Vibration control device

Abstract

To provide a vibration control device of a new structure, capable of positioning a first member and a second member arranged on a vibration transmission route while holding the first and second members at an appropriate connection position with a simple structure.SOLUTION: A vibration control device 10 comprises a vibration control rubber 26 interposed between members constituting a vibration transmission system, where a first member 24 and a second member 16 that are arranged on a vibration transmission path of the vibration transmission system and to which input vibration is exerted via the vibration control rubber 26, are interconnected by a pin 34 protruding from the first member 24 and inserted into a pin insertion hole 114 of the second member 16, and a connection member 122 attached to the pin 34.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an anti-vibration device for use in engine mounts of automobiles, etc. [Background technology]

[0002] Conventionally, there are known anti-vibration devices used in automobile engine mounts, etc. As disclosed in, for example, JP 2017-082991 A (Patent Document 1), the anti-vibration device has a structure in which a first mounting member and a second mounting member are connected by a main rubber elastic body.

[0003] In addition, in the vibration isolation device of Patent Document 1, guide parts provided on both sides of the second mounting member in the width direction are inserted into guide grooves of the bracket, so that the bracket is attached laterally to the second mounting member. In the embodiment of Patent Document 1, a covering rubber is provided on the surface of the guide part, and the guide part is rubber-pressed into the guide groove via the covering rubber. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2017-082991 A Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, the vibration isolation device shown in Patent Document 1 has a crimping pin protruding from the tip of the guide groove in the guide part of the second mounting member, and the crimping pin is inserted into the crimping hole of the bracket and compressed in the axial direction, so that the crimping pin is pressed against the inner surface of the crimping hole and crimped and fixed. This prevents the second mounting member from coming off the bracket, and holds the bracket attached to the second mounting member in a predetermined position.

[0006] However, when compressing the crimping pin (crimping), it is difficult to hold the second mounting member and the bracket in an appropriate relative position. For example, in an embodiment of Patent Document 1 in which the guide part is rubber-pressed into the guide groove via a rubber covering, the relative position between the second mounting member and the bracket may change due to the input during crimping and fixing, if the holding force provided by the rubber pressing into the guide groove of the guide part is not enough. It is also possible to perform crimping while biasing the guide part in the press-in direction using a piston or the like, but in this case, input is required in two directions, the direction in which the guide part is biased and the direction in which the crimping pin is compressed, and special equipment is required for processing.

[0007] The problem to be solved by the present invention is to provide a vibration-damping device of a novel structure that can position a first member and a second member arranged on a vibration transmission path while maintaining them in an appropriate connected position with a simple structure. [Means for solving the problem]

[0008] The following describes preferred embodiments for understanding the present invention, but the embodiments described below are merely illustrative and may be combined with one another as appropriate, and the multiple components described in each embodiment may be recognized and used independently as far as possible, and may also be combined with any of the components described in another embodiment as appropriate. As a result, the present invention is not limited to the embodiments described below, and various other embodiments may be realized.

[0009] The first aspect is a vibration-damping device having vibration-damping rubber interposed between members that constitute a vibration transmission system, in which a first member and a second member are arranged on the vibration transmission path of the vibration transmission system and to which input vibration is applied via the vibration-damping rubber, and are interconnected by a pin that protrudes from the first member and is inserted into a pin insertion hole of the second member, and a connecting member that is attached to the pin.

[0010] In the vibration isolation device constructed according to this aspect, the first member and the second member are connected by attaching the connecting member to the pin, and the first member and the second member can be connected easily with less force than in the case where the pin inserted into the pin insertion hole is compressed and crimped to the inner surface of the pin insertion hole. Moreover, since there is no need to deform the pin, there is a high degree of freedom in the selection of the material of the pin and the first member that includes it.

[0011] Furthermore, when compressing the pin and crimping it to the inner surface of the pin insertion hole, it is necessary to set the distance between the pin and the inner surface of the pin insertion hole with high precision, and in particular the inner diameter of the pin insertion hole needs to be controlled with high precision. However, by using a connecting structure in which a connecting member is attached to the pin, the required precision of the inner diameter of the pin insertion hole is lower, making manufacture easier.

[0012] Furthermore, in a connection structure in which a connecting member is attached to a pin, it is easy to know whether the connection is appropriate based on whether the pin is inserted to an appropriate position in the connecting member. Therefore, inspection of whether the connection between the first member and the second member is appropriate can be performed by a simple visual inspection, and the connection work can be simplified.

[0013] In addition, since the input vibration is applied to the first and second members connected by the connecting member through the vibration-isolating rubber, the vibration acting on the connecting structure formed by the connecting member is reduced by the vibration-isolating effect of the vibration-isolating rubber. Therefore, the first and second members are connected by the connecting member with high reliability, and separation of the first and second members is effectively prevented.

[0014] In a second aspect, in the vibration-damping device described in the first aspect, the connecting member has an outer peripheral portion which is a ring-shaped abutment portion that is superimposed on the second member around the pin insertion hole, and an inner peripheral portion which is tapered toward the tip of the pin toward the inner circumference and is an attachment portion that is attached in an externally inserted state to the pin.

[0015] With the vibration isolation device constructed according to this aspect, by checking that the abutment portion is overlapped around the pin insertion hole in the second member, it is possible to easily confirm that the connecting member is attached to the pin in an appropriate position and that the first member and the second member are appropriately connected. In addition, since the inner peripheral portion of the connecting member is a tapered attachment portion, the pin can be easily inserted into the inner hole of the connecting member, and the pin is easily prevented from coming out of the connecting member.

[0016] A third aspect is the vibration isolation device according to the first or second aspect, wherein the pin and the connecting member are formed from the same material.

