bubbles itself can be suppressed, and even if bubbles are generated, the bubbles can be easily maintained in a finely dispersed state. However, it is possible to suppress the generated abnormal noise.

In particular, the main body flow path 25 is provided with the current transformation protrusion 41 that collides the liquid L from the second communication portion 27 side and changes the flow direction thereof, so that the liquid from the second communication portion 27 side is disposed. By causing L to collide with the current transformation protrusion 41 before reaching the first barrier 38, a pressure loss can be caused in the liquid L.
Moreover, since the liquid L that collided with the current transformation protrusion 41 flows backward, the liquid L can be collided from the front with the liquid L flowing from the second communication portion 27 toward the current transformation protrusion 41. This is possible, and the generated pressure loss can be reliably increased.
As described above, the flow rate of the liquid L from the second communication portion 27 side can be reliably reduced before reaching the first barrier 38, and the inner diameters of the pores 26a and 26b can be reduced excessively. However, it is possible to reliably suppress the abnormal noise caused by the collapse of cavitation.

  Furthermore, the current transformation protrusion 41 is opposed to the first barrier 38 in the axial direction, and is located away from the central portion between the first communication portion 26 side and the second communication portion 27 side in the main body flow path 25. Therefore, it is possible to prevent the tuning from becoming difficult due to the provision of the current transformation protrusion 41 in the main body flow path 25.

  Further, since the current transformation protrusion 41 is disposed on the end face 25a of the main body flow path 25 and is opposed to the first barrier 38 in the axial direction, the first current reaching the vicinity of the end face 25a of the main body flow path 25 is reached. The liquid L from the second communicating portion 27 side collides with the current transformation protrusion 41 before reaching the first barrier 38. Therefore, even if the liquid L from the second communication portion 27 side reaches the vicinity of the end face 25a of the main body flow path 25 at a high speed due to the input of a large load to the vibration isolator 1, the flow velocity is reduced to the first flow rate. Before reaching the barrier 38, the liquid L can be surely reduced and the liquid L can be diffused. Thus, when a large load is input to the vibration isolator 1, the liquid L from the second communication portion 27 side is close to the end face 25a of the main body flow path 25 among the plurality of pores 26a and 26b. It is possible to prevent concentration from the positioned pores 26a and 26b and flow into the main liquid chamber 14 at high speed.

  In addition, the flow resistance of the opposed pore 26a that is opposed to the current transformation protrusion 41 in the axial direction and is difficult for the liquid L from the second communication portion 27 side to reach is opposed to the current transformation protrusion 41 in the axial direction. However, since the flow resistance of the non-facing pores 26b from which the liquid L from the second communication portion 27 side can easily reach is smaller, the liquid L from the second communication portion 27 side is supplied to the plurality of pores 26a and 26b. Regardless of whether or not it is opposed to the current transformation protrusion 41 in the axial direction, it can be made to flow evenly with little deviation.

Here, in the above-described embodiment, the flow resistance of the opposed pores 26a is made smaller than the flow resistance of the non-opposed pores 26b. However, the present invention is not limited to this, for example, as shown in FIG. In the (inner surface facing the main body flow path 25 side), the ratio of the opening area of the opposed pores 26a occupying the plane area of the portion facing the current transformation protrusion 41 in the axial direction is set as the remaining current transformation protrusion 41 and shaft. You may make it larger than the ratio of the opening area of the non-opposing pore 26b which occupies the flat area of the part which is not facing by the direction.
In the illustrated example, the non-facing fine pores 26 b are opposed to the lower wall surface of the end chamber 34 in the axial direction without the current-transforming protrusion 41. The inner diameters of the opposed pore 26a and the non-opposed pore 26b are equal to each other.

  In this case, on the lower surface of the first barrier 38, the opposed pores 26a occupy the plane area of the portion that is opposed to the current transformation protrusion 41 in the axial direction and is difficult for the liquid L from the second communication portion 27 side to reach. The ratio of the opening area is the opening area of the non-facing pores 26b that occupies the flat area of the portion where the liquid L from the second communication portion 27 side easily reaches without being opposed to the current transformation protrusion 41 in the axial direction. Since it is larger than the ratio, the liquid L from the second communication portion 27 side flows evenly into the plurality of pores 26a, 26b with little deviation regardless of whether or not it is opposed to the current transformation protrusion 41 in the axial direction. Can be made.

