JP2008032030A - Fluid-sealed damping device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid-sealed damping device capable of advantageously developing an excellent damping effect by a structure easily manufacturable and having excellent durability. <P>SOLUTION: A pressure receiving chamber 32 and an equilibrium chamber 34 are formed between a first mounting member 10 and a second mounting member 12 connected to each other through a body rubber elastic body 14 on both sides of a partition member 30. An orifice passage 50 allowing the pressure receiving chamber 32 to communicate with the equilibrium chamber 34 is formed of a tubular part 38 formed of a rubber elastic body which is formed integrally with the partition member 30. A projection 40 projecting in the direction crossing the axial direction is formed integrally with one end of the tubular part 38 positioned in the pressure receiving chamber 32. A narrowed part 52 is formed between the end surface of the projection 40 and the inner wall surface of the pressure receiving chamber 32. <P>COPYRIGHT: (C)2008,JPO&INPIT

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 type 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 that are spaced apart from each other are used. Are connected by a main rubber elastic body interposed therebetween, and a partition member supported by the second mounting member is sandwiched, and a part of the wall portion is formed by the main rubber elastic body on the first mounting member side. It is configured to form a pressure receiving chamber in which a predetermined incompressible fluid is enclosed, in which internal pressure fluctuation is caused when vibration is input, while a part of the wall portion is flexible on the side opposite to the pressure receiving chamber An equilibrium chamber composed of a membrane, in which a volume change is allowed based on the deformation of the flexible membrane, in which a predetermined incompressible fluid is sealed, is formed, and the pressure receiving chamber, the equilibrium chamber, 2. Description of the Related Art A fluid-filled vibration isolator configured by providing orifice passages that communicate with each other is known.

  In the fluid-filled vibration isolator having such a structure, the rubber elastic body alone is based on the flow action of the incompressible fluid circulated in the orifice passage due to the internal pressure fluctuation of the pressure receiving chamber at the time of vibration input. It is possible to easily obtain an excellent anti-vibration effect that is difficult to obtain. Therefore, for example, it is advantageously employed as an automobile engine mount, body mount, differential mount, and the like.

  By the way, in such a fluid-filled vibration isolator, the required vibration isolating characteristics have been advanced with the recent upgrading of automobiles. In particular, it is desired that a sufficient anti-vibration effect can be exhibited for any of a plurality of types of vibration having different frequency ranges.

  Therefore, as one of the things that can meet such a demand, for example, in Patent Document 1 below, an action member that spreads in an umbrella shape in a pressure receiving chamber is supported by a first mounting member. There has been proposed a fluid-filled vibration isolator in which a constricted flow path (constricted portion) is formed between the inner wall surface of the material.

  In the fluid-filled vibration isolator having such a structure, for example, when a low frequency vibration such as a shake is input, an excellent damping effect is exhibited based on the resonance action of the fluid that flows in the orifice passage. In addition, at the time of vibration input in a high frequency range, effective flow action or fluid of the fluid that is caused to flow through the constricted flow path due to displacement (vibration) of the action member accompanying elastic deformation of the main rubber elastic body A resonance action is induced, and based on this, a sufficiently low dynamic spring effect is exhibited. Thus, in such a fluid filled type vibration isolator, an excellent anti-vibration effect for a plurality of types of vibrations having different frequencies from a low frequency range to a high frequency range can be exhibited.

  However, in such a conventional fluid-filled vibration isolator, the partition member overlaps, for example, a lower metal fitting having a recess opened at the upper part and the lower metal fitting so as to cover the recess. The upper metal fitting is composed of two metal fittings, an orifice passage is formed between the lower metal fitting and the upper metal fitting, and the umbrella-shaped working member is provided with the partition member. It was composed of separate and independent members. For this reason, in the conventional fluid-filled vibration isolator capable of obtaining a sufficient anti-vibration effect with respect to a plurality of types of input vibrations as described above, the pressure receiving chamber is simply a prerequisite technology. Compared to a fluid-filled vibration isolator that only has an equilibrium chamber and an orifice passage that communicates them, the number of parts is inevitably increased, thereby complicating the structure and accordingly. However, the problem that productivity was also lowered was inherent.