[0017] According to a vibration-isolating device constructed in accordance with this embodiment, galvanic corrosion is unlikely to occur between the pin and the connecting member, and durability is improved.

[0018] A fourth aspect is the vibration-proof device according to any one of the first to third aspects, wherein a gap is provided between the pin and an inner circumferential surface of the pin insertion hole.

[0019] With an anti-vibration device constructed according to this aspect, the pin can be easily inserted into the pin insertion hole, and the dimensional error of the outer diameter of the pin and the inner diameter of the pin insertion hole can be more widely tolerated. In addition, since the first member and the second member are connected by attaching a connecting member to the pin, even if a gap is provided between the pin and the pin insertion hole, the impact on the strength of the connection between the first member and the second member is small.

[0020] A fifth aspect is an anti-vibration device described in any one of the first to fourth aspects, wherein the second member has an engagement groove, the first member has an engagement portion that is inserted into the engagement groove, an engagement rubber is provided between the engagement groove and the engagement portion, the engagement portion is rubber-pressed into the engagement groove via the engagement rubber, and the pin is provided protruding from the engagement portion in the direction of insertion of the engagement portion into the engagement groove.

[0021] According to the vibration-proof device constructed according to this aspect, the pin protruding from the fitting portion in the press-fitting direction is inserted into the pin insertion hole opening deep into the fitting groove, and a connecting member is attached to the pin, thereby restricting the fitting portion rubber-pressed into the fitting groove from moving in the direction of coming out of the fitting groove, thereby connecting the first member having the fitting portion and the second member having the fitting groove to each other. Also, assembling the first member and the second member by inserting the fitting portion into the fitting groove causes the pin to be inserted into the pin insertion hole, the number of steps in the assembling operation of the first member and the second member can be reduced. Effect of the Invention

[0022] According to the present invention, in a vibration isolation device, a first member and a second member arranged on a vibration transmission path can be positioned while being held in an appropriate connecting position with a simple structure. [Brief description of the drawings]

[0023] [Figure 1] FIG. 1 is a perspective view showing an engine mount according to a first embodiment of the present invention; [Diagram 2] FIG. 2 is a perspective view showing the engine mount of FIG. 1 from a different angle. [Diagram 3] FIG. 3 is a vertical cross-sectional view of the engine mount shown in FIG. 1, which corresponds to the cross-section III-III of FIG. [Figure 4] IV-IV cross section of Figure 3 [Diagram 5] VV cross section of Figure 3 [Figure 6] A vertical cross-sectional view of the mount body that constitutes the engine mount shown in Figure 1. [Figure 7] FIG. 7 is a perspective view of a vibration-isolating base constituting the mount body shown in FIG. [Figure 8] FIG. 7 is a perspective view of a cup member constituting the mount body shown in FIG. [Figure 9] IX-IX cross section of Figure 3 [Figure 10] Cross-sectional view of Figure 9 [Figure 11] FIG. 2 is a perspective view of a push nut that constitutes the engine mount shown in FIG. [Figure 12] Left side view of the push nut shown in Figure 11 [Figure 13] XIII-XIII sectional view of Figure 12 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0025] 1 to 5 show an engine mount 10 for an automobile as a first embodiment of a vibration-proof device constructed according to the present invention. The engine mount 10 has a structure in which an inner bracket 14 and an outer bracket 16 as a second member are attached to a mount body 12 shown in Fig. 6. The mount body 12 has a structure in which a vibration-proof base 18 shown in Fig. 7 is rubber-pressed into a cup member 20 shown in Fig. 8. In the following description, in principle, the up-down direction refers to the up-down direction in Fig. 3 which is the mount central axial direction which is the main load input direction, the front-rear direction refers to the left-right direction in Fig. 3, and the left-right direction refers to the left-right direction in Fig. 4.

[0026] The vibration-isolating base 18 has a structure in which a first mounting member 22 and a second mounting member 24 as a first member are connected by a main rubber elastic body 26 as a vibration-isolating rubber. As shown in Figures 3, 4 and 6, the first mounting member 22 is generally cylindrical or has an inverted truncated cone shape that decreases in diameter downward, and is provided with a screw hole 28 that opens to the top surface. The first mounting member 22 is a high-rigidity member and may be formed of, for example, fiber-reinforced synthetic resin, but is preferably formed of a metal such as an aluminum alloy.

[0027] 3 to 6, the second mounting member 24 is a generally rounded rectangular cylinder with arc-shaped corners, and has a flat shape with a pair of long sides extending in the front-rear direction and a pair of short sides extending in the left-right direction when viewed in the axial direction. The second mounting member 24 also has a flange-like portion 30 protruding from the upper end toward the outer periphery, and fitting portions 32 extending linearly in the left-right direction are integrally formed on both the front and rear outer sides of the flange-like portion 30 provided on the pair of short sides.

[0028] The fitting portion 32 is generally rectangular prism-shaped, with the vertical width gradually decreasing toward the left. A cylindrical pin 34 protruding toward the left from the left end face of the fitting portion 32 is integrally provided on the second mounting member 24. The second mounting member 24 is a highly rigid member, and similar to the first mounting member 22, is preferably made of fiber-reinforced synthetic resin, metal, or the like. The second mounting member 24 has a larger diameter than the first mounting member 22.

