JP2006242356A - Fluid filled vibration isolator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid filled vibration isolator in which an abnormal sound can be more certainly prevented from occurring in inputting a vibration. <P>SOLUTION: A plurality of see-through holes 78 allowing two fluid chambers 44 and 46 to communicate with each other is formed mutually independently in a partitioning member 42. A moving plate 52 capable of blocking the whole through holes 78, and movement restricting parts 74 and 76 placed at both sides of the moving plates 52 and capable of freely moving by a definite distance between two fluid chambers 44 and 46 are independently installed respectively corresponding to the through holes 78 so as not to overlap or oppose mutually. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fluid-filled vibration isolator, and in particular, has a plurality of liquid chambers filled with an incompressible fluid, and has a vibration-proof effect based on the fluid flow action between the plurality of liquid chambers. The present invention relates to an improved structure of a fluid-filled vibration isolator.

  Conventionally, as a kind of anti-vibration coupling body or anti-vibration support body interposed between members constituting the vibration transmission system, a first mounting member and a second mounting member are coupled by a main rubber elastic body. In addition, with the main rubber elastic body as a part of the wall portion, a first fluid chamber in which an incompressible fluid is sealed is formed, and a partition member is interposed between the first fluid chamber and the first fluid chamber. While forming the second fluid chamber in which the incompressible fluid is sealed, the partition member is provided with a through hole that allows the first and second fluid chambers to communicate with each other. A movable plate capable of blocking the through-hole is disposed so as to cover the movable plate, and the movable plate is positioned on both sides of the movable plate so as to be separated from the movable plate. Fluid-filled vibration isolator provided with a movement restricting portion that can freely move within a certain distance from the fluid chamber There are known.

  In the fluid-filled vibration isolator having such a structure, the movable plate is moved by the input of vibration, and the first fluid chamber and the second through the through-hole are moved along with the movement of the movable plate. Based on the fluid flow action of fluid flowing between the fluid chambers, it is possible to easily obtain a vibration isolation effect that is difficult to obtain with a rubber elastic body alone. Application is under consideration.

  By the way, in such a vibration isolator, when the movable plate is moved between the first fluid chamber and the second fluid chamber, the movable plate is brought into contact with the movement restricting portion provided in the partition member. Although the amount of movement of the movable plate is regulated, an excitation force is generated due to the impact force generated by the contact of the movable plate with the movement regulating portion, and as a result, the partition member and There is a problem that abnormal noise occurs due to resonance of other members that come into contact. When a shocking heavy load is input, the movable plate strongly hits the movement restricting portion of the partition member, so that a larger abnormal noise including a hitting sound is generated. It was a particularly big problem.

  Therefore, in order to prevent such abnormal noise from occurring, a fluid-filled vibration isolator in which the partition member has a special structure has been proposed (for example, see Patent Document 1 below).

  That is, in such an anti-vibration device, the partition member has two partition bodies made of a single-bottomed cylindrical body having a low height, and these two partition bodies sandwich the movable plate in the axial direction. By being superimposed on each other and assembled, a movable plate is accommodated therein so as to be movable in the axial direction. Further, in such a partition member, a plurality of through holes are provided in the central portion of each partition body covered with the movable plate so as to be adjacent to each other in the circumferential direction, and each of the through holes penetrates the partition member. Holes are formed, and radially extending arm portions are formed between the adjacent through holes. And the rib which exhibits a protrusion form with respect to some of the several arm parts in one partition is integrally formed so that it may extend with mutually different length along the length direction of an arm part. ing.

  Thus, in the vibration isolator having the partition member having such a structure, since the ribs having different lengths are provided at the bottom of one partition constituting the partition member, the movable plate is When moving by vibration input, the timing of contact with the bottom of one of the partitions is partially made different, so that the impact force generated by the contact of the movable plate with the partition member is Is advantageously made smaller than in the case of simultaneously contacting the partition member. As a result, the vibration force generated due to the impact force is reduced, and the generation of abnormal noise due to the resonance of the partition member and the like can be prevented.

  However, in such a conventional fluid-filled vibration isolator, the ribs for preventing the generation of abnormal noise as described above are provided only on one of the two partitions constituting the partition member. Therefore, there has been a drawback that it is impossible to prevent any abnormal noise generated when the movable plate is brought into contact with the other partition. Further, in such a conventional device, the length of each rib must be designed so that the difference in length between the ribs is an appropriate value in order to obtain a sufficient effect of preventing the generation of abnormal noise. There was also a problem that it was extremely troublesome. Moreover, in the conventional apparatus, for example, when the movable plate is brought into contact with one partition having the ribs, a gap is easily formed between the movable plate and the ribs. There was also a problem that it was difficult to ensure sufficient sealing between the partition and the partition.

Japanese Patent No. 2875723

  Here, the present invention has been made in the background as described above, and the problem to be solved is that it is easier and more reliable to prevent the generation of abnormal noise during vibration input. It is an object of the present invention to provide an improved structure of a fluid-filled type vibration damping device that can be realized as described above.

  And in this invention, in order to solve this subject, while connecting a 1st attachment member and a 2nd attachment member with a main body rubber elastic body, this main body rubber elastic body is a part of wall part. Forming a first fluid chamber in which an incompressible fluid is enclosed, and further a second member in which an incompressible fluid is enclosed on the opposite side of the first fluid chamber with a partition member interposed therebetween. While forming the fluid chamber, the partition member is provided with a through hole that allows the first and second fluid chambers to communicate with each other, and further, the through hole is blocked so as to cover the entire through hole. A movable plate capable of being disposed, and positioned on both sides of the movable plate so as to be separated from the movable plate, the movable plate being disposed between the first fluid chamber and the second fluid chamber. In the fluid-filled vibration isolator provided with a movement restricting portion that can freely move by a fixed distance between the above, A plurality of the through holes are provided independently from each other on the cutting member, and the movable plate and the movement restricting portion are not overlapped or opposed to each other corresponding to the plurality of through holes. The gist of the fluid-filled vibration isolator is provided independently.

