JP4891295B2 - Liquid-filled vibration isolator - Google Patents

Description

  The present invention relates to a liquid-filled vibration isolator.

  Conventionally, as described in, for example, Patent Document 1 below, an upper fixture that is attached to a vibration generator such as an engine, a cylindrical lower fixture that is attached to a vehicle body frame, and these fixtures are connected. A vibration isolating base made of a rubber-like elastic material; a diaphragm made of a rubber film which is attached to the lower fixture and forms a liquid sealing chamber between the vibration isolating base; and the liquid sealing chamber on the side of the vibration isolating base. A partition body for partitioning the first liquid chamber and the second liquid chamber on the diaphragm side, and an orifice for communicating these liquid chambers are formed. The partition body is formed with an elastic partition film and an annular orifice for housing the elastic partition film. 2. Description of the Related Art There is known a liquid-filled vibration isolator that includes a member and a first lattice portion and a second lattice portion that restrict the amount of displacement of the elastic partition film from both sides of the film surface.

  In such a liquid filled type vibration isolator, when a large amplitude low frequency vibration occurs, the liquid flows through the orifice between the first liquid chamber and the second liquid chamber, and the vibration is attenuated by the liquid flow effect. Further, when high-frequency vibration with a small amplitude is generated, the elastic partition film is reciprocally deformed to absorb the liquid pressure in the first liquid chamber and reduce the vibration. According to the above-described conventional structure, an impact when the elastic partition membrane collides with the first lattice portion and the second lattice portion is transmitted to the lower fixture through the rigid orifice forming member, and from the lower fixture. There is a problem that noise is transmitted to the vehicle body frame to cause an abnormal noise in the vehicle interior.

  On the other hand, the following Patent Document 2 discloses a partition for partitioning the first liquid chamber and the second liquid chamber for the purpose of preventing abnormal noise due to impact from being transmitted to the vehicle interior without impairing the above-mentioned vibration isolation characteristics. It has been proposed to construct the body as follows. That is, the partition body is a pair of partitions that are connected to each other via an annular orifice forming member, a rubber wall that closes between the inner peripheral surfaces, and a connecting portion that penetrates the rubber wall and sandwiches the rubber wall in the axial direction. And a displacement amount in the axial direction of the pair of partition plates is regulated by the rubber wall.

  With such a configuration, the displacement amount of the pair of partition plates is regulated by the rubber wall, so that the vibration is attenuated by the liquid flow effect by the orifice with respect to the large amplitude vibration in the low frequency region, and the high frequency region. The vibration can be reduced by reducing the dynamic spring constant due to the reciprocating motion of the partition plate with respect to the minute amplitude vibration in the case. In addition, since the partition plate is supported by the rubber wall, it is possible to suppress transmission of abnormal noise into the vehicle interior.

On the other hand, in the liquid-filled vibration isolator described in Patent Document 2, the lower attachment includes a cylindrical fitting in which the vibration-proof base is vulcanized and a cup-like shape coupled to the lower end of the cylindrical fitting. And a bottom bracket, and is configured to be fixed to the vehicle body frame by the bottom bracket.
JP 2006-144806 A JP 2006-207672 A

  According to the partition plate configuration disclosed in Patent Document 2, it is possible to achieve both the damping performance in the low frequency range and the low dynamic spring in the high frequency range, but this requirement level has been further increased recently. . In response to this requirement, for example, when the rubber wall is made thin overall or the elastic modulus of the material constituting the rubber wall is lowered, the partition plate can be easily reciprocated with respect to high-frequency vibrations, and the dynamic spring constant is set. Can be reduced. On the other hand, however, the above measures impair the effect of restricting displacement of the partition plate by the rubber wall during low-frequency, large-amplitude vibration, and decrease the damping performance.

  On the other hand, in the lower fixture configuration disclosed in Patent Document 2, since the cylindrical bracket and the bottom bracket are configured as members that support the weight of the engine, the cylindrical bracket and the bottom bracket are relatively thick and have high strength. There is a problem that the material cost and the product weight increase correspondingly. In addition, since the cylindrical bracket and the bottom bracket that support the weight of the engine are configured so that the cylindrical bracket is stacked in series on the bottom bracket attached to the vehicle body frame, the liquid-filled vibration isolator on the vehicle body frame as a whole Overall height becomes high. As a result, a large load is applied to the cylindrical fitting and the bottom fitting against the lateral displacement. From this point also, it is necessary to use a relatively thick and high-strength material for the cylindrical fitting and the bottom fitting. As a result, material costs and product weight increase.

  The present invention has been made in view of the above points, and achieves both a higher level of damping performance improvement for low-frequency large-amplitude vibration and a reduction in dynamic spring constant for high-frequency fine-amplitude vibration than ever before. It is another object of the present invention to provide a liquid-filled vibration isolator capable of reducing the material cost and weight.

  The liquid-filled vibration isolator according to the present invention includes an upper fixture attached to the vibration generator, a cylindrical lower fixture attached to the vehicle body frame, and the upper fixture and the lower fixture connected to each other. An anti-vibration base made of a rubber-like elastic material, a diaphragm made of a rubber-like elastic film that is attached to the lower fixture and forms a liquid enclosure between the anti-vibration base, and the liquid enclosure chamber A partition body that partitions the first liquid chamber on the vibration-isolating base side and the second liquid chamber on the diaphragm side, and an orifice that allows the first liquid chamber and the second liquid chamber to communicate with each other are provided. The lower fixture includes an intermediate member to which the anti-vibration base is attached, and the liquid attached between the anti-vibration base and the diaphragm by being attached to the lower side of the intermediate member to which the diaphragm is attached. It consists of a diaphragm member that forms a sealing chamber and a stopper member that is coupled to the upper side of the intermediate member and exerts a stopper action between the upper fixture. The stopper member includes a cylindrical stopper restricting portion that surrounds the upper fixture and restricts displacement of the upper fixture, and a stopper fixing portion that projects radially outward from the lower end of the stopper restricting portion. The stopper fixing portion is fixed to the vehicle body frame, so that at least the diaphragm member is embedded in the vehicle body frame. In addition, the partition body is an elastic wall made of a rubber-like elastic material that is provided inside the lower fixture and forms a gap between the annular orifice forming member and the inner peripheral surface of the orifice forming member. And a pair of partition plates that are connected to each other via a connecting portion that penetrates the radial center of the elastic wall and sandwiches the elastic wall in the axial direction of the elastic wall. The elastic wall includes a boundary line portion extending in the circumferential direction, a thin wall portion having a wall surface arranged to face and separate from the plate surface of the partition plate on the inner peripheral side of the boundary line portion, On the outer peripheral side of the boundary line portion, a thick wall is formed with a stepped thickness with respect to the thin wall portion with the boundary line portion as a boundary, and the radially outer side between the partition plate and the plate surface. And a thick wall portion having a wall surface that forms a gradually widening gap.

  According to the above configuration, the elastic wall is partitioned and formed by the boundary line portion into the thin wall portion on the inner peripheral side and the thick wall portion on the outer peripheral side, and the thin wall portion on the inner peripheral side is between the partition plate. It is formed away from the partition plate so as to ensure a predetermined clearance. For this reason, the thin wall portion serves as a low-rigidity portion and the partition plate can be easily reciprocated in the axial direction with respect to fine amplitude vibration in a high frequency range, and the dynamic spring constant can be reduced. On the other hand, for large-amplitude vibration in the low frequency range, the thick wall portion on the outer peripheral side disposed opposite to the partition plate through a gap gradually widening toward the radially outer side is a partition plate as a high-rigidity portion. The reciprocating displacement can be effectively regulated. Therefore, the improvement of the damping performance for the low frequency large amplitude vibration and the reduction of the dynamic spring constant for the high frequency fine amplitude vibration can be achieved at a high level.