  In Patent Document 2 below, the partition member has a plate-shaped partition portion that partitions the pressure receiving chamber and the equilibrium chamber, and an opening portion that opens to each of the pressure receiving chamber and the equilibrium chamber. There is disclosed a fluid-filled vibration isolator having an orifice passage formed by an inner hole of the nozzle portion formed integrally with a central nozzle portion. In such an anti-vibration device, the partition member having the orifice passage is constituted by only one member, so that the number of parts can be reduced, but the partition member is a metal press-formed product. When elastic deformation of the main rubber elastic body is caused by vibration input, the main rubber elastic body and the nozzle portion are damaged or deformed due to the contact between the main rubber elastic body and the nozzle portion, thereby significantly impairing the durability. There was a fear of it.

Japanese Patent No. 2510903 JP-A-9-166174

  Here, the present invention has been made in the background as described above, and the problem to be solved is that the excellent vibration-proofing effect against a plurality of types of vibrations having different frequencies is simple and manufactured. It is an object of the present invention to provide a fluid filled type vibration damping device that can be advantageously exhibited with a structure that is easy to perform and that does not impair durability.

  In the present invention, in order to solve such a problem, the gist of the present invention is that a first mounting member and a second mounting member that are spaced apart from each other are interposed between them. The main rubber elastic body connects the partition member supported by the second mounting member, and a part of the wall portion is formed by the main rubber elastic body on the first mounting member side. A pressure receiving chamber in which a predetermined incompressible fluid is sealed is formed, and a wall portion is formed of a flexible membrane on the opposite side of the pressure receiving chamber. Configured to form an equilibrium chamber in which a predetermined incompressible fluid is enclosed, in which volume change is allowed based on deformation of the flexible membrane, and the pressure receiving chamber and the equilibrium chamber are mutually connected. In the fluid-filled vibration isolator constructed by providing an orifice passage communicating with the A cylindrical portion made of a rubber elastic body is provided integrally with the partition member, and the orifice passage is connected to the cylindrical shape. And a projecting portion projecting in a direction intersecting the axial direction is integrally formed at the one end portion of the cylindrical portion, and the leading end surface of the projecting portion and the inner wall surface of the pressure receiving chamber The fluid-filled vibration isolator is characterized by providing a constriction between the two.

  Moreover, according to one of the preferable aspects of the fluid-filled vibration isolator according to the present invention, the partition member is in contact with the incompressible fluid in the pressure receiving chamber on one side, and on the other side, It has a plate-shaped partition part which contacts the incompressible fluid in the said equilibrium chamber, and the said cylindrical part is integrally formed with respect to this plate-shaped partition part.

  Furthermore, according to another preferred aspect of the present invention, the plate-shaped partitioning portion is made of a rubber elastic body and can be elastically deformed by a fluid pressure difference between the pressure receiving chamber and the equilibrium chamber. Configured.

  Furthermore, according to one of the desirable modes of the present invention, the whole partition member is constituted by a rubber elastic body.

  The present invention can be suitably implemented in various aspects as listed above in order to solve the problems described above or the problems grasped from the description of the entire specification and the drawings. Each aspect described above can be employed in any combination. It should be noted that the aspects or technical features of the present invention are not limited to those described above, and can be recognized based on the description of the entire specification and the inventive concept disclosed in the drawings. Should be understood.

  That is, in the fluid-filled vibration isolator according to the present invention, an excellent damping effect against low-frequency vibration can be exhibited based on the resonance action of the fluid that flows in the orifice passage, and the fluid-filled vibration isolator can flow through the constriction. Excellent low dynamic spring effect against high-frequency vibrations is exhibited by the flow action or resonance action of the fluid to be produced, and therefore, excellent anti-vibration effects against multiple types of vibrations ranging from the low frequency range to the high frequency range are effectively exhibited. It can be done.