  Therefore, in such a fluid filled type vibration damping device according to the present invention, each of the plurality of movable plates is disposed so as to block the separate through holes independent from each other, and each of these movable plates is movable. On both sides of the plate, the movement restricting portions are respectively positioned so as to be separated from the movable plate. For this reason, the size of the movable plate can be advantageously made smaller than that of a conventional apparatus in which one movable plate is disposed so as to cover all of one or a plurality of through holes. Therefore, when each movable plate is moved between the first fluid chamber and the second fluid chamber by the input of the vibration load, the impact force generated by the contact of each movable plate with the movement restricting portion is also generated. As the movable plates are made smaller, they can be effectively kept low.

  Further, the size and thickness of each of the plurality of movable plates are slightly different due to a molding error that inevitably occurs during the molding. Furthermore, the opening areas of the plurality of through holes provided in the partition member are hardly matched completely. For this reason, in the device of the present invention in which each of the plurality of movable plates is arranged so as to cover each through hole independently of each other, each of the movable plates is first subjected to input of a vibration load. When the fluid chamber is moved between the second fluid chamber and the second fluid chamber, the timing of contact with the movement restricting portion is slightly different for each movable plate.

  Therefore, in the fluid filled type prevention device according to the present invention, all of the plurality of movable plates are moved against the movement restricting portions located on both sides of each movable plate by the fluid flow action accompanying the input of vibration. Such contact can be advantageously avoided. As a result, the impact force generated by the contact of the movable plate with the movement restricting portion is advantageously made smaller than when a sufficiently large movable plate contacts the partition member.

  Moreover, in the device of the present invention, in order to reduce the impact force generated by the contact of the movable plate with the movement restricting portion, basically, the plurality of through holes and the plurality of movable members are simply formed with respect to the partition member. Since the plates are merely arranged or arranged without any particular limitation on the size of the individual plates, no troublesome design work is required. Further, by arranging the plurality of movable plates in such a manner, the impact force generated by the contact with the movement restricting portion can be surely reduced regardless of the moving direction of each movable plate.

  Therefore, in the fluid filled type vibration isolator according to the present invention, the vibration force generated due to the impact force generated by the contact of the movable plate with the movement restricting portion at the time of vibration input can be advantageously reduced. As a result, the generation of noise due to the contact of the movable plate with the movement restricting portion in such a partition member can be prevented very advantageously and more effectively. And generation | occurrence | production of the bigger abnormal noise at the time of the input of the shocking heavy load which was especially a problem in the past can be prevented very advantageously.

Aspects of the Invention

  By the way, the present invention can be suitably implemented at least in various aspects as listed below.

(1) The first fluid in which the first attachment member and the second attachment member are connected by the main rubber elastic body, and the main rubber elastic body is used as a part of the wall portion and incompressible fluid is enclosed. Forming a chamber and further forming a second fluid chamber in which an incompressible fluid is sealed on the opposite side of the first fluid chamber with a partition member in between, A through-hole that allows the first and second fluid chambers to communicate with each other is provided, and a movable plate capable of blocking the through-hole is disposed so as to cover the whole through-hole, and both sides of the movable plate are disposed. The movable plate is positioned so as to be separated from the movable plate, and the movable plate can freely move by a fixed distance between the first fluid chamber and the second fluid chamber. In the fluid-filled vibration isolator having a portion, the through holes are formed in the partition member independently of each other. A fluid-filled type anti-corrosion, wherein the movable plate and the movement restricting portion are provided independently of each other so as not to overlap or oppose each other corresponding to the plurality of through holes. Shaker.

(2) In the above aspect (1), an orifice passage that connects the first fluid chamber and the second fluid chamber to the partition member is provided. In a fluid-filled vibration isolator having such an orifice passage, by tuning the orifice passage to a low frequency region such as an engine shake, for example, when such a low frequency large amplitude vibration is input. In addition, an effective anti-vibration effect is exhibited based on the resonance action of the fluid flowing through the orifice passage. Moreover, the impact force generated when each movable plate comes into contact with the movement restricting portion can be reliably reduced by the input of the low frequency large amplitude vibration, and as a result, at the time of input of the low frequency large amplitude vibration. Generation of abnormal noise can be effectively prevented.

(3) In the above aspect (1) or aspect (2), the plurality of through holes have different opening areas, and block the respective through holes based on the difference in the opening areas of the through holes. The movable plate must have a different size. In such a fluid filled type vibration isolator having a plurality of movable plates having different sizes, simultaneous contact of the plurality of movable plates with the movement restricting portion can be avoided more advantageously. The impact force caused by the contact of the movable plate with respect to can be further reliably reduced. And as a result, generation | occurrence | production prevention of the noise accompanying the contact of the movable plate with respect to such a movement control part can be achieved still more effectively.

(4) In any one of the above-described aspects (1) to (3), the separation distances between the plurality of movable plates and the corresponding movement restriction portions are configured to be different from each other. Being. Also by this, the timing which contacts a movement control part may be made different for every movable plate. Therefore, even in the fluid-filled vibration isolator configured as described above, it is possible to effectively prevent the generation of noise due to the contact of the movable plate with the movement restricting portion.

(5) In any one of the above aspects (1) to (4), the movable plate is made of an elastically deformable material. In the fluid-filled vibration isolator having such a movable plate, the first through the through hole between the first fluid chamber and the second fluid chamber when inputting vibration other than the low frequency large amplitude vibration. In addition to the anti-vibration effect exhibited based on the fluid flow action of the fluid flowing between the first fluid chamber and the second fluid chamber, the anti-vibration effect based on the elastic deformation action of the movable plate is also advantageously obtained. Will be.

  Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.

  First, in FIG. 1 and FIG. 2, an automobile engine mount as an embodiment of the present invention is schematically shown in a longitudinal sectional form and a top form, respectively. As is clear from these drawings, the engine mount of this embodiment includes a first mounting member 10 as a first mounting member and a second mounting member 12 as a second mounting member. The first mounting bracket 10 and the second mounting bracket 12 are configured to be spaced apart from each other in the vertical direction and to be elastically connected by the main rubber elastic body 14.

  The first mounting bracket 10 is attached to the power unit of the automobile, while the second mounting bracket 12 is attached to the body of the automobile, so that the power unit is supported by the body against vibration. Moreover, under such a mounted state, the power unit weight is exerted, whereby the main rubber elastic body 14 is elastically deformed so that the first mounting bracket 10 and the second mounting bracket 12 are positioned close to each other. Under such a mounting state, main vibrations to be vibrated are input in the approach / separation direction of the first mounting bracket 10 and the second mounting bracket 12 (substantially vertical direction in FIG. 1 which is the mount center axis). The Rukoto. In the following description, the vertical direction means the vertical direction in FIG. 1 in principle.

  More specifically, the first mounting bracket 10 has a substantially disk shape, and a mounting bolt 16 projecting upward is fixed to the center of the first mounting bracket 10. One mounting bracket 10 is fixedly attached to a power unit (not shown). Further, at the center of the lower surface of the first mounting bracket 10, a cup-shaped bracket 18 having a tapered peripheral wall is superposed at the opening and fixed by welding or the like.

  On the other hand, the second mounting bracket 12 has a large-diameter, generally cylindrical shape as a whole. Further, in the second mounting bracket 12, an inner flange portion 20 that protrudes by a predetermined dimension radially inward and continuously extends in the circumferential direction is integrally formed with respect to the peripheral portion of the upper opening. In addition, a portion other than the inner flange portion 20 is a cylindrical portion 22.

  Then, on the substantially central axis of the second mounting bracket 12, the first mounting bracket 10 is disposed so as to be spaced apart above the second mounting bracket 12 and spread in the direction perpendicular to the axis. A main rubber elastic body 14 is interposed between the first mounting bracket 10 and the second mounting bracket 12.

  The main rubber elastic body 14 as a whole has a large-diameter substantially frustoconical shape, and has a recess 24 that opens downward on the end surface on the large-diameter side. In the main rubber elastic body 14, the first mounting bracket 10 is overlapped with the end surface on the small diameter side in a state where the cup-shaped bracket 18 is embedded in the end portion on the small diameter side, and vulcanized. On the other hand, the inner flange portion 20 of the second mounting bracket 12 is overlapped and vulcanized and bonded to the large-diameter side end surface surrounding the recess 24. In short, the main rubber elastic body 14 is formed as an integrally vulcanized molded product including the first mounting bracket 10 and the second mounting bracket 12. Thus, the upper opening of the second mounting member 12 is fluid-tightly covered with the main rubber elastic body 14. An inner seal rubber layer 26 that covers substantially the entire surface of the second mounting bracket 12 is formed integrally with the main rubber elastic body 14. Further, an outer seal rubber layer 28 that covers the lower portion of the cylindrical portion 22 of the second mounting member 12 is integrally formed.

  On the other hand, a mounting ring 30 is disposed in the lower opening of the second mounting bracket 12. The mounting ring 30 is formed with respect to an annular plate portion 32 having an outer diameter larger than the outer diameter of the second mounting bracket 12 and an inner diameter smaller than the inner diameter, and an outer peripheral edge portion of the annular plate portion 32. The upper cylindrical portion 34 that is integrally formed so as to protrude upward with a predetermined height and the inner peripheral edge of the annular plate portion 32 protrude downward with a predetermined height. The lower cylindrical portion 36 is formed integrally with the lower cylindrical portion 36.

  Further, in the mounting ring 30, a diaphragm 38 made of a rubber thin film as a flexible film is disposed inside the lower cylindrical portion 36 so as to cover the entire inner hole of the annular plate portion 32. ing. The diaphragm 38 has a thin disk shape that is slack so as to be easily deformed, and is vulcanized and bonded to the inner peripheral surface of the lower cylindrical portion 36 of the mounting ring 30 at the outer peripheral edge portion. Yes. That is, in other words, the diaphragm 38 is configured as an integrally vulcanized molded product in which the mounting ring 30 is vulcanized and bonded to the outer peripheral edge portion thereof.

  Such a mounting ring 30 is brought into contact with the lower end surface of the second mounting bracket 12 at the outer peripheral portion of the upper surface of the annular plate portion 32, and the second mounting bracket at the upper cylindrical portion 34. For example, the upper cylindrical portion 34 is subjected to a diameter reduction process or the like to be fitted and fixed to the second mounting bracket 12. ing. In such a fixed state, the outer cylindrical surface of the second mounting bracket 12 and the upper cylindrical portion of the mounting ring 30 are formed by the outer seal rubber layer 28 integrally formed on the outer peripheral surface of the second mounting bracket 12. A space between the inner peripheral surface of 34 is liquid-tightly sealed.

  As a result, the lower opening of the second mounting bracket 12 is liquid-tightly covered with the mounting ring 30 and the diaphragm 38 that closes the inner hole thereof. A fluid chamber 40 in which an incompressible fluid is sealed is formed between the opposing surfaces of the main rubber elastic body 14 and the diaphragm 38 that cover (both sides in the axial direction). As the sealing fluid, water, alkylene glycol, polyalkylene glycol, silicone oil, or the like is employed. In order to advantageously obtain a vibration isolation effect based on the resonance action of the fluid described later, in this embodiment, 0 is used. A low-viscosity fluid of 1 Pa · s or less is preferably employed.