  In addition, since the lower fixture is configured as described above and is fixed to the vehicle body frame by the stopper fixing portion provided on the stopper member, the stopper member takes on the rigidity strength for supporting the weight of the vibration generating body. The rigidity strength required for the intermediate member and the diaphragm member can be reduced. Therefore, the thickness of the intermediate member and the diaphragm member can be reduced and the material can be changed to a low-strength material, so that the material cost can be reduced and the weight can be reduced. Also, by fixing the body frame to the body frame with a stopper member, at least the diaphragm member is embedded in the body frame, thereby reducing the mounting height of the liquid-filled vibration isolator from the body frame mounting surface. be able to. Therefore, it is easy to ensure the rigidity and strength of the entire vibration generator support structure as compared with the conventional structure in which the mounting height from the vehicle body frame is high. Moreover, the rigidity strength required to support the lateral load can be reduced. As a result, the thickness of the constituent members including the stopper member can be reduced and the material can be changed to a low-strength material. As a result, the overall weight reduction and material cost of the liquid-filled vibration isolator can be reduced. Can be planned.

  In the above configuration, the boundary line portion may be formed thinner than the thin wall portion by a groove extending in the circumferential direction provided on at least one wall surface of the elastic wall.

  In this way, by forming the boundary line portion between the thin wall portion and the thick wall portion as a low-rigidity portion that is thinner than the thin wall portion, the partition plate is arranged in the axial direction against high-frequency fine amplitude vibration. By making it easier to reciprocate, the dynamic spring constant can be reduced.

  In the above configuration, the distance between the wall surface of the thin wall portion and the plate surface of the partition plate facing the wall surface is the same as the wall surface of the thick wall portion and the plate surface of the partition plate facing the wall surface. It may be set larger than the maximum dimension of the gap.

  By setting in this way, the reciprocating range of the partition plate is determined by the gap in the thick wall portion on the outer peripheral side, and the thin wall portion on the inner peripheral side is prevented from contacting the partition plate even during large amplitude vibration. be able to. Therefore, it is possible to prevent abnormal noise due to the collision between the thin wall portion on the inner peripheral side and the partition plate during large amplitude vibration.

  In the above configuration, the thick wall portion contacts the plate surface of the partition plate at the inner peripheral edge, and the wall surface of the thick wall portion is between the plate surface of the partition plate on the outer peripheral side of the contact portion. The gap may be formed so as to gradually increase toward the radially outer side.

  In this way, by causing the inner peripheral edge of the thick wall portion to be in contact with the partition plate, it is possible to prevent the generation of noise due to the collision between the two. Further, since only the inner peripheral edge is in contact, the reciprocating displacement of the partition plate by the thin wall portion at the time of high frequency fine amplitude is not hindered. In addition, by providing the gap that gradually widens on the outer peripheral side of the contact portion, the contact area between the thick wall portion and the partition plate increases sequentially and smoothly from the inner peripheral side to the outer peripheral side during large amplitude vibration. The effect of restricting the displacement of the partition plate can be enhanced without causing abnormal noise.

  In the above-described configuration, the wall surface of the thick wall portion and the plate surface of the partition plate facing the wall surface are each in the form of an inclined surface positioned radially outward in the axial direction of the elastic wall. The thin wall portion may be formed with a constant thickness in the radial direction.

  Thereby, the said displacement control effect of the partition plate in large amplitude vibration and the said reciprocating displacement effect of the partition plate at the time of a high frequency fine amplitude vibration can be exhibited more effectively.

  In the above-described configuration, the outer peripheral portion of the elastic wall that is bonded and fixed to the inner peripheral surface of the orifice forming member protrudes outward in the axial direction with respect to the inclined wall surface of the thick wall portion. A raised portion that increases the rigidity of the outer peripheral portion of the elastic wall may be provided.

  By providing such a raised portion, it is possible to increase the rigidity of the outer peripheral portion of the elastic wall and further enhance the effect of restricting the displacement of the partition plate during large amplitude vibration.

  In the above configuration, even if a convex portion that protrudes radially inward and increases the rigidity of the outer peripheral portion of the elastic wall is provided on the inner peripheral surface of the orifice forming member to which the outer peripheral portion of the elastic wall is bonded and fixed. Good.

  By providing such a convex part, the rigidity of the outer peripheral part of an elastic wall can be raised and the displacement control effect of a partition plate at the time of a large amplitude vibration can further be heightened.

  In the above configuration, the outer peripheral portion of the elastic wall that is bonded and fixed to the inner peripheral surface of the orifice forming member has the inclined surface shape of the thick wall portion on the wall surface on the first liquid chamber side of the elastic wall. A raised portion that protrudes toward the first liquid chamber side with respect to the wall surface is provided, and a tip of the raised portion is provided so as to be positioned closer to the first liquid chamber side than the first liquid chamber side end of the orifice forming member. Good. In addition, a convex portion projecting radially inward is provided on the inner peripheral surface of the orifice forming member to which the outer peripheral portion of the elastic wall is bonded and fixed at the base portion of the elastic wall on the second liquid chamber side. The side surface of the convex portion on the second liquid chamber side is formed on a straight surface orthogonal to the axial direction of the elastic wall, and the side surface of the convex portion on the second liquid chamber side is formed when the elastic wall is formed. It may be a pressing surface in the axial direction with respect to the molding die.

  By providing such a raised part and a convex part, the rigidity of the outer peripheral part of an elastic wall can be raised and the displacement control effect of the partition plate at the time of a large amplitude vibration can further be heightened. Further, on the first liquid chamber side of the partition body, a protruding portion is provided on the elastic wall as a means for increasing the rigidity, and since this protruding portion is made of a rubber-like elastic material, the vibration-proof base is excessively displaced. Even when it hits the raised portion, it is possible to prevent the vibration-proof substrate from being damaged. Further, on the second liquid chamber side of the partition, a convex portion is provided on the inner peripheral surface of the orifice forming member as a means for increasing the rigidity, and the side surface of the convex portion on the second liquid chamber side is defined as the axial direction. It is formed on an orthogonal straight surface. Therefore, at the time of molding the elastic wall, the mold can be pressed against the side surface of the straight convex part to seal the rubber-like elastic material so that it does not leak out of the cavity, thereby suppressing the generation of burrs. Can do.

  In the above configuration, the intermediate member includes a vibration isolating base connecting portion to which the vibration isolating base is connected, and an intermediate overhanging portion that protrudes radially outward from the vibration isolating base connecting portion. Also good. Further, the diaphragm member has a bottom portion having an opening closed by the diaphragm, a cylindrical portion erected from an outer edge of the bottom portion, and a flange shape radially outward from an upper end of the cylindrical portion. The diaphragm side overhanging part overlaid on the lower surface of the intermediate overhanging part, and a pair of bent pieces standing from the outer edge of the diaphragm side overhanging part and sandwiching the cylindrical part Good. Further, the stopper member includes a stopper-side protruding portion that protrudes radially outward from the lower end of the stopper regulating portion in a flange shape and is superimposed on the upper surface of the intermediate protruding portion, and the stopper fixing portion is A pair of protrusions projecting radially outward from the outer edge of the stopper-side overhanging portion and located between the stopper restricting portions may be provided. Further, the intermediate overhanging portion is sandwiched between the diaphragm side overhanging portion and the stopper side overhanging portion, and the folded piece of the diaphragm member is folded back onto the upper surface of the stopper side overhanging portion, The stopper member, the intermediate member, and the diaphragm member may be combined.

