Fluid-filled vibration isolation device

Abstract

This invention provides a novel fluid-sealed vibration damping device that can suppress the influence of hydraulic pressure absorption on a rubber elastic plate and tune the switching characteristics of the opening and closing of the communication port. In this fluid-sealed vibration damping device, the communication port connecting the pressure chamber and the balance chamber is covered by a rubber elastic plate, and the device absorbs minor pressure fluctuations based on the elastic deformation of the rubber elastic plate. A peripheral abutment holding portion, which overlaps with a partition member, is partially provided circumferentially on the rubber elastic plate. An elastic deformation region is provided circumferentially between the peripheral abutment holding portions in the rubber elastic plate. This elastic deformation region separates from the partition member, thereby allowing fluid flow from the balance chamber to the pressure chamber through the communication port. Radial reinforcing ribs are formed protruding from the rubber elastic plate, extending outwards from the inner peripheral abutment holding portion, which overlaps with the partition member, toward the elastic deformation region.

Description

Technical Field

[0001] This invention relates to a fluid-sealed vibration damping device for engine mounts and the like in motor vehicles. Background Technology

[0002] Currently, fluid-sealed vibration damping devices for motor vehicle engine mounts and the like are known. For example, as shown in Japanese Patent Application Publication No. 2016-125632 (Patent Document 1), the fluid-sealed vibration damping device has a pressure chamber and a balance chamber that enclose an incompressible fluid, and exerts a vibration damping effect based on the flow of the enclosed fluid.

[0003] Furthermore, in Patent Document 1, a communication port is provided on the separating member that separates the pressure chamber and the balance chamber, allowing the pressure chamber and the balance chamber to communicate with each other, and a rubber elastic plate is provided to cover the communication port in a closed state. The rubber elastic plate elastically deforms based on the relative pressure change between the pressure chamber and the balance chamber, thereby releasing the closed state of the communication port and allowing communication through the communication port between the pressure chamber and the balance chamber.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2016-125632 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] In the construction of Patent Document 1, in order to effectively exert the vibration damping performance, it is necessary to control the magnitude of the relative pressure difference between the pressure chamber and the equilibrium chamber, the presence / degree of deformation of the rubber elastic plate, etc. Such control of the deformation of the rubber elastic plate can be achieved, for example, by adjusting the deformation stiffness of the rubber elastic plate.

[0009] However, it is known that the rubber elastic plate in Patent Document 1 not only facilitates the opening and closing of the connection port, but its own deformation-induced absorption function of absorbing small pressure changes (hydraulic absorption function) also contributes to vibration damping performance. Therefore, sometimes when only the opening and closing of the connection port is considered and the deformation stiffness of the rubber elastic plate is adjusted, the hydraulic absorption function of the rubber elastic plate is reduced, and the desired vibration damping performance cannot be obtained. In other words, when considering the hydraulic absorption function of the rubber elastic plate, there is sometimes a risk that the degree of freedom of stiffness tuning used to control the deformation of the rubber elastic plate will be reduced, and it is difficult to match the switching characteristics of the opening and closing of the connection port with the required performance.

[0010] The present invention addresses the problem of providing a novel fluid-sealed vibration damping device that can suppress the influence of the absorption function of small pressure fluctuations caused by the deformation of the rubber elastic plate, and can control the deformation of the rubber elastic plate with a large degree of freedom.

[0011] means for solving problems

[0012] Hereinafter, preferred embodiments for mastering the present invention will be described. However, the embodiments described below are illustrative and can be used not only in appropriate combinations but also independently identified and used as much as possible, and can be used in appropriate combinations with any constituent element described in other embodiments. Therefore, in the present invention, various other embodiments can be implemented without being limited to the embodiments described below.

[0013] The first method is a fluid-sealed vibration damping device, which includes a pressure chamber and a balance chamber. The pressure chamber and balance chamber are sealed with an incompressible fluid. A communication port connecting the pressure chamber and balance chamber is formed on a separating member. A rubber elastic plate is arranged to cover the communication port from the pressure chamber side. Based on the elastic deformation of the rubber elastic plate caused by the pressure difference between the pressure chamber and the balance chamber applied to each side of the rubber elastic plate, it performs a function of absorbing small pressure fluctuations. In the fluid-sealed vibration damping device, the outer surface of the rubber elastic plate... The periphery is partially provided with an outer peripheral abutment holding portion that is held to overlap with the partition member, and an elastic deformation region is provided between the outer peripheral abutment holding portions in the rubber elastic plate in the circumferential direction. The elastic deformation region is separated from the partition member based on the pressure difference between the pressure chamber and the balance chamber, thereby allowing fluid to flow from the balance chamber to the pressure chamber through the communication port. Radial reinforcing ribs are formed protruding on at least one surface of the rubber elastic plate. The radial reinforcing ribs extend outward from the inner peripheral abutment holding portion held to overlap with the partition member toward the elastic deformation region.

[0014] According to the fluid-sealed vibration damping device constructed in accordance with this method, radial reinforcing ribs are provided in the elastic deformation region where the open connection allows fluid flow. The deformation rigidity of the elastic deformation region can be adjusted by the radial reinforcing ribs, thereby preventing unnecessary opening of the connection and avoiding the generation of impact noise caused by excessive deformation of the elastic deformation region.

[0015] In particular, the radial reinforcing ribs extend from the inner periphery of the rubber elastic plate to the outer periphery towards the elastic deformation region, as detailed in the embodiment. Thus, the radial reinforcing ribs effectively affect the deformation stiffness in the thickness direction of the elastic deformation region and suppress the influence of the radial reinforcing ribs on the absorption function of small pressure changes based on the elastic deformation of the rubber elastic plate, thereby effectively obtaining the vibration damping performance brought about by the absorption function of small pressure changes.

[0016] The second approach is based on the fluid-sealed vibration damping device described in the first approach, where the outer peripheral ends of the radial reinforcing ribs are located at the circumferential center of each of the elastic deformation regions.

[0017] According to the fluid-sealed vibration damping device constructed in accordance with this method, the influence of radial reinforcing ribs on the deformation stiffness in the thickness direction of the elastic deformation region is balanced in the circumferential direction. For example, it is possible to prevent the deformation mode of the elastic deformation region from being distorted due to the influence of the radial reinforcing ribs.

[0018] The third approach is to provide a radial reinforcing rib in one of the elastic deformation regions, based on the fluid-sealed vibration damping device described in the first or second approach.

[0019] According to the fluid-sealed vibration damping device constructed in accordance with this method, compared with the case of setting multiple radial reinforcing ribs, the range of the influence of the deformation stiffness caused by the radial reinforcing ribs in the circumferential direction can be limited, thereby easily suppressing the influence on the absorption function of small pressure changes.

[0020] The fourth method is based on the fluid-sealed vibration damping device described in any of the first to third methods, wherein the radial reinforcing ribs protrude from the surface of the rubber elastic plate on the side of the balance chamber.

[0021] According to the fluid-sealed vibration damping device constructed in accordance with this method, by setting the radial reinforcing ribs to protrude towards the balance chamber side, the radial reinforcing ribs easily contribute to the rigidity during deformation of the pressure chamber side when the communication port is opened to the elastic deformation region. Therefore, the radial reinforcing ribs can be effectively influenced relative to the opening and closing switching characteristics of the communication port.

[0022] The fifth method is based on the fluid-sealed vibration damping device described in the fourth method, wherein a circumferentially extending annular cushioning protrusion is provided on the surface of the balance chamber side in the rubber elastic plate, and the protrusion height dimension of the radial reinforcing rib is smaller than the protrusion height dimension of the annular cushioning protrusion.

[0023] According to the fluid-sealed vibration damping device constructed in accordance with this method, for example, when the rubber elastic plate is struck from a state away from the pressure chamber side relative to the partition member due to deformation in the thickness direction, the annular buffer protruding on the surface of the rubber elastic plate on the balance chamber side preferentially abuts against the partition member, thereby reducing the initial contact area between the rubber elastic plate and the partition member, thus reducing the impact noise. In particular, since the protrusion height dimension of the annular buffer protrusion is larger than the protrusion height dimension of the radial reinforcing ribs, and the annular buffer protrusion preferentially abuts against the partition member, the reduction of impact noise due to the buffering effect of the annular buffer protrusion is achieved.