  In addition, a partition member 42 is accommodated in the second mounting bracket 12 and assembled in the fluid chamber 40. The partition member 42 has a substantially thick disk shape as a whole, and is fixed to the second mounting member 12 in a state where the partition member 42 spreads in the direction perpendicular to the axis in the fluid chamber 40. Thus, the fluid chamber 40 is partitioned on both upper and lower sides with the partition member 42 interposed therebetween. An upper side of the partition member 42 is a space inside the recess 24 of the main rubber elastic body 14, and a part of the wall portion is configured by the main rubber elastic body 14 as a first fluid chamber. While the pressure receiving chamber 44 is formed, an equilibrium chamber 46 as a second fluid chamber is formed below the partition member 42, and a part of the wall portion is constituted by a diaphragm 38. That is, in the pressure receiving chamber 44, vibration is input along with elastic deformation of the main rubber elastic body 14 at the time of vibration input, and an internal pressure fluctuation is generated, while the equilibrium chamber 46 is based on the deformation of the diaphragm 38. Thus, the volume change is easily allowed and the internal pressure change is absorbed.

  Thus, in the engine mount of the present embodiment, the specific configuration of the partition member 42 that partitions the fluid chamber 40 as described above into two to define the pressure receiving chamber 44 and the equilibrium chamber 46 is conventionally known. There is a big feature not seen in the mount.

  That is, here, the partition member 42 is formed by the partition member main body 48 and the lid body 50 being overlapped with each other and assembled, and, for example, three movable plates 52 are provided therein. Each is arranged so as to be movable in the vertical direction.

  As shown in FIGS. 3 and 4, the partition member main body 48 is formed of a substantially circular block body having a predetermined thickness formed using a hard synthetic resin material or a metal material such as an aluminum alloy. . A circumferential groove 54 having a rectangular cross section extending continuously with a circumferential length of about one round is formed on the outer peripheral portion of the upper surface of the partition member body 48 with a predetermined depth. Further, in the circumferential groove 54, a window portion 56 having a substantially rectangular shape is formed at one end portion of the bottom portion extending in the circumferential direction so as to penetrate the bottom portion.

  On the other hand, of the inner peripheral portion of the upper surface of the partition member main body 48, for example, three circular recesses 58 having a predetermined depth are formed in a portion surrounded by the peripheral groove 54. The three circular recesses 58 are arranged around the center of the partition member body 48 so that the centers of the circular recesses 58 are located at a certain distance in the circumferential direction on the same circumference. Yes.

  In each of these circular recesses 58, the inner surface of the bottom is a smooth surface, and, for example, four through holes 60 having a substantially fan shape are formed in such a bottom in the circumferential direction. Are formed at a certain distance. Further, a portion located between the four through holes 60 at the bottom of the circular recess 58 is a narrow cross-shaped rib 62 extending in a cross shape with a smooth inner surface.

  On the other hand, as is apparent from FIGS. 1, 5, and 6, the lid 50 has the same diameter as the partition member body 48 formed using a hard synthetic resin material or a metal material such as an aluminum alloy. It consists of a circular thin-walled flat plate whose both sides in the thickness direction are smooth surfaces. A window portion 68 having the same shape and size as the window portion 56 provided at the bottom of the circumferential groove 54 of the partition member main body 48 is provided in the outer peripheral portion of the lid member 50 so as to penetrate in the plate thickness direction. It has been.

  In addition, four through holes 64 and cross-shaped ribs 66 are provided at three locations on the inner peripheral portion of the lid 50, and four through holes provided at the bottom of each circular recess 58 of the partition member main body 48. 60 and the cross-shaped rib 62 are arranged at the same position and in the same size and shape, and in the same form as the arrangement form on the bottom of the circular recess 58. In other words, four substantially fan-shaped through holes 64 are provided at three positions of the lid 50 so as to be located in groups of four, and are positioned between adjacent ones of the through holes 64. In addition, a cross-shaped rib 66 is provided.

  7 and 8, the lid 50 having the above-described structure covers the circumferential groove 54 of the partition member body 48 and the three circular recesses 58, and the lid 50 The four through-holes 60 provided in each of the three locations are respectively positioned in the vertical direction with respect to the four through-holes 64 provided in the three circular recesses 58 of the partition member body 48, respectively. In FIG. 4, the upper surface of the partition member main body 48 is overlaid and assembled. Thus, the partition member 42 is configured as an assembly of the partition member main body 48 and the lid body 50.

  Further, in the partition member 42 composed of such an assembly, the circumferential groove 54 of the partition member main body 48 is covered with the lid body 50, so that the orifice extends to the outer peripheral portion with a circumferential length of approximately one round. A passage 70 is formed. The orifice passage 70 is communicated to the outside in the vertical direction through windows 68 and 56 provided on the outer peripheral portions of the lid 50 and the partition member main body 48.

  Further, the three circular recesses 58 of the partition member main body 48 are covered with the lid body 50, so that three accommodating portions 72 are formed on the inner peripheral portion of the partition member 42. That is, each of the three accommodating portions 72 is a lower bottom wall portion 74 provided with four through holes 60 each formed from the bottom portion of each of the three circular recesses 58 in the partition member main body 48. And four through-holes 64 made of the three portions of the inner peripheral portion of the lid 50 that are respectively opposed to the bottom portions of the three circular recesses 58. Each of the upper bottom wall portions 76 is provided so as to be surrounded by a smooth lower surface and a side surface of the circular recess 58.