[0029] As shown in Fig. 6, the first mounting member 22 is disposed above the second mounting member 24 on approximately the same central axis, and a main rubber elastic body 26 is disposed between the first mounting member 22 and the second mounting member 24. The main rubber elastic body 26 is approximately frustum-shaped with an outer circumferential surface tapered to a larger diameter downward, and the first mounting member 22 is inserted into the upper end, which is the small diameter end, and vulcanization-bonded thereto, while the second mounting member 24 is superimposed and vulcanization-bonded to the outer circumferential surface of the lower end, which is the large diameter end. In this way, the main rubber elastic body 26 is formed as an integrally vulcanization-molded product including the first mounting member 22 and the second mounting member 24, and the vibration-proof base 18 of this embodiment is constituted by the integrally vulcanization-molded product of the main rubber elastic body 26. The second mounting member 24, which is fixed to the main rubber elastic body 26, has an upper part integrally formed with a fixing part 40 that protrudes toward the inner circumference, and the inner diameter of the upper part where the fixing part 40 is provided is smaller than the inner diameter of the lower part (press-fitted cylindrical part 42) free from the fixing part 40. The inner peripheral surface of the fixing part 40 is tapered so that the diameter decreases downward.

[0030] A recess 44 that opens downward is formed in the main rubber elastic body 26. The recess 44 is shaped like an inverted cone with a smaller diameter toward the upper base side, and is provided on the inner periphery side of the fastening portion 40 of the second mounting member 24. By forming the recess 44, the portion of the main rubber elastic body 26 that connects the first mounting member 22 and the second mounting member 24 has a tapered shape in which both the inner diameter and the outer diameter increase downward.

[0031] The press-fit tube portion 42, which is the lower portion of the second mounting member 24, is covered with a rubber layer 46 integrally formed with the main rubber elastic body 26. The rubber layer 46 is provided so as to cover the entire inner peripheral surface and the lower portion of the outer peripheral surface of the press-fit tube portion 42. The inner peripheral rubber 48 covering the inner peripheral surface of the press-fit tube portion 42 in the rubber layer 46 is thicker at the upper portion than at the lower portion, and the thicker outer peripheral portion of the upper portion is fixed to the lower surface of the fixing portion 40, and is integrally continuous with the main rubber elastic body 26 at the inner peripheral end portion of the upper portion. In addition, the portion of the rubber layer 46 covering the outer peripheral surface of the press-fit tube portion 42 is made of a press-fit rubber 50. The press-fit rubber 50 is formed so as to cover substantially the entire outer peripheral surface of the press-fit tube portion 42. The outer peripheral surface of the lower portion of the press-fit rubber 50 is tapered so as to become smaller in diameter downward.

[0032] The portion of the rubber layer 46 covering the lower surface of the press-fit tubular portion 42 is a seal rubber 52. The seal rubber 52 is formed continuously around the entire circumference with a tapered cross-sectional shape that narrows radially downward. The portion of the seal rubber 52 with the maximum protruding height is disposed at a position that overlaps with the lower surface of the press-fit tubular portion 42 when projected in the up-down direction. The maximum thickness (protruding height) of the seal rubber 52 is made larger than the thicknesses of the inner circumferential rubber 48 and the press-fit rubber 50.

[0033] 7, a rubber fitting 54 formed integrally with the main rubber elastic body 26 is fixed to the fitting portion 32 of the second mounting member 24. The rubber fitting 54 is provided on a portion of the fitting portion 32 in the left-right direction, and covers both the front and rear and the top and bottom of the fitting portion 32. In this embodiment, a step is provided in the portion of the rubber fitting 54 covering both the top and bottom of the fitting portion 32, and the front and rear outer sides of the step are thicker than the inner side. In this embodiment, the rubber fitting 54 has a right side portion with a substantially constant top-bottom outer dimension in the left-right direction, and a left side portion with a gradually smaller top-bottom outer dimension toward the left, and is thick in the middle in the left-right direction.

[0034] 8, the cup member 20 is integrally provided with a peripheral wall portion 56 having a generally rounded rectangular tubular shape corresponding to the second mounting member 24, and a bottom wall portion 58 provided to close a lower opening of the peripheral wall portion 56. Although the cup member 20 is a hard member, it is preferable that radial bending deformation is allowed to a certain extent, particularly at the base press-fit portion 62, and although it may be made of metal, it is preferably formed of a hard synthetic resin (including fiber-reinforced synthetic resin).

[0035] The peripheral wall portion 56 is integrally provided with a partition insertion portion 60 that protrudes upward from the outer peripheral end of the bottom wall portion 58, and a base press-fit portion 62 that protrudes upward from the outer peripheral end of the partition insertion portion 60. The base press-fit portion 62 is thinner than the partition insertion portion 60, and preferably has a radial thickness dimension that is half or less than that of the partition insertion portion 60.

[0036] A through hole 63 that penetrates in the up-down direction is formed in the bottom wall portion 58. By forming this through hole 63, the bottom wall portion 58 is formed into an inner flange shape that protrudes inwardly at the lower end of the peripheral wall portion 56.

[0037] 3 and 4, the press-fit tubular portion 42 of the second mounting member 24 in the vibration-isolating base 18 is axially inserted into the base press-fit portion 62 of the peripheral wall portion 56 of the cup member 20. Then, the press-fit rubber 50 of the rubber layer 46 is compressed between the outer peripheral surface of the press-fit tubular portion 42 of the second mounting member 24 and the inner peripheral surface of the base press-fit portion 62 of the cup member 20. In this manner, the second mounting member 24 and the cup member 20 are positioned relative to each other, with the press-fit tubular portion 42 of the second mounting member 24 being rubber press-fitted into the base press-fit portion 62 of the cup member 20 via the press-fit rubber 50.