  In the apparatus of the present invention, since the orifice passage is constituted by a cylindrical portion formed integrally with the partition member, for example, the orifice passage is provided on a member separate from the partition member. Or, unlike the conventional device in which the partition member is constituted by an assembly of two members and an orifice passage is formed between the two members, only one partition member and one orifice passage are provided. It is possible to comprise by this member. In addition, since the narrowed portion is provided between the distal end surface of the protruding portion formed integrally with the inner wall surface of the pressure receiving chamber at the distal end portion of the cylindrical portion integrally formed with the partition member, the conventional device Unlike this, it is possible to eliminate the necessity of providing an action member or the like made of a member separate from the partition member in order to form such a narrowed portion.

  Further, in the fluid filled type vibration damping device according to the present invention, since the cylindrical portion and the protruding portion formed integrally therewith are both made of a rubber elastic body, the elasticity of the main rubber elastic body due to vibration input. At the time of deformation, it is advantageously prevented that the cylindrical portion and the protruding portion, and the main rubber elastic body are damaged by the contact between the cylindrical portion and the protruding portion and the main rubber elastic body. As a result, sufficient durability in the entire vibration isolator can be stably secured.

  Therefore, in the fluid-filled vibration isolator according to the present invention as described above, the excellent anti-vibration effect against a plurality of types of vibrations having different frequencies from the low frequency range to the high frequency range is simple and easy to manufacture. Moreover, it can be advantageously exhibited with a structure that does not impair the durability.

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

  First, FIG. 1 schematically shows an automotive engine mount as an embodiment of a fluid-filled vibration isolator according to the present invention in the form of a longitudinal section thereof. As is clear from FIG. 1, the engine mount of the present embodiment includes a first mounting bracket 10 as a first mounting member and a second mounting bracket 12 as a second mounting member. The first mounting bracket 10 and the second mounting bracket 12 are spaced apart from each other in the vertical direction and are elastically connected by the main rubber elastic body 14. The first mounting bracket 10 is attached to the power unit side, and the second mounting bracket 12 is attached to the vehicle body side, so that the power unit is supported in a vibration-proof manner with respect to the vehicle body. Further, at the time of such mounting, a power unit load is applied to the engine mount, and a main vibration load to be vibration-proofed is input in the vertical direction. 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 cylindrical block shape. Further, a female screw hole 16 into which a mounting bolt is screwed is formed at the center of the upper surface of the first mounting bracket 10.

  On the other hand, the second mounting member 12 as a whole has a substantially stepped cylindrical shape that is open in both the upper and lower directions and whose upper side is larger in diameter than the lower side. The upper portion is the large diameter portion 18, while the lower portion is the small diameter portion 20. The second mounting bracket 12 is attached to the vehicle body by, for example, being press-fitted and fixed to a bracket (not shown) attached to the vehicle body. It has become.

  Moreover, the main rubber elastic body 14 that connects the first mounting bracket 10 and the second mounting bracket 12 has a substantially truncated cone shape as a whole. Then, with respect to the end surface on the small diameter side of the main rubber elastic body 14, the first mounting bracket 10 is vulcanized in a state where most of the portion other than the upper surface is embedded in the small diameter side portion of the main rubber elastic body 14. On the other hand, the entire inner peripheral surface of the large-diameter portion 18 of the second mounting bracket 12 is vulcanized and bonded to the end surface on the large-diameter side. That is, the main rubber elastic body 14 is formed as an integrally vulcanized molded product having the first mounting bracket 10 and the second mounting bracket 12. Thereby, the first mounting bracket 10 and the second mounting bracket 12 are elastically connected by the main rubber elastic body 14, and the upper opening of the second mounting bracket 12 is fluid-tight. It is covered with.