  In each of the accommodating portions 72, the through holes 60 and 64 of the partition member main body 48 and the lid body 50 are positioned coaxially, and the inner peripheral portion of the partition member 48 is formed by the through holes 60 and 64. A through-hole 78 penetrating therethrough is formed. That is, here, three through holes 78 are provided in each of the three accommodating portions 72. Further, the internal space of each accommodating portion 72 is communicated to the outside through the through hole 78. In other words, the upper opening and the lower opening of each through-hole 78 are formed by four through holes 64 and 60 provided in each of the upper bottom wall 76 and the lower bottom wall 74 of each accommodating portion 72. And the respective accommodating portions 72 are communicated upward and downward through the upper and lower openings formed by the through holes 64 and 60, respectively.

  In addition, in the three accommodating portions 72 having such a configuration, one movable plate 52 is accommodated and held one by one. The movable plate 52 is a rubber circular flat plate having a diameter slightly smaller than the inner diameter of the circular recess 58 of the partition member body 48 and a thickness sufficiently smaller than the depth dimension of the circular recess 58. ing. Such a movable plate 52 is arranged so as to cover substantially the entire lower bottom wall portion 74 of each housing portion 72 in each housing portion 72.

  In this embodiment, for example, the fluid-filled vibration isolator disclosed in Japanese Patent No. 2875723, that is, the movable plate covers all of the plurality of through holes provided in the inner peripheral portion of the partition member. In addition, unlike the structure having a size corresponding to the entire area of the inner peripheral portion and being held by only one partition member, the movable plate 52 is provided at three locations on the inner peripheral portion of the partition member 42. Each one is accommodated in each of the three accommodating portions 72 and is held by the partition member 42. For this reason, the diameter and thickness of each of the three movable plates 52 are sufficiently smaller than the diameter and thickness of the movable plate in the conventional apparatus. Moreover, in such three movable plates 52, although the difference is not positively set in the diameter and thickness of each of them, the sizes are slightly different from each other due to molding errors and the like. Yes.

  In short, in the present embodiment, the accommodating portions 72 are respectively formed at three locations on the inner peripheral portion of the partition member 42, each having an upper bottom wall portion 76 and a lower bottom wall portion 74. In addition, a total of twelve through-holes 78 are formed independently of each other, four for each of the three accommodating portions 72 and a total of the partition member 42. Further, three movable plates 52 smaller than the conventional one are accommodated in each of the three accommodating portions 72 provided with four through holes 78 each. In other words, four through holes 78 are provided at three locations on the inner peripheral portion of the partition member 42, and three locations at which four such through holes 78 are provided. In addition, the movable plates 52 are arranged on the same plane so that the movable plates 52 are not overlapped or opposed to each other.

  Then, the movable plate 52 arranged in each of the three accommodating portions 72 in such an arrangement state covers all the four through holes 78 for each accommodating portion 72, and these four through holes are provided. It is positioned so that all of 78 can be blocked. In addition, the outer diameter of each movable plate 52 is slightly smaller than the inner diameter of each accommodating portion 72 and the thickness thereof is sufficiently smaller than the depth dimension of each accommodating portion 72, so that each movable plate 52 is provided. However, the inside of each accommodating part 72 can be freely moved up and down. The movement of the movable plate 52 in the vertical direction is restricted by the contact between the upper bottom wall portion 76 and the lower bottom wall portion 74 of each housing portion 72.

  As is clear from this, here, the upper bottom wall portion 76 and the lower bottom wall portion 74 provided in each of the three accommodating portions 72 are provided on both sides of each movable plate 52, and each movable plate 52 and Are positioned so as to be separated from each other, and are configured as a pair of movement restricting portions that restrict the movement of each movable plate 52 and make a pair with each other. In addition, the movement restricting portions that make these pairs are arranged on the same plane here so that they do not overlap or oppose each other at three places where four through-holes 78 are gathered. Yes.

  As shown in FIG. 1, the partition member 42 having such a structure extends in the direction perpendicular to the axis on the same axis in the second mounting member 12 (fluid chamber 40), and is a lid. 50 is positioned on the upper side, while the partition member main body 48 is positioned on the lower side, the fluid tightness between the upper surface of the annular plate portion 32 of the ring 30 and the lower end surface of the main rubber elastic body 14 is reduced. It is held and clamped by the screw.

  In addition, under such a state in which the partition member 42 is fixed in the fluid chamber 40, the upper bottom wall portion 76 of each accommodating portion 72 in the partition member 42 is exposed in the pressure receiving chamber 44, while each partition member 72 is exposed. The lower bottom wall portion 74 is exposed in the equilibrium chamber 46, and four through holes 64, 62 provided in the upper and lower bottom wall portions 76, 74 of the respective accommodating portions 72 are received by pressure. The chamber 44 and the equilibrium chamber 46 are opened.

  Accordingly, four through holes 78 provided in each of the accommodating portions 72 are positioned so as to communicate with the pressure receiving chamber 44 and the equilibrium chamber 46, and are balanced with the pressure receiving chambers 44 through the respective through holes 78. Fluid flow between the chambers 46 is allowed. Further, the upper surface and the lower surface of the movable plate 52 accommodated in each accommodating portion 72 are exposed to the pressure receiving chamber 44 and the equilibrium chamber 46 through the respective through holes 78, and the pressure receiving pressure is applied to these upper and lower surfaces. The internal pressure of the chamber 44 and the equilibrium chamber 46 can be exerted.

  Further, under the fixed state of the partition member 42 in the fluid chamber 40, the windows 68 and 56 that open the orifice passage 70 provided in the partition member 42 on both the upper and lower sides are provided in the pressure receiving chamber 44 and the equilibrium chamber 46. The orifice passage 70 is positioned so that the pressure receiving chamber 44 and the equilibrium chamber 46 communicate with each other. Therefore, the pressure receiving chamber 44 and the equilibrium chamber 46 are also connected through the orifice passage 70. Fluid flow between the two is allowed.