[0038] The gap between the press-fit tube portion 42 of the second mounting member 24 and the peripheral wall portion 56 of the cup member 20 is liquid-tightly sealed by the seal rubber 52 and the press-fit rubber 50, which are part of the rubber layer 46. That is, the seal rubber 52 covering the lower surface, which is the insertion tip surface of the second mounting member 24 into the cup member 20, is compressed between the upper and lower opposing surfaces of the lower surface of the press-fit tube portion 42 of the second mounting member 24 and the upper surface of the partition insertion portion 60 of the cup member 20, thereby liquid-tightly sealing between the upper and lower opposing surfaces of the press-fit tube portion 42 and the partition insertion portion 60. The press-fit rubber 50 is compressed between the radially opposing surfaces of the outer circumferential surface of the press-fit tube portion 42 and the inner circumferential surface of the base press-fit portion 62, thereby liquid-tightly sealing between the radially opposing surfaces of the press-fit tube portion 42 and the base press-fit portion 62.

[0039] A partition member 64 and a flexible film 66 are disposed between the vibration-isolating base 18 and cup member 20 thus assembled, thereby forming the mount body 12. As shown in Figures 3 and 4, the partition member 64 is shaped as a whole in a generally rectangular plate shape with rounded corners, and has a structure in which a cover metal fitting 70 is superimposed on and fixed to the upper surface of a partition member main body 68.

[0040] The partition member main body 68 is generally in the form of a thick plate, and a circumferential groove 72 is formed around the outer periphery of the partition member 68, extending in the circumferential direction and opening on the upper surface. The circumferential groove 72 extends in the circumferential direction for a length less than one revolution, and as shown in FIG. 4, a lower communication port 74 is formed at one circumferential end portion thereof, penetrating the bottom wall portion. In addition, a storage recess 76 opening on the upper surface and a lightening recess 78 opening on the lower surface are formed on the inner circumferential side of the partition member main body 68 from the circumferential groove 72. A columnar central insertion portion 80 protruding upward from the bottom wall is provided at the center of the storage recess 76. A plurality of lower through holes (not shown) penetrating in the vertical direction are formed in the bottom wall of the storage recess 76.

[0041] A movable membrane 84 is accommodated in the accommodation recess 76. The movable membrane 84 is formed of a rubber elastic body, and has a generally rounded rectangular plate shape corresponding to the accommodation recess 76. An insertion hole 86 penetrating in the vertical direction is formed in the central part of the movable membrane 84, and when accommodated in the accommodation recess 76, the central insertion part 80 of the partition member main body 68 is inserted into the insertion hole 86, thereby positioning the movable membrane 84 within the accommodation recess 76. The movable membrane 84 has a thick outer circumferential end and a periphery of the insertion hole 86, and a thinner radial middle part.

[0042] A lid fitting 70 is superimposed on the upper surface of the partition member main body 68. The lid fitting 70 is in the form of a flat plate with rounded rectangular corners corresponding to the partition member main body 68 when viewed in the vertical direction, and is made of a metal such as an aluminum alloy or stainless steel. The lid fitting 70 has an upper communication port 88 that penetrates the outer circumferential end in the vertical direction as shown in Figures 3 and 5, and also has a plurality of upper through holes 90 that penetrate the inner circumferential portion in the vertical direction as shown in Figure 5.

[0043] As shown in Figures 3 and 4, the cover fitting 70 is fixed to the partition member main body 68 in a state where it is superimposed on the upper surface of the partition member main body 68, and the partition member 64 is constituted by the partition member main body 68, the movable membrane 84, and the cover fitting 70. By superimposing the cover fitting 70 on the partition member main body 68, the upper opening of the circumferential groove 72 is covered by the cover fitting 70 to form a tunnel-like passage. In addition, the upper opening of the accommodation recess 76 is covered by the cover fitting 70 to form a void, and the movable membrane 84 is accommodated in this void. The thick-walled inner and outer circumferential ends of the movable membrane 84 are compressed in the vertical direction between the bottom wall of the accommodation recess 76 in the partition member main body 68 and the cover fitting 70, and the upper surface of the thin-walled radially middle portion is spaced downward from the cover fitting 70.

[0044] The partition member 64 has an upper portion inserted into the press-fit tubular portion 42 of the second mounting member 24 of the vibration-isolating base 18, and a lower portion inserted into the partition insertion portion 60 of the cup member 20, and is disposed so as to spread in the vertically orthogonal direction between the vibration-isolating base 18 and the cup member 20. In this embodiment, the outer circumferential surface of the partition member main body 68 is fitted into the press-fit tubular portion 42 of the second mounting member 24 via the inner circumferential rubber 48, and is also fitted into the partition insertion portion 60 of the cup member 20, thereby positioning the partition member 64 with respect to the vibration-isolating base 18 and the cup member 20. In the stand-alone state of the mount main body 12 before the outer bracket 16 is attached as shown in FIG. 6, the outer circumferential end of the cover metal fitting 70 is spaced downward from the portion of the inner circumferential rubber 48 that covers the underside of the fixing portion 40.

[0045] A flexible film 66 is disposed below the partition member 64. The flexible film 66 is formed of rubber or resin elastomer, has a thin dome shape, and has flexibility that allows deformation in the thickness direction. A relatively thick annular holding portion 92 is provided at the outer peripheral end of the flexible film 66. The holding portion 92 is sandwiched in the vertical direction over the entire circumference between the partition member main body 68 and the bottom wall portion 58 of the cup member 20, so that the flexible film 66 is disposed so as to cover the lower part of the partition member 64. The thin inner peripheral portion of the flexible film 66 is exposed downward through the through hole 63 of the bottom wall portion 58 of the cup member 20, and the through hole 63 allows deformation such as downward bulging.