  The main rubber elastic body 14 is integrally formed with a seal rubber layer 22 vulcanized and bonded to the entire inner peripheral surface of the small diameter portion 20 of the second mounting bracket 12. Further, in the seal rubber layer 22, the portion located above the intermediate portion is thicker than the portion located below the intermediate portion in the height direction of the small diameter portion 20. A step portion 24 is provided.

  A cylindrical support sleeve 26 having a low height is disposed inside the lower end portion of the small-diameter portion 20 in the second mounting bracket 12 via a thin portion of the seal rubber layer 22 so as to be fixed in position. . The support sleeve 26 is, for example, press-fitted into the lower end portion of the small diameter portion 20 from the lower opening of the second mounting bracket 12 or disposed inside the lower end portion of the small diameter portion 20. In the state, the small-diameter portion 20 is fixed in the lower end portion of the small-diameter portion 20 by subjecting the small-diameter portion 20 to diameter reduction processing such as eight-way drawing. A diaphragm 28 as a flexible film made of a thin disk-like rubber elastic film is bonded to the inner peripheral surface of the support sleeve 26 by vulcanization on the outer peripheral surface. The lower opening of the second mounting bracket 12 is covered with a fluid tight cover.

  Thus, in the engine mount of the present embodiment, a fluid chamber in which a predetermined incompressible fluid is sealed is formed between the main rubber elastic body 14 and the diaphragm 28 inside the second mounting bracket 12. Yes. As the incompressible fluid enclosed in the fluid chamber, for example, water, alkylene glycol, polyalkylene glycol, silicone oil or the like is preferably used.

  In such a fluid chamber, a partition member 30 is accommodated and supported by the second mounting member 12, and the fluid chamber is divided into two by this partition member 30. Accordingly, a part of the wall portion is configured by the main rubber elastic body 14 on the first mounting member 10 side with the partition member 30 in the fluid chamber interposed therebetween, and a pressure receiving chamber 32 in which an internal pressure fluctuation is caused when vibration is input. On the other hand, on the side opposite to the pressure receiving chamber 32 with the partition member 30 in between, a part of the wall portion is constituted by a diaphragm 28, and the volume change is easily performed based on the deformation of the diaphragm 28. An allowed equilibrium chamber 34 is provided.

  The operation of forming the pressure receiving chamber 32 and the equilibrium chamber 34 in which the incompressible fluid is sealed is performed, for example, in the second mounting bracket 12 connected to the first mounting bracket 10 by the main rubber elastic body 14. The operation of inserting and fixing the partition member 30 and the support sleeve 26 to which the diaphragm 44 is vulcanized and bonded is performed easily in an incompressible fluid to be sealed.

  Thus, in the engine mount of this embodiment, the partition member 30 that defines the pressure receiving chamber 32 and the equilibrium chamber 34 in the fluid chamber has a special structure.

  That is, the partition member 30 includes a plate-shaped partition portion 36, a tubular portion 38, and a protruding portion 40. The plate-like partition part 36 has a disk shape having a diameter smaller than the inner diameter of the small-diameter part 20 in the second mounting bracket 12 as a whole, and its outer peripheral part is a metal annular plate. On the other hand, the inner peripheral portion (center side portion) is a movable plate portion 44 made of a thick circular rubber elastic plate than the support plate portion 42. In addition, a circular through hole 46 that penetrates the movable plate portion 44 in the thickness direction is provided at the center of the movable plate portion 44.

  The tubular portion 38 has a substantially thick cylindrical shape as a whole, and is integrated with the opening peripheral edge portion of the through-hole 46 in the upper surface of the central portion of the plate-like partition portion 36 so as to extend vertically upward at a predetermined height. Is erected. That is, the entire cylindrical portion 38 is made of a rubber elastic body that constitutes the movable plate portion 44, and has an inner hole that extends in the vertical direction with the same inner diameter as the through hole 46. Such an inner hole opens upward through the opening on the upper tip side of the cylindrical portion 38, and on the other hand, the plate-shaped partition portion 36 passes through the through hole 46 provided in the movable plate portion 44. On the lower surface of the (movable plate portion 44), it opens downward.