  In addition, the flow resistance of the opposed pore 26a is made smaller than the flow resistance of the non-opposed pore 26b, and as shown in FIG. The ratio of the opening area of the opposed pore 26a to the flat area of the facing portion is the opening area of the non-facing pore 26b that occupies the remaining flat area of the portion that is not opposed to the current transformation protrusion 41 in the axial direction. It may be larger than the ratio.

Moreover, in the said embodiment, although the structure which the current transformation protrusion 41 was arrange | positioned by the termination | terminus surface 25a was shown, it is not restricted to this, For example, as FIG. 9 shows, the inner peripheral surface of the end chamber 34 is shown. Of these, the protruding portion 34a may be disposed on the other side in the circumferential direction of the main channel 31 from the end face 25a. In the illustrated example, the projecting portion 34 a of the end chamber 34 has an arcuate shape projecting to the other side in the circumferential direction of the main flow path 31 in the plan view, and the current transformation projection 41 is the tension of the end chamber 34. It arrange | positions over the full length in the protrusion part 34a.
The first arc portion 41b of the current transformation protrusion 41 is connected to the extension portion 34a of the end chamber 34 and extends along the extension portion 34a in the plan view. The first chord portion 41c of the current transformation protrusion 41 is in contact with an end portion located on the other side in the circumferential direction of the main flow channel 31 among both circumferential end portions of the outer communication portion 46 in the plan view, and the extension It extends in the present direction R.

In the embodiment, the first recess is formed on the lower surface of the upper member 47, and the entire intermediate member 42 is positioned below the bottom surface of the first recess of the upper member 47, that is, the first barrier 38. Although not limited to this, for example, as shown in FIG. 10, the first recess is not formed on the lower surface of the upper member 47, and the portion where the first barrier 38 is located on the lower surface of the upper member 47, The current abutting protrusion 41 is brought close to the lower surface of the first barrier 38 and spaced upward from the upper surface of the second barrier 39 by making the portion that contacts and fixes the upper surface of the intermediate member 42 substantially flush with each other. You may let them.
In this case, most of the liquid flowing into the end chamber 34 from the main flow path 31 can collide with the current transformation protrusion 41 before reaching the first barrier 38, and the generated pressure loss can be more reliably ensured. Can be increased.

  Next, a second embodiment according to the present invention will be described. The basic configuration is the same as that of the first embodiment. For this reason, the same code | symbol is attached | subjected to the same structure, the description is abbreviate | omitted, and only a different point is demonstrated.

  In the current transformation protrusion 141 of the vibration isolator 2 according to the present embodiment, as shown in FIGS. 5 to 7, the liquid L from the other side of the first communication portion 126 and the second communication portion 27. Fork.

In the illustrated example, the current transformation projection 141 causes the liquid L from the second communication portion 27 side to collide and branch off. As shown in FIG. 7, the current-transformation protrusion 141 is formed by abutting the bottom surfaces of two conical bodies whose diameters are gradually reduced from the inner side toward the outer side in the axial direction. It is the structure which exhibits a rhombus shape seeing from the outside. The current transformation protrusion 141 is disposed coaxially with the central axis of the end chamber 34.
Hereinafter, in the plan view, a direction intersecting with the central axis of the end chamber 34 is referred to as an end chamber radial direction, and a direction around the central axis of the end chamber 34 is referred to as an end chamber circumferential direction.
The surface of the current transformation protrusion 141 is not in contact with the wall surface that defines the end chamber 34. In the plan view, the ratio of the flat area of the current transformation protrusion 141 occupying the end chamber 34 is about half. The current transformation protrusion 141 is a rigid body that is not deformed or displaced by the flow pressure of the liquid L flowing through the restriction passage 24.
In addition, for example, the current transformation protrusion 141 has a configuration, a columnar shape, a plate shape, or the like in which the bottom surfaces of two pyramids are brought into contact with each other and are formed in a diamond shape when viewed from the outside in the end chamber radial direction. May be.