[0046] Between the vibration-isolating base 18 and the partition member 64, a pressure-receiving chamber 94 is formed as a fluid chamber, the wall of which is partly formed by the main rubber elastic body 26, and in which internal pressure fluctuations are induced when vibration is input. Between the partition member 64 and the flexible membrane 66, a balance chamber 96 is formed as a fluid chamber, the wall of which is partly formed by the flexible membrane 66, and in which volume change is permitted. The pressure-receiving chamber 94 and the balance chamber 96 are filled with an incompressible fluid, such as water, ethylene glycol, alkylene glycol, silicone oil, or a mixture thereof. In the mount body 12, the gap between the vibration-isolating base 18 and the cup member 20 is sealed by the rubber layer 46 including the seal rubber 52, and the gap between the cup member 20 and the partition member 64 is sealed by the holding portion 92 of the flexible membrane 66, preventing leakage of the incompressible fluid filled inside.

[0047] The circumferential groove 72 of the partition member 64 communicates with the pressure-receiving chamber 94 through the upper communication port 88 and with the equilibrium chamber 96 through the lower communication port 74, and an orifice passage 98 that communicates between the pressure-receiving chamber 94 and the equilibrium chamber 96 is formed by the circumferential groove 72 and the upper and lower communication ports 88, 74. The tuning frequency of the orifice passage 98, which is the resonant frequency of the flowing fluid, is set to the frequency of the vibration to be damped, and is tuned to the frequency of low-frequency vibration such as engine shake, for example.

[0048] The movable membrane 84 of the partition member 64 has an upper surface to which the fluid pressure in the pressure-receiving chamber 94 is applied through the upper through hole 90, and a lower surface to which the fluid pressure in the equilibrium chamber 96 is applied through a lower through hole (not shown). When the relative pressure between the pressure-receiving chamber 94 and the equilibrium chamber 96 fluctuates, the radial middle portion of the movable membrane 84 deforms in the vertical direction, which is the thickness direction, thereby performing the function of transmitting fluid pressure between the pressure-receiving chamber 94 and the equilibrium chamber 96.

[0049] As shown in Figs. 1 to 5 and 9 and 10, an inner bracket 14 and an outer bracket 16 are attached to the mount body 12. The inner bracket 14 is formed as a thick plate extending in the left-right direction as a whole, and in this embodiment, the right end portion is attached to the first attachment member 22, and the left end portion is attached to the power unit of the vehicle. The right end portion of the inner bracket 14 in this embodiment is fixed to the first attachment member 22 by a bolt 104 screwed into the screw hole 28. The left end portion of the inner bracket 14 attached to the power unit is wider in the front-rear direction than the right end portion, and a plurality of first fastening holes 106 are formed penetrating the inner bracket 14 in the up-down direction. The inner bracket 14 is desirably formed of a metal such as iron, and is a highly rigid member.

[0050] The outer bracket 16 is provided with a mount receiving space 108 into which the mount body 12 is inserted and assembled. The mount receiving space 108 is recessed and opens to the right, and has a pair of fitting grooves 110, 110 opening on the inner surface of the front and rear walls. The fitting groove 110 extends linearly in the left-right direction, and in this embodiment, the vertical dimension increases toward the right. The fitting groove 110 reaches the right end of the outer bracket 16 and opens toward the right, but does not reach the left end. To the left of the fitting groove 110, a back wall portion 112 is provided that crosses the left-right direction and expands. A pin insertion hole 114 corresponding to the pin 34 of the second mounting member 24 is formed in the back wall portion 112 of the outer bracket 16, penetrating the left-right direction. In this embodiment, the pin insertion hole 114 has a substantially constant diameter on the right side and a larger diameter on the left side toward the left, and the inner surface of the left side is a tapered surface. The pin insertion hole 114 has a diameter slightly larger than that of the pin 34 over its entire length in the left-right direction.

[0051] As shown in Figures 1 and 4, a window 115 is formed in the left wall of the mount accommodating cavity 108 in the outer bracket 16, penetrating the upper part in the left-right direction. The outer bracket 16 is provided with a pair of attachment pieces 116, 116 that protrude forward and backward at the lower end. Each attachment piece 116 is formed with a second fastening hole 117 that penetrates in the vertical direction, as shown in Figures 1 to 3. As shown in Figures 3 and 4, an open hole 118 is formed in the lower wall of the mount accommodating cavity 108 in the outer bracket 16, penetrating in the vertical direction, and the open hole 118 allows downward deformation of the flexible membrane 66.

[0052] The outer bracket 16 is attached to the second mounting member 24 side of the mount body 12 by inserting the mount body 12 into the mount accommodating cavity 108 from the right. That is, as shown in Figures 9 and 10, the front and rear fitting portions 32, 32 of the second mounting member 24 are fitted into the front and rear fitting grooves 110, 110 of the mount accommodating cavity 108 of the outer bracket 16 via the fitting rubbers 54, 54, and the lower surface of the cup member 20 connected to the second mounting member 24 is overlapped with the upper surface of the lower wall of the mount accommodating cavity 108, thereby attaching the outer bracket 16 to the second mounting member 24 side of the mount body 12 from the lateral direction (left side). When the outer bracket 16 is attached to the mount body 12, the vibration-isolating base 18 and the cup member 20 are positioned relative to each other by the outer bracket 16. The fitting portion 32 is spaced apart from the inner surface of the fitting groove 110 and is press-fitted into the fitting groove 110 via a press-fit rubber 50 .

[0053] When the outer bracket 16 is attached to the mount body 12, the inner bracket 14 fixed to the first mounting member 22 has a left end, which is the mounting part to the power unit, protruding to the left of the outer bracket 16 through the window portion 115 of the outer bracket 16, as shown in Figure 4.