  Since the stopper member, the intermediate member, and the diaphragm member are combined and integrated using the bent pieces provided on the diaphragm member in this manner, the work efficiency during manufacturing can be improved. That is, in the configuration that is fixed to the vehicle body frame using the stopper member as described above, since the thickness of the stopper member is thick, the diaphragm member can be formed thinner than the thickness of the stopper member. A bending operation can be easily performed by forming a bent piece on the diaphragm member and bending the bent piece.

  In the above-described configuration, a diaphragm-side buffer layer made of a rubber-like elastic material connected to the diaphragm is provided on the upper surface of the bottom portion of the diaphragm member and the inner peripheral surface of the cylindrical portion, and the protection member of the intermediate member is covered. An intermediate member-side buffer layer made of a rubber-like elastic material connected to the vibration-isolating substrate is covered at the lower end of the vibration-substrate connecting portion, and the orifice-forming member of the partition is covered with the diaphragm-side buffer that covers the tubular portion. While being fitted to the inner peripheral surface of the layer, the intermediate member side buffer layer and the diaphragm side buffer layer covering the bottom may be sandwiched.

  Thereby, the said partition body can be supported inside the said lower attachment tool through only a rubber-like elastic material. Therefore, in combination with the structure of the partition body itself in which the pair of partition plates are supported by elastic walls, it is possible to suppress transmission of abnormal noise from the partition body to the vehicle interior.

  As described above, according to the present invention, it is possible to improve the damping performance for low-frequency large-amplitude vibration and reduce the dynamic spring constant for high-frequency fine-amplitude vibration at a high level, reduce the material cost, and reduce the weight. Can be achieved.

  Hereinafter, a liquid-filled vibration isolator according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a longitudinal sectional view of a liquid filled type vibration damping device 10 according to an embodiment, FIG. 2 is a plan view thereof, and FIG. 3 is a side view thereof. The vibration isolator 10 includes an upper fixture 12 that is attached to an engine that is a vibration generator, a cylindrical lower fixture 14 that is attached to a vehicle body frame, and a vibration isolating base 16 that is formed of a rubber elastic material that connects them. And a diaphragm 20 made of a rubber elastic film, which is attached to the lower fixture 14 and forms a liquid enclosure chamber 18 between the antivibration substrate 16 and the liquid enclosure chamber 18 in the first liquid chamber on the vibration isolation substrate 16 side. This is a liquid-filled automobile engine mount comprising a partition body 22 for partitioning 18A and a second liquid chamber 18B on the diaphragm 20 side, and an orifice 23 for communicating the first liquid chamber 18A and the second liquid chamber 18B. .

  The upper fixture 12 is a cylindrical metal fitting disposed above the shaft core portion of the lower fixture 14 that is arranged with the axial direction X directed in the vertical direction, and protrudes radially outward Ko at the lower end. A stopper flange 24 is formed. A mounting bolt 25 protrudes from the upper surface and is configured to be attached to the engine side via the bolt 25.

  The lower fixture 14 includes an intermediate member 26 to which the vibration isolation base 16 is attached, a diaphragm member 27 to which the diaphragm 20 is attached, and a stopper member 28 that exerts a stopper action between the upper fixture 12. It is a metal member.

  The intermediate member 26 has a cylindrical vibration-isolating base connecting portion 29 that is connected in a state in which the outer periphery of the lower end of the vibration-isolating base 16 is embedded, and is stretched in a flange shape from the vibration-isolating base connecting portion 29 to the radially outward Ko. It consists of an intermediate overhang part 30 to be put out. The intermediate projecting portion 30 projects from the upper end opening edge of the vibration isolating base connecting portion 29 over the entire periphery thereof, and is formed in a ring plate shape having a circular outer shape.

  The anti-vibration base connecting portion 29 includes a tapered inclined cylindrical portion 29A extending obliquely inward in the radial direction Ki from the inner edge of the intermediate overhang portion 30, and a straight downward from the lower end of the inclined cylindrical portion 29A. A straight cylindrical portion 29B having a short cylindrical shape extending in a shape. An intermediate member-side buffer layer 31 made of a rubber elastic material continuous from the vibration isolating base 16 is covered on the inner periphery and the lower end of the vibration isolating base connecting portion 29. The buffer layer 31 is also provided so as to wrap around the outer peripheral surface side of the vibration-proof base connecting portion 29.

  The diaphragm member 27 is a member that forms the liquid enclosure chamber 18 between the vibration isolating base 16 and the diaphragm 20 by being coupled to the lower side of the intermediate member 26. The diaphragm member 27 includes a bottom portion 32 having an opening portion 32A formed in the center, a cylindrical portion 33 erected upward from the outer edge of the bottom portion 32, and a radially outer side Ko from the upper end of the cylindrical portion 33. A diaphragm side projecting portion 34 projecting in a flange shape and a bent piece 35 erected upward from the outer edge of the diaphragm side projecting portion 34.

  The bottom 32 is provided in a state in which the opening 32A is closed by the diaphragm 20 by vulcanizing and bonding the outer periphery of the diaphragm 20 to the inner periphery of the opening 32A. The diaphragm 20 is formed in a cross-sectional wave shape so as to be able to bend and deform.

  The cylindrical portion 33 extends from the outer edge of the bottom portion 32 in a straight cylindrical shape to the short cylindrical shape 33A, and extends from the upper end of the straight cylindrical portion 33A upward in the radial direction Ko. It consists of an inversely tapered inclined cylinder part 33B.

  On the upper surface of the bottom portion 32 and the inner peripheral surface of the cylindrical portion 33, a diaphragm side buffer layer 36 made of a rubber elastic material continuous from the diaphragm 20 is covered.

  The diaphragm side overhanging portion 34 is a portion that is overlapped with the lower surface of the intermediate overhanging portion 30, and extends over the entire periphery from the upper end opening edge of the cylindrical portion 33, and is formed in a ring plate shape with a circular outer shape. .

  As shown in FIGS. 2 and 3, the bent pieces 35 are provided at two outer edge portions opposed to each other in the circumferential direction C of the diaphragm side projecting portion 34 so as to be located with the cylindrical portion 33 interposed therebetween. It has been.

  The stopper member 28 is a member coupled to the upper side of the intermediate member 26, and includes a cylindrical stopper regulating portion 37 that surrounds the upper fixture 12 and regulates its displacement, and a radial direction from the lower end of the stopper regulating portion 37. A stopper overhanging portion 38 that projects outwardly in a flange shape and a pair of stopper fixing portions 39 that are located from the outer edge of the stopper overhanging portion 38 to the radially outward Ko and sandwich the stopper restricting portion 37 therebetween.

  The stopper restricting portion 37 surrounds the outer periphery of the stopper flange 24 of the upper fixture 12 at a predetermined interval, and includes a cylindrical first stopper portion 37A that restricts the relative displacement of the upper fixture 12 in the horizontal direction, and a first stopper portion 37A. A second stopper portion 37B that extends in the form of an inward flange from the upper end of the stopper portion 37A and is positioned above the stopper flange 24 at a predetermined interval and restricts the relative displacement of the upper fixture 12 upward. And comprising. More specifically, in this example, an inversely tapered inclined cylindrical portion 37C extending from the lower end of the straight cylindrical first stopper portion 37A to be inclined downward in the radial direction Ko is provided. The stopper portion 37A is connected to the stopper overhanging portion 38 through the inclined cylindrical portion 37C.