[0024] The sixth method is based on the fluid-sealed vibration damping device described in any of the first to fifth methods, wherein the radial reinforcing ribs extend in a generally radial straight line toward the rubber elastic plate.

[0025] According to the fluid-sealed vibration damping device constructed in accordance with this method, radially extending reinforcing ribs, which extend in a generally radially straight line towards the elastic deformation region of the rubber elastic plate, effectively influence the deformation stiffness of the elastic deformation region relative to the radial flexural (bending) deformation of the elastic deformation region located at the outer peripheral end of the rubber elastic plate. Therefore, by using fewer or smaller radially reinforcing ribs, it is possible to suppress the influence of the rubber elastic plate on the absorption function of small pressure variations and effectively tune the deformation characteristics of the elastic deformation region.

[0026] The seventh method is based on the fluid-sealed vibration damping device described in any of the first to sixth methods, with a protrusion protruding toward the pressure chamber side provided in the elastic deformation region. The pressure chamber side of the protrusion is covered by a displacement limiting part provided in the partition member, and the radial reinforcing ribs are provided at the position corresponding to the protrusion in the circumferential direction of the rubber elastic plate.

[0027] According to the fluid-sealed vibration damping device constructed in accordance with this method, the protrusion abuts against the displacement limiting part of the partition member, thereby limiting the amount of deformation of the elastic deformation region towards the pressure chamber side. As a result, the maximum opening area of ​​the communication port is defined by the abutment between the protrusion and the displacement limiting part of the partition member, thereby making it easier to adjust the influence of fluid flow through the communication port on the vibration damping characteristics, etc.

[0028] For example, considering the case that the elastic deformation region is prone to active deformation in the part where the protrusion is formed, radial reinforcing ribs are provided at the position corresponding to the protrusion in the circumferential direction. This can prevent excessive deformation of the elastic deformation region caused by the formation of the protrusion by the radial reinforcing ribs, and thus the deformation mode of the elastic deformation region can be tuned by the radial reinforcing ribs.

[0029] The eighth method is based on the fluid-sealed vibration damping device described in the seventh method, wherein the protruding front end face of the protrusion is formed into a surface shape corresponding to the displacement limiting part, and a radially extending cushioning protrusion is provided on the protruding front end face of the protrusion along the radial direction of the rubber elastic plate.

[0030] In the fluid-sealed vibration damping device constructed according to this method, the contact surfaces between the protrusion and the displacement limiting part of the partition member are formed in approximately corresponding shapes, thereby making it easy for the protrusion to be stably held in contact with the displacement limiting part. Therefore, through the contact between the protrusion and the displacement limiting part, the elastic deformation region is stably maintained in a state that allows fluid flow through the communication port while deforming towards the pressure chamber side.

[0031] Furthermore, radially spaced cushioning protrusions are provided on the protruding front end face of the protrusion, thereby reducing the impact noise when the protrusion abuts against the displacement limiting portion of the separating member through the buffering effect of the radially spaced cushioning protrusions. In particular, for example, when the elastic deformation region provided at the outer peripheral end of the rubber elastic plate deforms into radial flexing, the radially spaced cushioning protrusions extending approximately radially along the rubber elastic plate stably abut against the displacement limiting portion, thus stably exerting the effect of reducing the impact noise caused by the radially spaced cushioning protrusions.

[0032] The ninth method is based on the fluid-sealed vibration damping device described in the seventh or eighth method, wherein a deformation-limiting protrusion is provided on the inner circumferential side of the protrusion in the rubber elastic plate, arranged radially parallel to the protrusion, and the radial reinforcing rib extends continuously radially across these protrusions and deformation-limiting protrusions, and extends further into the inner circumference than the deformation-limiting protrusion.

[0033] According to the fluid-sealed vibration damping device constructed in accordance with this method, when the elastic deformation region deforms towards the pressure chamber side, the deformation limiting protrusion and the protrusion abut against the displacement limiting part of the partition member in stages, thereby achieving the reduction of impact noise.

[0034] Furthermore, the radial reinforcing ribs extend continuously from the inner peripheral retaining portion across the deformation limiting protrusion to the protrusion in a radial direction. Thus, even in the portion where the protrusion and deformation limiting protrusion are formed, if the amount of deformation in the thickness direction of the elastic deformation region increases, the deformation characteristics of the elastic deformation region can be tuned by adjusting the deformation rigidity of the elastic deformation region caused by the radial reinforcing ribs.

[0035] Invention Effects

[0036] According to the present invention, the influence of the rubber elastic plate on the absorption function of small pressure changes caused by deformation can be suppressed, and the deformation of the rubber elastic plate can be controlled with a large degree of freedom. Attached Figure Description

[0037] Figure 1 This is a cross-sectional view showing the engine bracket as a first embodiment of the present invention, which is equivalent to... Figure 3 The diagram of section II.

[0038] Figure 2 yes Figure 1 The sectional view of the engine mount shown is equivalent to Figure 3 The diagram of section II-II.

[0039] Figure 3 yes Figure 1 The top view of the engine mount shown.

[0040] Figure 4 It constitutes Figure 1 A top view of the partition components of the engine mount shown.

[0041] Figure 5 It constitutes Figure 1 A perspective view of the main body of the partition component of the engine mount shown.

[0042] Figure 6 It constitutes Figure 1 A three-dimensional view of the movable membrane of the engine mount shown.

[0043] Figure 7 It is expressed from another perspective Figure 6 The diagram shows a three-dimensional view of the active membrane.

[0044] Figure 8 yes Figure 6 The top view of the active membrane shown.

[0045] Figure 9 yes Figure 6 The image shows a bottom view of the active membrane.

[0046] Figure 10 It is Figure 6 The movable membrane shown is installed at Figure 5 A three-dimensional view of the state of the main body of the partition component.

[0047] Figure 11 yes Figure 10 The diagram shows a top view of the movable membrane installed on the main body of the partition component.

[0048] Figure 12 This is an explanation Figure 1 A diagram showing the deformation of the movable membrane in the engine mount.

[0049] Figure 13 This is a top view of the movable membrane constituting the engine bracket as a second embodiment of the present invention.

[0050] Explanation of reference numerals in the attached figures

[0051] 10: Engine mount (fluid-sealed vibration damping device, first embodiment);

[0052] 12: First installation component;

[0053] 14: Second mounting component;

[0054] 16: Main body rubber elastomer;

[0055] 18: Mounting holes;

[0056] 20: Fixed installation components;

[0057] 22: Supporting components;

[0058] 24: Conical bearing surface;

[0059] 26: Positioning section;

[0060] 28: Support section;

[0061] 30: Recessed area;

[0062] 32: Sealing rubber layer;

[0063] 34: Covered with rubber;

[0064] 36: Flexible membrane;

[0065] 38: Positioning protrusion;

[0066] 40: Separating components;

[0067] 42: Main body of the partition component;

[0068] 44: Cover component (displacement limiting part);

[0069] 46: To accommodate a recessed area;

[0070] 48: Support pin;

[0071] 50: Annular recess;

[0072] 52 (52a, 52b): Lower through hole (connecting port);

[0073] 54: Zhou Cao;

[0074] 56: Conical part;

[0075] 58: Lower connecting hole;

[0076] 60: Hollowed-out recessed area;

[0077] 62: upper through hole;

[0078] 64: Upper connecting hole;

[0079] 66: Movable membrane (rubber elastic plate);

[0080] 68: Through hole;

[0081] 70: Inner perimeter contact and retention part;

[0082] 72: Peripheral contact and retention part;

[0083] 74: Strengthen the connection part;

[0084] 76: Overflow section (elastic deformation area);

[0085] 78: Hydraulic absorption section;

[0086] 80: Protrusion;

[0087] 82: Radial cushioning occurs;

[0088] 84: Deformation-restricting protrusion;

[0089] 86: Circular buffer formation occurs;

[0090] 88: Radial reinforcing ribs;

[0091] 90: Pressure chamber;

[0092] 92: Balance chamber;

[0093] 94: Orifice passage;

[0094] 100: Movable membrane (rubber elastic plate, second embodiment);

[0095] 102: Radial reinforcing ribs. Detailed Implementation

[0096] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0097] Figures 1-3 An engine mount 10 for a motor vehicle is shown as a first embodiment of a fluid-sealed vibration damping device configured according to the invention. The engine mount 10 has a configuration in which a first mounting member 12 and a second mounting member 14 are connected to each other via a main rubber elastomer 16. In the following description, the vertical direction generally refers to the primary vibration input direction, i.e. Figure 1 The up and down direction and the front and back direction refer to Figure 3 The up and down directions and the left and right directions refer to... Figure 1 The left and right directions within. Additionally, in principle, the circumferential direction refers to the direction around the central axis of the support (…). Figure 2 The circumference of the single-dot dashed line in the middle.

