Liquid-filled vibration isolation device and method for manufacturing a liquid-filled vibration isolation device

Abstract

To provide a liquid-sealed type vibration isolator to which a diaphragm can be properly assembled, and a manufacturing method of the liquid-sealed type vibration isolator.SOLUTION: A diaphragm 15 comprises a contact part 15a in contact with a plurality of wall parts 23 of an annular member 16 at an internal peripheral side. Even if the annular member 16 is positionally displaced in a radial direction up until the member is brought into contact with an internal peripheral face of a second attachment tool 12 (seal wall part 14) which is not contracted in a diameter yet, an inclination of the annular member 16 with respect to a partitioning body 20 can be regulated by the contact of the contact part 15a with the wall parts 23. By contracting a diameter of the second attachment tool 12 in a state in which the inclination is regulated, the diaphragm 15 (annular member 16) can be fixed to an internal peripheral side of the second attachment tool 12 at a proper angle. That is, even in the case where the partitioning body 20 comprises the plate-shaped wall parts 23 which are aligned in a circumferential direction, and a thickness of the annular member 16 in a radial direction is formed thin, the diaphragm 15 can be properly assembled.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a liquid-filled vibration damping device and a method of manufacturing a liquid-filled vibration damping device, and in particular to a liquid-filled vibration damping device capable of properly assembling a diaphragm and a method of manufacturing the liquid-filled vibration damping device.

Background Art

[0002] As a vibration damping device that supports a vibration source such as an engine on a vehicle body, for example, the liquid-filled vibration damping device disclosed in Patent Document 1 is known. This liquid-filled vibration damping device includes a first member (first mounting member 1) attached to the vibration source side, a cylindrical second member (second mounting member 2) attached to the vehicle body side, and a vibration damping base body (rubber base body 3) connecting the first member and the second member. A liquid chamber (liquid sealing chamber 5) is formed between the diaphragm attached to the second member and the vibration damping base body, and the liquid chamber is partitioned into a first liquid chamber and a second liquid chamber by a partition body (partition member 6).

[0003] An annular annular member is fixed (bonded) to the outer edge of the diaphragm. Although the radial thickness of the annular member described in Patent Document 1 is larger than the axial thickness thereof, in order to improve the durability of the diaphragm, it is preferable to form the annular member to have a small thickness in the radial direction and ensure a large inner diameter of the annular member. This is because increasing the inner diameter of the annular member can correspondingly increase the free length of the diaphragm.

Prior Art Literature

Patent Literature

[0004]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0005] However, increasing the inner diameter of the annular member can make it difficult to properly assemble the diaphragm. This problem will be explained with reference to Figures 4 and 5. Figure 4 is a cross-sectional view of a reference example of a liquid-filled vibration isolation device 210, and Figure 5 is a perspective view of the partition body 20. In Figure 4, the opening of the second mounting fixture 12 (second member) is shown facing upwards before the diameter reduction process. Furthermore, the liquid-filled vibration isolation device 210 shown in Figure 4 has the same configuration as the liquid-filled vibration isolation device 10 (shown in Figure 1), which will be described later, except that the configuration of the diaphragm 215 is different.

[0006] As shown in Figure 4, when assembling the diaphragm 215 to the liquid-filled vibration isolation device 210, the annular member 16 is superimposed on the partition body 20 set on the inner circumference of the cylindrical second mounting fixture 12, and the second mounting fixture 12 is subjected to a diameter reduction process. At this time, if the axis of the annular member 16 and the axis of the partition body 20 coincide (are concentric), that is, if the annular member 16 is correctly superimposed on the partition body 20, tilting of the annular member 16 relative to the partition body 20 is unlikely to occur.

[0007] However, if the annular member 16 is radially misaligned to a position beyond the outer edge of the partition body 20, the annular member 16 will tilt so as to fit between the second mounting fixture 12 and the partition body 20. Such tilting of the annular member 16 is more likely to occur when multiple wall portions 23 are formed on the outer edge of the partition body 20, as shown in Figure 5. It should be noted that the structure in which an annular member 16 with a larger inner diameter is superimposed on a partition body 20 having multiple wall portions 23 (the configuration shown in Figure 4) was not known at the time of filing this application.