  A stopper buffer layer 40 made of a rubber elastic material continuous from the vibration isolation base 16 is covered on the outer peripheral surface and the upper surface of the stopper flange 24. Accordingly, the stopper restricting portion 37 is configured to ensure a predetermined interval (stopper clearance) with the stopper buffer layer 40.

  Here, FIG. 1 shows a state in which the engine load is not applied. When the engine load is applied, as shown in FIG. 11, the upper fixture 12 is relatively displaced downward, and a predetermined stopper clearance is ensured between the upper stopper 12 and the second stopper portion 37B. In addition, as shown in FIG. 11, even when the engine load is applied, the first stopper portion 37A is positioned above and below the outer peripheral surface of the stopper flange 24 (specifically, the outer peripheral surface of the stopper buffer layer 40 covering this). The length of the first stopper portion 37A in the axial direction is set so as to face each other over the entire direction. As a result, when there is excessive horizontal displacement, the first stopper portion 37A is in contact with the outer peripheral surface of the stopper flange 24 over the entire surface in the vertical direction so that a good stopper action is exhibited. Has been.

  The stopper overhanging portion 38 is a portion that is overlaid on the upper surface of the intermediate overhanging portion 30, and extends over the entire periphery from the lower end opening edge of the stopper regulating portion 37, and is formed in a ring plate shape with a circular outer shape.

  The stopper fixing portion 39 is formed so as to project radially outward from two locations facing each other at 180 ° on the outer peripheral edge of the stopper projecting portion 38, and is formed in a trapezoidal shape in plan view as shown in FIG. Yes. Specifically, the stopper fixing portions 39 are provided to face each other in the diameter direction orthogonal to the facing direction of the pair of bent pieces 35 of the diaphragm member 27.

  The pair of stopper fixing portions 39 are provided with mounting bolts 41 projecting downward, respectively, and are configured to be fastened and fixed to the upper surface of the vehicle body frame 102 by the mounting bolts 41 as shown in FIG. ing. Accordingly, at least the diaphragm member 27 (here, the diaphragm member 27 and the intermediate member 26) is configured to be attached in a state of being embedded in the vehicle body frame 102.

  The lower fixture 14 composed of the three members described above sandwiches the intermediate overhang 30 between the diaphragm side overhang 34 and the stopper overhang 38, and a pair of bent pieces 35 of the diaphragm member 27. The stopper member 28, the intermediate member 26, and the diaphragm member 27 are assembled together by being folded and fixed to the upper surface of the stopper side overhanging portion 38, respectively.

  Reference numeral 42 denotes a disk-like stopper rubber member disposed on the upper surface of the stopper restricting portion 37 of the stopper member 28. The stopper rubber member 42 is disposed between the upper surface of the second stopper portion 37B of the stopper restricting portion 36 and the bracket 104 on the engine 100 side (see FIG. 11), and reduces the impact caused by the collision between the two. Radial grooves 43 that extend radially are provided on the upper surface of the stopper rubber member 42 (see FIG. 2), and are configured to reduce the impact sound caused by the collision with the bracket 104.

  The anti-vibration base 16 is formed in a substantially umbrella shape, and its upper end is vulcanized and bonded to the upper fixture 12 and its lower end is vulcanized and bonded to the intermediate member 26 of the lower fixture 14. The diaphragm 20 is provided so as to face the lower surface of the antivibration base 16 in the axial direction X, and the liquid sealing chamber 18 is formed therebetween.

  As described above, the liquid enclosure chamber 18 is divided into the first liquid chamber 18A as the main liquid chamber in which the vibration isolating substrate 16 forms part of the chamber wall and the sub-liquid in which the diaphragm 20 forms part of the chamber wall. The chamber is partitioned into a second liquid chamber 18B as a chamber, and both the liquid chambers 18A and 18B are communicated with each other via an orifice 23 as a throttle channel.

  As shown in FIGS. 1 and 4, the partition 22 includes an annular orifice forming member 44 provided inside the lower fixture 14 and an outer peripheral portion 46 </ b> A added to the inner peripheral surface 44 </ b> A of the orifice forming member 44. It consists of an elastic wall 46 made of a rubber elastic body that is glued and sealed between the inner peripheral surfaces 44A, and a pair of upper and lower partition plates 48 and 50 that sandwich the elastic wall 46 in the axial direction X thereof.

  The orifice forming member 44 is fitted on the inner peripheral surface of the diaphragm side buffer layer 36 that covers the tubular portion 33 of the diaphragm member 27, and the upper surface of the diaphragm side buffer layer 36 that covers the bottom portion 32 of the diaphragm member 27. And the lower surface of the intermediate member-side buffer layer 31, the partition 22 is supported on the inner side of the lower attachment 14 via only a rubber-like elastic material.

  The orifice forming member 44 is a member made of a rigid body that forms the orifice 23 that extends in the circumferential direction C (see FIG. 7) between the orifice forming member 44 and the cylindrical portion 33 of the diaphragm member 27. More specifically, the orifice forming member 44 includes a cylindrical portion 44B disposed coaxially with the lower fixture 14, and a recess opened outward in a U-shaped cross section on the outer peripheral side of the cylindrical portion 44B. A groove 44C. The inner peripheral surface of the cylindrical portion 44B is the inner peripheral surface 44A. The orifice 23 is formed between the cylindrical portion 33 of the diaphragm member 27 by the recessed groove portion 44C.

  In FIG. 7, reference numeral 52 denotes a first opening for communicating the orifice 23 and the first liquid chamber 18A, and reference numeral 54 denotes a second opening for communicating the orifice 23 and the second liquid chamber 18B. It is provided on the forming member 44.

  The elastic wall 46 has a circular shape in plan view, and its outer peripheral portion 46A is vulcanized and bonded to the inner peripheral surface 44A of the cylindrical portion 44B of the orifice forming member 44 as shown in FIG. The elastic wall 46 includes a circular through hole 56 that penetrates in the axial direction X at the radial center, and annular ridges 58 that project in the axial direction X are provided on both front and back sides around the through hole 56. It has been.

  As shown in FIG. 4, the pair of partition plates 48 and 50 are connected to each other via a columnar connecting portion 60 that passes through the through hole 56, and are integrally formed by a rigid body such as a resin material. One (upper) partition plate 48 of them constitutes a part of the chamber wall of the first liquid chamber 18A, that is, is arranged facing the first liquid chamber 18A. The other (lower) partition plate 50 constitutes a part of the chamber wall of the second liquid chamber 18B, that is, is arranged facing the second liquid chamber 18B. The displacement amount in the axial direction X of the pair of partition plates 48 and 50 is restricted by the elastic wall 46.

  The connecting portion 60 is configured by fixing the tip end surfaces of columnar connecting convex portions 60A provided at the center portions of the upper and lower partition plates 48 and 50 by ultrasonic welding or the like. Around the connecting portion 60, annular grooves 62 are provided in which the upper and lower ridges 58 of the elastic wall 46 are fitted. Further, a circular pinching protrusion 63 is provided around the annular groove 62 so as to protrude in the axial direction X and hold the elastic wall 46 from both the front and back sides.

  The pair of partition plates 48 and 50 are formed to have a smaller outer shape than the elastic wall 46 in plan view (see FIGS. 4 and 7). That is, the outer peripheral edges 48A, 50A of the partition plates 48, 50 are terminated on the radially inner side Ki side of the inner peripheral surface 44A of the orifice forming member 44 where the outer peripheral edge of the elastic wall 46 is located.

  As shown in FIGS. 6 and 8, the elastic wall 46 includes a boundary line portion 64 extending in the circumferential direction C, a thin wall portion 66 provided on the inner peripheral side of the boundary line portion 64, and an outer peripheral side of the boundary line portion 64. And a thick wall 68 provided on the wall.