[0098] More specifically, the first mounting member 12 is formed as a generally rectangular cylinder with mounting holes 18 opening to the side (front-rear direction), for example, capable of stamping a metal blank.

[0099] The second mounting member 14 consists of a fixed mounting member 20 fixedly mounted to the main rubber elastomer 16 and a support member 22 extending downward from the fixed mounting member 20. The fixed mounting member 20 is formed as a large-diameter ring extending circumferentially with a generally quadrilateral cross-section, and has a tapered bearing surface 24 with its inner circumferential surface facing upward, forming a large diameter. The support member 22 is formed as a cylindrical shape with a downwardly decreasing diameter, and has a positioning part 26 at its upper end that overlaps with the lower surface and outer circumferential surface of the fixed mounting member 20, and an inner flange-shaped support part 28 at its lower end that faces the lower surface of the fixed mounting member 20 in the vertical direction. The fixed mounting member 20 is inserted into the positioning part 26 of the support member 22, thereby positioning the fixed mounting member 20 and the support member 22 to form the second mounting member 14. It should be noted that the fixed mounting member 20 and the support member 22 can be connected to each other. Specifically, for example, the fixed mounting member 20 can be fitted into the positioning part 26, and the fixed mounting member 20 and the support member 22 can be connected to each other. The fixed mounting member 20 and the support member 22 can also be connected to each other by clamping them in the vertical direction on the outer bracket (described later, not shown).

[0100] Furthermore, the first mounting member 12 is disposed above the second mounting member 14, spaced apart, and these first mounting members 12 and second mounting members 14 are elastically connected to each other via a main rubber elastomer 16. The main rubber elastomer 16 is formed in a thick, large-diameter, approximately frustum-shaped cone, with its small-diameter end vulcanized and bonded to the first mounting member 12, and its large-diameter end vulcanized and bonded to the inner circumferential portion of the fixing mounting member 20 of the second mounting member 14, which has a conical bearing surface 24. Thus, the main rubber elastomer 16 is formed as an integrally vulcanized molded article comprising the first mounting member 12 and the fixing mounting member 20.

[0101] A recess 30 is formed on the main rubber elastomer 16. The recess 30 is shaped like an inverted mortar and opens toward the large-diameter end face of the main rubber elastomer 16. Thus, the main rubber elastomer 16 is formed in a longitudinal section with an inclined shape that extends downward between the first mounting member 12 and the fixed mounting member 20. On the outer periphery of the recess 30, a sealing rubber layer 32 integrally formed with the main rubber elastomer 16 is fixedly mounted to the lower surface of the fixed mounting member 20 of the second mounting member 14.

[0102] A cover rubber 34 is fixedly mounted on the first mounting member 12. The cover rubber 34 is fixedly mounted on the inner and outer peripheral surfaces and the front and rear end surfaces of the first mounting member 12, and is integrally formed with the main rubber elastomer 16. The fixed mounting portions of the cover rubber 34 on the upper outer surface and the left and right outer surfaces of the first mounting member 12 are thick and protrude outwards, and through these portions, a buffer rubber for limiting the relative displacement between the first mounting member 12 and the second mounting member 14 is formed.

[0103] A flexible membrane 36 is mounted on an integrally vulcanized molded body of the main rubber elastomer 16. The flexible membrane 36 is formed in the shape of a thin, large-diameter, approximately circular plate and is flexible enough to easily undergo flexural deformation. The flexible membrane 36 is formed such that the outer peripheral portion is thinner than the inner peripheral portion, thereby making it easier to undergo flexural deformation. An annular positioning protrusion 38 protruding upward is integrally formed on the outer peripheral end of the flexible membrane 36. The upper surface of the outer peripheral end overlaps with the lower surface of the fixed mounting member 20 via the separating member 40 described later, and the lower surface of the outer peripheral end overlaps with the upper surface of the support portion 28 of the support member 22. The outer peripheral end is clamped in the vertical direction by the second mounting member 14, thereby supporting the flexible membrane 36.

[0104] A [material] is disposed between the integrally vulcanized molded body rubber elastomer 16 and the flexible membrane 36. Figure 4 The partition member 40 is shown as shown. The partition member 40 is composed of a partition member body 42 and a cover member 44.

[0105] like Figure 5 As shown, the main body 42 of the partition member is generally formed into a roughly circular plate shape. The main body 42 of the partition member is formed into a rigid member made of metal such as aluminum alloy and synthetic resin.

[0106] A generally circular receiving recess 46 with an upward opening is formed on the inner periphery of the main body 42 of the separating member. A generally cylindrical support pin 48 protruding upward is integrally formed on the central part of the bottom wall of the receiving recess 46. An annular recess 50 with an opening to the upper surface of the bottom wall of the receiving recess 46 is provided on the outer periphery of the support pin 48, and the depth dimension of the receiving recess 46 is increased in the annular recess 50. A plurality of lower through holes 52 serving as communication openings are formed through the bottom wall of the annular recess 50 in the vertical direction. In this embodiment, the lower through holes 52 are composed of a plurality of lower through holes 52a arranged circumferentially side by side at the outer periphery of the annular recess 50, and a plurality of lower through holes 52b arranged circumferentially side by side on the inner periphery of the lower through holes 52a. The shapes of these lower through holes 52a and lower through holes 52b are different from each other. However, the shape and size of the plurality of lower through holes 52 can also be approximately the same, and the number and arrangement are not particularly limited.

[0107] A circumferential groove 54 is formed on the outer periphery of the main body 42 of the partition member, which opens to the upper surface and extends circumferentially. The circumferential groove 54 extends circumferentially with a length of less than one circumference, and a tapered portion 56 is provided at one end in the circumferential direction, and a lower connecting hole 58 penetrating the bottom wall is formed at the other end in the circumferential direction.

[0108] like Figure 1 , Figure 2 As shown, a generally circular hollow recess 60 with a downward-facing opening is formed on the inner circumference of the main body 42 of the separating member. The hollow recess 60 has a larger diameter than the receiving recess 46 and is positioned further to the inner circumference than the circumferential groove 54. The lower through hole 52 is configured to connect the receiving recess 46 and the hollow recess 60 axially.

[0109] The cover member 44 is made of metal or the like and is formed into a thin, approximately circular plate shape compared to the main body 42 of the separating member. The cover member 44 is formed into approximately flat surfaces that extend vertically along the axis on both its upper and lower sides. Figure 4 As shown, a plurality of upper through holes 62 extending vertically are formed on the inner periphery of the cover member 44. In this embodiment, the upper through holes 62 are formed in a different shape, size, number, and arrangement than the lower through holes 52 of the partition member body 42, but they may also be formed in a shape, size, number, and arrangement substantially the same as the lower through holes 52. Upper connecting holes 64 extending vertically are formed on the outer periphery of the cover member 44.

[0110] like Figure 1 , Figure 2 As shown, the cover member 44 overlaps and is fixed to the upper surface of the partition member body 42. The method of fixing the cover member 44 to the partition member body 42 is not particularly limited; for example, it can be fixed by means of bonding or welding. Alternatively, for example, a fixing pin protruding upwards can be provided on the partition member body 42, and a fixing hole corresponding to the fixing pin can be provided on the cover member 44. This allows the cover member 44 and the partition member body 42 to be fixed even if the front end of the fixing pin passing through the fixing hole is crushed or melted to expand its diameter.