[0008] As shown in Figure 5, the partition body 20 comprises a cylindrical tube portion 21, a flange-like projection 22 extending radially outward from the axial end of the tube portion 21 (the lower end in Figure 5), and rib-like wall portions 23 protruding from the projection 22 and the tube portion 21. Each of these portions 21 to 23 is integrally formed using metal or synthetic resin.

[0009] In the example shown in Figure 5, twelve wall sections 23 are arranged along the circumferential direction, and these multiple wall sections 23 are formed in a plate shape with their thickness direction oriented in the circumferential direction. Because these multiple wall sections 23 arranged in the circumferential direction are formed on the outer edge of the partition body 20, when the annular member 16 is placed on top of the partition body 20 (wall sections 23), the number of contact points between the partition body 20 and the annular member 16 (points that restrict the inclination of the annular member 16) is reduced.

[0010] Therefore, as shown in Figure 4, if the annular member 16 is radially misaligned to a position beyond the wall portion 23, the annular member 16 is more likely to tilt relative to the partition body 20. Furthermore, if the inner diameter of the annular member 16 is increased (the thickness in the radial direction is reduced), even if the radial misalignment of the annular member 16 is slight, the annular member 16 will extend beyond the wall portion 23 and fit between the second mounting fixture 12 and the partition body 20, making the annular member 16 more likely to tilt. If the second mounting fixture 12 is reduced in diameter while the annular member 16 is tilted, there is a problem in that the diaphragm 215 cannot be properly assembled.

[0011] The present invention was made to solve the above-mentioned problems and aims to provide a liquid-filled vibration isolation device and a method for manufacturing a liquid-filled vibration isolation device that can properly assemble a diaphragm. [Means for solving the problem]

[0012] To achieve this objective, the liquid-filled vibration isolation device of the present invention comprises a first member and a cylindrical second member; a vibration isolation base made of a rubber-like elastic material connecting the first member and the second member; a diaphragm forming a liquid chamber between itself and the vibration isolation base in which liquid is sealed; an annular member fixed to the outer edge of the diaphragm and held on the inner circumference side of the second member; and a partition body dividing the liquid chamber into a first liquid chamber on the vibration isolation base side and a second liquid chamber on the diaphragm side. The partition body is formed in a plate shape extending in the radial direction and has a plurality of wall portions arranged in the circumferential direction on the outer edge of the partition body; the annular member is formed with a radial thickness thinner than its axial thickness; and the diaphragm has a contact portion that restricts the inclination of the annular member with respect to the partition body by contacting the wall portions on the inner circumference side of the annular member.

[0013] The present invention provides a method for manufacturing a liquid-filled vibration damping device comprising: a first member and a cylindrical second member; a vibration damping base made of a rubber-like elastic material connecting the first member and the second member; a diaphragm forming a liquid chamber between itself and the vibration damping base in which liquid is sealed; an annular member fixed to the outer edge of the diaphragm and held on the inner circumference side of the second member; and a partition body dividing the liquid chamber into a first liquid chamber on the vibration damping base side and a second liquid chamber on the diaphragm side, wherein the partition body is formed in a plate shape extending in the radial direction and has a plurality of wall portions arranged in the circumferential direction on the outer edge of the partition body, and the ring A method for manufacturing a liquid-filled vibration isolation device, wherein the annular member is formed with a radial thickness thinner than its axial thickness, and the diaphragm has a contact portion formed on the inner circumference side of the annular member, comprising: a first step of stacking the annular member on a plurality of wall portions; and a second step of reducing the diameter of the second member after the first step, wherein in the first step, if the annular member is radially displaced until it contacts the inner circumference surface of the second member before the diameter reduction, the inclination of the annular member with respect to the partition is restricted by bringing the contact portion into contact with the axial end face of the wall portion. [Effects of the Invention]

[0014] The liquid-filled vibration damping device described in claim 1 provides the following effects: Since the diaphragm has a contact portion that contacts the wall portion on the inner circumference side of the annular member, even if the annular member is radially misaligned before the second member is reduced in diameter, the inclination of the annular member with respect to the partition body can be restricted by the contact between the wall portion and the contact portion. In other words, even if the partition body has a plurality of plate-shaped wall portions arranged in the circumferential direction and the annular member is formed with a thin radial thickness, the diaphragm can be properly assembled.