  The protruding portion 40 protrudes in a direction perpendicular to the axis with respect to the outer peripheral surface of the upper end portion of the cylindrical portion 38 with a height dimension that is smaller than the radius of the plate-like partition portion 36, and is circumferential in the entire circumference Are integrally formed with an outer flange extending continuously. That is, the entire protrusion 40 is made of a rubber elastic body that constitutes the movable plate portion 44 and the tubular portion 38. As a whole, it has a relatively thick annular plate shape having an outer diameter smaller than the outer diameter of the plate-like partition portion 36 by a predetermined dimension. Further, in the protruding portion 40, the upper outer corner portion of the annular plate shape is cut obliquely over the entire circumference so as to be chamfered, so that the upper portion of the outer peripheral portion A tapered surface portion 48 having a diameter increasing toward is formed. The taper angle of the taper surface portion 48 is approximately the same as the taper angle of the taper surface portion of the lower surface of the main rubber elastic body 14.

  In short, in the engine mount of the present embodiment, the partition member 30 has a thick disc-shaped movable plate portion 44 and a thick cylindrical tube-like tube standing on the upper surface of the central portion of the movable plate portion 44. A rubber elastic member integrally including a portion 38 and a thick annular plate-like protruding portion 40 provided around the upper outer peripheral surface of the cylindrical portion 38; and a support plate portion 42 made of an annular metal plate. The support plate portion 42 is vulcanized with the inner peripheral portion embedded in the outer peripheral portion of the movable plate portion 44 with respect to the outer peripheral surface of the movable plate portion 44 in the rubber elastic member. It is configured as a bonded vulcanized molded product.

  The partition member 30 having such a structure is accommodated in the fluid chamber so that the tapered surface portion 48 of the protruding portion 40 is opposed to the tapered lower surface of the main rubber elastic body 14 with a predetermined distance. Has been placed. In such an arrangement state, the outer peripheral edge portion of the support plate portion 42 has an upper end surface of the support sleeve 26 supported by the second mounting bracket 12 and an inner periphery of the small-diameter portion 20 of the second mounting bracket 12. The whole partition member 30 is supported by the second mounting member 12 so as to be liquid-tightly sandwiched between the stepped portion 24 of the sealing rubber layer 22 fixed to the surface.

  Thus, here, the pressure receiving chamber 32 and the equilibrium chamber 34 are provided on the upper side and the lower side of the partition member 30 with the plate-like partition portion 36 interposed therebetween, and are provided on the upper surface of the plate-like partition portion 36. The entire cylindrical portion 38 is disposed in the pressure receiving chamber 32. The cylindrical portion 38 is opened in the pressure receiving chamber 32 at the upper end opening portion, and the equilibrium chamber is passed through the through hole 46 of the plate-like partition portion 36 (movable plate portion 44) at the lower end opening portion. 34 is opened. As a result, the pressure receiving chamber 32 and the equilibrium chamber 34 are communicated with each other through the inner hole of the cylindrical portion 38 and the through hole 46, and thus the inner hole of the cylindrical portion 38 and the penetration of the plate-like partition portion 36. An orifice passage 50 that allows fluid to flow between the pressure receiving chamber 32 and the equilibrium chamber 34 is formed by the hole 46. Here, the flow path length and the cross-sectional area of the orifice passage 50 are tuned to a low frequency range.

  Further, in the present embodiment, as described above, the entire cylindrical portion 38 is disposed in the pressure receiving chamber 32, so that the cylindrical portion 38 is integrally formed with an annular plate shape on the outer peripheral surface of the upper end portion. The entire protrusion 40 is also positioned in the pressure receiving chamber 32. And the main body which comprises the front end surface of the protrusion part 40, and the inner wall face of the pressure receiving chamber 32 because the outer diameter of this protrusion part 40 is made smaller than the outer diameter of the plate-shaped partition part 36 so that it may make the above-mentioned. The rubber elastic body (seal rubber layer 22) is opposed to the inner peripheral surface at a narrow interval in the protruding direction of the protruding portion 40. As a result, the upper part and the lower part of the pressure receiving chamber 32 are communicated between the front end surface of the protrusion 40 and the inner peripheral surface of the main rubber elastic body (seal rubber layer 22). Thus, an annular constriction 52 that allows fluid to flow between these portions is formed.

