JP2008240843A - Fluid-sealed cylindrical vibration-isolation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid-sealed cylindrical vibration-isolation device capable of reducing the vulcanized number of components and enhancing manufacturing efficiency by reducing assembling man-hours. <P>SOLUTION: A suspension bush 10 comprises a cylindrical integrally vulcanized molding provided with a dividing slit 40 in the axial direction, in which an integrally vulcanized molding 30 is composed of an inner cylinder metal fitting 12, a metal sleeve 28, and a main body rubber elastic body 16, an orifice member 24 is composed of a plurality of arc-shaped orifice core materials 42 for covering each of pocket parts 20, an orifice forming rubber 44 is integrally vulcanized and molded around the arc-shaped orifice core materials 42, and each of the core materials 42 is integrally connected via a rubber connecting part 46. The orifice member 24 is widened by elastic deformation of the robber connecting part 46, and through the dividing slit 40, is capable of being fitted on the outer peripheral face of the metal sleeve 28 of the integrally vulcanized molding 30 from a vertical direction to the axis. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fluid-filled cylindrical vibration isolator, and in particular, has a plurality of fluid chambers in which an incompressible fluid is sealed, and is based on the flow action of the sealed fluid between the plurality of fluid chambers. The present invention relates to an improved structure of a so-called anti-vibration bush, which is a cylindrical anti-vibration device capable of obtaining a vibration effect.

  Conventionally, a shaft member that is interposed between two members constituting a vibration transmission system and is attached to one of the members to be vibration-proof connected as a kind of vibration-proof connection body that connects the two members. And an outer cylinder member that is disposed around such a shaft member at a predetermined distance outward in a direction perpendicular to the axis and is attached to the other of the two members. A plurality of fluid chambers filled with an incompressible fluid are formed in the rubber elastic body so as to be positioned in the axial direction / circumferential direction. An orifice passage that connects two predetermined fluid chambers to each other is formed, and at the time of vibration input, an incompressible fluid sealed in each of the two fluid chambers is mutually passed through the orifice passage. To be able to flow It forms a fluid-filled cylindrical vibration damping device (liquid ring vibration damping bushing) have been proposed.

  Such a fluid-filled cylindrical vibration isolator can obtain an effective anti-vibration effect based on the resonance action of an incompressible fluid that is caused to flow through the orifice passage at the time of vibration input. It is preferably used as a suspension bush such as an engine mount or body mount of an automobile or a strut bar cushion.

  By the way, in this kind of fluid-filled cylindrical vibration isolator, the input vibration of the target vibration isolator is a frequency range corresponding to the ratio of the cross-sectional area and length of the orifice passage. In order to increase the degree of freedom in designing the length and cross-sectional area of the orifice passage, and to expand the tuning range of the vibration frequency of the target vibration-proof object, the orifice passage between the outer cylinder member For example, Patent Documents 1 to 3 disclose a structure in which an orifice member to be formed is disposed in a pocket portion of a rubber elastic body that provides a fluid chamber.

  Therein, an inner cylinder member as a shaft member and a metal sleeve that is spaced apart in the radial direction are connected by a main rubber elastic body interposed therebetween, and the main rubber A plurality of pocket portions provided in the elastic body are opened to the outer peripheral surface through a window portion provided in the metal sleeve, and an orifice groove connecting between the pocket portions to be communicated among the plurality of pocket portions is provided on the outer periphery. Using an orifice member provided on the surface, it is fitted into the opening of the pocket portion, and further to the opening of the metal sleeve, and the outer cylinder member is fitted over and fixed thereon, and at least the window described above. By covering the portion and the orifice member, a plurality of fluid chambers filled with incompressible fluid are formed corresponding to the plurality of pocket portions, and the orifices corresponding to the orifice grooves are formed. In the structure of that scan path is formed, it is what is employed.

  However, in such a conventional fluid-filled cylindrical vibration isolator, the inner cylinder member, the metal sleeve, and the main rubber elastic body are configured as an integrally vulcanized molded product, and even in the orifice member, the outer peripheral surface thereof In the structure in which the orifice groove is provided on the inner peripheral surface, and the stopper portion formed of a convex portion that protrudes into the fluid chamber is provided on the inner peripheral surface thereof, the rubber material is configured as an integrally vulcanized molded product. In order to prevent leakage of incompressible fluid from the fluid chamber or orifice passage formed by fitting the orifice member, a seal rubber layer is integrally vulcanized and bonded to the inner peripheral surface of the outer cylinder fitting. The outer cylinder fitting having the seal rubber layer is fitted on the orifice member. For this reason, in order to obtain such a fluid-filled cylindrical vibration isolator, three types of integrally vulcanized molded products must be prepared, which increases the number of vulcanization points and increases manufacturing costs. In addition, since a plurality of orifice members must be prepared corresponding to the number of fluid chambers, the assembly work of the plurality of orifice members becomes troublesome and the assembly man-hours increase. Therefore, the production efficiency was not sufficient.