[0015] The liquid-filled vibration isolation device described in claim 2 provides the following effects in addition to those of the liquid-filled vibration isolation device described in claim 1: Since the contact portion is formed continuously in the circumferential direction, the contact portion can be brought into contact with multiple wall portions without having to position the annular member in the circumferential direction. Therefore, the workability of the diaphragm assembly work is improved.

[0016] The liquid-filled vibration isolation device described in claim 3 provides the following effects in addition to those of the liquid-filled vibration isolation device described in claim 1. Since the contact portion is a projection that protrudes toward the partition body side from the axial end face of the annular member, the contact portion of the rubber-like elastic material can be brought into contact with the wall when the annular member is placed on top of the partition body. This makes it less likely for the annular member to shift radially (slip) relative to the partition body, which has the effect of allowing the diaphragm to be properly assembled.

[0017] The liquid-filled vibration damping device according to claim 4 provides the following effects in addition to the effects of the liquid-filled vibration damping device according to claim 3. The diaphragm is formed between the annular member and the contact portion and has a groove-shaped recess that is continuous in the circumferential direction. This allows the inner circumference of the annular member to be sealed by the projection of the mold for forming the recess of the diaphragm when the molded body consisting of the diaphragm and the annular member is vulcanized. Therefore, it has the effect of suppressing the intrusion of rubber material between the axial end face of the annular member and the mold.

[0018] According to the method for manufacturing a liquid-filled vibration damping device according to claim 5, the following effects are obtained. The method includes a first step of overlapping an annular member on a plurality of wall portions, and a second step of reducing the diameter of the second member after the first step. In the first step, even if the annular member is displaced in the radial direction until it comes into contact with the inner circumferential surface of the second member before diameter reduction, the contact portion is configured to come into contact with the axial end surface of the wall portion, so the inclination of the annular member relative to the partition body can be restricted by such contact. That is, even when the partition body includes a plurality of plate-shaped wall portions arranged in the circumferential direction and the annular member is formed to have a small radial thickness, there is an effect that the diaphragm can be properly assembled. [Brief Description of the Drawings]

[0019] [Figure 1] It is a cross-sectional view of a liquid-filled vibration damping device according to one embodiment of the present invention. [Figure 2] (a) is a cross-sectional view of the liquid-filled vibration damping device showing a state before diameter reduction processing of a second attachment, and (b) is a cross-sectional view of the liquid-filled vibration damping device showing a state where the annular member is displaced in the radial direction from the state of FIG. 2(a). [Figure 3] (a) is a partially enlarged cross-sectional view of a diaphragm and an annular member at part IIIa in FIG. 2(b), and (b) is a partially enlarged cross-sectional view of a lower mold and an upper mold for vulcanization molding of the diaphragm. [Figure 4] It is a cross-sectional view of a liquid-filled vibration damping device of a reference example. [Figure 5] It is a perspective view of a partition body. [Mode for Carrying Out the Invention]

[0020] Hereinafter, preferred embodiments will be described with reference to the accompanying drawings. FIG. 1 is a cross-sectional view of a liquid-filled vibration damping device 10 according to one embodiment of the present invention. Note that FIG. 1 illustrates a state before the liquid-filled vibration damping device 10 supports an engine (that is, a state before the weight of the engine is applied), which is a stationary state where no vibration is input to the liquid-filled vibration damping device 10. Further, the cross-sectional view of the liquid-filled vibration damping device 10 in FIG. 1 is an axial cross-sectional view including the axis C of the cylindrical second attachment 12.

[0021] In the following description, one side of the second fitting 12 in the axial direction (the upper side in FIG. 1) is referred to as the upper side of the liquid-filled vibration isolator 10, and the other side in the same direction (the lower side in FIG. 1) is referred to as the lower side. However, the vertical orientation of the liquid-filled vibration isolator 10 does not necessarily match the vertical orientation of the vehicle to which the liquid-filled vibration isolator 10 is attached.