[0054] 3 and 4, by mounting the outer bracket 16 to the mount body 12, the vibration-isolating base 18 and the cup member 20 are closer to each other in the vertical direction than when the mount body 12 is alone. As a result, the press-fit cylindrical portion 42 of the second mounting member 24 and the upper surface of the partition insertion portion 60 of the cup member 20 are closer to each other, and the seal rubber 52 is compressed more greatly between the press-fit cylindrical portion 42 and the upper surface of the partition insertion portion 60, thereby improving the sealing performance of the seal rubber 52 between the second mounting member 24 and the cup member 20.

[0055] 4, by attaching the outer bracket 16 to the mount body 12, the inner circumferential rubber 48 covering the underside of the fixing portion 40 of the second mounting member 24 is pressed liquid-tight against the upper surface of the partition member 64, preventing a short circuit between the pressure-receiving chamber 94 and the equilibrium chamber 96 through the outer circumferential side of the partition member 64. By pressing the fixing portion 40 against the partition member 64 via the inner circumferential rubber 48, the retaining portion 92 of the flexible membrane 66 is more firmly sandwiched between the underside of the partition member 64 and the bottom wall portion 58 of the cup member 20, thereby improving the sealing performance of the retaining portion 92.

[0056] As described above, the mount body 12 alone, without the outer bracket 16 attached, is in a temporary sealed state in which the sealing performance is sufficient to prevent incompressible fluid from leaking to the outside. By attaching the outer bracket 16 to the mount body 12, the sealing performance is improved and a full sealed state is achieved in which short circuits between the pressure-receiving chamber 94 and the equilibrium chamber 96 are also prevented.

[0057] Incidentally, as the fitting portion 32 is rubber-pressed into the fitting groove 110 from right to left, the pin 34 protruding leftward from the fitting portion 32 is inserted into a pin insertion hole 114 penetrating the inner wall portion 112 of the fitting groove 110. In this embodiment, the pin 34 is inserted into the pin insertion hole 114 with a gap therebetween, but for example, the pin 34 may be inserted into the pin insertion hole 114 in a fitted state with a tightening margin therebetween.

[0058] 1 and 9, a recessed portion 120 that opens to the left side is formed around the opening edge of the pin insertion hole 114 in the outer bracket 16. The bottom surface of the recessed portion 120 is a flat surface that extends approximately perpendicular to the left-right direction, and the pin insertion hole 114 opens to the bottom surface. The tip portion of the pin 34 inserted into the pin insertion hole 114 protrudes into the recessed portion 120, so that protrusion to the left with respect to the outer bracket 16 is suppressed.

[0059] A push nut 122 serving as a connecting member is attached to the tip of the pin 34 protruding leftward from the pin insertion hole 114. As shown in Figs. 11 to 13, the push nut 122 is annular as a whole, and integrally includes a circular plate-shaped abutment portion 124 and a cylindrical mounting portion 126 protruding leftward from the inner circumferential end of the abutment portion 124. The push nut 122 is preferably made of the same material as the pin 34, and is made of a metal such as stainless steel or an aluminum alloy.

[0060] The contact portion 124 has an inner diameter larger than the outer diameter of the pin 34 and also has an outer diameter larger than the inner diameter of the left opening of the pin insertion hole 114 .

[0061] The mounting portion 126 is tapered cylindrical, and the inner diameter and the outer diameter are gradually reduced toward the left side, which is the tip side protruding from the abutting portion 124. The mounting portion 126 is provided with notches 128 at multiple locations in the circumferential direction. The notches 128 are V-shaped and expand in the circumferential direction toward the tip surface of the mounting portion 126, and reach the tip of the mounting portion 126. By providing the multiple notches 128, the mounting portion 126 is divided into multiple parts in the circumferential direction. The mounting portion 126 of this embodiment is provided with six notches 128, 128, 128, 128, 128, 128. The mounting portion 126 can be obtained, for example, by forming notches in the inner peripheral portion of a circular ring-shaped raw plate, and then pressing the inner peripheral portion of the raw plate to form the mounting portion 126.

[0062] 9 and 10, the push nut 122 is attached by fitting from the left side onto the tip portion of the pin 34 inserted into the pin insertion hole 114. The push nut 122 has an abutting portion 124 that abuts against and overlaps the left surface of the outer bracket 16 around the pin insertion hole 114, and an attachment portion 126 is attached in an externally fitted state onto the pin 34, with the tip portion of the attachment portion 126 fitted into the outer peripheral surface of the pin 34. The attachment portion 126 is divided by notches 128 into each of its circumferential portions, which are allowed to deform in the radial direction, and the pin 34 is fitted into the inner periphery of the attachment portion 126 while pushing the attachment portion 126 apart.

[0063] In this embodiment, the mounting portion 126 of the push nut 122 is tapered cylindrical, and the pin 34 is inserted into the mounting portion 126 from the opening on the right side, which is the larger diameter side of the mounting portion 126, making it easy to push the pin 34 into the inner hole of the push nut 122. Moreover, the tip of the pin 34 is chamfered so that the diameter decreases toward the tip, and the chamfered shape of the tip of the pin 34 and the tapered shape of the mounting portion 126 easily guide the pin 34 to an appropriate radial position with respect to the mounting portion 126.