  Of the surface of the current transformation protrusion 141, the surface that gradually extends inward in the radial direction of the end chamber as it goes downward from the central portion in the axial direction causes the liquid L from the second communication portion 27 side to flow. 141 is a branch surface 141a that is caused to collide from below and branch off. Of the surface of the current transformation protrusion 141, the surface that gradually extends inward in the end chamber radial direction as it goes upward from the central portion in the axial direction joins the liquid L branched by the branch surface 141 a to change the current. A guide surface 141b that guides the first barrier 38 through the protrusion 141 is formed. The inclination angles of the branch surface 141a and the guide surface 141b with respect to the center axis of the end chamber 34 are equal to each other.

  A connecting piece 143 that fixes the current transformation protrusion 141 to the wall surface of the end chamber 34 is disposed on the surface of the current transformation protrusion 141. A plurality of the connecting pieces 143 are arranged on the surface of the current transformation protrusion 141 at intervals in the circumferential direction of the end chamber. The connecting piece 143 fixes the current transformation protrusion 141 to the inner peripheral surface facing the inner side in the end chamber radial direction among the wall surfaces defining the end chamber 34. The connecting piece 143 is disposed at the central portion in the axial direction of the current transformation protrusion 141. The total sum of the sizes in the end chamber circumferential direction of the plurality of connecting pieces 143 is the sum of the sizes in the end chamber circumferential direction of the portion where the connecting piece 143 is not provided in the central portion in the axial direction of the current transformation protrusion 141. Smaller than. The current transformation protrusion 141 faces the outer communication part 46 without the connection piece 143 interposed therebetween.

  Among the plurality of pores 126a and 126b, the flow resistance of the opposed pore 126a that faces the current transformation protrusion 141 in the axial direction is the remaining non-opposed pore that does not face the current transformation projection 141 in the axial direction. It is greater than the flow resistance of 126b.

  In the illustrated example, the non-opposing fine hole 126b is opposed to the lower wall surface of the end chamber 34 (the inner surface of the main body flow path 25) in the axial direction without the current-transforming protrusion 141 interposed therebetween. The non-opposing pore 126b is disposed in the outer peripheral portion of the first barrier 38, and the opposing pore 126a is disposed in the central portion of the first barrier 38 that is located radially inward from the outer peripheral portion. The inner diameter of the opposed pore 126a is smaller than the inner diameter of the non-opposed pore 126b. The channel lengths of the opposing pore 126a and the non-opposing pore 126b are equal to each other. The plurality of opposed pores 126a have the same shape and the same size. The plurality of non-facing pores 126b have the same shape and the same size.

  The flow path length of the opposed pore 126a may be longer than the flow path length of the non-opposed pore 126b, and the inner peripheral surface of the non-opposed pore 126b is made smooth, while the opposed pore An uneven portion may be formed on the inner peripheral surface of 126a. In addition, by appropriately adjusting at least one of the inner diameter, the flow path length, and the like, the flow resistance of the opposed pore 126a can be reduced. It may be larger than the distribution resistance.

  The outer peripheral surface of the intermediate member 142 of the partition member 16 connects the second arc portion 142a forming a part of the groove bottom surface 37 and both ends of the second arc portion 142a in a plan view and extends linearly. The second string portion 142b. The intermediate member 142 is formed with a semicircular opening 142c that opens to the second chord portion 142b in the plan view. The inner peripheral surface of the opening 142c is a part of the inner peripheral surface of the end chamber 34. There is no. The current transformation protrusion 141 is connected to the inner peripheral surface of the opening 142c through a connecting piece 143. The front and back surfaces of the connecting piece 143 are flush with the front and back surfaces of the intermediate member 142. The connecting piece 143 and the current transformation protrusion 141 are formed integrally with the intermediate member 142.

  As described above, according to the vibration isolator 2 according to the present embodiment, the current transformation protrusion 141 that causes the liquid L from the second communication portion 27 side to collide and branch is provided in the main body flow path 25. Therefore, the liquid L from the second communication portion 27 side collides with the current transformation protrusion 141 and branches before reaching the first barrier 38, thereby causing a pressure loss in the liquid L. As a result, the flow rate of the liquid L from the second communication portion 27 side can be reliably reduced before reaching the first barrier 38, and the inner diameters of the pores 126a and 126b are not excessively reduced. However, it is possible to reliably suppress the abnormal noise caused by the collapse of cavitation.