[0022] The liquid-filled vibration isolator 10 is an engine mount that elastically supports an automobile engine. The liquid-filled vibration isolator 10 includes a first fitting 11 attached to an engine (not shown) side which is a vibration source, a cylindrical second fitting 12 attached to a vehicle body (not shown) on the support side, and a vibration isolating base body 13 connecting the first fitting 11 and the second fitting 12.

[0023] The first fitting 11 is a boss fitting disposed on the axis C of the second fitting 12 so as to be positioned above the second fitting 12, and is formed of a metal such as steel or aluminum alloy. A bolt hole is formed in an upper end surface of the first fitting 11, and the first fitting 11 is attached to the engine side by a bolt (not shown) fitted into the bolt hole.

[0024] The second fitting 12 is formed into a cylindrical shape using a metal such as steel. The second fitting 12 includes a large-diameter portion 12a on an upper end side, a reduced-diameter portion 12b continuous to a lower end of the large-diameter portion 12a and having inner and outer diameters gradually decreasing downward, and a small-diameter portion 12c continuous to a lower end of the reduced-diameter portion 12b and having smaller inner and outer diameters than the large-diameter portion 12a. The second fitting 12 is attached to the vehicle body side by fitting the large-diameter portion 12a into a cylindrical bracket provided on the vehicle body side.

[0025] The vibration isolating base body 13 is formed into a substantially umbrella shape using an elastic body such as rubber or thermoplastic elastomer. The vibration isolating base body 13 is vulcanized and bonded to a lower portion of the first fitting 11 and inner peripheral surfaces of the large-diameter portion 12a and the reduced-diameter portion 12b, respectively, to connect these components. A rubber film-like seal wall portion 14 is continuous to a lower end portion of the vibration isolating base body 13, and the seal wall portion 14 covers the entire inner peripheral surface of the small-diameter portion 12c. This seal wall portion 14 is a part of the second fitting 12.

[0026] A diaphragm 15 is attached to the second mounting fixture 12 via an annular member 16 to close the opening at the lower end of the small-diameter portion 12c. The diaphragm 15 is a membrane made of an elastic material such as rubber. The annular member 16 is formed in an annular shape using a metal such as steel, and the outer edge of the diaphragm 15 is vulcanized and bonded around the entire circumference of the inner surface of the annular member 16.

[0027] A liquid chamber is formed by a sealed space partitioned by the vibration-isolating base 13, the second mounting fixture 12, and the diaphragm 15. An antifreeze liquid (not shown), such as ethylene glycol, is sealed in the liquid chamber. The liquid chamber is divided by a partition 20 into a first liquid chamber 17, in which the vibration-isolating base 13 forms part of the chamber wall, and a second liquid chamber 18, in which the diaphragm 15 forms part of the chamber wall.

[0028] The partition body 20 shown in Figure 1 has the same configuration as the partition body 20 shown in Figure 5, and comprises a cylindrical portion 21, an overhanging portion 22, and a wall portion 23. The upper surface of the overhanging portion 22 contacts the step 13a of the vibration-damping base 13, which protrudes radially inward in a stepped manner from the upper end of the sealing wall portion 14, and the outer surface of the partition body 20 is pressed against the entire circumference of the inner surface of the second mounting fixture 12 via the sealing wall portion 14.

[0029] The axial edge 23a (lower edge) of the wall portion 23 is formed in a straight line extending radially from the lower edge of the cylindrical portion 21, and the outer peripheral edge 23b of the wall portion 23 is formed in a straight line extending axially from the outer peripheral edge of the protruding portion 22. In other words, the wall portion 23 is formed in a rectangular plate shape that connects the outer peripheral surface of the cylindrical portion 21 and the lower surface of the protruding portion 22.