  For this reason, in Patent Document 4, a substantially C-shaped structure having an integral structure made of an aluminum die cast or a synthetic resin molded product in a form in which a plurality of orifice members that respectively cover a plurality of fluid chambers are connected. In addition to forming an orifice member (a restricting passage constituting member), the seal rubber layers are integrally vulcanized and molded at predetermined widths on the inner and outer peripheral surfaces at both axial ends of the substantially C-shaped orifice member, respectively. A structure has been proposed in which a seal between the fluid chamber and the seal between the orifice member and the outer cylinder member can be realized. It was something to do.

  That is, a fluid-filled cylindrical vibration isolator having a structure as disclosed in Patent Document 4 is interposed between two members constituting a vibration transmission system, and vibration transmission between these two members is attenuated or reduced. When blocking, in order to prevent an excessive displacement between the inner cylinder member and the outer cylinder member, an appropriate stopper is generally provided in the fluid chamber on the inner cylinder member side or the outer cylinder member (orifice member) side. A part will be formed. However, in the case where such a stopper portion is provided on the inner peripheral surface of the orifice member, as shown in Patent Document 4, a cylindrical block made of an inner cylinder member, a main rubber elastic body, and a metal sleeve ( In order to fit the orifice member into the integral vulcanization molded product) from the axial direction, there is a problem that the stopper portion interferes and the fitting operation cannot be performed. In addition, when the substantially C-shaped opening of the orifice member is greatly expanded to avoid interference with the stopper portion, there is a possibility that permanent deformation of the orifice member itself may be caused. Is inherent.

  Here, when such a stopper portion is provided at the bottom of the fluid chamber, it is necessary to externally arrange an appropriate stopper core metal member on the inner cylinder member as shown in Patent Document 4. Therefore, problems such as an increase in the number of parts inevitably occur, and the forming operation is troublesome. For this reason, positioning the stopper portion on the orifice member side and forming the orifice groove at the same time as the integral vulcanization molding operation increases the degree of freedom in designing the length and cross-sectional area of the orifice passage. However, in the structure as disclosed in Patent Document 4, it is not possible to sufficiently cope with the request.

No. 6-45073 JP 2001-317583 A JP 2006-22907 A Japanese Unexamined Patent Publication No. 5-65934

  Here, the present invention has been made in the background as described above, and the solution is to reduce the number of vulcanization points and reduce the assembly man-hours. An object of the present invention is to provide a fluid-filled cylindrical vibration isolator having improved efficiency.

  And in the present invention, in order to solve the above-mentioned problems or the problems grasped from the description of the entire specification and the drawings, it can be advantageously implemented in various modes as listed below. Moreover, each aspect described below can be employed in any combination. The aspects or technical features of the present invention are not limited to those described below, but can be recognized based on the description of the entire specification and the inventive concept disclosed or suggested in the drawings. It should be understood that there is.

(1) A shaft member and a metal sleeve arranged apart from each other in the direction perpendicular to the axis are connected by a main rubber elastic body interposed therebetween, and provided on the main rubber elastic body. An orifice member that opens a plurality of pocket portions to the outer peripheral surface through a window portion provided in the metal sleeve, and further covers the openings to form a plurality of fluid chambers corresponding to the plurality of pocket portions. The orifice member is fitted, and an orifice groove that connects the plurality of fluid chambers is formed on the outer surface of the orifice member, and the inner surface corresponding to the plurality of fluid chambers of the orifice member is formed on the plurality of fluid chambers. And a plurality of fluid chambers are connected to each other corresponding to the orifice groove. In a fluid-filled cylindrical vibration isolator configured to form a passing orifice passage so that incompressible fluid sealed in the plurality of fluid chambers can flow through each other through the orifice passage.
The shaft member, the metal sleeve, and the main rubber elastic body are configured as a first integral vulcanization molded product, and the orifice member has a size that can cover each of the openings of the plurality of pocket portions. A plurality of arc-shaped orifice cores and an orifice-forming rubber integrally vulcanized and molded around the orifice core, and each orifice core is arranged in the circumferential direction, and the rubber between the opposed ends Consists of a cylindrical second integrated vulcanized molded product with one split slit provided in the axial direction, which are integrally connected via a connecting portion, and the outer periphery of the second integrated vulcanized molded product On the surface, the orifice groove is formed of the orifice-forming rubber, and further, a seal rubber layer is formed which is in contact with at least the inner peripheral surface of the outer cylinder member and seals with the outer cylinder member. United The stopper portion is formed of the orifice-forming rubber on the inner peripheral surface of the molded product, and the orifice member passes through the split slit from the metal sleeve of the first integrally vulcanized molded product from the direction perpendicular to the axis. A fluid-filled cylindrical vibration isolator characterized by being configured to be fitted on an outer peripheral surface.