[0111] With the partition member body 42 and the cover member 44 fixed in place, the opening of the receiving recess 46 of the partition member body 42 is blocked by the cover member 44. The upper through hole 62 of the cover member 44 is provided in the part covering the opening of the receiving recess 46, and the receiving recess 46 is open upward through the upper through hole 62.

[0112] The opening of the peripheral groove 54 of the partition member body 42 is formed as a tunnel-like passage that is covered and blocked by the cover member 44 and extends circumferentially for less than one circumference. One end of the tunnel-like passage opens upward through the upper connecting hole 64 of the cover member 44, and the other end opens downward through the lower connecting hole 58 of the partition member body 42.

[0113] A movable membrane 66, acting as a rubber elastic plate, is disposed in the receiving recess 46 of the main body 42 of the separating member. Figures 6-9 As shown, the movable membrane 66 is generally formed in a roughly circular plate shape. The movable membrane 66 is formed of a rubber elastomer and a resin elastomer, and allows elastic deformation in the thickness direction.

[0114] A circular insertion hole 68 extending through the thickness direction is provided at the radial center of the movable membrane 66. A cylindrical inner circumferential abutment holding portion 70 protruding upwards is provided around the insertion hole 68 in the movable membrane 66. Three outer circumferential abutment holding portions 72, 72, 72 protruding upwards from the outer periphery of the movable membrane 66 and extending circumferentially. The outer circumferential abutment holding portions 72 are positioned on the outer periphery away from the inner circumferential abutment holding portions 70. The three outer circumferential abutment holding portions 72, 72, 72 are equally spaced circumferentially and separated from each other circumferentially. Therefore, the outer circumferential abutment holding portions 72 are partially provided in the circumferential direction. The inner circumferential abutment holding portions 70 and each outer circumferential abutment holding portion 72 are respectively provided with reinforcing connecting portions 74 that extend radially upwards along the movable membrane 66. The reinforcing connecting portion 74 is connected approximately at the center of the outer peripheral abutting retaining portion 72 in the circumferential direction, and the outer peripheral abutting retaining portion 72 extends from the reinforcing connecting portion 74 to both sides in the circumferential direction. Compared with the inner peripheral abutting retaining portion 70 and the outer peripheral abutting retaining portion 72, the upward protrusion height of the reinforcing connecting portion 74 is lower.

[0115] An overflow portion 76, serving as an elastic deformation region, is provided between adjacent outer peripheral abutment and retaining portions 72, 72 in the circumferential direction. The overflow portion 76 is thinner than the outer peripheral abutment and retaining portions 72, making it prone to deformation in the thickness direction. In addition, a hydraulic absorption portion 78 is provided between adjacent reinforcing connecting portions 74 in the circumferential direction, and the hydraulic absorption portion 78 is formed to have approximately the same thickness dimension as the overflow portion 76.

[0116] A protrusion 80 is provided in the circumferential central portion of the overflow portion 76. The protrusion 80 protrudes upward in the overflow portion 76 and has a generally flat upper surface that extends in a generally axially perpendicular direction. In this embodiment, the protrusion 80 is formed in a cuboid shape. The protrusion 80 is disposed circumferentially spaced from the outer peripheral abutment holding portions 72, 72 on both sides of the overflow portion 76. The overflow portion 76 is thick in the circumferential central portion and thin in the circumferential sides due to the presence of the protrusion 80. The protrusion 80 is supported by the thin portion of the overflow portion 76 and the hydraulic absorption portion 78, and the thick protrusion 80 can be displaced in the vertical direction by the deformation of the thin overflow portion 76 and the hydraulic absorption portion 78. In the circumferential central portion of the overflow portion 76 where the protrusion 80 is provided, the movable membrane 66 is formed with a diameter smaller than that of the circumferential end portions of the overflow portion 76 adjacent to the outer peripheral abutment holding portions 72. The inner circumferential end of the protrusion 80 is located further inward than the inner circumferential end of the outer circumferential abutment retainer 72, and the radial dimension of the protrusion 80 is larger than the radial dimension of the circumferential end of the outer circumferential abutment retainer 72. The upward protrusion height of the protrusion 80 is lower than that of both the inner circumferential abutment retainer 70 and the outer circumferential abutment retainer 72. The maximum opening area of ​​the overflow passage in the overflow section 76 is set according to the distance (gap) between the upper surface of the protrusion 80 and the lower surface of the cover member 44.

[0117] Radial buffer protrusions 82 are provided on the upper surface of the protrusion 80. For example... Figure 6 , Figure 8 As shown, the radially arranged cushioning protrusions 82 are continuous and extend linearly in the radial direction. The protrusion height of the radially arranged cushioning protrusions 82 is smaller than that of the protrusion 80, for example, it is formed to be less than 1 / 5 of the protrusion height of the protrusion 80. The width of the radially arranged cushioning protrusions 82 in the circumferential direction of the active membrane 66 is smaller than that of the protrusion 80, for example, it is formed to be less than 1 / 3 of the width of the protrusion 80. The radially arranged cushioning protrusions 82 are preferably formed with a tapering shape at the front end, where the width dimension decreases upwards.

[0118] A deformation-limiting protrusion 84 protruding upward is provided on the inner circumferential side of the protrusion 80 in the active membrane 66. The deformation-limiting protrusions 84 are arranged radially side-by-side on the protrusion 80, and are positioned radially away from either the inner circumferential abutment holding portion 70 or the protrusion 80. The deformation-limiting protrusion 84 is provided in the hydraulic absorption portion 78 of the active membrane 66, and is positioned at the circumferential center of the hydraulic absorption portion 78 where the deformation amount is prone to increase. The deformation-limiting protrusion 84 is preferably positioned at the radial center of the hydraulic absorption portion 78 and the overflow portion 76, which allow deformation and / or displacement. In this embodiment, it is positioned radially closer to the protrusion 80 than the inner circumferential abutment holding portion 70. The deformation-limiting protrusion 84 is preferably a front-end tapering shape with at least its front end portion tapering towards the protruding front end. In this embodiment, the base portion is formed in a generally cylindrical shape, and the front end portion is formed in a generally spherical cross-section that tapers upward towards the front end.

[0119] like Figure 7 , Figure 9 As shown, a plurality of circumferentially extending annular buffer protrusions 86 are protruding from the lower surface of the active membrane 66. The annular buffer protrusions 86 extend continuously throughout the circumference and protrude downward. The annular buffer protrusions 86 have a front-tapered cross-section with a width dimension decreasing towards the protruding front end, and in this embodiment, they have a generally hemispherical cross-section. The plurality of annular buffer protrusions 86 with different diameters are arranged concentrically, and in this embodiment, four annular buffer protrusions 86, 86, 86, 86 are arranged at radially separated positions. The annular buffer protrusions 86 are arranged further outward than the inner circumferential abutment holding portion 70. The outermost annular buffer protrusion 86 is located on the lower surface of the overflow portion 76, and the other annular buffer protrusions 86 are located on the lower surface of the hydraulic absorption portion 78. For example, the protrusion height dimension of the annular buffer protrusions 86 is formed to be less than 1 / 5 of the thickness dimension of the inner circumferential end of the active membrane 66 provided in the inner circumferential abutment holding portion 70. The radial width dimension of the annular buffer 86 is smaller than the radial width dimension of the inner circumferential abutment retaining portion 70, for example, it is formed to be less than 1 / 3 of the radial width dimension of the inner circumferential abutment retaining portion 70.

[0120] A plurality of radially extending reinforcing ribs 88 are formed protruding from the lower surface of the active membrane 66. The radially extending reinforcing ribs 88 extend radially in a straight line and protrude downwards. The radially extending reinforcing ribs 88 have a tapering profile with a width decreasing towards the protruding front end, and in this embodiment, extend radially in a generally hemispherical profile. Preferably, the downward protrusion height of the radially extending reinforcing ribs 88 is smaller than that of the annular buffer protrusions 86. Preferably, the width of the radially extending reinforcing ribs 88 is approximately the same as or slightly smaller than that of the annular buffer protrusions 86. The radially extending reinforcing ribs 88 extend outwards from the inner periphery of the retaining portion 70 toward the overflow portion 76, and are positioned further outwards than the innermost annular buffer protrusion 86, thus extending to the outer periphery of the active membrane 66. The radially extending reinforcing ribs 88 intersect with the plurality of annular buffer protrusions 86, and are integrally formed with the annular buffer protrusions 86 at the intersecting portions, extending radially between these plurality of annular buffer protrusions 86.