[0030] Multiple wall sections 23 are arranged along the circumferential direction (in this embodiment, at 12 locations). The partition body 20 has alternating areas in the circumferential direction where the distance between the multiple wall sections 23 is relatively narrow and areas where the distance is wide (see Figure 5). In other words, in this embodiment, the multiple wall sections 23 are arranged at unequal intervals in the circumferential direction, but a configuration in which the wall sections 23 are arranged at equal intervals in the circumferential direction is also possible.

[0031] The partition body 20 comprises a disc-shaped partition portion 24 connected to the inner circumferential surface of the cylindrical portion 21, and an upper rib portion 25 and a lower rib portion 26 formed on the upper and lower surfaces of the partition portion 24, with each of these portions 24 to 26 being integrally formed with the cylindrical portion 21.

[0032] A circular opening 24a is formed in the center of the partition 24. The upper rib portion 25 is formed in the shape of a wall that slopes downward from the upper end of the inner circumferential surface of the cylindrical portion 21 toward the opening 24a, and the lower rib portion 26 is formed in the shape of a wall that slopes upward from the lower end of the inner circumferential surface of the cylindrical portion 21 toward the opening 24a.

[0033] Multiple upper rib portions 25 and lower rib portions 26 are arranged in the circumferential direction (in this embodiment, eight are arranged radially), and each of these multiple upper rib portions 25 and lower rib portions 26 is positioned to overlap vertically.

[0034] The partition body 20 and the diaphragm 15 (annular member 16) are held on the inner circumference side of the seal wall portion 14 by reducing the diameter of the second mounting fixture 12. This diameter reduction process will be explained with reference to Figure 2. Figure 2(a) is a cross-sectional view of the liquid-filled vibration isolation device 10 showing the state before the second mounting fixture 12 is reduced in diameter, and Figure 2(b) is a cross-sectional view of the liquid-filled vibration isolation device 10 showing the state in which the annular member 16 has shifted radially from the state in Figure 2(a). Note that in Figure 2, the opening of the second mounting fixture 12 is shown facing upward before the diameter reduction process.

[0035] As shown in Figure 2, when assembling the diaphragm 15 into the liquid-filled vibration isolation device 10, first, the partition body 20 is set on the inner circumference side of the second mounting fixture 12 before its diameter is reduced, and the annular member 16 is placed on the axial end face (upper surface in Figure 2) of the partition body 20 (first step). With the annular member 16 placed on the partition body 20, the diameter of the second mounting fixture 12 is reduced (second step), thereby assembling the diaphragm 15 to the inner circumference side of the second mounting fixture 12 (see Figure 1).

[0036] In a state before diameter reduction processing is performed on the second attachment 12, the inner diameter D1 of the second attachment 12 (seal wall portion 14) is larger than the outer diameter D2 of the annular member 16 and the outer diameter D3 of the partition body 20. The outer diameter D3 of the partition body 20 refers to the diameter of a circle that includes the outer edges E of the plurality of wall portions 23 when an intersection point between an end edge 23a and an outer peripheral edge 23b of the wall portion 23 is defined as the outer edge E of the wall portion 23.

[0037] In the state before diameter reduction of the second attachment 12, when the annular member 16 is arranged at a fixed position where the axis center of the partition body 20 coincides with the axis center of the annular member 16 (hereinafter simply referred to as "fixed position"), a gap G having a size of "(D1-D2) / 2" is formed between the outer peripheral surface of the annular member 16 and the inner peripheral surface of the second attachment 12 (seal wall portion 14). Therefore, when the annular member 16 is displaced in the radial direction from the fixed position until it comes into contact with the second attachment 12 (seal wall portion 14), the annular member 16 is displaced by a maximum distance of "(D1-D2) / 2". In the present embodiment, even when such displacement of the annular member 16 occurs, the contact portion 15a of the diaphragm 15 is configured to come into contact with the end edge 23a of the wall portion 23.

[0038] The contact portion 15a is a projection that protrudes toward the partition body 20 side relative to the annular member 16. The contact portion 15a is formed in an annular shape continuous in the circumferential direction, and let D4 be the diameter of a circle including the apex P of the contact portion 15a (the inner edge at the contact portion with the wall portion 23). When the annular member 16 is arranged at the fixed position, the distance from the apex P of the contact portion 15a to the outer edge E of the wall portion 23 is represented by "(D3-D4) / 2", and this distance is larger than the gap G between the second attachment 12 (seal wall portion 14) before diameter reduction and the annular member 16 (satisfies "D1-D2<D3-D4").