[0064] The push nut 122 is limited in its rightward relative displacement with respect to the outer bracket 16 by the abutment portion 124 overlapping with the outer bracket 16. Also, the inner peripheral edge of the tip of the mounting portion 126 is pressed against the outer peripheral surface of the pin 34, and the pressing of the edge portion against the pin 34 limits the rightward relative displacement of the pin 34 with respect to the mounting portion 126. As a result, the second mounting member 24 including the pin 34 is limited in its rightward relative displacement with respect to the outer bracket 16 by the push nut 122, and the mount body 12 and the outer bracket 16 are connected to each other by the pin 34 and the push nut 122, preventing separation of the mount body 12 and the outer bracket 16 in the left-right direction. The rear wall portion 112 of the outer bracket 16 is sandwiched between the abutment portion 124 of the push nut 122 and the left end face of the fitting portion 32 in the left-right direction, so that the second mounting member 24 and the outer bracket 16 are positioned relative to each other in the left-right direction. This prevents the push nut 122 and the fitting portion 32 from coming into contact with the inner wall portion 112 of the outer bracket 16 when vibration is input in the left-right direction, thereby preventing the generation of abnormal noise.

[0065] In this way, the mount body 12 and the outer bracket 16 are positioned in the left-right direction by attaching the push nut 122 to the pin 34, so that the positioning of the mount body 12 and the outer bracket 16 can be achieved with a relatively small input compared to, for example, compressing the pin 34 in the left-right axial direction and crimping it. Also, because no large force is required to attach the push nut 122 to the pin 34, the positioning and holding force between the mount body 12 and the outer bracket 16 by pressing the rubber into the fitting groove 110 of the fitting portion 32 can be easily set to be greater than the force required to attach the push nut 122 to the pin 34. Therefore, the push nut 122 can be attached to the pin 34 without applying an external force between the mount body 12 and the outer bracket 16 to hold them in position. In other words, since the reaction force caused by pressing the rubber into the fitting groove 110 of the fitting portion 32 is easier to obtain than the force with which the push nut 122 is attached to the pin 34, it is possible to prevent the mount body 12 from shifting in the removal direction relative to the outer bracket 16 when the push nut 122 is attached to the pin 34.

[0066] If the abutment portion 124 of the push nut 122 abuts and overlaps the left face of the outer bracket 16 on the outer periphery of the pin insertion hole 114, the second mounting member 24 and the outer bracket 16 will be in an effective connected state, and therefore sufficient connecting strength can be obtained between the second mounting member 24 and the outer bracket 16 even if the inner diameter dimension of the pin insertion hole 114 is not set with high precision.

[0067] In this embodiment, a gap is provided between the pin 34 and the pin insertion hole 114, which allows the pin 34 to be easily inserted to an appropriate position in the pin insertion hole 114 and avoids damage caused by sliding contact between the outer circumferential surface of the pin 34 and the inner circumferential surface of the pin insertion hole 114. In addition, a gap is provided between the pin 34 and the pin insertion hole 114, which allows the pin 34 to be inserted into the pin insertion hole 114 even if the outer diameter dimension of the pin 34 and the inner diameter dimension of the pin insertion hole 114 are not precisely set, thereby preventing improper installation of the outer bracket 16 to the mount body 12.

[0068] A gap is provided between the pin 34 and the pin insertion hole 114, and the fitting portion 32 is assembled in a floating state against the inner surface of the fitting groove 110 via the rubber fitting 54. As a result, when vibration is input in a direction other than the left-right direction, the relative displacement between the pin 34 and the pin insertion hole 114 is limited by the vibration load being indirectly abutted between the fitting portion 32 and the fitting groove 110 via the rubber fitting 54, thereby avoiding damage to the pin 34 and abnormal noise due to contact between the pin 34 and the inner surface of the pin insertion hole 114. In short, a load in the left-right direction, which is the direction in which the second mounting member 24 and the outer bracket 16 will separate, acts on the connection portion between the second mounting member 24 and the outer bracket 16 by the push nut 122, while a load in the left-right direction, which is not a problem in terms of separation between the second mounting member 24 and the outer bracket 16, is not applied to the connection portion between the second mounting member 24 and the outer bracket 16.

[0069] Furthermore, the second mounting member 24 and outer bracket 16, which are connected by the push nut 122, are both connected to the first mounting member 22, which is the vibration source, via the main rubber elastic body 26. Therefore, input vibration is applied to the connection portion between the second mounting member 24 and the outer bracket 16 by the push nut 122 via the main rubber elastic body 26, and the acting vibration is reduced by the vibration-proofing performance of the main rubber elastic body 26. This makes it possible to prevent, for example, micro-vibrations from constantly acting on the connection portion by the push nut 122 or the input of an unintended large load, and the push nut 122 can be attached to the pin 34 with high reliability, so that the push nut 122 can stably prevent separation of the mount body 12 and the outer bracket 16.

[0070] A recessed portion 120 is formed in the portion of the outer bracket 16 where the abutment portion 124 of the push nut 122 is overlapped, and the entire abutment portion 124 is overlapped in abutting contact with the bottom surface of the recessed portion 120. The push nut 122 attached to the pin 34 is housed in the recessed portion 120, which prevents the push nut 122 from being subjected to unintended external forces and prevents the push nut 122 from shifting position relative to the pin 34, falling off, etc.

[0071] By forming the push nut 122 from the same material as the pin 34, dissimilar metal corrosion (galvanic corrosion) at the contact portion between the push nut 122 and the pin 34 can be prevented.

[0072] Furthermore, it can be easily determined whether the second mounting member 24 and the outer bracket 16 are properly connected based on whether the pin 34 has been inserted to an appropriate position in the push nut 122. Therefore, it can be determined by a simple visual inspection whether the second mounting member 24 and the outer bracket 16 are properly connected.