  The boundary line portion 64 is a ring-shaped boundary portion that divides the thin wall portion 66 and the thick wall portion 68. In this example, the boundary line portion 64 is approximately between the connecting portion 60 and the orifice forming member 44 in the radial direction K. The center position is set (see FIG. 4). In addition, the boundary line portion 64 is a concave groove 70 extending in the circumferential direction C provided on both the front and back wall surfaces of the elastic wall 46 (that is, the wall surface on the first liquid chamber 18A side and the wall surface on the second liquid chamber 18B side). Thus, it is formed as a low rigidity portion that is thinner than the thin wall portion 66 on the inner peripheral side. The concave groove 70 is formed in a circular shape in plan view extending continuously over the entire circumference in the circumferential direction C.

  The thin wall portion 66 is a ring-shaped elastic wall portion adjacent to the inner peripheral side of the boundary line portion 64 as shown in FIG. 8, and between the pair of partition plates 48 and 50 as shown in FIG. Are spaced apart from each other in the axial direction X. That is, the front and back wall surfaces 66A of the thin wall portion 66 are disposed to face and separate from the plate surfaces 48B and 50B of the partition plates 48 and 50 (see FIG. 5). On both sides, a predetermined space 72 filled with liquid is secured between the partition plates 48 and 50.

  As shown in FIG. 6, the thin wall portion 66 is formed in a flat plate shape having a constant thickness in the radial direction K. As shown in FIG. 5, the inner peripheral edge portion of the thin wall portion 66 is held in a state compressed in the axial direction X by the pressing protrusions 63 and 63 of the pair of partition plates 48 and 50. Therefore, the predetermined space 72 is secured between the thin wall portion 66 and the partition plates 48 and 50 on the radially outer side Ko of the sandwiched inner peripheral edge portion. Further, in this portion, the first plate surfaces 48B, 50B of the partition plates 48, 50 facing the thin wall portion 66 are formed in a straight surface shape orthogonal to the axial direction X, so that the space 72 is formed in the radial direction K. Are formed at regular intervals.

  On the other hand, as shown in FIG. 6, the thick wall portion 68 is thickened in a stepped manner on the outer peripheral side of the boundary line portion 64 with respect to the thin wall portion 66 with the boundary line portion 64 as a boundary. Is formed. That is, the thick wall portion 68 is formed in a thick shape outside the discontinuous portion by being discontinuously thickened so that the wall thickness suddenly changes from the boundary line portion 64. As shown in FIG. 8, the thick wall portion 68 is a ring-shaped elastic wall portion adjacent to the outer peripheral side of the boundary line portion 64.

  As shown in FIG. 5, the thick wall portion 68 has a wall surface 68 </ b> A that forms a gap 74 that gradually increases toward the radially outward Ko side between the second plate surfaces 48 </ b> C and 50 </ b> C of the partition plates 48 and 50. It is formed on both the front and back sides. Specifically, the thick wall portion 68 is in contact with the second plate surfaces 48C and 50C of the upper and lower partition plates 48 and 50 at the inner peripheral edge thereof, and on the outer peripheral side of the contact portion 76, the thick wall wall 68 is provided. The wall surface 68A of the portion 68 forms the gap 74 that gradually increases toward the radially outward Ko side between the second plate surfaces 48C and 50C of the partition plates 48 and 50 facing the wall surface 68A. The contact portion 76 is preferably configured to contact the thick wall portion 68 without being pressed in the axial direction X, and is provided in a line contact state over the entire circumference in the circumferential direction C.

  Further, the wall surface 68A of the thick wall portion 68 and the second plate surfaces 48C and 50C of the partition plates 48 and 50 facing the wall surface 68A are closer to the axially outward Xo side of the elastic wall 46 toward the radially outward Ko side. It is formed in the shape of an inclined surface. Therefore, the thick wall portion 68 is gradually formed thicker toward the radially outward Ko side. In addition, the slopes of the inclined surfaces of the second plate surfaces 48C and 50C of the partition plates 48 and 50 are set to be slightly larger than the inclined surfaces of the wall surface 68A of the thick wall portion 68. The gap 74 is formed so as to gradually become wider toward the side Ko.

  As shown in FIG. 5, the distance between the wall surface 66 </ b> A of the thin wall portion 66 and the first plate surfaces 48 </ b> B and 50 </ b> B of the partition plates 48 and 50 facing the wall surface 66 </ b> A is the wall surface of the thick wall portion 68. 68A and the second plate surfaces 48C and 50C of the partition plates 48 and 50 opposed thereto, which are larger than the maximum dimension of the gap 74 (the gap in the axial direction X of the gap 74 at the radially outer end). Is set. Thereby, even when a large amplitude vibration is input, the thin wall portion 66 does not contact the partition plates 48 and 50, and the range of movement of the partition plates 48 and 50 is only the gap 74 in the thick wall portion 68 on the outer peripheral side. It is comprised so that it may be prescribed | regulated.

  Further, in order to increase the rigidity of the base portion of the elastic wall 46 with respect to the orifice forming member 44 and enhance the displacement regulating effect of the pair of partition plates 48 and 50 at the time of low frequency and large amplitude, the following configuration is adopted. Yes.

  That is, first, the outer peripheral portion 46A of the elastic wall 46 bonded and fixed to the inner peripheral surface 44A of the orifice forming member 44 has an inclined surface shape of the thick wall portion 68 on the wall surface on the first liquid chamber 18A side. A raised portion 78 is provided that protrudes toward the axially outward Xo side of the wall surface 68A, that is, toward the first liquid chamber 18A. As shown in FIG. 8, the raised portion 78 has an annular shape extending over the entire circumferential direction C. Further, as shown in FIG. 5, the protruding portion 78 has a distal end (that is, an outer end in the axial direction X) 78 </ b> A that is closer to the first liquid chamber 18 </ b> A than the first liquid chamber side end 44 </ b> D of the orifice forming member 44. Located on the side. Further, the raised portion 78 is formed so as to protrude beyond the upper surface of the partition plate 48 on the first liquid chamber 18A side toward the axial direction outward Xo side.

  Second, the inner peripheral surface 44A of the orifice forming member 44 to which the outer peripheral portion 46A of the elastic wall 46 is bonded and fixed protrudes radially inward Ki at the base portion of the elastic wall 46 on the second liquid chamber 18B side. A convex portion 80 is provided. As shown in FIG. 5, the convex portion 80 is formed in an inclined surface shape in which the side surface 80 </ b> A on the axial direction X center side of the elastic wall 46 is positioned on the radially inward Ki side toward the axial direction outward Xo side. In addition, the side surface 80B on the second liquid chamber 18B side is formed on a straight surface orthogonal to the axial direction X of the elastic wall 46. The side surface 80B on the second liquid chamber side having a straight surface is a portion used as a pressing surface in the axial direction X of the mold when the elastic wall 46 described later is molded. Therefore, the base portion of the second liquid chamber 18B of the elastic wall 46 is formed in a state in which the convex portion 80 is embedded so as to cover the top surface 80C excluding the side surface 80B and the side surface 80A on the center side.

  Reference numeral 82 is an air vent hole provided in the partition plates 48 and 50 and penetrating in the axial direction X. As shown in FIG. 7, a plurality (in this case, four) are provided in the circumferential direction C of the partition plates 48 and 50. ) Are distributed. The air vent hole 82 is provided so as to communicate the space 72 between the thin wall portion 66 and the partition plates 48 and 50 to the first liquid chamber 18A or the second liquid chamber 18B. When the vibration isolator 10 is manufactured, the space 72 is evacuated and used to fill the space 72 with a liquid.