  Furthermore, in the present embodiment, the pressure receiving chamber 32 and the equilibrium chamber 34 are respectively positioned on the upper side and the lower side of the partition member 30 with the plate-like partition portion 36 interposed therebetween, so that the plate-like partition portion. The 36 movable plate portions 44 are brought into contact with the incompressible fluid in the pressure receiving chamber 32 on the upper surface thereof, and are brought into contact with the incompressible fluid in the equilibrium chamber 34 on the lower surface thereof. Then, when the high frequency vibration is input between the first mounting bracket 10 and the second mounting bracket 12, the movable plate portion 44 is based on the fluid pressure difference between the pressure receiving chamber 32 and the equilibrium chamber 34. A pressing force is applied to the upper surface and the lower surface, so that it is elastically minutely deformed (vibrated) in the thickness direction.

  Thus, in this embodiment, when a low-frequency large-amplitude vibration such as a shake is input, a high damping effect for the low-frequency vibration is exhibited based on the resonance action of the fluid that flows in the orifice passage 50. On the other hand, when high-frequency small-amplitude vibration such as a booming sound is input, based on the fluid flow (vibration) caused by the elastic minute deformation of the movable plate portion 44, the high-frequency vibration is insulated or blocked by a low dynamic spring action. The effect has come to be demonstrated. Further, at the time of vibration input in such a high frequency range that the low dynamic spring effect due to such deformation of the movable plate portion 44 cannot be effectively exhibited, based on the fluid flow action or resonance action through the constriction 52, With respect to vibration in a higher frequency range, an insulating or blocking effect by an excellent low dynamic spring action is exhibited.

  Thus, in the engine mount of this embodiment, the partition member 30 made of a single integral vulcanization molded product is simply arranged in the fluid chamber and supported by the second mounting bracket 12, so that the pressure receiving chamber 32 and the equilibrium chamber 34 are defined, and simultaneously, the orifice passage 50, the constricted portion 52, and the movable plate portion 44 are provided at once and very easily, so that the frequency from the low frequency range to the high frequency range is mutually reduced. An excellent anti-vibration effect against a plurality of types of vibrations having different values can be obtained very effectively.

  Therefore, in the engine mount of this embodiment as described above, for example, the orifice passage 50 is provided in a member separate from the partition member 30, or the partition member 30 is configured by assembling two members together. A conventional device in which the orifice passage 50 is provided between the two members assembled with each other, a conventional device in which the member for forming the narrowed portion 52 is formed of a member separate from the partition member 30, Compared to a conventional device or the like in which the movable plate portion 44 is formed of a member separate from the partition member 30, the number of parts is reduced as much as possible, thereby improving the manufacturability and reducing the cost. In addition, with such an advantageous structure, an excellent anti-vibration effect against a plurality of types of vibrations having different frequencies can be ensured extremely effectively.

  Further, in such an engine mount, with respect to the cylindrical portion 38 provided so as to extend upward or protrude from the upper surface of the plate-like partition portion 36 in the partition member 30, and the upper end portion of the cylindrical portion 38. The protrusion 40 projecting in the direction perpendicular to the axis is made of a rubber elastic body. Therefore, for example, when the inner wall surface of the main rubber elastic body 14 is brought into contact with the cylindrical portion 38 or the protruding portion 40 due to elastic deformation of the main rubber elastic body 14 due to vibration input, the cylindrical portion 38 or The contact portion of the protruding portion 40 with the main rubber elastic body 14 can be easily elastically deformed, so that the main rubber elastic body 14, the cylindrical portion 38, and the protruding portion 40 are damaged by mutual contact. Such can be effectively prevented. As a result, the vibration-proofing effect is excellent for a plurality of types of vibrations over a wide frequency range from the low frequency range to the high frequency range as described above without causing any deterioration in durability. Is obtained.