[0121] Radial reinforcing ribs 88 are disposed on the portion of the movable membrane 66 corresponding to the overflow portion 76 in the circumferential direction, and in this embodiment, they are located at the circumferential center of the overflow portion 76. In this embodiment, one radial reinforcing rib 88 is provided relative to one overflow portion 76, and three radial reinforcing ribs 88, 88, 88 are provided. The three radial reinforcing ribs 88, 88, 88 are arranged to be approximately equal in the circumferential direction. The radial reinforcing ribs 88 are located approximately at the center in the circumferential direction of the movable membrane 66, corresponding to the protrusion 80 and the deformation limiting protrusion 84 that are provided on the upper surface of the overflow portion 76. The radial reinforcing ribs 88 extend radially across the protrusion 80 and the deformation limiting protrusion 84, and extend further into the inner circumference than the deformation limiting protrusion 84.

[0122] A movable membrane 66, configured in this manner, is inserted into the receiving recess 46 of the partition member body 42. A support pin 48 of the partition member body 42 is inserted into a through hole 68, and its outer peripheral surface overlaps with the inner peripheral surface of the receiving recess 46, thereby radially positioning the movable membrane 66 against the partition member body 42. Furthermore, corresponding protrusions and concave surfaces are provided on the outer peripheral surface of the movable membrane 66 and the inner peripheral wall of the receiving recess 46, restricting circumferential rotation within the receiving recess 46 and thus circumferentially positioning the movable membrane 66 against the partition member body 42. The movable membrane 66 is positioned in the receiving recess 46 such that it covers the lower through hole 52 from above. It should be noted that the outer diameter of the movable membrane 66 is smaller than the inner diameter of the receiving recess 46, and the outer peripheral surface of the movable membrane 66 is located on the inner periphery relative to the inner peripheral surface of the receiving recess 46.

[0123] The cover member 44 is mounted on the partition member body 42, thereby maintaining the following overlapping state: the inner circumferential abutment holding portion 70 and the outer circumferential abutment holding portion 72 of the movable membrane 66 are axially clamped between the inner surface of the bottom wall of the receiving recess 46 and the cover member 44, and the movable membrane 66 abuts against the bottom wall of the receiving recess 46 at the inner circumferential abutment holding portion 70 and the outer circumferential abutment holding portion 72. The overflow portion 76 and the hydraulic absorption portion 78 of the movable membrane 66 are spaced downward relative to the cover member 44, allowing deformation in the upward thickness direction.

[0124] The upper part of the protrusion 80 of the movable membrane 66 is covered by a cover member 44, which serves as a displacement limiting part. The outer peripheral portion of the protrusion 80 is positioned further outward than the upper through-hole 62, and at least the circumferentially central portion of the radially arranged buffer protrusion 82 is located between the circumferentially adjacent upper through-holes 62, 62, and is almost not exposed from the upper through-holes 62, but is covered by the cover member 44. Furthermore, the upper part of the deformation limiting protrusion 84 of the movable membrane 66 is covered by the cover member 44. The deformation limiting protrusion 84 is located between the circumferentially adjacent upper through-holes 62, 62, and is not exposed from the upper through-holes 62, but is covered by the cover member 44. The lower surface of the cover member 44 is formed as a plane that extends substantially perpendicular to the axis, and extends substantially parallel to the upper surfaces of the protrusion 80 and the deformation limiting protrusion 84, which are respectively formed as planes.

[0125] The partition member 40, which houses the movable membrane 66, is positioned axially between the main rubber elastomer 16 and the flexible membrane 36, with its outer peripheral end mounted on the second mounting member 14. That is, the outer peripheral end of the partition member 40 is inserted between the axially opposing surfaces of the fixed mounting member 20 and the support portion 28 of the support member 22 in the second mounting member 14, and is held by these fixed mounting members 20 and support members 22.

[0126] The sealing rubber layer 32, integrally formed with the main rubber elastomer 16, is clamped between the fixed mounting member 20 and the separating member 40, thereby sealing the overlapping surfaces of the fixed mounting member 20 and the separating member 40 with a liquid seal. Furthermore, the outer peripheral end of the flexible membrane 36 is disposed between the outer peripheral end of the separating member 40 and the support portion 28 of the support member 22, thereby clamping the outer peripheral end of the flexible membrane 36 between the separating member 40 and the support member 22, and sealing the overlapping surfaces of the support portion 28 of the support member 22 and the separating member 40 with a liquid seal.

[0127] Between the main rubber elastomer 16 and the partition member 40, a portion of the wall is formed by the main rubber elastomer 16, forming the pressure chamber 90 that causes internal pressure fluctuations through elastic deformation of the main rubber elastomer 16. Additionally, between the partition member 40 and the flexible membrane 36, a portion of the wall is formed by the flexible membrane 36, forming a balance chamber 92 with substantially constant internal pressure through volume changes caused by deformation of the flexible membrane 36. The pressure chamber 90 and the balance chamber 92 are sealed with incompressible liquids such as water, ethylene glycol, alkylene glycol, polyalkylene glycol, silicone oil, or mixtures thereof. The sealing fluid for the pressure chamber 90 and the balance chamber 92 is preferably a low-viscosity fluid with a viscosity of 0.1 Pa·s or less.

[0128] The pressure chamber 90 and the balance chamber 92 are interconnected via a throttle passage 94. The throttle passage 94 consists of a circumferential groove 54, an upper connecting hole 64, and a lower connecting hole 58. One end of the throttle passage opens into the pressure chamber 90, and the other end opens into the balance chamber 92. By taking into account the wall spring stiffness of the pressure chamber 90 and adjusting the ratio of the passage's cross-sectional area to its length, the tuning frequency of the throttle passage 94, i.e., the resonant frequency of the flowing fluid, is tuned to the frequency of the vibration of the object being isolated. For example, the throttle passage 94 is tuned to a low frequency equivalent to a few Hz, similar to engine vibration.

[0129] The receiving recess 46 of the partition member 40 is connected to the pressure chamber 90 through the upper through-hole 62 of the cover member 44, and to the balance chamber 92 through the lower through-hole 52 of the partition member body 42. In other words, the pressure chamber 90 and the balance chamber 92 are interconnected through a flow path including the lower through-hole 52. Thus, hydraulic pressure from the pressure chamber 90 is applied to the upper surface of the movable membrane 66 disposed in the receiving recess 46, and hydraulic pressure from the balance chamber 92 is applied to the lower surface of the movable membrane 66. Moreover, when a relative pressure change occurs between the pressure chamber 90 and the balance chamber 92, the hydraulic pressure absorption portion 78 of the movable membrane 66 deforms along the thickness direction based on the pressure change, and substantial fluid flow occurs between the pressure chamber 90 and the balance chamber 92. The deformation of the hydraulic absorption section 78 in the thickness direction actively generates a tuning frequency that is higher than the tuning frequency of the throttle orifice passage 94 under resonant conditions. For example, it is tuned to a medium frequency of tens of Hz, which is equivalent to idling vibration, or to a high frequency of tens of Hz, which is equivalent to driving roar.

[0130] The engine mount 10, configured as described above, has an inner bracket (not shown) inserted into the first mounting member 12, thereby mounting the first mounting member 12 to the power unit side (not shown) via the inner bracket. Additionally, the engine mount 10 has an outer bracket (not shown) fitted onto the outer peripheral surface of the second mounting member 14, thereby mounting the second mounting member 14 to the vehicle body side (not shown) via the outer bracket. Thus, the engine mount 10 is clamped between the power unit side and the vehicle body side, thereby providing vibration-damping connection between the two sides.

[0131] When the engine mount 10 is installed in the vehicle, and a low-frequency, large-amplitude vibration equivalent to engine vibration is input between the first mounting member 12 and the second mounting member 14, the relative pressure change between the pressure chamber 90 and the balance chamber 92 actively generates fluid flow through the throttle orifice passage 94 in a resonant state. This achieves a vibration damping effect (high attenuation effect) based on fluid flow, thereby reducing vibration energy.