[0039] As a result, even if the annular member 16 is displaced radially until it contacts the inner circumferential surface of the second mounting fixture 12 (seal wall portion 14) before diameter reduction (see Figure 2(b)), the contact portion 15a can maintain contact with the edge 23a of the wall portion 23. The inclination of the annular member 16 relative to the partition body 20 can be restricted by the contact between the contact portion 15a and the edge 23a of the wall portion 23. By reducing the diameter of the second mounting fixture 12 while this inclination is restricted, the diaphragm 15 (annular member 16) can be fixed at an appropriate angle on the inner circumferential side of the second mounting fixture 12. In other words, even if the partition body 20 is equipped with a plurality of plate-shaped wall portions 23 arranged in the circumferential direction, and the radial thickness of the annular member 16 is formed to be thin, as in this embodiment, the diaphragm 15 can be properly assembled.

[0040] Thus, when the inclination of the annular member 16 relative to the partition 20 is restricted by the contact portion 15a, it is also possible to adopt a configuration in which the contact portion 15a is formed intermittently in the circumferential direction. However, in such a configuration, it is necessary to position the annular member 16 in the circumferential direction so that the contact portion 15a contacts multiple wall portions 23.

[0041] In contrast, in this embodiment, since the contact portion 15a is formed in a continuous annular shape in the circumferential direction, the contact portion 15a can be brought into contact with multiple wall portions 23 without having to position the annular member 16 in the circumferential direction. Therefore, the workability of assembling the diaphragm 15 is improved.

[0042] Furthermore, as long as the diaphragm 15 can be properly assembled, the configuration may not involve the contact portion 15a protruding from the axial end face of the annular member 16 (the lower face in Figure 2). However, in such a configuration, the metal annular member 16, rather than the rubber contact portion 15a, will be in contact with the partition 20, making the annular member 16 more prone to radial displacement (for example, metal-to-metal contact is prone to slipping).

[0043] In contrast, the contact portion 15a in this embodiment is a projection that protrudes toward the partition body 20 (wall portion 23) side than the axial end face of the annular member 16. Therefore, when the annular member 16 is placed on top of the partition body 20, the contact portion 15a, rather than the annular member 16, can be brought into contact with the wall portion 23. By bringing the rubber contact portion 15a into contact with the wall portion 23 (partition body 20), the annular member 16 becomes less likely to shift radially relative to the partition body 20 (less likely to slip), so the diaphragm 15 can be properly assembled.

[0044] Next, with reference to Figure 3, a method for molding a molded body consisting of a diaphragm 15 and an annular member 16 will be described. Figure 3(a) is a partially enlarged cross-sectional view of the diaphragm 15 and annular member 16 in part IIIa of Figure 2(b), and Figure 3(b) is a partially enlarged cross-sectional view of the lower mold 30 and upper mold 40 for vulcanizing the diaphragm 15. In Figure 3(a), the contact portion 15a1 of the modified example is shown by a dashed line.

[0045] As shown in Figure 3, the molded body consisting of the diaphragm 15 and the annular member 16 is formed by a vulcanizing mold using a lower mold 30 and an upper mold 40. The lower mold 30 is a mold for forming the outer shape of one axial side (the lower side in Figure 3(a)) of the diaphragm 15. The lower mold 30 and the upper mold 40 have first grooves 31 and 41 formed therein for clamping the annular member 16, and these first grooves 31 and 41 are annular recesses that face each other vertically when the mold is clamped. A second groove 32 is formed on the inner circumference side of the first groove 31 of the lower mold 30 (the left side in Figure 3(b)). The second groove 32 is an annular recess for forming the contact portion 15a of the diaphragm 15.