  Furthermore, in the present embodiment, the upper portion of the outer peripheral portion of the protruding portion 40 in the partition member 30 is also a tapered surface portion 48 corresponding to the tapered portion of the lower surface of the main rubber elastic body 14, so that the protruding portion 40 Damage due to mutual contact with the main rubber elastic body 14 can be effectively prevented.

  Furthermore, in the present embodiment, the plate-like partition portion 36 that contacts the fluid in the pressure receiving chamber 32 and the fluid in the equilibrium chamber 34 on the one side and the other side in the plate thickness direction, respectively. In addition, since the tubular portion 38 is integrally formed, an increase in the height of the entire partition member 30 due to the formation of the tubular portion 38 is suppressed as small as possible, and the partition member 30, and thus the entire engine mount, is reduced. It is possible to advantageously prevent the increase in size.

  Further, in the engine mount of this embodiment, the outer peripheral portion of the plate-like partition portion 36 is the support plate portion 42 made of a metal annular plate, and the outer peripheral edge made of the metal portion of the plate-like partition portion 36. Is sandwiched between the upper end surface of the support sleeve 26 and the stepped portion 24 of the seal rubber layer 20 and supported by the second mounting bracket 12, for example, the outer peripheral edge of the plate-like partition 36 is Compared to the case of a rubber elastic body, the supporting force of the plate-like partition portion 36 by the second mounting bracket 12 can be ensured more stably and reliably.

  The specific configuration of the present invention has been described in detail above. However, this is merely an example, and the present invention is not limited by the above description.

  For example, the overall shape and size of the protruding portion 40 can be changed and determined as appropriate according to the size of the constricted portion 52 required to obtain a target vibration-proof effect.

  Needless to say, the height and inner diameter of the cylindrical portion 38 are also determined by the tuning frequency of the orifice passage 50. Further, the shape of the cylindrical portion 38 is not limited to the illustrated one.

  Furthermore, the thickness and outer diameter of the movable plate portion 44 made of a rubber elastic body also depend on the amount of fluid flow caused by the elastic deformation of the movable plate portion 44, which is required to obtain the desired vibration-proofing effect. Can be arbitrarily set.

  Therefore, for example, as shown in FIG. 2, the entire plate-like partition portion 36 of the partition member 30 can be configured as a movable plate portion 44 made of a rubber elastic body. In other words, the entire partition member 30 may be composed of a rubber elastic body. In such a case, an advantage that the productivity of the partition member 30 can be advantageously improved is ensured as compared with the case where the partition member 30 is formed of an integrally vulcanized molded product of a rubber elastic body and a metal molded body.

  Further, depending on the required anti-vibration characteristics (for example, an anti-vibration effect for low-frequency vibration and a characteristic that requires only an anti-vibration effect for vibration in a higher frequency range), as shown in FIG. The movable plate portion 44 made of a rubber elastic body may be omitted from the member 30, and the entire plate-like partition portion 36 may be configured only by the support plate portion 42 made of a metal plate. In this case, for example, when tuning the size of the narrowed portion 52, the necessity of considering the fluid flow due to the deformation of the plate-like partition portion 36 (movable plate portion 44) is eliminated, and the tuning operation becomes easier. The advantage that it becomes becomes.

  In the case where at least the outer peripheral portion of the plate-like partition portion 36 is configured by the support plate portion 42, for example, a synthetic resin plate or the like may be used instead of the metal plate.