  The liquid-filled vibration isolator 10 can be manufactured as follows.

  First, when the partition body 40 is manufactured, the elastic wall 46 is vulcanized and formed on the orifice forming member 44. At the time of vulcanization molding, as shown in FIG. 9, the first mold 92 for molding the wall surface of the elastic wall 46 on the first liquid chamber 18A side and the second wall for forming the wall surface of the second liquid chamber 18B of the elastic wall 46 are formed. A rubber material is injected into a cavity 96 formed between the first die 92 and the second die 94 using a molding die 90 composed of the die 94, and the elastic wall 46 is vulcanized.

  At this time, in order to prevent rubber burrs from being generated at the base portion of the elastic wall 46 to the orifice forming member 44, the first mold 92 is attached to the first portion 92 of the orifice forming member 44 at the base portion of the elastic wall 46 on the first liquid chamber 18 </ b> A side. By pressing in the axial direction X against the one liquid chamber side end 44D, leakage of the rubber material from the cavity 96 is prevented.

  On the other hand, at the base portion of the elastic wall 46 on the second liquid chamber 18B side, the step surface 94A of the second mold 94 is axially oriented with respect to the straight side surface 80B of the convex portion 80 provided on the orifice forming member 44. Press against X. Thereby, the leakage of the rubber material from this portion is prevented, and the generation of rubber burrs can be suppressed. Here, if the elastic wall is bonded and fixed to the flat inner peripheral surface of the orifice forming member without providing such a convex portion as in the above-mentioned Patent Document 2, the first inner peripheral surface of the orifice forming member 44 is fixed. It is necessary to seal the rubber material by bringing the outer peripheral surface of the type 2 94 into close contact. However, due to the dimensional tolerance of the orifice forming member 44, it is difficult to seal the second die 94 with no gap, and rubber burrs are likely to occur. On the other hand, by using the side surface 80B of the convex portion 80 as the pressing surface in the axial direction X as in the present embodiment, rubber burrs can be prevented without such a problem, which is advantageous.

  After the elastic wall 46 is vulcanized and molded in this way, as shown in FIG. 6, the partition plates 48 and 50 are sandwiched from both the front and back sides of the elastic wall 46, and the connecting portion 60 is fixed by ultrasonic welding or the like. The partition body 40 shown in FIG. 4 is obtained.

  Next, the partition body 40, a vulcanized molded part of the lower mounting member 12, the intermediate member 26, and the vibration isolating base 16 obtained by separately vulcanizing molding, and a vulcanized molding of the diaphragm member 27 and the diaphragm 20 are obtained. Using the components, the partition body 40 is inserted inside the diaphragm member 27 in the liquid, and the intermediate member 26 is assembled to form the liquid enclosure chamber 18. In that case, since the air vent holes 82 are provided in the partition plates 48 and 50, the air can be extracted from the space 72 between the thin wall portion 66 and the partition plates 48 and 50 to fill the space 72 with the liquid. And the performance of the partition body 40 can be ensured.

  After the partition body 40 is incorporated in this way to form the liquid enclosure chamber 18, the liquid fixture chamber 18 is taken out from the liquid, covered with the stopper member 28, and the bent piece 35 of the diaphragm member 27 is bent, so that the lower fixture 14 is removed. Connect together. Thereby, the liquid-filled vibration isolator 10 can be manufactured.

  The liquid-filled vibration isolator 10 thus obtained is interposed between the bracket 104 on the engine 100 side and the vehicle body frame 102 as shown in FIGS. Specifically, the upper fixture 12 is fastened and fixed to the lower end portion of the bracket 104 connected to the engine 100 via the attachment bolt 25. Further, the lower attachment 14 is fastened and fixed to the vehicle body frame 102 via attachment bolts 41.

  As shown in FIG. 11, the vehicle body frame 102 is provided with a circular opening 106, and a portion below the stopper fixing portion 39 of the lower attachment 14 is embedded in the opening 106. In this state, the stopper fixing portion 39 is fixed to the upper surface of the vehicle body frame 102 using a pair of mounting bolts 41.

  At this time, in this embodiment, as shown in FIG. 10, the facing direction L of the pair of mounting bolts 41 disposed in the stopper fixing portion 39 is arranged so as to be parallel to the left-right direction M of the vehicle. . Therefore, the rigidity strength of the lower fixture 14 can be efficiently ensured with respect to the left-right direction M of the vehicle. Therefore, the stopper action by the stopper member 28 in the left-right direction M of the vehicle can be surely exhibited, and the durability of the stopper member 28 can be improved. On the contrary, the facing direction L of the pair of mounting bolts 41 can be arranged so as to be parallel to the longitudinal direction N of the vehicle. The rigidity strength of the fixture 14 can be efficiently ensured, and the stopper action in the vehicle front-rear direction N can be reliably exhibited, and the durability of the stopper member 28 can be improved.

  In the liquid-filled vibration isolator 10 according to the present embodiment, when a small amplitude vibration in a high frequency region occurs, the pair of partition plates 48 and 50 are reciprocated together to form the first liquid chamber 18A. By absorbing the hydraulic pressure, vibration can be reduced. In particular, in the present embodiment, the elastic wall 46 is partitioned and formed by the boundary line portion 64 into a thin wall portion 66 on the inner peripheral side and a thick wall portion 68 on the outer peripheral side, and the thin wall portion on the inner peripheral side. 66, the partition plates 48 and 50 are spaced apart from the partition plates 48 and 50 so as to ensure a predetermined space 72. Therefore, with respect to high-frequency fine amplitude vibration, the partition wall 48, 50 can be easily reciprocated in the axial direction X with the thin wall portion 66 as a low-rigidity portion, and the dynamic spring constant can be effectively reduced. .

  Further, since the boundary line portion 64 is formed thinner than the thin wall portion 66 by the circumferentially extending concave grooves 70 provided on both the front and back surfaces of the elastic wall 46, it is a partition against high frequency fine amplitude vibration. The plates 48 and 50 can be further reciprocated in the axial direction X, and the dynamic spring constant can be further effectively reduced. The concave groove 70 may be provided on only one of the front and back wall surfaces of the elastic wall 46, but it is more preferable to provide the groove 70 on both sides.

  On the other hand, when a large amplitude vibration in the low frequency region occurs, the displacement amount of the pair of partition plates 48 and 50 is regulated by the elastic wall 46, so that the liquid passes through the orifice 42 and the first liquid chamber 18A and the second liquid. The liquid can be circulated between the chambers 18B, and the vibration can be attenuated by the liquid flow effect. In particular, according to the present embodiment, the partition plates 48 and 50 are formed by the thick wall portions 68 on the outer peripheral side that are disposed to face the partition plates 48 and 50 through the gap 74 that gradually increases toward the radially outward Ko side. The reciprocating displacement can be effectively regulated.

  Further, the thick wall portion 68 contacts the partition plates 48 and 50 at the inner peripheral edge, and the gap 74 is formed between the thick wall portion 68 and the partition plates 48 and 50 on the outer peripheral side of the contact portion 76. Therefore, it is possible to prevent the generation of abnormal noise due to the collision between the thick wall portion 68 and the partition plates 48 and 50. Further, during large amplitude vibration, the contact area between the thick wall portion 68 and the partition plates 48 and 50 increases gradually and smoothly from the inner periphery side to the outer periphery side, and the partition plates 48 and 50 are displaced without causing abnormal noise. The regulatory effect can be enhanced. Furthermore, since the contact portion 76 is only the inner peripheral edge of the thick wall portion 68, the reciprocating displacement of the partition plates 48 and 50 by the thin wall portion 66 at the time of high frequency fine amplitude is not hindered.