(2) The metal sleeve in the first integrally vulcanized molded product has rising portions that are bent radially outward at both axial end portions thereof, and the length between the rising portions of the both end portions. The fluid-filled cylindrical vibration damping device according to the aspect (1), wherein the orifice member having a width corresponding to the width is fitted on the metal sleeve.

(3) The partition rubber protruding at a predetermined height radially outward from the outer surface of the metal sleeve in the first integrally vulcanized molded product has a length extending over the entire axial length of the metal sleeve, and The fluid-filled cylindrical vibration damping device according to the aspect (1) or (2), wherein the fluid-filled cylindrical vibration damping device is provided in a width that can be fitted into the split slit of the second integrally vulcanized molded product.

(4) While the bottom surfaces of the plurality of fluid chambers each have an arc shape, the plurality of orifice cores constituting the orifice member each have an arc shape corresponding to the bottom shape of the corresponding fluid chamber. The fluid-filled cylinder according to any one of the above aspects (1) to (3), characterized in that it is an arc-shaped metal plate formed by forming a side protrusion at the stopper portion forming portion by press molding. Mold vibration isolator.

(5) On the inner and outer peripheral surfaces of at least both end portions in the axial direction of the orifice member so as to contact the inner peripheral surfaces of both end portions in the axial direction of the outer cylinder member and the outer peripheral surfaces of both end portions in the axial direction of the metal sleeve, The fluid-filled cylindrical vibration isolator according to any one of the above aspects (1) to (4), wherein the seal rubber layer is formed.

  In such a fluid-filled cylindrical vibration isolator having a structure according to the present invention, among the parts used to assemble it, the vulcanized parts include first and second integrally vulcanized molded products. This is not the case of using a vulcanized part obtained by vulcanizing and molding a seal rubber layer on the inner peripheral surface of the outer cylinder member as in the prior art. In this case, the number of vulcanization points can be effectively reduced, and the effective reduction of the vulcanization time can be advantageously achieved. is there.

  In the fluid-filled cylindrical vibration isolator according to the present invention, the orifice member that covers the openings of the plurality of pocket portions provided in the main rubber elastic body is formed of the second integral vulcanization molded product. It is composed of a single vulcanized part and is not covered with a plurality of separate arc-shaped orifice members corresponding to the plurality of pocket portions, so that a plurality of these arc-shaped orifice members are vulcanized, etc. Compared to the case of manufacturing by the above method, one of the cylindrical orifice members (second integral vulcanized molded product) according to the present invention is simply vulcanized and molded, so that the vulcanization operation is simplified. A plurality of fluid chambers can be formed by simply fitting such a cylindrical second integral vulcanized molded product as an orifice member to the first integral vulcanized molded product. Therefore, simplification of the assembling work and reduction of the assembling man-hours can be effectively achieved. Therefore, a fluid-filled cylindrical vibration isolator having high manufacturing efficiency can be obtained. It was.

  Moreover, the second integrally vulcanized molded product used in the present invention has a plurality of separate arc-shaped orifice cores each having a size capable of covering the openings of the plurality of pocket portions provided in the main rubber elastic body. Since the material is integrally connected by the rubber connecting portion formed by integral vulcanization molding of the orifice-forming rubber, the second integrally vulcanized molded product is elastically deformed in such a rubber connecting portion, The one split slit portion can be greatly expanded. For this purpose, the first perpendicular vulcanized molded product is perpendicular to the axis through the split slit portion thus expanded. As a result, the metal sleeve can be effectively attached to the outer peripheral surface of the metal sleeve.

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

  First, FIG. 1 and FIG. 2 show a suspension bush for an automobile as one embodiment of a fluid-filled cylindrical vibration isolator according to the present invention in a longitudinal sectional form and a transverse sectional form, respectively. . The suspension bush 10 was positioned coaxially at a predetermined distance outwardly in the radial direction (perpendicular to the axis) around the inner cylinder fitting 12 as a shaft member and the inner cylinder fitting 12. An outer cylinder member 14 as an outer cylinder member, and the inner cylinder member 12 and the outer cylinder member 14 are elastically provided by a main rubber elastic body 16 interposed between the two members 12 and 14. It is a structure that is connected.