  Thus, in the engine mount according to the present embodiment having such a structure, the approach / removal between the first mounting bracket 10 and the second mounting bracket 12 under the mounting state on the automobile. When vibration in the separation direction (vertical direction in FIG. 1) is input, a relative pressure difference is generated between the pressure receiving chamber 44 and the equilibrium chamber 46, so that the space between the chambers 44 and 46 is increased. , The fluid flow through the orifice passage 70, the fluid flow through the plurality of through holes 78 between the pressure receiving chamber 44 and the equilibrium chamber 46, and the elastic deformation of the movable plate 52 are generated. It has become.

  In this case, the orifice passage 70 is tuned to a low frequency region such as an engine shake so that when low frequency large amplitude vibration such as an engine shake is input, the fluid is caused to flow through the orifice passage 70. An effective anti-vibration effect is exhibited based on the resonance action.

  At this time, the movable plates 52 respectively held in the three accommodating portions 72 of the partition member 42 are moved to the pressure receiving chamber 44 side or the equilibrium chamber 46 based on the internal pressure difference between the pressure receiving chamber 44 and the equilibrium chamber 46. It moves to the side (vertical direction), and comes to contact the lower bottom wall part 74 and the upper bottom wall part 76 of each accommodating part 72 in the lower surface and the upper surface. As a result, all of the four through holes 60 and 64 provided in each of the lower and upper bottom wall portions 74 and 76 are closed, and the pressure receiving chambers through the four through holes 78 in each accommodating portion 72 are closed. Thus, the substantial fluid flow between 44 and the equilibrium chamber 46 is prevented, so that the vibration isolation effect based on the fluid flow action through the orifice passage 70 can be more effectively exhibited.

  At this time, the contact surface of each of the accommodating portions 72 with which the movable plate 52 is brought into contact with the upper bottom wall portion 76 and the lower bottom wall portion 74 of the movable plate 52 is a smooth surface, and any protrusions are provided. Not. Moreover, the movable plate 52 is made of a rubber material that can be elastically deformed. Therefore, for example, unlike the above-described conventional device in which ribs having a ridge shape are provided at a contact portion of the partition member 42 with the movable plate 52, the movable plate 52 and the upper side of each accommodating portion 72 to which the movable plate 52 is brought into contact In addition, it is possible to effectively prevent a gap from being formed between the lower bottom wall portions 76 and 74 and impairing the sealing performance. Further, here, protrusions 80 extending continuously in the circumferential direction are provided on both surfaces of the outer peripheral edge portion of the movable plate 52, respectively, and are movable with respect to the upper and lower bottom wall portions 76, 74 of each accommodating portion 72. When the plate 52 is in contact, the protrusion 80 is configured to exhibit a sufficient sealing function.

  Furthermore, in the present embodiment, the movable plate 52 is elastically deformed based on the internal pressure difference between the pressure receiving chamber 44 and the equilibrium chamber 46 when low frequency large amplitude vibration is input. The amount of elastic deformation of the movable plate 52 is limited by the contact of the movable plate 52 with the cross-shaped ribs 66 and 62 provided on the lower bottom wall portions 76 and 74, respectively. Therefore, it is advantageously prevented that the fluid flow amount through the orifice passage 70 becomes insufficient due to the elastic deformation of the movable plate 52 when the low frequency large amplitude vibration is input. The anti-vibration effect can be more effectively exhibited.

  In this embodiment, in particular, as described above, the diameter and size of each of the three movable plates 52 housed one by one in the three housing portions 72 are, for example, the partition in the conventional apparatus. The member has a size corresponding to the entire area of the inner peripheral portion of the partition member, and is sufficiently smaller than the movable plate held by only one member.

  For this reason, at the time of inputting low-frequency large-amplitude vibration, the three movable plates 52 are moved up and down in the respective accommodating portions 72 in the partition member 42, and the upper bottom wall portion 76 of each of the accommodating portions 72 and Each of the movable plates has an impact force generated when it is brought into contact with the lower bottom wall portion 74 as compared with an impact force produced when one large movable plate in the conventional apparatus is brought into contact with the partition member. As the size of 52 is reduced, it can be effectively kept low.

  In addition, as described above, the three movable plates 52 are unexpectedly different in diameter and thickness from each other. Therefore, when such three movable plates 52 are moved up and down in the three accommodating portions 72 in accordance with the input of the low-frequency large-amplitude vibration, the moving speeds and movements of the respective movable plates 52 are moved. The amounts are not uniform with each other, whereby the timing of contact with the upper bottom wall portion 76 and the lower bottom wall portion 74 of each accommodating portion 72 is slightly different for each movable plate 52. That is, all of the three movable plates 52 are simultaneously applied to the upper bottom wall portion 76 and the lower bottom wall portion 74 of each accommodating portion 72 by the fluid flow action accompanying the input of the low frequency large amplitude vibration. Such contact can be advantageously avoided. As a result, the impact force generated by the contact of each movable plate 52 with respect to the upper bottom wall portion 76 and the lower bottom wall portion 74 of each of the accommodating portions 72 is divided by one large movable plate in the conventional apparatus as described above. It is advantageously made smaller than when contacting the member.

  In addition, in the present embodiment, the effect of reducing the impact force caused by the contact of each movable plate 52 with the upper bottom wall 76 and the lower bottom wall 74 of each accommodating portion 72 is simply three movable. In a structure that does not require a very simple and troublesome design work, each of which is arranged so that the plate 52 can cover four of the twelve through-holes 78 provided in the partition member 42. Regardless of the moving direction of the movable plate 52, it can be advantageously achieved.