  In the present embodiment, the raised portion 78 is provided on the outer peripheral portion 46A of the elastic wall 46, and the convex portion 80 is provided on the inner peripheral surface 44A of the orifice forming member 44 to which the outer peripheral portion 46A is bonded and fixed. Further, the rigidity of the outer peripheral portion 46A of the elastic wall 46 can be increased, and the displacement restriction effect of the partition plates 48 and 50 at the time of large amplitude vibration can be further enhanced. Further, since the raised portion 78 provided on the first liquid chamber 36A side is made of rubber, even if the vibration-isolating base 16 is excessively displaced downward and hits the raised portion 78, the vibration-isolating base 16 is damaged. Can be prevented.

  In the present embodiment, the distance between the wall surface 66A of the thin wall portion 66 and the first plate surfaces 48B and 50B of the partition plates 48 and 50 opposed to the wall surface 68A of the thick wall portion 68 and this wall surface 68A. Is set larger than the maximum dimension of the gap 74 between the second plate surfaces 48C and 50C of the partition plates 48 and 50 facing each other. Therefore, the range in which the partition plates 48 and 50 reciprocate is determined only by the gap 74 in the thick wall portion 68 on the outer peripheral side, and the thin wall portion 66 on the inner peripheral side not only has a small amplitude vibration but also has a large amplitude vibration. Also, it does not contact the partition plates 48 and 50. Therefore, it is possible to prevent abnormal noise due to the collision between the thin wall portion 66 and the partition plates 48 and 50 during large amplitude vibration.

  FIGS. 12 to 14 show the movement with respect to vibration in the axial direction X of the liquid-filled vibration isolator 10 according to the above embodiment and the liquid-filled vibration isolator according to the conventional example having the partition shown in Patent Document 2. It is the graph which showed the characteristic. 12 and 13, characteristics with respect to large amplitude vibration (amplitude = ± 1.0 mm) in a low frequency region, and FIG. 14 shows characteristics with respect to fine amplitude vibration (amplitude = ± 0.05 mm) in a high frequency region. Each is shown.

  As shown in FIGS. 12 and 13, in the embodiment, the dynamic spring constant and the damping coefficient at the time of low-frequency large-amplitude vibration are higher than those of the conventional example, and the damping performance against large-amplitude vibration is excellent. . Further, as shown in FIG. 14, in the embodiment, the dynamic spring constant at the time of high-frequency fine amplitude vibration is low and the vibration-proofing effect is excellent as compared with the conventional example.

  As described above, according to the present embodiment, the improvement in the damping performance with respect to the low frequency large amplitude vibration and the reduction of the dynamic spring constant with respect to the high frequency fine amplitude vibration can be achieved at a higher level than ever before.

  In the above embodiment, the concave groove 70 is continuously provided over the entire circumference of the elastic wall 46 in order to increase the effect of reducing the dynamic spring constant in the high frequency range, but is not necessarily continuous over the entire circumference. For example, you may provide intermittently in the circumferential direction. When interrupted, the interrupted portion of the concave groove 70 serves as a bridging portion that connects the thin wall portion 66 on the inner peripheral side of the boundary line portion 64 and the thick wall portion 68 on the outer peripheral side. In doing so, the rubber flow between the thin wall portion 66 and the thick wall portion 68 can be ensured, and the moldability can be improved.

  In the liquid-filled vibration isolator 10 of the present embodiment, since it is fixed to the vehicle body frame 102 by the stopper fixing portion 39 provided on the stopper member 28, the rigidity strength for supporting the weight of the engine 100 is increased. The stopper member 28 can be used, and the rigidity strength required for the intermediate member 26 and the diaphragm member 27 can be reduced. Therefore, the thickness of the intermediate member 26 and the diaphragm member 27 can be reduced and the material can be changed to a low-strength material, so that the material cost can be reduced and the weight can be reduced.

  Further, since the lower side of the liquid-filled vibration isolator 10 is fixed to the vehicle body frame 102 by the stopper member 28, the vehicle body frame 102 of the liquid-filled vibration isolator 10 is configured. The mounting height from the upper surface of the can be reduced. Therefore, it is easy to ensure the rigidity strength of the entire engine support structure as compared with the conventional structure in which the mounting height from the body frame 102 is high. In addition, the rigidity strength necessary for supporting a load in the horizontal direction can be reduced. Therefore, the stopper member 28 can also be reduced in thickness and changed to a low-strength material, so that the liquid-filled vibration isolator 10 as a whole can be reduced in weight and material cost. .

  In the present embodiment, the lower fixture 14 is assembled integrally using the bent piece 35 provided on the diaphragm member 27. That is, since the stopper member 28, the intermediate member 26, and the diaphragm member 27 are integrally coupled by caulking and fixing with the bent piece 35, the height of the liquid-filled vibration isolator 10 itself is made lower than that of the conventional structure. From this point, it is easy to ensure rigidity and strength.

  In the present embodiment, the stopper member 28 fixed to the vehicle body frame 102 has a thick plate, but the diaphragm member 27 is thinner than this. Therefore, the bending work can be easily performed by forming the bending piece 35 in the diaphragm member 27 and bending the bending piece 35.

  Furthermore, in the present embodiment, the intermediate member side buffer layer 31 and the diaphragm side buffer layer 36 support the partition 22 inside the lower fixture 14 only through a rubber-like elastic material. In combination with the structure of the partition body 22 itself, in which the partition plates 48 and 50 are supported by the elastic wall 46, transmission of abnormal noise from the partition body 22 to the vehicle interior can be further suppressed.

  INDUSTRIAL APPLICABILITY The present invention can be used as various anti-vibration devices for automobiles, such as engine mounts for automobiles, for vibration isolating the vibration generator and the body frame, and can also be used for various vehicles other than automobiles.

Longitudinal sectional view of the liquid filled type vibration isolator according to the embodiment (cross sectional view taken along the line II in FIG. 2) Top view of the vibration isolator Side view of the vibration isolator Longitudinal sectional view of the partition of the vibration isolator The principal part expanded sectional view of the partition Exploded longitudinal sectional view of the partition Top view of the partition Plan view of orifice forming member and elastic wall vulcanization molding constituting the partition Expanded cross-sectional view of the main part during molding of the vulcanized molded body The top view which shows the assembly | attachment state to the vehicle of the vibration isolator A longitudinal sectional view showing a state in which the vibration isolator is assembled to a vehicle Graph showing the relationship between frequency and dynamic spring constant during low-frequency and large-amplitude vibration Graph showing the relationship between frequency and damping coefficient during low-frequency large-amplitude vibration A graph showing the relationship between frequency and dynamic spring constant during high-frequency, small-amplitude vibration