[0132] When low-frequency, large-amplitude vibrations are input, the deformation of the hydraulic absorption section 78 of the movable diaphragm 66 in the thickness direction cannot follow the input vibration, and the hydraulic transmission effect caused by the deformation cannot be effectively utilized. Therefore, the internal pressure fluctuation of the pressure chamber 90 is ensured not to decrease due to the hydraulic absorption effect of the movable diaphragm 66, thereby efficiently generating fluid flow through the throttling orifice passage 94 and effectively utilizing the vibration damping effect of the throttling orifice passage 94.

[0133] When a vibration input at a frequency higher than the tuning frequency is applied, the throttle orifice passage 94 becomes substantially blocked due to anti-resonance. Therefore, when a small-amplitude vibration at a medium or high frequency, equivalent to idling vibration or driving roar, is applied between the first mounting member 12 and the second mounting member 14, it plays a role in transferring the internal pressure of the pressure chamber 90 to the balance chamber 92 through the fluid flow through the throttle orifice passage 94.

[0134] Therefore, when small-amplitude vibrations of medium or high frequency are input, the hydraulic absorption section 78 of the active membrane 66 undergoes slight deformation along the thickness direction with the input vibration, thereby generating substantial fluid flow between the pressure chamber 90 and the balance chamber 92, and the internal pressure variation of the pressure chamber 90 is transmitted to the balance chamber 92. This achieves a vibration damping effect based on the absorption of small pressure variations by the active membrane 66 (due to the vibration insulation effect caused by the low-dynamic spring), thereby reducing the transmission of vibration to the vibration-damping component, i.e., the vehicle body side.

[0135] However, sometimes when the internal pressure of the pressure chamber 90 drops sharply and significantly due to the input of a large load, gas phase separation occurs in the pressure chamber 90, and the impact noise when the growing bubbles burst may become a problem as cavitation noise.

[0136] Therefore, the engine mount 10 reduces cavitation noise through the overflow portion 76 provided on the movable diaphragm 66. That is, when the internal pressure of the pressure chamber 90 decreases significantly as cavitation becomes a problem, the overflow portion 76 provided at the outer peripheral end of the movable diaphragm 66 draws negative pressure towards the pressure chamber 90, such as... Figure 12 As shown, the overflow section 76 is separated from the inner surface of the bottom wall of the receiving recess 46 and extends upwards. Thus, the lower through-hole 52 opens into the receiving recess 46, and the pressure chamber 90 and the balance chamber 92 are connected without passing through the moving membrane 66 via the overflow path formed by the lower through-hole 52, the receiving recess 46, and the upper through-hole 62. As a result, fluid flows from the balance chamber 92 into the pressure chamber 90 through the overflow path, and the internal pressure drop in the pressure chamber 90 is rapidly reduced or even eliminated.

[0137] In this embodiment, a protrusion 80 is provided on the overflow portion 76. When the overflow portion 76 is separated from the inner surface of the bottom wall of the receiving recess 46 to form an overflow passage, the protrusion 80 abuts against the cover member 44, which serves as a displacement limiting part. Thus, the amount of upward deformation (displacement) of the overflow portion 76 is determined by the protrusion 80, and the cross-sectional area of ​​the overflow passage in the overflow portion 76 is formed to an appropriate size. Furthermore, the upper surface of the protrusion 80 is formed into a flat shape corresponding to the lower surface of the cover member 44, thereby ensuring stable contact between the upper surface of the protrusion 80 and the lower surface of the cover member 44, and achieving stable positioning and retention of the overflow portion 76.

[0138] A radially arranged buffer protrusion 82 is provided on the upper surface of the protrusion 80. Therefore, when the protrusion 80 abuts against the cover member 44, the radially arranged buffer protrusion 82 preferentially abuts against the cover member 44. As a result, the initial contact area between the protrusion 80 and the cover member 44 is reduced due to the radially arranged buffer protrusion 82, thereby reducing the impact noise caused by the buffering effect of the radially arranged buffer protrusion 82. Furthermore, the radially arranged buffer protrusion 82 extends radially, therefore, as... Figure 12 As shown, when the upper surface of the protrusion 80 is inclined vertically in the radial direction to abut against the lower surface of the cover member 44, the radially spaced cushioning protrusions 82 also stably and preferentially abut against the cover member 44. In particular, when the angle of inclination of the cover member 44 relative to the protrusion 80 decreases after the radially spaced cushioning protrusions 82 abut against the cover member 44, the abutment range of the radially spaced cushioning protrusions 82 against the cover member 44 gradually expands in the length direction (radial direction), thus effectively preventing the generation of impact noise caused by the rapid increase in the abutment area.

[0139] The magnitude of the negative pressure in the pressure chamber 90 during operation, when the overflow section 76 is far from the inner surface of the bottom wall of the receiving recess 46 and the lower through hole 52 is opened, is mainly based on the deformation rigidity of the portion detached from the protrusion 80 in the overflow section 76 and the deformation rigidity of the hydraulic absorption section 78 located on the inner circumference of the overflow section 76. In particular, it can also be determined based on... Figure 12 As understood, due to the elastic deformation of the approximately central portion of the hydraulic absorption section 78, which deforms due to the hydraulic pressure difference applied to the upper and lower surfaces, lifting upwards, the upward elastic deformation of the approximately central portion of the hydraulic absorption section 78 is transmitted radially outwards. The overflow section 76, located on the outer periphery of the active membrane 66, deforms and moves upwards, thereby creating a short-circuit connection between the pressure chamber 90 and the balance chamber 92, thus reducing cavitation noise. In this embodiment, radial reinforcing ribs 88 are provided along the transmission path of elastic deformation and even stress from the approximately central portion of the hydraulic absorption section 78 towards the overflow section 76. The transmission characteristics of elastic deformation and even stress from the approximately central portion of the hydraulic absorption section 78 towards the overflow section 76 can be tuned according to the size and shape of these radial reinforcing ribs 88. Specifically, for example, the radial reinforcing ribs 88 are formed with a sufficiently large cross-sectional shape, thereby enabling the overflow section 76 to perform overflow operations more efficiently based on the hydraulic pressure acting on the hydraulic absorption section 78. On the other hand, compared to the overall hydraulic absorption surface that functions as an active membrane in the hydraulic absorption section 78, the area of ​​the radial reinforcing ribs 88 is limited, specifically only a short length extending from the overflow section 76 towards the inner periphery. That is, the radial reinforcing ribs 88 extend only radially from the central portion of the hydraulic absorption section 78 towards the overflow section 76, and do not extend in other directions such as the circumferential direction. Therefore, the area area in the hydraulic absorption section 78 that effectively absorbs small hydraulic fluctuations relative to small amplitude vibrations can be adequately ensured, and this hydraulic fluctuation absorption effect is not significantly adversely affected by the presence of the radial reinforcing ribs 88, thus enabling it to function effectively.

[0140] In summary, radial reinforcing ribs 88 extending outward from the inner periphery of the retaining portion 70 toward the overflow portion 76 are provided on the active membrane 66. By adjusting the deformation rigidity caused by the radial reinforcing ribs 88, the threshold for the opening operation of the overflow portion 76 can be set. Therefore, for example, when engine vibration is input that has been tuned to the orifice passage 94, the lower through-hole 52 remains blocked by the overflow portion 76, thereby preventing the escape of hydraulic pressure through the lower through-hole 52 (reduction or even elimination of the pressure difference between the pressure chamber 90 and the balance chamber 92), thus effectively utilizing the vibration damping effect of the orifice passage 94. Furthermore, when the pressure in the pressure chamber 90, where cavitation is a problem, decreases, the overflow portion 76 operates with high precision, and the negative pressure in the pressure chamber 90 is rapidly reduced or even eliminated.