  In the suspension bush 10, for example, a support shaft (not shown) fixed to the suspension arm is inserted and fixed to the inner hole 18 of the inner cylinder fitting 12. On the other hand, a cylindrical arm eye (not shown) provided on the body of the automobile is externally fitted and fixed, so that the suspension arm is interposed at the attachment site to the body. In such a mounted state, the intended vibration isolation characteristics can be exhibited mainly against vibration (load) input in the radial direction (perpendicular direction) which is the vertical direction in FIG. It has become.

  Further, in the suspension bush 10 of the present embodiment, a load (vibration) is input on both sides in the radial direction across the inner cylindrical fitting 12, particularly when the vehicle is started or accelerated, with the vehicle mounted. A pair of pocket portions 20 and 20 are formed on the main rubber elastic body 16 so as to be positioned on the lower side in FIG. 2 and on the side where the load (vibration) is input during braking (upper side in FIG. 2). Further, the openings of the pair of pocket portions 20 and 20 are covered with an orifice member 24 and further with an outer cylinder fitting 14. As a result, the pair of fluid chambers 22 and 22 filled with the incompressible fluid are positioned in the input direction of the vibration load under the mounting state on the automobile corresponding to the arrangement positions of the pair of pocket portions 20 and 20. To be formed. That is, a single orifice member 24 having a cylindrical shape as a whole is fitted so as to cover the openings of the pair of pocket portions 20, 20, thereby forming a pair of fluid chambers 22, 22. -ing The orifice member 24 and the outer cylindrical fitting 14 form an orifice passage 26 that communicates the pair of fluid chambers 22, 22.

  More specifically, as shown in FIGS. 3 to 6, the inner cylinder fitting 12 and the main rubber elastic body 16 are configured as a first integral vulcanized molded product 30 together with the metal sleeve 28. . Such a first integral vulcanized molded product 30 is, as is apparent from those drawings, disposed with a metal inner cylinder 12 having a thick, small-diameter cylindrical shape and spaced radially outward. The metal sleeve 28 is connected to the main rubber elastic body 16 by an integral vulcanization molding operation with the main rubber elastic body 16 to form an integral structure.

  In short, in the integral vulcanization molded product 30 of the inner cylindrical metal member 12, the metal sleeve 28, and the main rubber elastic body 16, the integral vulcanization molding operation opens the outer peripheral surface through the window portion 28a of the metal sleeve 28. The pair of crimped pockets 20 and 20 are formed symmetrically with the arrangement as described above. Of the pair of pocket portions 20 and 20, the side where the vibration load is input when the vehicle is started or accelerated while the suspension bush 10 is mounted on the vehicle (the lower side in FIG. 6A). In the pocket portion 20 located at the bottom, a shock absorbing rubber protrusion 38 having a predetermined height is formed integrally with the main rubber elastic body 16 on the bottom surface thereof (see FIG. 2).

  Here, as is apparent from FIGS. 7 and 8, in the metal sleeve 28, the intermediate portion in the axial direction is a small-diameter portion 28c having a long axial length, while the both end portions are short in the axial length. A pair of window portions 28a and 28a are symmetrical with respect to the axial center when the cylindrical wall portion is cut into a large rectangular shape and has a stepped cylindrical shape formed as a large-diameter portion 28d. Provided. Further, both end portions in the axial direction of the metal sleeve 28 are bent outward in the radial direction, so that rising portions 28b and 28b having a predetermined height are provided, and the rising portions 28b and 28b at both end portions are provided. As will be described later, the orifice member 24 is disposed and can be fitted on the metal sleeve 28. Therefore, here, the orifice member 24 is configured to have a width (a length in the axial direction) corresponding to the length between the rising portions 28b and 28b at both ends of the metal sleeve 28. The metal sleeve 28 having such a shape is manufactured in the same manner as in the past by a press molding operation or a punching operation on the metal cylinder.

  Further, in the integrally vulcanized molded product 30, as shown in FIGS. 4 and 6, the two window portions 28 a of the metal sleeve 28 are formed by the rubber elastic body material that wraps around from the main rubber elastic body 16. , 28a, a fitting recess 32 having a width equal to the axial length of the small-diameter portion 28c, which connects the pair of pocket portions 20 and 20 to one of the small-diameter portions 28c divided into two by the outer peripheral surface. An opening is provided in the circumferential direction. Note that two parallel seal ribs 32a and 32a are integrally formed on the bottom surface of the fitting recess 32 having a predetermined width extending in the circumferential direction so as to connect the large-diameter portions 28d and 28d at both ends of the metal sleeve 28. This provides an effective seal with the orifice member 24 when the orifice member 24 is fitted in such a fitting recess 32, as will be described later. It is like that.