[0073] The engine mount 10 is used in a mounted state on a vehicle, interposed between the power unit and the vehicle body constituting a vibration transmission system, with the first mounting member 22 attached to the power unit via the inner bracket 14 and the second mounting member 24 attached to the vehicle body via the outer bracket 16. In this embodiment, the engine mount 10 is disposed on a path along which vibration is transmitted from the power unit to the vehicle body, and both the second mounting member 24 and the outer bracket 16 are disposed on the vibration transmission path, and input vibration is applied from the first mounting member 22 side through the main rubber elastic body 26. When vertical vibration is input between the first mounting member 22 and the second mounting member 24, a vibration-damping effect is exerted due to elastic deformation of the main rubber elastic body 26 interposed between the power unit and the vehicle body, and a vibration-damping effect is exerted based on the flow action of a fluid. That is, when low-frequency vibrations equivalent to engine shake are input, the relative pressure fluctuations between the pressure-receiving chamber 94 and the equilibrium chamber 96 cause fluid flow between the chambers 94, 96 through the orifice passage 98, providing a vibration-proofing effect (high damping effect) based on the fluid flow action. Also, when medium- to high-frequency vibrations such as idling vibrations or booming noise while driving are input, the hydraulic pressure transmission between the chambers 94, 96 due to the deformation of the movable membrane 84 prevents the pressure-receiving chamber 94 from becoming a high-dynamic spring due to its substantial sealing, providing a vibration-proofing effect (vibration isolation effect) based on the low-dynamic spring.

[0074] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the specific description. For example, the specific structure of the connecting member is not limited to the structure of the push nut 122 exemplified in the above embodiment. For example, instead of the cylindrical mounting portion 126, the connecting member may have an overall flat plate-like structure in which mounting protrusions protruding from the abutting portion 124 toward the inner circumference at multiple locations in the circumferential direction are provided. In this structure, the pin 34 is press-fitted into the inner circumference side of the mounting protrusions, and the mounting protrusions are fitted to the outer circumference of the pin 34, whereby the connecting member is attached to the pin 34.

[0075] The pin 34 and the push nut 122 are preferably formed from the same material, but may be formed from different materials.

[0076] In the first embodiment, a structure was exemplified in which, when the mount body 12 is in a standalone state in which the vibration-proof base 18 and the cup member 20 are connected, it is in a temporary sealed state to the extent that it is possible to prevent liquid leakage to the outside, and when the outer bracket 16 is attached to the mount body 12, it becomes in a fully sealed state when in use. However, for example, the amount of compressive deformation of the sealing rubber 52, etc. can also be set so that the fully sealed state is achieved when the mount body 12 is in a standalone state.

[0077] The second mounting member 24 and the cup member 20 are not necessarily limited to a rectangular shape with rounded corners when viewed in the vertical direction, and may be, for example, a circular or elliptical shape when viewed in the vertical direction.

[0078] In the first embodiment, the engine mount 10 is a fluid-filled type vibration damping device equipped with a fluid chamber therein, but the present invention is also applicable to, for example, a solid type vibration damping device that does not have a fluid chamber. In addition, the first member and the second member connected by the connecting member are not necessarily limited to the second mounting member 24 and the outer bracket 16 in the first embodiment. [Explanation of symbols]

[0079] 10 Engine mount (first embodiment, vibration isolation device) 12 Mount body 14 Inner bracket 16 Outer bracket (second member) 18 Anti-vibration base 20 Cup member 22 First mounting member 24 Second mounting member (first member) 26 Main body rubber elastic body (vibration-proof rubber) 28 screw holes 30 Flange-shaped part 32 Fitting part 34 pin 40 Fixing part 42 Press-fitting cylinder 44 Recess 46 Rubber layer 48 Inner rubber 50 Press-fit rubber 52 Seal rubber 54 Rubber Fitting 56 Peripheral wall section 58 Bottom wall 60 Partition insert 62 Base press-fit part 63 Through hole 64 Partitioning material 66 Flexible membrane 68 Partition member body 70 Lid fittings 72 Circumferential groove 74 Lower communication port 76 Storage Recess 78 Hollow recess 80 Central insertion part 84 Movable Membrane 86 Insertion hole 88 Upper communication port 90 Upper hole 92 Holding part 94 Pressure receiving chamber (fluid chamber) 96 Equilibrium chamber (fluid chamber) 98 Orifice Passage 104 Volts 106 First fastening hole 108 Mount Containment Void 110 Fitting groove 112 Back wall 114 Pin insertion hole 115 Window 116 Mounting piece 117 Second fastening hole 118 Open hole 120 Concave part 122 Push nut (connecting member) 124 Contact part 126 Mounting part 128 Notch

Claims

1. A vibration isolation device having a vibration isolation rubber interposed between members constituting a vibration transmission system, An anti-vibration device in which a first member and a second member are arranged on the vibration transmission path of the vibration transmission system and to which input vibration is applied via the vibration-damping rubber, and are interconnected by a pin that protrudes from the first member and is inserted into a pin insertion hole of the second member, and a connecting member that is attached to the pin.

2. The vibration-damping device described in claim 1, wherein the connecting member has an outer peripheral portion which is a ring-shaped abutment portion that is superimposed on the second member around the pin insertion hole, and an inner peripheral portion which is tapered toward the tip of the pin toward the inner circumference and is an attachment portion that is attached in an externally inserted state to the pin.

3. 3. The vibration isolation device according to claim 1, wherein the pin and the connecting member are formed from the same material.

4. 3. The vibration isolation device according to claim 1, wherein a gap is provided between the pin and an inner peripheral surface of the pin insertion hole.

5. the second member has a fitting groove; The first member has a fitting portion that is inserted into the fitting groove, a fitting rubber is provided between the fitting groove and the fitting portion, and the fitting portion is rubber-pressed into the fitting groove via the fitting rubber, 3. The vibration isolation device according to claim 1, wherein the pin is provided so as to protrude from the fitting portion in a direction in which the fitting portion is inserted into the fitting groove.

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