  Moreover, since the guide surface 141b is formed in the current transformation protrusion 141, the liquid L from the 2nd communication part 27 side collides with the current transformation protrusion 141, and is made to merge by the guide surface 141b. This causes the branched liquids L to collide with each other, resulting in a pressure loss. Therefore, by allowing the liquid L from the second communication portion 27 side to pass through the current transformation protrusion 141, the flow velocity of the liquid L can be more reliably reduced before reaching the first barrier 38.

  In addition, the flow resistance of the opposed pore 126a that faces the current transformation protrusion 141 in the axial direction, passes through the current transformation protrusion 141, joins, and flows in the liquid L having a relatively large flow rate flows. Since the flow resistance of the non-facing pore 126b into which the liquid L having a relatively small flow rate does not flow is not opposed to the portion 141 in the axial direction, the liquid L from the second communication portion 27 side is allowed to flow into the plurality of pores. 126a and 126b can be made to flow evenly with little deviation regardless of whether or not they are opposed to the current transformation protrusion 141 in the axial direction.

Here, in the above-described embodiment, the flow resistance of the opposed pore 126a is larger than the flow resistance of the non-opposed pore 126b. However, the present invention is not limited to this, for example, as shown in FIG. In the (inner surface facing the main body flow path 25 side), the ratio of the opening area of the opposed pore 126a occupying the flat area of the portion facing the current transformation protrusion 141 in the axial direction is the remaining current transformation protrusion 141 and the shaft. You may make it smaller than the ratio of the opening area of the non-opposing pore 126b which occupies the plane area of the part which is not facing by the direction.
In the illustrated example, the non-opposing fine hole 126b is opposed to the lower wall surface of the end chamber 34 in the axial direction without passing through the current-transforming protrusion 141. The inner diameters of the opposed pore 126a and the non-opposed pore 126b are equal to each other.

  In this case, the lower surface of the first barrier 38 is opposed to the current transformation protrusion 141 in the axial direction, passes through the current transformation protrusion 141, merges, and the flat portion of the portion where the liquid L having a relatively large flow rate is guided. The ratio of the opening area of the opposed pore 126a to the area is not opposed to the current transformation protrusion 141 in the axial direction, and the non-facing pore 126b occupies the flat area of the portion where the liquid L having a relatively small flow rate is guided. Therefore, the liquid L from the second communication portion 27 side is biased regardless of whether or not it faces the plurality of pores 126a and 126b in the axial direction of the current transformation protrusion 141. It can be made to flow evenly with a small amount.

In addition, the flow resistance of the opposed pore 126a is made larger than the flow resistance of the non-opposed pore 126b, and as shown in FIG. The ratio of the opening area of the opposed pore 126a to the flat area of the opposing portion is the opening area of the non-facing pore 126b that occupies the remaining flat area of the portion that is not opposed to the current transformation protrusion 141 in the axial direction. You may make it smaller than a ratio.
The current transformation protrusion 141 may be close to the lower surface of the first barrier 38 and spaced upward from the upper surface of the second barrier 39.
In this case, most of the liquid flowing into the end chamber 34 from the main flow path 31 can collide with the current transformation protrusion 141 before reaching the first barrier 38, and the generated pressure loss is more reliably ensured. Can be increased.

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

For example, in the above-described embodiment, the current transformation protrusions 41 and 141 are disposed in the end chamber 34 of the main body flow path 25, but may be disposed in the main flow path 31 or the outer communication portion 46. , 141 may cause the liquid L from the first communication portion 26, 126 side to collide and change the flow direction thereof.
Moreover, the current transformation protrusions 41 and 141 may change the flow direction by causing the liquid L to collide, and may not cause the liquid L to reversely flow or branch off.
Moreover, you may employ | adopt the structure in which both the 1st communication parts 26 and 126 and the 2nd communication part 27 have pore 26a, 26b, 126a, 126b.
Moreover, although the structure which makes the partition member 16 1 round as the main flow path 31 was shown, the structure which circulates the partition member 16 longer than 1 round may be employ | adopted.
Further, as the main body channel 25, for example, a configuration extending in the axial direction or a configuration without the end chamber 34 may be employed.