  On the other hand, a partition having a predetermined height is also formed on the outer peripheral surface of the other small-diameter portion 28c separated from the metal sleeve 28 by a rubber elastic body material that wraps around from the main rubber elastic body 16 at the circumferential central portion. The wall 36 is provided as a partition rubber so as to extend in the bush axis direction with a predetermined width, thereby partitioning the pair of pocket portions 20 and 20. Further, as is clear from FIGS. 3A, 4A, 5B, and 6A, the partition wall 36 is more than the rising portions 28b at both ends of the metal sleeve 28. In addition, it is provided in a state of projecting a predetermined length radially outward, and also extends on the outer peripheral surface of the large-diameter portion 28d of the metal sleeve 28, and is equal to the axial length between the rising portions 28b and 28b. In length, they are provided integrally. In addition, on this partition wall 36, the seal rib 36a is integrally provided over the full length, so that the seal between the inner peripheral surface of the outer cylinder metal fitting 14 can be performed more reliably. It has become.

  Moreover, the orifice member 24 which forms the orifice channel | path 26 between the inner peripheral surfaces by the external fitting of the outer cylinder metal fitting 14 exhibits a cylindrical shape as a whole, as shown in FIGS. The cylindrical wall portion is configured at one place in the form of an integrally vulcanized molded product (second) that is divided in the axial direction by the split slit 40. More specifically, the orifice member 24 has a size capable of covering the opening of each pocket portion 20 and further each window portion 28a of the metal sleeve 28, as is apparent from FIG. And two separate arc-shaped orifice core members 42 and an orifice-forming rubber 44 integrally vulcanized and molded around the orifice core member 42. , Arranged in a circumferential direction so as to draw one circle, and here, the rubber connecting portions 46 formed integrally with the orifice-forming rubber 44 between the opposed one ends are integrated. It is made the structure which is connected to.

  Note that the two arc-shaped orifice core members 42 and 42 embedded in the orifice member 24, which is such an integrally vulcanized molded product, have a generally arc shape as a whole, as is apparent from FIGS. Generally, it is manufactured by press-molding a metal plate material. In such an orifice core member 42, portions having a large radius of curvature are provided on both sides in the width direction, while a central portion in the width direction is a portion having a small radius of curvature, thereby causing recesses from both sides. It has the shape. And in the center part of circular arc shape, the deeper inward protrusion part 48 which protrudes and penetrates in the pocket part 20 is formed. Further, as is apparent from FIG. 2, the lower surface shape of the inward protruding portion 48 is formed in an arc shape corresponding to the bottom surface shape of the pocket portion 20 (fluid chamber 22). Further, a long hole 50 having a predetermined length is provided in each of the arc-shaped orifice core members 42 in the arc direction at portions having large curvature radii on both sides in the width direction, and one of the long holes 50 is provided. As will be described later, the orifice passage 26 is communicated with the fluid chamber 22. As shown in FIG. 1, the arc-shaped orifice core member 42 has a width that overlaps the large-diameter portions 28d and 28d at both ends in the axial direction of the metal sleeve 28. As shown in FIG. 2, the length of each of the pockets 20 (fluid chamber 22) overlaps on both sides in the bushing circumferential direction and on the small diameter portions 28 c and 28 c of the metal sleeve 28. The length is approximately semicircular.

  As shown in FIGS. 10 to 12, the orifice member 24 is provided with a bent orifice groove 52 which gives a predetermined flow path cross-sectional area and length on the outer peripheral surface thereof. It is configured to connect to the fluid chamber 22 located below through one of the long holes 50 provided in. That is, the orifice groove 52 is provided on the outer circumferential surface of the orifice-forming rubber 44 integrally vulcanized and formed on the arc-shaped orifice core material 42 so as to extend in the circumferential direction, and FIGS. b) and FIG. 11 (a), etc., it is bent so as to be folded in the vicinity of the dividing slit 40, and is formed on the lower surface of the orifice member 24 through one long hole 50 of the orifice core member 42 at the end of the groove. It is opened and communicated with the fluid chamber 22 below.

  Further, as is apparent from FIG. 1, the cylindrical orifice member 24 has an axial length (which is substantially equal to the distance (length) between the rising portions 28b, 28b formed at both axial ends of the metal sleeve 28. It is integrally vulcanized to have a width. As a result, when fitted to the first integral vulcanization molded product 30, the orifice member 24 can be fitted to the outer peripheral surface between the rising portions 28b, 28b at both ends of the metal sleeve 28 without a gap. It is.