  On the other hand, four through holes 78 provided in each of the accommodating portions 72 of the partition member 42 are tuned to a frequency range higher than the tuning frequency of the orifice passage 70, thereby high frequency small amplitude such as traveling booming noise. When vibration is input, the orifice passage 70 is substantially closed as the flow resistance of the orifice passage 70 is significantly increased, while the movable plate 52 in each accommodating portion 72 is small in the vertical direction. It can be moved by the amount of movement. At this time, the fluid is caused to flow around the movable plate 52 through the respective through holes 78, so that an effective anti-vibration effect is exhibited. Further, since the movement of the movable plate 52 in each accommodating portion 72 in the vertical direction is sufficiently small, there is no contact of the movable plate 52 with the cross-shaped ribs 66, 62 provided in each accommodating portion 72, and therefore. No abnormal noise is a problem.

  Thus, in the present embodiment, it occurs when the three movable plates 52 come into contact with the upper bottom wall portion 76 and the lower bottom wall portion 74 of each housing portion 72 when low frequency large amplitude vibration is input. The impact force is easily and reliably reduced, and is thereby generated due to the contact of the movable plate 52 with the upper bottom wall portion 76 and the lower bottom wall portion 74 of each accommodating portion 72. The excitation force can also be advantageously reduced.

  Therefore, in the engine mount according to the present embodiment as described above, each of the partition member 42 with respect to the upper bottom wall portion 76 and the lower bottom wall portion 74 of the accommodating portion 72 at the time of input of the low frequency large amplitude vibration. It is possible to reliably prevent the partition member 42 and the like from resonating due to the contact of the movable plate 52 and generating abnormal noise in a simple structure that is easy to design.

  In this embodiment, for example, even when shocking large-amplitude vibration is input, each movable plate 52 is connected to the upper bottom wall 76 or the lower bottom wall of each housing portion 72 in the partition member 42. Contact with the portion 74 with a large impact force can be prevented as much as possible, and thereby the generation of shocking sounds and vibrations can be effectively eliminated.

  As mentioned above, although one Embodiment of this invention was explained in full detail, this is an illustration to the last, Comprising: This invention is not limited at all by the specific description regarding this Embodiment.

  For example, in the above-described embodiment, the first fluid chamber is configured by the pressure receiving chamber 44 in which a part of the wall portion is configured by the main rubber elastic body 14 and the internal pressure fluctuation is caused when the vibration is input. The two fluid chambers are configured by the equilibrium chamber 46 in which a part of the wall portion is configured by the diaphragm 38 and the volume change is easily allowed. However, the first fluid chamber, the second fluid chamber, May be formed in a configuration that is simply partitioned by a partition member and communicated through a through hole. In that sense, there is no problem even if the orifice passage 70 provided in the partition member 42 is omitted.

  Further, the specific structure of the partition member 42 is not limited to the illustrated one, and the first fluid chamber and the second fluid chamber can be defined inside the vibration isolator, If a plurality of movable plates that have a plurality of through holes and are positioned so as to correspond to each of the plurality of through holes have a structure arranged so as to block the through holes, for example, You may comprise only one component (member), and may comprise combining 3 or more components (member).

  Further, the number, shape, and arrangement position of the plurality of through holes 78 provided in the partition member 42 are not limited to those shown in the embodiment.

  Furthermore, in the above embodiment, the opening areas of the plurality of through holes 78 are all the same size, and the plurality of movable plates 52 are all the same size accordingly. For example, FIG. As shown in FIG. 10, a plurality (here, three) of accommodating portions 72 having different sizes are formed with respect to the partition member 42, and the upper bottom wall of each such accommodating portion 72 is formed. A plurality of through holes 78 are formed in the partition member 42 by providing through holes 64 and 60 having different opening areas for each accommodating portion 72 in the portion 76 and the lower bottom wall portion 74. You may form so that it may have an opening area of a different magnitude | size. And based on the difference of the opening area of the several through-hole 78 so that the through-hole 78 provided in each such accommodating part 72 can be interrupted | blocked, several different sizes were set for each accommodating part 72 One movable plate 52 can be accommodated and held in each accommodating portion 72. 9 and 10 and FIGS. 11 and 12 to be described later, the same reference numerals as those in FIGS. The explanation was omitted.

  According to such a structure, the flow rates of the fluids allowed to flow through the respective through holes 78 are made different from each other based on the difference in the opening area of each through hole 78, and the respective through holes 78 are blocked. Since each movable plate 52 has a different size, simultaneous contact of the plurality of movable plates 52 with respect to the upper bottom wall portion 76 and the lower bottom wall portion 74 of each housing portion 72 can be avoided more advantageously. Thereby, the impact force generated by the contact of the plurality of movable plates 52 with respect to the upper bottom wall portion 76 and the lower bottom wall portion 74 of each housing portion 72 can be more reliably reduced. As a result, it is possible to further effectively prevent the generation of noise due to the contact of the plurality of movable plates 52 with respect to the upper bottom wall portion 76 and the lower bottom wall portion 74 of each accommodating portion 72. .

  In the embodiment, the distance between the upper bottom wall portion 76 and the lower bottom wall portion 74 as the movement restricting portion provided in each accommodating portion 72 in the partition member 42 is constant, and each movable portion is movable. The thickness of the plate 52 is also constant, and the distances between the movable plates 52 and the corresponding upper and lower bottom wall portions 76 and 74 are all the same, so that the movement of the movable plates 52 is performed. The distance was all the same. However, for example, as shown in FIG. 11 and FIG. 12, the thickness of the upper bottom wall 76 and the lower bottom wall 74 is changed for each housing portion 72, so The distances between the movable plates 52 and the corresponding upper and lower bottom wall portions 76 and 74 are made different from each other by making the distances of the movable plates 52 different from each other or by making the plurality of movable plates 52 have different thicknesses. Therefore, the moving distances of the movable plates 52 can be different from each other.