[0141] On the other hand, in this embodiment, the mass is increased by forming a protrusion 80 on the overflow portion 76, and / or by adjusting the circumferential free length of the overflow portion 76 to be shorter than the circumferential free length of the radial middle portion of the hydraulic absorption portion 78 through the outer peripheral abutment retaining portion 72, thereby suppressing unnecessary overflow in the overflow portion 76. In summary, by efficiently transmitting the elastic deformation of the hydraulic absorption portion 78 to the overflow portion 76 through the radial reinforcing ribs 88 as described above, overflow can be reliably detected, and the situation where the overflow portion 76 is prone to or unstable movement due to small pressure fluctuations, resulting in unwanted overflow, is suppressed. As a result, based on ensuring the fluid flow rate of the throttle orifice passage 94 when effectively reaching the vibration input that should be protected against vibration, and realizing the low-motion spring characteristics under the hydraulic absorption effect of small amplitude vibration input based on the elastic deformation of the hydraulic absorption portion 78, the overflow portion 76 can be used to prevent cavitation noise by ensuring reliable operation of the overflow mechanism when subjected to excessive impact loads. In addition, particularly in this embodiment, the protrusion 80 formed on the top abuts against the cover member 44, thereby limiting the displacement of the overflow section 76 during overflow operation, thus preventing excessive overflow operation of the overflow section 76 due to unnecessary large displacement.

[0142] However, the upward deformation of the movable membrane 66 relative to the negative pressure of the pressure chamber 90 can be adjusted to some extent by means of the radial reinforcing ribs 88. The effect of the negative pressure on the movable membrane 66 relative to the pressure chamber 90, in a manner similar to... Figure 12 The bow shape produces flexural deformation, and therefore the flexural deformation of this bow shape (deformation characteristics of only the circumferential central portion in the hydraulic absorption section 78) is controlled by radially extending radial reinforcing ribs 88, thereby enabling efficient regulation of the overflow flow. That is, the radially extending radial reinforcing ribs 88, for the circumferential central portion of the hydraulic absorption section 78 of the active membrane 66, can also utilize the rigidity of the vertical flexural deformation relative to the radial direction to control the flexural deformation of the bow shape of the active membrane 66 (e.g., suppression of excessive deformation of the central portion of the hydraulic absorption section 78, etc.).

[0143] Furthermore, by adjusting the deformation rigidity of the movable membrane 66 through the radial reinforcing ribs 88, the displacement speed of the overflow portion 76 when it opens or closes the lower through hole 52 due to deformation can be adjusted. This allows for adjustment of the impact intensity (force) on the inner wall of the overflow portion 76 receiving the recess 46.

[0144] Radial reinforcing ribs 88 protrude from the lower surface of the movable membrane 66, thereby applying a compressive force in the radial direction to the radially extending reinforcing ribs 88 during the bow-shaped flexural deformation of the overflow portion 76 during opening. Therefore, by using a compression spring along the length of the radially extending radial reinforcing ribs 88, the deformation characteristics (deformation rigidity, etc.) of the overflow portion 76 during opening can be efficiently adjusted. Furthermore, even with repeated opening of the overflow portion 76, tensile loads are unlikely to act on the radial reinforcing ribs 88, easily preventing damage to the narrow protrusions, i.e., the radial reinforcing ribs 88. In this embodiment, the radial reinforcing ribs 88 extend linearly in the radial direction, thus the influence of the radial reinforcing ribs 88 can be efficiently applied relative to the opening of the overflow portion 76 (flexural deformation of the movable membrane 66).

[0145] Only one radial reinforcing rib 88 is provided on each overflow portion 76. This prevents the radial reinforcing rib 88 from exerting an excessive influence on the deformation rigidity of the hydraulic absorption portion 78, thereby effectively achieving the vibration damping effect (hydraulic absorption effect) of the elastic deformation of the hydraulic absorption portion 78. Furthermore, the radial reinforcing rib 88 is positioned at the circumferential center of the overflow portion 76. Therefore, the deformation rigidity of the movable membrane 66 caused by the radial reinforcing rib 88 can be balanced circumferentially, for example, easily preventing adverse conditions such as deformation distortion during the opening and operation of the overflow portion 76.

[0146] Active membrane 66 facing the image Figure 12 When the deformation deforms into a convex bow shape as shown above, the deformation-limiting protrusion 84, located on the inner periphery side of the protrusion 80, can abut against the cover member 44 before the protrusion 80. Thus, the movable membrane 66 abuts against the cover member 44 in stages between the deformation-limiting protrusion 84 and the protrusion 80, reducing the impact force on the cover member 44 and decreasing impact noise. The upper surface area of ​​the deformation-limiting protrusion 84 is smaller than that of the protrusion 80, and at least the front end is tapered, resulting in less impact when it abuts against the cover member 44, making impact noise less of a problem. Furthermore, radial reinforcing ribs 88 are provided on the lower side of the deformation-limiting protrusion 84. For example, the radial reinforcing ribs 88 reduce the impact speed of the deformation-limiting protrusion 84 against the cover member 44, thereby preventing the generation of impact noise.

[0147] The movable membrane 66, which is displaced upward due to the negative pressure of the pressure chamber 90, displaces downward and abuts against the inner surface of the bottom wall of the receiving recess 46 when positive pressure is applied to the pressure chamber 90. In this case, the deformation mode of the movable membrane 66, which is deformed into an arc shape, when it returns to its initial shape is controlled by the radial reinforcing ribs 88, thereby reducing the impact noise caused by the movable membrane 66 striking the partition member body 42.

[0148] Furthermore, an annular buffer protrusion 86 is provided on the lower surface of the movable membrane 66, so the impact sound when the movable membrane 66 abuts against the inner surface of the bottom wall of the receiving recess 46 is also reduced due to the buffering effect of the annular buffer protrusion 86. The protrusion height of the annular buffer protrusion 86 is larger than that of the radial reinforcing ribs 88, so it can preferentially abut against the main body of the partition member 42 and obtain a greater buffering effect.

[0149] Figure 13 The movable membrane 100, which constitutes the rubber elastic plate of the engine bracket according to the second embodiment of the present invention, is shown. In the following description, components and parts substantially the same as those in the first embodiment are omitted from description as they are labeled with the same reference numerals in the figures. Furthermore, regarding… Figure 13 Other parts of the engine mount, not shown, are illustrated with the same construction as in the first embodiment, and therefore are omitted from description.

[0150] Radial reinforcing ribs 102 are provided on the upper surface of the hydraulic absorption portion 78 of the active membrane 100. The radial reinforcing ribs 102 are, for example, formed as an inverted version of the radial reinforcing ribs 88 of the first embodiment, and tapered upwards at their front ends. The radial reinforcing ribs 102 extend outwards from the inner peripheral abutment holding portion 70 toward the overflow portion 76. In this embodiment, they are provided radially between the inner peripheral abutment holding portion 70 and the protrusion 80, so that both ends are continuous on the inner peripheral abutment holding portion 70 and the protrusion 80. The radial reinforcing ribs 102 are respectively provided on the inner peripheral side and the outer peripheral side of the deformation limiting protrusion 84. The protrusion height dimension of the radial reinforcing ribs 102 is smaller than the protrusion height dimension of any of the inner peripheral abutment holding portion 70, the protrusion 80, and the deformation limiting protrusion 84. The protrusion height dimension and width dimension of the radial reinforcing ribs 102 are smaller than the protrusion height dimension and width dimension of the reinforcing connecting portion 74.

[0151] The movable membrane 100, constructed according to the above-described embodiment, can be used in place of the movable membrane 66 in the engine mount 10 of the first embodiment. Similar to the first embodiment, the radial reinforcing ribs 102 in the movable membrane 100 of this embodiment contribute to the deformability rigidity of the movable membrane 100, thereby controlling the displacement of the overflow portion 76, suppressing the influence of the hydraulic absorption portion 78 on the absorption function of small pressure fluctuations, and controlling the opening manner of the overflow portion relative to the reduced internal pressure of the pressure chamber.

[0152] It should be noted that both radial reinforcing ribs 102 forming the upper surface of the rubber elastic plate shown in this embodiment and radial reinforcing ribs 88 forming the lower surface of the rubber elastic plate shown in the first embodiment can be provided, or only one of them can be provided.

[0153] The embodiments of the present invention have been described in detail above, but the present invention is not limited to this specific description. For example, in the described embodiments, three hydraulic absorption sections 78 and three overflow sections 76 are each formed. The number of hydraulic absorption sections and overflow sections is not particularly limited; there may be one or more than two sections.