  Further, as is apparent from FIGS. 9, 10, 12, etc., two stopper portions 54, 54 are provided symmetrically on the inner side (inner surface side) of the orifice member 24. That is, the two stopper portions 54 and 54 are provided in the form of convex portions that project into and enter the two fluid chambers 22 and 22 (see FIG. 2), and the bottom of each fluid chamber 22 is provided. Thus, they can be arranged to face each other at a predetermined distance. Note that such a stopper portion 54 is integrally formed with a predetermined thickness on the inwardly protruding portion 48 of the orifice core member 42 by a rubber material of an orifice forming rubber 44 that wraps around the orifice core member 42. It is comprised in the form.

  In short, the orifice member 24 has an orifice groove 52 formed on the outer peripheral surface of the orifice-forming rubber 44 in the form of an integrally vulcanized molded product of the arc-shaped orifice core member 42 and the orifice-forming rubber 44. On the other hand, the stopper portion 54 is integrally formed with the orifice forming rubber 44 on the inner peripheral surface thereof. The inner peripheral surface and the outer peripheral surface are covered with the orifice-forming rubber 44 having a predetermined thickness, so that the seal rubber layer 56 is formed on the inner and outer peripheral surfaces. In addition, on the inner and outer peripheral surfaces of the orifice member 24, two seal ribs 58 and 58 are integrally provided so as to be positioned at both ends in the axial direction, and on the seal rubber layers 56 on both sides of the orifice groove 52. In addition, the seal ribs 60, 60 are integrally provided. The arrangement of the sealing ribs 58 and 60 enables the sealing of the orifice passage 26 provided by the orifice groove 52 together with the sealing of the two fluid chambers 22 and 22 to be realized more effectively.

  When assembling the suspension bush 10 as shown in FIGS. 1 and 2 using the orifice member 24 and the integral vulcanized molded product 30 as described above, first, in FIG. Thus, the orifice member 24 is fitted. That is, in such a fitting operation, the dividing slit 40 that divides the cylindrical shape of the orifice member 24 is greatly expanded and opened using the elastic deformation action of the rubber connecting portion 46, and through the opening, This is implemented by relatively inserting the integrally vulcanized molded product 30 from the direction perpendicular to the axis. By this fitting, the partition wall 36 as the partition rubber provided in the integrally vulcanized molded product 30 is fitted into the split slit 40 of the orifice member 24 (see FIG. 2). Thereafter, the outer cylinder fitting 14 is fitted onto the outer peripheral surface of the obtained assembly (fitting body) by press-fitting, so that the orifice groove 52 of the orifice member 24 becomes the outer cylinder fitting. 14 is covered with an inner peripheral surface, and therefore, a predetermined length and a flow path cross-sectional area that allows a pair of fluid chambers 22 and 22 corresponding to a pair of pocket portions 20 and 20 formed at the same time to communicate with each other. A single orifice passage 26 is formed. Then, the assembly in which the outer cylinder fitting 14 is externally fitted is further subjected to a drawing process such as an eight-way drawing and is reduced in diameter, thereby effectively fixing the outer cylinder fitting 14. Further, due to the presence of the seal rubber layer 56 and the seal ribs 58 and 60 provided on the inner and outer peripheral surfaces of the orifice member 24 and the seal ribs 32a and 36a in the integrally vulcanized molded product 30, a pair of fluid chambers 22 and 22 (pocket portions 20 and 20) and The seal around the orifice passage 26 can be sufficiently made, so that the suspension bushing 10 as shown in FIGS. 1 and 2 is completed.

  Therefore, in the structure of the suspension bush 10 as described above, there are only two types of vulcanized parts: an integral vulcanized molded product (first) 30 and an orifice member 24 (second integral vulcanized molded product). In addition, the orifice member that covers the openings of the two pockets 20 and 20 is also used in the single cylindrical orifice member 24. Since the use of a vulcanized molding of a seal rubber layer on the inner peripheral surface of the outer cylinder fitting 14 is completely unnecessary, the number of vulcanization points can be effectively reduced. Instead of assembling a plurality of orifice members, it is sufficient to use a single cylindrical orifice member 24 and to fit it into the integrally vulcanized molded product 30, so that the assembly man-hour is also effective. It will be capable of being reduced in, than Te, the suspension bushing 10 for the purpose, it became possible to obtain better production efficiency.

  Moreover, since the seal rubber layers 56 and 56 are formed on the outer peripheral surface and the inner peripheral surface of the single cylindrical orifice member 24 by the wrapping of the orifice forming rubber 44, respectively, the seal rubber layers 56 and 56 are formed. 56 is brought into close contact with the inner peripheral surface of the outer cylindrical metal member 14 and the integrally vulcanized molded product 30 (particularly, the outer peripheral surface of the metal sleeve 28), so that a seal between them can be realized well. It becomes.