Moreover, in the said 2nd Embodiment, although the guide surface 141b was formed in the current transformation protrusion 141, you may employ | adopt the current transformation protrusion 141 which does not have the guide surface 141b.
In this case, since the liquid L from the second communication portion 27 side is less likely to reach the counter pore 126a than the non-opposed pore 126b, the flow resistance of the counter pore 126a is reduced to the flow resistance of the non-opposed pore 126b. Further, the ratio of the opening area of the opposed pores 126a in the plane area of the portion facing the current transformation protrusion 141 in the axial direction on the lower surface of the first barrier 38 may be the remaining current transformation. You may make it larger than the ratio of the opening area of the non-opposing pore 126b which occupies the flat area of the part which is not facing the protrusion 141 in the axial direction.

  In the above embodiment, the compression type vibration isolators 1 and 2 in which a positive pressure is applied to the main liquid chamber 14 when a support load is applied have been described. However, the main liquid chamber 14 is positioned on the lower side in the vertical direction. In addition, the auxiliary liquid chamber 15 is attached so as to be positioned on the upper side in the vertical direction, and can be applied to a suspension type vibration isolator in which a negative pressure is applied to the main liquid chamber 14 when a support load is applied.

  In the above embodiment, the partition member 16 partitions the liquid chamber 19 in the first mounting member 11 into the main liquid chamber 14 having the elastic body 13 as a part of the wall surface and the sub liquid chamber 15. It is not limited to this. For example, instead of providing the diaphragm 20, a pair of elastic bodies 13 may be provided in the axial direction, and instead of providing the auxiliary liquid chamber 15, a pressure receiving liquid chamber having the elastic body 13 at a part of the wall surface may be provided. Good. 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 the two liquid chambers can be appropriately changed to another configuration having the elastic body 13 in a part of the wall surface.

  The vibration isolators 1 and 2 according to the present invention are not limited to an engine mount of a vehicle, and can be applied to other than the engine mount. For example, the present invention can be applied to a generator mount mounted on a construction machine, or can be applied to a machine mount installed in a factory or the like.

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

1, 2 Vibration isolator 11 First mounting member 12 Second mounting member 13 Elastic body 14 Main liquid chamber (first liquid chamber)
15 Secondary liquid chamber (second liquid chamber)
16 Partition member 19 Liquid chamber 24 Restriction passage 25 Main body flow path 25a End surface (one end surface)
26, 126 1st communication part 26a, 26b, 126a, 126b Small hole 27 2nd communication part 38 1st barrier 41, 141 Current transformation protrusion L Liquid O Center axis

Claims (4)

A cylindrical first mounting member coupled to one of the vibration generating unit and the vibration receiving unit, and a second mounting member coupled to the other;
An elastic body that elastically connects both the mounting members;
A partition member that divides the liquid chamber in the first mounting member in which the liquid is sealed into a first liquid chamber and a second liquid chamber, and
A liquid-sealed vibration isolator in which a restriction passage communicating the first liquid chamber and the second liquid chamber is formed in the partition member,
The restriction passage includes a first communication portion that opens to the first liquid chamber, a second communication portion that opens to the second liquid chamber, and a main body channel that communicates the first communication portion and the second communication portion. With
At least one of the first communication portion and the second communication portion includes a plurality of pores penetrating the first barrier facing the first liquid chamber or the second liquid chamber,
The main body flow path is provided with a current transformation protrusion that changes the flow direction by colliding liquid from either one of the first communication part and the second communication part,
The anti-vibration device according to claim 1, wherein the current transformation protrusion is opposed to the first barrier in the opening direction of the pore.   The current transformation protrusion is disposed on one end surface of the inner surface of the main body channel, which is located at one end of the first communication portion and the second communication portion and faces the other side. The anti-vibration device according to claim 1, wherein the anti-vibration device is provided.   The flow resistance of the pore facing the current-transforming protrusion in the opening direction of the pore among the plurality of pores is smaller than the flow resistance of the remaining pores. The vibration isolator described in 1.   On the inner surface of the first barrier facing the main body flow path, the ratio of the opening area of the pores to the flat area of the portion facing the current-transforming protrusion in the opening direction of the pores is the remaining portion. The vibration isolator according to any one of claims 1 to 3, wherein the vibration isolator is larger than a ratio of an opening area of the pores to a flat area.

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