[0154] A plurality of radial reinforcing ribs 88 are provided on an overflow portion 76. In this case, the plurality of radial reinforcing ribs 88 are preferably arranged symmetrically in the circumferential direction with respect to the circumferential center of the overflow portion 76. For example, when the number of radial reinforcing ribs 88 is even, the same number can be arranged on both sides of the circumferential direction away from the circumferential center of the overflow portion 76.

[0155] Radial reinforcing ribs are not limited to a straight-line extending shape; for example, they can be circumferentially curved, bent, or otherwise extended radially. Furthermore, radial reinforcing ribs do not necessarily extend along a radial line; for example, they can be inclined relative to the radial direction and extend radially.

[0156] The protruding height of the radial reinforcing ribs can be larger than that of the annular buffer. Furthermore, the width of the radial reinforcing ribs can also be larger than that of the annular buffer. In short, the cross-sectional shape and cross-sectional area (protruding height and width) of the radial reinforcing ribs are set to appropriately adjust the deformation rigidity of the active membrane (the opening and working characteristics of the elastic deformation region). It should be noted that the cross-sectional shape of the radial reinforcing ribs does not need to be constant along the length direction; the height, width, and other cross-sectional shapes can vary locally or gradually. Additionally, the radial reinforcing ribs can be broken along the length direction. Further, in the described embodiment, the radial reinforcing ribs extend from approximately the inner circumferential end of the hydraulic absorption section to approximately the outer circumferential end, but the positions of the inner and outer circumferential ends of the radial reinforcing ribs can be set by tuning and are therefore not limited. However, when considering the elastic deformation and stress transmission effects to the overflow section as described above, it is preferable that the inner circumferential end of the radial reinforcing rib extends further to the inner circumferential side than the radial center of the hydraulic absorption section, and preferably that the outer circumferential end reaches the protrusion.

[0157] The radial reinforcing ribs are preferably a cross-sectional shape in which the width dimension decreases toward the protruding front end and tapers towards the front end, but for example, they can also be a roughly rectangular cross-sectional shape that protrudes with a substantially constant width dimension.

[0158] It is also considered to utilize the protrusion located in the overflow section as a mass-spring type. That is, by using the protrusion as a mass, a mass-spring type is constructed in which the overflow sections on both sides of the protrusion's circumference and the hydraulic absorption section on the inner circumference of the protrusion function as springs. The resonant frequency of this mass-spring type is set considering factors such as the tuning frequency of the throttle orifice passage. By utilizing the resonance of the mass-spring type, for example, unnecessary opening of the overflow section in the frequency domain where the anti-vibration effect caused by the throttle orifice passage and the hydraulic absorption section is expected can be prevented, and rapid opening of the overflow section can be achieved when a large impact load is input. It should be noted that, in addition to utilizing the protrusion, deformation-limiting protrusions can also be used as masses to replace the protrusion, or, in addition to the protrusion, high-density components such as metal can be fixedly installed in the overflow section using masses.

[0159] In a rubber elastic plate, protrusions are not necessary. For example, a protrusion protruding toward the elastic deformation area can be provided on the displacement limiting portion (cover member 44) on the pressure chamber side covering the elastic deformation area of ​​the rubber elastic plate, thereby limiting the amount of deformation of the elastic deformation area toward the pressure chamber side. It should be noted that deformation limiting protrusions are not necessary in a rubber elastic plate. In addition, in a rubber elastic plate, the reinforcing connecting portion 74 extending radially inward from the circumferentially extending outer peripheral abutment holding portion 72 does not necessarily need to have an outer peripheral portion, and the hydraulic absorption portion 78 can be formed in a region that extends in a ring shape throughout the entire circumference.

[0160] The radially spaced cushioning protrusions 82 provided on the upper surface of the protrusion 80 can be omitted. When the radially spaced cushioning protrusions 82 are omitted, for example, it is preferable that the protrusion is formed into a tapered shape at the front end, or other structures such as circumferentially extending cushioning protrusions or spot-shaped cushioning protrusions provided on the upper surface of the protrusion are used to reduce impact noise.

[0161] The specific construction of the first mounting component 12, the second mounting component 14, the main rubber elastomer 16, and the flexible membrane 36 is not particularly limited, and publicly known constructions can be appropriately applied in existing fluid-sealed vibration damping devices.

Claims

1. A fluid-sealed vibration damping device (10), wherein, The fluid-sealed vibration damping device (10) is provided with a pressure chamber (90) and a balance chamber (92), which are filled with incompressible fluid. The fluid-sealed vibration damping device (10) has a communication port (52) formed on the separating member (40) that separates the pressure chambers (90) and the balance chamber (92) to connect the pressure chambers (90) and the balance chamber (92). A rubber elastic plate (66, 100) is arranged to cover the communication port (52) from the side of the pressure chamber (90). Based on the elastic deformation of the rubber elastic plate (66, 100) caused by the pressure difference between the pressure chamber (90) and the balance chamber (92) applied to one side of each of the rubber elastic plates (66, 100), it performs a function of absorbing small pressure fluctuations. In the fluid-sealed vibration damping device (10), a peripheral abutment retaining part (72) is partially provided circumferentially on the outer periphery of the rubber elastic plate (66, 100). This peripheral abutment retaining part (72) is held in a state of overlapping with the separating member (40), and, An elastic deformation region (76) is provided circumferentially between the outer peripheral abutment holding portion (72) in the rubber elastic plate (66, 100). The elastic deformation region (76) is separated from the partition member (40) based on the pressure difference between the pressure chamber (90) and the balance chamber (92), thereby allowing fluid to flow from the balance chamber (92) to the pressure chamber (90) through the communication port (52). Radial reinforcing ribs (88, 102) are formed protruding from at least one surface of the rubber elastic plate (66, 100). These radial reinforcing ribs (88, 102) extend outward from the inner peripheral abutment holding portion (70), which is held in a state of overlapping with the separating member (40), toward the elastic deformation region (76). A protrusion (80) protruding toward the pressure chamber (90) is provided in the elastic deformation region (76). The pressure chamber (90) side of the protrusion (80) is covered by a displacement limiting part (44) provided on the partition member (40). The radial reinforcing ribs (88, 102) are provided at positions corresponding to the protrusion (80) in the circumferential direction of the rubber elastic plate (66, 100).

2. The fluid-sealed vibration damping device (10) according to claim 1, wherein, The outer peripheral ends of the radial reinforcing ribs (88, 102) are located at the circumferential center of each of the elastic deformation regions (76).

3. The fluid-sealed vibration damping device (10) according to claim 1 or 2, wherein, A radial reinforcing rib (88, 102) is provided in one of the elastic deformation regions (76).

4. The fluid-sealed vibration damping device (10) according to claim 1 or 2, wherein, The radial reinforcing ribs (88) protrude from the surface of the rubber elastic plate (66) on the side of the balance chamber (92).

5. The fluid-sealed vibration damping device (10) according to claim 4, wherein, On the surface of the balance chamber (92) side in the rubber elastic plate (66), there is an annular cushioning protrusion (86) extending in the circumferential direction, and the protrusion height dimension of the radial reinforcing rib (88) is smaller than the protrusion height dimension of the annular cushioning protrusion (86).

6. The fluid-sealed vibration damping device (10) according to claim 1 or 2, wherein, The radial reinforcing ribs (88, 102) extend in a generally radial straight line toward the rubber elastic plate (66, 100).

7. The fluid-sealed vibration damping device (10) according to claim 1, wherein, The protruding front end face of the protrusion (80) is formed with a surface shape corresponding to the displacement limiting part (44). The protruding front end face of the protrusion (80) is provided with radially extending cushioning protrusions (82) along the radial direction of the rubber elastic plate (66, 100).

8. The fluid-sealed vibration damping device (10) according to claim 1 or 7, wherein, On the inner circumferential side of the protrusion (80) in the rubber elastic plate (66, 100), a deformation-limiting protrusion (84) is provided, arranged radially alongside the protrusion (80). The radial reinforcing ribs (88, 102) extend continuously in the radial direction across these protrusions (80) and deformation limiting protrusions (84), and extend to a position further inward than the deformation limiting protrusions (84).

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