  In addition, the formation of the orifice groove 52 in the orifice member 24 can be performed simultaneously by the integral vulcanization molding operation of the orifice forming rubber 44 with respect to the orifice core member 42. Thus, the vibration isolation frequency defined by the length and cross-sectional area of the orifice passage 26 provided by the orifice groove 52 can be more easily adjusted.

  Further, the orifice core member 42 embedded in the orifice member 24 is disposed separately so as to be located for each pocket portion 20 (fluid chamber 22), and is not integrated, but simply a rubber connection. Since it is only connected through the portion 46, the orifice core member 42 and therefore the orifice member 24 are not subjected to permanent deformation even if the dividing slit 40 is greatly opened. Therefore, the fitting of the orifice member 24, which is performed by inserting the integrally vulcanized molded product 30 from the direction perpendicular to the axis through the large-divided slits 40, can be realized easily and simply. It has the characteristics to obtain.

  As mentioned above, although one embodiment of the present invention has been described in detail, it is merely an example, and the present invention is interpreted in a limited manner by a specific description relating to such an embodiment. It should be understood that it is not.

  For example, in the illustrated embodiment, a pair of symmetrical pocket portions 20 (fluid chambers 22) are provided on both sides of the inner cylinder fitting 12, and such pocket portions are provided. 20 can be provided in the same structure as in the prior art, and even in the arrangement form of the orifice passage 26, the cross-sectional area and length of the flow path corresponding to the vibration frequency of the target vibration-proof object The orifice groove 52 is appropriately set by appropriately selecting the arrangement of the orifice grooves 52 so that the orifice passage can be provided.

  Further, as is well known, the inner cylinder fitting 12 and the outer cylinder fitting 14 are concentrically positioned, and are connected to each other by the main rubber elastic body 16 in an eccentricly positioned form. It is what In the case of the eccentric arrangement, when the initial load is applied, in general, the inner cylinder fitting 12 and the outer cylinder fitting 14 are eccentric so that they are concentrically positioned, and the main rubber elastic body It will be connected at 16.

  Further, as the material of the rubber elastic body constituting the main rubber elastic body 16 and the orifice forming rubber 44 and the incompressible fluid sealed in the fluid chamber 22, any known one can be used. As the compressive fluid, water, alkylene glycol, polyalkylene glycol, silicone oil or the like is employed, but generally a low-viscosity fluid of 0.1 Pa · s or less is preferably used.

  In addition, although not enumerated one by one, the present invention can be implemented in a mode to which various changes, modifications, improvements, and the like are added based on the knowledge of those skilled in the art. It goes without saying that any of the embodiments falls within the scope of the present invention without departing from the spirit of the present invention.

It is longitudinal cross-sectional explanatory drawing which shows one Embodiment of the suspension bush which has a structure according to this invention. FIG. 2 is a cross-sectional explanatory view of the suspension bush shown in FIG. 1. It is explanatory drawing of the integral vulcanization molded product used for the suspension bush shown by FIG. 1, Comprising: (a) is a front view, (b) is a right view. It is different explanatory drawing of the integrally vulcanized molded product shown by FIG. 3, Comprising: (a) is the top view, (b) is the left view. FIG. 4 is still another explanatory view of the integrally vulcanized molded product shown in FIG. 3, and (a) and (b) are a Va-Va cross-sectional explanatory view and a Vb-Vb cross-sectional explanatory view in FIG. is there. It is another explanatory drawing from which the integral vulcanization molded article shown by FIG. 3 differs, Comprising: (a) is VI-VI cross-section explanatory drawing in FIG.3 (b), (b) And (c) is this It is A section and B section expansion explanatory drawing in (a). It is explanatory drawing of the metal sleeve used in the integral vulcanization molded product shown by FIG. 3, Comprising: (a) is the front view, (b) is the left view. FIGS. 8A and 8B are different explanatory views of the metal sleeve shown in FIG. 7, respectively. FIGS. 7A and 7B are a sectional view taken along the line VIIIa-VIIIa and an explanatory view taken along the line VIIIb-VIIIb in FIG. FIG. 2 is an explanatory perspective view showing an orifice member used in the suspension bush shown in FIG. 1. It is explanatory drawing of the orifice member shown by FIG. 9, Comprising: (a) And (b) is the front view and bottom view, respectively. It is different explanatory drawing of the orifice member shown by FIG. 9, Comprising: (a) And (b) is the top view and left view, respectively. FIG. 11 is another different explanatory view of the orifice member shown in FIG. 9, wherein (a) is an XIIa-XIIa cross-sectional explanatory view in FIG. 11 (a), and (b) is an XIIb− in FIG. 10 (a). It is XIIb cross-section part expansion explanatory drawing. It is explanatory drawing of the orifice core material used for the orifice member shown by FIG. 9, Comprising: (a) And (b) is the top view and front view, respectively. It is another explanatory drawing of the orifice core material shown by FIG. 13, Comprising: (a) is the left view, (b) And (c) is each XIVb-XIVb cross section in FIG.13 (b). It is explanatory drawing and XIVc-XIVc cross-sectional explanatory drawing. It is a disassembled perspective explanatory drawing which shows the state before the assembly | attachment of the suspension bush shown by FIG.1 and FIG.2.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Suspension bush 12 Inner cylinder metal fitting 14 Outer cylinder metal fitting 16 Main body rubber elastic body 18 Inner hole 20 Pocket part 22 Fluid chamber 24 Orifice member 26 Orifice passage 28 Metal sleeve 28a Window part 28b Rising part 28c Small diameter part 28d Large diameter part 30 Integrated addition Sulfur molded product 32 Fitting recesses 32a, 36a, 58, 60 Seal rib 36 Partition wall 38 Buffer rubber protrusion 40 Divided slit 42 Orifice core material 44 Orifice forming rubber 46 Rubber connecting portion 48 Inward protruding portion 50 Long hole 52 Orifice groove 54 Stopper 56 Seal rubber layer