[0046] Projections 33 are formed between each groove 31, 32 of the lower mold 30, projecting upward. The projections 33 are formed in a convex shape (rising from the inner edge of the first groove 31 and the outer edge of the second groove 32) that constitute the inner wall of the first groove 31 and the outer wall of the second groove 32, and these projections 33 seal the inner circumference of the annular member 16 when the mold is clamped. By sealing the inner circumference of the annular member 16 with the projections 33, it is possible to prevent the rubber material injected into the cavity C between the lower mold 30 and the upper mold 40 from seeping between the axial end face of the annular member 16 and the first groove 31.

[0047] The projection 33 seals the inner circumference of the annular member 16, forming a groove-shaped recess 15b that is continuous in the circumferential direction between the annular member 16 and the contact portion 15a of the diaphragm 15. In other words, by forming such a recess 15b between the contact portion 15a and the annular member 16, the inner circumference of the annular member 16 can be sealed by the projection 33 of the lower mold 30 as described above. Therefore, it is possible to prevent rubber material from entering between the annular member 16 and the first groove 31 of the lower mold 30. A recess 15c is also formed on the outer edge portion of the other axial side of the diaphragm 15 (the upper side in Figure 3(a)). The recess 15c is an annular recess that is continuous with the inner surface of the annular member 16, and is formed in a shape symmetrical to the recess 15b with respect to the plane perpendicular to the axis of the annular member 16 as the plane of symmetry.

[0048] Here, as shown in Figure 1, after the annular member 16 is superimposed on the partition body 20 and the second mounting fixture 12 is processed to reduce its diameter, the axial end of the second mounting fixture 12 is crimped to the inner circumference to form a crimped portion 12d. During this crimping process, the annular member 16 is pushed towards the partition body 20 by the crimped portion 12d (seal wall portion 14) of the second mounting fixture 12. In this case, as in this embodiment, if the contact portion 15a protrudes from the axial end face of the annular member 16 towards the partition body 20 (wall portion 23), the contact portion 15a is pressed towards the wall portion 23 when the crimped portion 12d is crimped.

[0049] Therefore, for example, as shown by the dashed line in Figure 3(a), if the amount of protrusion of the contact portion 15a1 from the axial end face of the annular member 16 is large and the recess 15b is omitted, when the contact portion 15a1 is pressed against the wall portion 23 during the crimping process described above, the stress due to the deformation of the contact portion 15a1 tends to concentrate at the joint between the diaphragm 15 and the annular member 16.

[0050] In contrast, in this embodiment, the amount of protrusion of the contact portion 15a from the axial end face of the annular member 16 is small (for example, 10% or less of the axial dimension of the annular member 16), and a circumferentially continuous recess 15b is formed between the contact portion 15a and the annular member 16. This reduces the amount of deformation of the contact portion 15a when it is pressed against the wall portion 23 during the crimping process described above, and allows a portion of this deformation to be absorbed by the recess 15b. This suppresses the concentration of stress at the joint between the diaphragm 15 and the annular member 16, thereby improving the durability of the diaphragm 15.

[0051] Furthermore, in a cross-section including the axis of the annular member 16, the contact portion 15a is formed in a convex arc shape toward the wall portion 23, and an arc-shaped recess 15b is connected to the outer edge of this arc-shaped contact portion 15a. By connecting the uneven portion consisting of the contact portion 15a and the recess 15b with a smooth curved surface, it is possible to suppress the concentration of stress in a part of the uneven portion when the contact portion 15a is pressed against the wall portion 23. Thus, the durability of the diaphragm 15 can be improved.

[0052] Although the present invention has been described above based on the above embodiments, it can be easily inferred that the present invention is not limited in any way to the above embodiments, and that various modifications and improvements are possible without departing from the spirit of the present invention.

[0053] In the above embodiment, the case in which the contact portion 15a is formed continuously in the circumferential direction has been described, but it is not necessarily limited to this. For example, the contact portion 15a may be formed intermittently in the circumferential direction. The configuration in which the contact portion 15a is formed intermittently in the circumferential direction involves forming recesses between a plurality of contact portions 15a arranged in the circumferential direction. In such a configuration, the contact portion 15a may be in contact with the wall portion 23, or the wall portion 23 may be fitted into the recesses formed between each contact portion 15a (formed at positions corresponding to the plurality of wall portions 23). By fitting the wall portion 23 into the recesses between each contact portion 15a, the diaphragm 15 can be positioned in the circumferential direction.