  Further, in the above-described embodiment, the entire cylindrical portion 38 is positioned in the pressure receiving chamber 32. However, the cylindrical portion 38 has at least a tip portion on one side where the protruding portion 40 is formed at the pressure receiving chamber. It suffices if it is located within 32. Therefore, for example, the cylindrical portion 38 extends upward from the upper surface of the plate-like partition portion 36 and extends downward from the portion positioned in the pressure receiving chamber 32 and the lower surface of the plate-like partition portion 36. Even if it is configured to have a portion positioned in the equilibrium chamber 34, there is no problem. In this case, the flow path length of the orifice passage 50 can be set in a wider range, and thus the degree of freedom in designing the tuning frequency of the orifice passage 50 can be advantageously increased.

  Further, as the rubber elastic body material constituting at least the cylindrical portion 38 and the protruding portion 40 of the partition member 30, for example, a self-lubricating rubber or the like is preferably used in addition to a general rubber material. As a result, generation of a rubbing sound or the like at the time of contact between the cylindrical portion 38 or the protruding portion 40 and the main rubber elastic body 14 can be effectively prevented.

  In addition, in the above-described embodiment, a specific example of the present invention applied to an engine mount for automobiles has been shown, but the present invention also includes a fluid-filled vibration isolator other than an engine mount installed in an automobile, Of course, it can be advantageously applied to any fluid-filled vibration isolator other than automobiles.

  In addition, although not enumerated one by one, the present invention can be carried out in a mode 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 a longitudinal section explanatory view showing one embodiment of a vibration isolator according to the present invention. It is a figure corresponding to FIG. 1 which shows another embodiment of the vibration isolator according to this invention. It is a figure corresponding to FIG. 1 which shows another embodiment of the vibration isolator according to this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 1st mounting bracket 12 2nd mounting bracket 14 Main body rubber elastic body 28 Diaphragm 30 Partition member 32 Pressure receiving chamber 34 Equilibrium chamber 36 Plate-shaped partition part 38 Cylindrical part 40 Projection part 42 Support plate part 44 Movable plate part 46 Through Hole 50 Orifice passage 52 Constriction

Claims (4)

The first mounting member and the second mounting member that are spaced apart from each other are connected by the main rubber elastic body interposed therebetween, and the partition member supported by the second mounting member is sandwiched between the first mounting member and the second mounting member. Thus, a pressure receiving portion in which a part of the wall portion is constituted by the main rubber elastic body on the first mounting member side, and internal pressure fluctuation is caused when vibration is input, and a predetermined incompressible fluid is sealed inside. While forming a chamber, on the side opposite to the pressure receiving chamber, a part of the wall portion is made of a flexible membrane, and volume change is allowed based on deformation of the flexible membrane, and a predetermined inside In the fluid-filled vibration isolator configured to form an equilibrium chamber in which the incompressible fluid is sealed, and further, an orifice passage configured to communicate the pressure receiving chamber and the equilibrium chamber with each other is provided.
A cylindrical portion made of a rubber elastic body, in which a tip portion on one side is located in the pressure receiving chamber and communicates with the pressure receiving chamber and the equilibrium chamber, is provided integrally with the partition member, and the orifice The passage is configured by the cylindrical portion, and a protruding portion that protrudes in a direction intersecting the axial direction is integrally formed at the tip portion on the one side of the cylindrical portion, and the leading end surface of the protruding portion and the A fluid-filled vibration isolator having a constricted portion provided between an inner wall surface of a pressure receiving chamber.   The partition member has a plate-like partition portion that contacts the incompressible fluid in the pressure-receiving chamber on one surface, and a plate-shaped partition portion that contacts the incompressible fluid in the equilibrium chamber on the other surface. The fluid filled type vibration damping device according to claim 1, wherein the cylindrical portion is integrally formed with the partition portion.   The fluid-filled type vibration damping device according to claim 2, wherein the plate-like partition portion is made of a rubber elastic body and can be elastically deformed by a fluid pressure difference between the pressure receiving chamber and the equilibrium chamber. . The fluid-filled vibration isolator according to any one of claims 1 to 3, wherein the entire partition member is made of a rubber elastic body.

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