Claims (5)

The shaft member and the metal sleeve arranged apart from each other in the direction perpendicular to the axis are connected by a main rubber elastic body interposed therebetween, and a plurality of the sleeves provided on the main rubber elastic body are connected. The pocket portion is opened to the outer peripheral surface through a window portion provided in the metal sleeve, and the opening portion is further covered to fit an orifice member that forms a plurality of fluid chambers corresponding to the plurality of pocket portions. In addition, an orifice groove that connects the plurality of fluid chambers to each other is formed on the outer surface of the orifice member, and an inner surface corresponding to the plurality of fluid chambers of the orifice member projects into the plurality of fluid chambers. A plurality of fluid chambers corresponding to the orifice groove are connected to each other by forming a stopper portion formed of a convex portion to be inserted and fitting an outer cylinder member outside the orifice member. That forms the orifice passage, in fluid-filled cylindrical vibration damping device incompressible fluid filling the fluid chamber of said plurality of structured as can be caused to flow into one another through the orifice passage,
The shaft member, the metal sleeve, and the main rubber elastic body are configured as a first integral vulcanization molded product, and the orifice member has a size that can cover each of the openings of the plurality of pocket portions. A plurality of arc-shaped orifice cores and an orifice-forming rubber integrally vulcanized and molded around the orifice core, and each orifice core is arranged in the circumferential direction, and the rubber between the opposed ends Consists of a cylindrical second integrated vulcanized molded product with one split slit provided in the axial direction, which are integrally connected via a connecting portion, and the outer periphery of the second integrated vulcanized molded product On the surface, the orifice groove is formed of the orifice-forming rubber, and further, a seal rubber layer is formed in contact with at least the inner peripheral surface of the outer cylinder member to seal between the outer cylinder member, and the second United The stopper portion is formed of the orifice-forming rubber on the inner peripheral surface of the molded product, and the orifice member passes through the split slit from the metal sleeve of the first integrally vulcanized molded product from the direction perpendicular to the axis. A fluid-filled cylindrical vibration isolator characterized by being configured to be fitted on an outer peripheral surface.   The metal sleeve in the first integrally vulcanized molded product has rising portions that are bent radially outward at both ends in the axial direction, and corresponds to the length between the rising portions at both ends. The fluid-filled cylindrical vibration isolator according to claim 1, wherein the orifice member having a width to be fitted is fitted on the metal sleeve.   A partition rubber projecting at a predetermined height radially outward from the outer surface of the metal sleeve in the first integral vulcanization molded product has a length extending over the entire axial length of the metal sleeve, and the second The fluid-filled cylindrical vibration damping device according to claim 1 or 2, wherein the fluid-filled cylindrical vibration damping device is provided in a width that can be fitted into a split slit of the integrally vulcanized molded product.   While the bottom surfaces of the plurality of fluid chambers are each formed in an arc shape, the plurality of orifice core members constituting the orifice member each have an inward projecting portion having an arc shape corresponding to the bottom shape of the corresponding fluid chamber. The fluid-filled cylindrical vibration isolator according to any one of claims 1 to 3, wherein the fluid-filled cylindrical vibration isolator is an arc-shaped metal plate formed by pressing at a portion where the stopper portion is formed. The seal rubber layer is disposed on at least the inner and outer peripheral surfaces in the axial direction of the orifice member so as to contact the inner peripheral surfaces of both ends in the axial direction of the outer cylinder member and the outer peripheral surfaces of both ends in the axial direction of the metal sleeve. The fluid-filled cylindrical vibration isolator according to any one of claims 1 to 4, wherein each is formed.

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