  Even with such a structure, simultaneous contact of the plurality of movable plates 52 with respect to the upper bottom wall portion 76 and the lower bottom wall portion 74 of each housing portion 72 can be avoided more advantageously, and each such housing portion 72 can be avoided. The impact force generated by the contact of the plurality of movable plates 52 with respect to the upper bottom wall portion 76 and the lower bottom wall portion 74 can be more reliably reduced. As a result, it is possible to further effectively prevent the generation of noise due to the contact of the plurality of movable plates 52 with respect to the upper bottom wall portion 76 and the lower bottom wall portion 74 of each accommodating portion 72. .

  Further, the movable plate 52 is not limited in shape, size, and number of arrangements to the illustrated ones. For example, depending on the shape, size, number of arrangements of the through holes 78 and the accommodating portions 72, etc. Needless to say, it is determined appropriately.

  In addition, as a material for forming the movable plate 52, an elastic material other than rubber or a material other than the elastic material can be used as appropriate.

  Further, the structure of the movement restricting portion is not limited to the illustrated one. For example, the upper concave wall portion 76 or the lower bottom wall portion 74 of the accommodating portion 72 or the circular concave portion that provides the side surface of the accommodating portion 72 is used. The movement restricting portion can also be configured by providing a protrusion or the like on the side surface of the place 58.

  In addition, a specific example of applying the present invention to an engine mount of an automobile has been shown.However, the present invention is also applied to a fluid-filled vibration isolator used in various apparatuses other than an automobile body mount and an automobile. Of course, either can be applied advantageously.

  In addition, although not enumerated one by one, the present invention can be carried out in an embodiment to which various changes, modifications, improvements, etc. are added based on the knowledge of those skilled in the art. It goes without saying that all are included in the scope of the present invention without departing from the spirit of the present invention.

It is longitudinal cross-sectional explanatory drawing which shows one Embodiment of the fluid enclosure type vibration isolator which has a structure according to this invention, Comprising: It is a figure equivalent to the II cross section in FIG. FIG. 2 is an explanatory top view of the fluid filled type vibration damping device shown in FIG. 1. FIG. 5 is a longitudinal cross-sectional explanatory view showing an example of a partition member main body constituting a partition member mounted on the fluid filled type vibration isolator shown in FIG. 1, corresponding to a section taken along line III-III in FIG. 4. FIG. 4 is an upper surface explanatory view of the partition member main body shown in FIG. 3. FIG. 7 is a longitudinal cross-sectional explanatory view showing an example of a lid that constitutes a partition member mounted on the fluid-filled vibration isolator shown in FIG. 1, corresponding to a VV cross section in FIG. 6. FIG. 6 is an upper surface explanatory view of the lid shown in FIG. 5. It is a longitudinal cross-sectional explanatory drawing which shows an example of the partition member with which the fluid enclosure type vibration isolator shown by FIG. 1 is mounted | worn, Comprising: It is a figure corresponded in the VII-VII cross section in FIG. FIG. 8 is an upper surface explanatory view of the partition member shown in FIG. 7. It is a figure corresponding to FIG. 7 which shows another example of the partition member with which the fluid filled type vibration isolator shown by FIG. 1 is mounted | worn. It is upper surface explanatory drawing of the partition member shown by FIG. It is a figure corresponding to FIG. 7 which shows another example of the partition member with which the fluid enclosure type vibration isolator shown by FIG. 1 is mounted | worn. It is a figure corresponding to FIG. 7 which shows the other example of the partition member with which the fluid enclosure type vibration isolator shown by FIG. 1 is mounted | worn.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 1st mounting bracket 12 2nd mounting bracket 14 Main body rubber elastic body 38 Diaphragm 40 Fluid chamber 42 Partition member 44 Pressure receiving chamber 46 Equilibrium chamber 48 Partition member main body 50 Lid body 52 Movable plate 60, 64 Through hole 70 Orifice passage 72 Housing part 74 Lower bottom wall part 76 Upper bottom wall part 78 Through hole

Claims (5)

The first attachment member and the second attachment member are connected by a main rubber elastic body, and the main rubber elastic body is used as a part of a wall portion to form a first fluid chamber in which an incompressible fluid is enclosed. In addition, a second fluid chamber in which an incompressible fluid is sealed is formed on the opposite side of the first fluid chamber with a partition member in between. And a second through-hole that allows the second fluid chamber to communicate with each other, and a movable plate that can block the through-hole is disposed so as to cover the whole through-hole, and on both sides of the movable plate, There is provided a movement restricting portion that is positioned so as to be separated from the movable plate and that can freely move the movable plate by a certain distance between the first fluid chamber and the second fluid chamber. In the fluid-filled vibration isolator,
A plurality of the through holes are provided independently from each other with respect to the partition member, and the movable plate and the movement restricting portion do not overlap or oppose each other corresponding to the plurality of through holes. And a fluid-filled vibration isolator provided independently of each other.   The fluid-filled vibration isolator according to claim 1, wherein an orifice passage that communicates the first fluid chamber and the second fluid chamber is provided with respect to the partition member.   The plurality of through holes have different opening areas, and based on the difference in the opening areas of the through holes, the sizes of the movable plates that block the through holes are different from each other. The fluid-filled vibration isolator according to claim 1 or 2.   The fluid-filled vibration isolation system according to any one of claims 1 to 3, wherein the plurality of movable plates and the movement restricting portions corresponding to the plurality of movable plates are different from each other. apparatus. The fluid-filled vibration isolator according to any one of claims 1 to 4, wherein the movable plate is made of an elastically deformable material.

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