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Liquid enclosure type vibration isolator 12 ... Upper side fixture 14 ... Lower side fixture 16 ... Anti-vibration base | substrate 18 ... Liquid enclosure chamber, 18A ... 1st liquid chamber, 18B ... 2nd liquid chamber 20 ... Diaphragm 22 ... Partition body 23 ... Orifice 26 ... Intermediate member 27 ... Diaphragm member 28 ... Stopper member 29 ... Anti-vibration base connecting portion 30 ... Intermediate overhanging portion 31 ... Intermediate member side buffer layer 32 ... Bottom portion, 32A ... Opening portion 33 ... Cylindrical portion 34 ... Diaphragm-side overhanging portion 35 ... bent piece 36 ... diaphragm-side buffer layer 37 ... stopper regulating portion 38 ... stopper overhanging portion 39 ... stopper fixing portion 44 ... orifice forming member, 44A ... inner peripheral surface, 44D ... first liquid chamber Side end 46 ... elastic wall, 46A ... outer peripheral part 48 ... upper partition plate, 48B ... first plate surface, 48C ... second plate surface 50 ... lower partition plate, 50B ... first plate surface, 50C ... second Plate surface 60 ... connecting part 64 ... boundary Portion 66 ... Thin wall portion 66A ... Wall surface 68 ... Thick wall portion 68A ... Wall surface 70 ... Concave groove 74 ... Gap 76 ... Abutting portion 78 ... Raised portion 78A ... Tip 80 ... Convex portion 80B ... Second liquid Side surface 90 on the chamber side ... Mold C ... Circumferential direction Ko ... Radially outward, Ki ... Radially inward X ... Axle core direction

Claims (10)

An upper fixture that is attached to the vibration generator, a cylindrical lower fixture that is attached to the vehicle body frame, a vibration-proof base made of a rubber-like elastic material that connects the upper fixture and the lower fixture, A diaphragm made of a rubber-like elastic film that is attached to the lower fixture and forms a liquid enclosure chamber with the vibration isolator base, and the liquid enclosure chamber is a first liquid chamber on the vibration isolator base side and the diaphragm. A liquid-filled vibration isolator comprising a partition that partitions the second liquid chamber on the side, and an orifice that allows the first liquid chamber and the second liquid chamber to communicate with each other;
The lower fixture includes an intermediate member to which the anti-vibration base is attached, and the liquid attached between the anti-vibration base and the diaphragm by being attached to the lower side of the intermediate member to which the diaphragm is attached. A diaphragm member that forms a sealing chamber, and a stopper member that is coupled to the upper side of the intermediate member and exerts a stopper action between the upper fixture,
The stopper member includes a cylindrical stopper regulating portion that surrounds the upper fixture and regulates displacement of the upper fixture, and a stopper fixing portion that projects radially outward from a lower end of the stopper regulating portion, The stopper fixing portion is fixed to the vehicle body frame, so that at least the diaphragm member is embedded in the vehicle body frame.
The partition body is provided on the inner side of the lower fixture to form an annular orifice forming member, and an elastic wall made of a rubber-like elastic material that blocks between the inner peripheral surfaces of the orifice forming member, A pair of partition plates that are connected to each other via a connecting portion that penetrates the radial center of the elastic wall, and sandwiches the elastic wall in the axial direction of the elastic wall;
The elastic wall includes a boundary line portion extending in a circumferential direction, a thin wall portion having a wall surface spaced from and opposed to a plate surface of the partition plate on an inner peripheral side of the boundary line portion, and the boundary line On the outer peripheral side of the part, it is thickened in a stepped manner with respect to the thin wall part with the boundary line part as a boundary, and gradually widens radially outward from the plate surface of the partition plate A thick wall portion having a wall surface that forms a gap,
A liquid-filled vibration isolator characterized by that.   The liquid-filled vibration isolator according to claim 1, wherein the boundary line portion is formed thinner than the thin wall portion by a circumferentially extending concave groove provided on at least one wall surface of the elastic wall. .   The distance between the wall surface of the thin wall portion and the plate surface of the partition plate facing the wall surface is greater than the maximum dimension of the gap between the wall surface of the thick wall portion and the plate surface of the partition plate facing the wall surface. The liquid-filled vibration isolator according to claim 1 or 2, wherein the liquid-filled vibration isolator is set to be larger.   The thick wall portion contacts the plate surface of the partition plate at the inner peripheral edge, and the wall surface of the thick wall portion is radially outward from the outer peripheral side of the contact portion with the plate surface of the partition plate. The liquid-filled vibration isolator according to any one of claims 1 to 3, wherein the gap gradually increases toward the side.   The wall surface of the thick wall portion and the plate surface of the partition plate facing the wall surface are each formed in an inclined surface shape that is located on the outer side in the axial direction of the elastic wall toward the radially outer side. The liquid-filled vibration isolator according to claim 1, wherein the thin wall portion is formed to have a constant thickness in a radial direction.   On the outer peripheral portion of the elastic wall that is bonded and fixed to the inner peripheral surface of the orifice forming member, the elastic wall protrudes outward in the axial direction with respect to the inclined wall surface of the thick wall portion. The liquid-filled type vibration damping device according to claim 5, further comprising a raised portion that increases the rigidity of the outer peripheral portion.   The convex part which protrudes radially inward and raises the rigidity of the outer peripheral part of the elastic wall is provided on the inner peripheral surface of the orifice forming member to which the outer peripheral part of the elastic wall is bonded and fixed. Liquid-filled vibration isolator. The outer peripheral portion of the elastic wall, which is bonded and fixed to the inner peripheral surface of the orifice forming member, has a wall surface on the first liquid chamber side of the elastic wall with respect to the inclined wall surface of the thick wall portion. A raised portion is provided on the first liquid chamber side, and the tip of the raised portion is located closer to the first liquid chamber side than the first liquid chamber side end of the orifice forming member;
On the inner peripheral surface of the orifice forming member to which the outer peripheral portion of the elastic wall is bonded and fixed, a convex portion protruding radially inward is provided at the base portion on the second liquid chamber side of the elastic wall, The side surface of the convex portion on the second liquid chamber side is formed on a straight surface perpendicular to the axial direction of the elastic wall, and the side surface of the convex portion on the second liquid chamber side is formed when the elastic wall is formed. The liquid-filled vibration isolator according to claim 5, which is a pressing surface in the axial direction against the mold. The intermediate member includes an anti-vibration base connecting portion to which the anti-vibration base is connected, and an intermediate overhanging portion protruding in a flange shape radially outward from the anti-vibration base connecting portion,
The diaphragm member includes a bottom portion having an opening blocked by the diaphragm, a cylindrical portion standing from an outer edge of the bottom portion, and a flange-like shape protruding radially outward from an upper end of the cylindrical portion. A diaphragm side overhanging portion overlaid on the lower surface of the intermediate overhanging portion, and a pair of bent pieces standing from the outer edge of the diaphragm side overhanging portion and sandwiching the tubular portion,
The stopper member includes a stopper-side protruding portion that protrudes radially outward from a lower end of the stopper restricting portion and overlaps an upper surface of the intermediate protruding portion, and the stopper fixing portion is provided on the stopper side. It is provided in a pair that protrudes radially outward from the outer edge of the overhang part and is positioned with the stopper restricting part in between,
The stopper member is formed by sandwiching the intermediate overhanging portion between the diaphragm side overhanging portion and the stopper side overhanging portion and folding back the bent piece of the diaphragm member to the upper surface of the stopper side overhanging portion. The liquid-filled vibration isolator according to claim 1, wherein the intermediate member and the diaphragm member are combined. On the upper surface of the bottom portion of the diaphragm member and the inner peripheral surface of the cylindrical portion, a diaphragm side buffer layer made of a rubber-like elastic material connected to the diaphragm is covered,
An intermediate member-side buffer layer made of a rubber-like elastic material connected to the vibration isolation base is covered at the lower end of the vibration isolation base connecting portion of the intermediate member,
The orifice forming member of the partition body is fitted to an inner peripheral surface of the diaphragm side buffer layer covering the tubular portion, and the intermediate member side buffer layer and the diaphragm side buffer layer covering the bottom portion The liquid-filled vibration isolator according to claim 9, wherein the partition body is supported inside only the rubber-like elastic material by being sandwiched between them.

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