[0054] In the above embodiment, the case in which the contact portion 15a is a projection that protrudes from the partition body 20 (wall portion 23) side of the annular member 16 has been described, but it is not necessarily limited to this. For example, the axial end face of the annular member 16 (the end face on the partition body 20 side) and the contact portion 15a may be formed flush. Also, as long as the diaphragm 15 can be properly assembled (to the extent that excessive tilting of the annular member 16 can be restricted), the contact portion 15a may not protrude from the axial end face of the annular member 16 (the contact portion 15a may be formed to be slightly lower than the axial end face of the annular member 16).

[0055] In the above embodiment, a case was described in which a circumferentially continuous recess 15b is formed between the contact portion 15a and the annular member 16, but this is not necessarily the only case. For example, the recess 15b may be formed intermittently in the circumferential direction, or a contact portion 15a1 with a shape that fills the recess 15b may be formed on the diaphragm 15 (omitting the recess 15b), as shown by the dashed line in Figure 3(a). [Explanation of Symbols]

[0056] 10. Liquid-filled vibration isolation device 11. First mounting bracket (first component) 12. Second mounting bracket (second component) 13 Vibration Isolation Base 15 diaphragm 15a Contact part 15b Recess 16 Annular member 17 1st liquid chamber 18 2nd liquid chamber 20 partitions 23 Wall

Claims

1. The device comprises a first member and a cylindrical second member, a vibration-damping base made of a rubber-like elastic material connecting the first member and the second member, a diaphragm forming a liquid chamber between it and the vibration-damping base in which liquid is sealed, an annular member fixed to the outer edge of the diaphragm and held on the inner circumference side of the second member, and a partition body dividing the liquid chamber into a first liquid chamber on the vibration-damping base side and a second liquid chamber on the diaphragm side. The partition body is formed in a plate shape extending in the radial direction, and has a plurality of wall portions arranged in the circumferential direction on the outer edge of the partition body. The annular member is formed with a thickness in the radial direction that is thinner than its thickness in the axial direction. The liquid-filled vibration isolation device is characterized in that the diaphragm has a contact portion that restricts the inclination of the annular member relative to the partition by contacting the wall portion on the inner circumference side of the annular member.

2. The liquid-filled vibration isolation device according to claim 1, characterized in that the contact portion is formed continuously in the circumferential direction.

3. The liquid-filled vibration isolation device according to claim 1, characterized in that the contact portion is a projection that protrudes toward the partition body side from the axial end face of the annular member.

4. The liquid-filled vibration damping device according to claim 3, characterized in that the diaphragm has a groove-shaped recess formed between the annular member and the contact portion and is continuous in the circumferential direction.

5. A method for manufacturing a liquid-filled vibration damping device comprising: a first member and a cylindrical second member; a vibration-damping base made of a rubber-like elastic material connecting the first member and the second member; a diaphragm forming a liquid chamber between itself and the vibration-damping base in which liquid is sealed; an annular member fixed to the outer edge of the diaphragm and held on the inner circumference side of the second member; and a partition body dividing the liquid chamber into a first liquid chamber on the vibration-damping base side and a second liquid chamber on the diaphragm side, wherein the partition body is formed in a plate shape extending in the radial direction and has a plurality of wall portions arranged in the circumferential direction on the outer edge of the partition body; the annular member is formed with a radial thickness thinner than its axial thickness; and the diaphragm has a contact portion formed on the inner circumference side of the annular member, A first step involves stacking the annular members on multiple wall portions, The process includes a second step of reducing the diameter of the second member after the first step, A method for manufacturing a liquid-filled vibration damping device, characterized in that, in the first step, if the annular member is displaced radially until it contacts the inner circumferential surface of the second member before the diameter reduction, the inclination of the annular member with respect to the partition is restricted by bringing the contact portion into contact with the axial end surface of the wall portion.

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