Cylindrical anti-vibration device

Abstract

In a cylindrical anti-vibration device and an intermediate sleeve, stable quality is achieved by effectively performing sand blasting treatment, blowing treatment and the like on the entire intermediate sleeve. A cylindrical anti-vibration device (10) in which an inner shaft member (12) and an outer cylinder member (14) are connected by a main body rubber elastic body (16), a cylindrical intermediate sleeve (18) extending in the circumferential direction between the inner shaft member (12) and the outer cylinder member (14) in the radial direction is affixed to the main body rubber elastic body (16), and a slit (22) penetrating in the axial direction is formed in a part of the intermediate sleeve (18) in the circumferential direction. Both end portions of the slit 22 are formed as straight portions 24 extending in the axial direction, the straight portions 24 and the straight portions 24 on both sides, and the amount of direct overlap of the straight portions 24 when viewed in the axial direction is smaller than the radial thickness dimension of the intermediate sleeve 18.

Description

Technical Field

[0001] The present invention relates to a cylindrical vibration isolating device suitable for an engine bracket, a suspension bushing, etc. of an automobile, and an intermediate sleeve for the cylindrical vibration isolating device. Background Art

[0002] In the past, there are known cylindrical vibration isolating devices suitable for automobile engine mounts, suspension bushings, etc. The cylindrical vibration isolating device, for example, has a structure in which an inner shaft member (inner cylinder) and an outer cylinder member (outer cylinder) are connected by a main rubber elastic body (rubber-like elastic body), such as the bushing disclosed in Japanese Utility Model Publication No. 2-034839 (Patent Document 1).

[0003] In addition, in the cylindrical vibration isolating device, for example, a cylindrical intermediate sleeve is sometimes used for the purpose of achieving both low dynamic spring characteristics in the torsional direction and high dynamic spring characteristics in the direction perpendicular to the axis. The intermediate sleeve is arranged in a manner extending in the circumferential direction between the radial direction of the inner shaft member and the outer shaft member, and is connected to the inner shaft member and the outer shaft member through a main rubber elastic body.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Utility Model Application Laid-Open No. 2-034839 Summary of the invention

[0007] Problems to be solved by the invention

[0008] The intermediate sleeve may also be a continuous cylindrical shape throughout the entire circumference, but, for example, an intermediate sleeve (intermediate sleeve) in which a portion of the circumference is divided by a slit is shown in Patent Document 1. As a result, when the outer tube member is subjected to a diameter reduction process, the slit width becomes narrower, thereby allowing the intermediate sleeve to be deformed by diameter reduction, and pre-compression can be applied not only to the rubber between the outer tube member and the intermediate sleeve in the radial direction, but also to the rubber between the intermediate sleeve and the inner shaft member in the radial direction.

[0009] However, if a slit is formed in the intermediate sleeve to form a C-shaped cylinder as in Patent Document 1, when a plurality of intermediate sleeves are subjected to sandblasting (rough surface treatment by blowing sandblasting material) as a pretreatment for vulcanization bonding of the main rubber elastic body, other intermediate sleeves may enter the slit in the drum of the sandblasting equipment. Furthermore, it is clear that if other intermediate sleeves enter the slit, the overlapping portions of the intermediate sleeves may not be fully treated.

[0010] The problem to be solved by the present invention is to provide a cylindrical vibration isolating device of a novel structure, which can achieve stable quality by effectively performing a sandblasting treatment on the entire intermediate sleeve.

[0011] Another object is to provide an intermediate sleeve for a cylindrical vibration-proof device with a novel structure, in which other intermediate sleeves are difficult to enter into the narrow gap.

[0012] Means used to solve problems

[0013] The following describes the preferred modes for understanding the present invention, but the modes described below are illustrative modes, and can be used in combination with each other as appropriate. The multiple components described in each mode can also be identified and used as independently as possible, and can also be used in combination with any components described in other modes as appropriate. Therefore, the present invention is not limited to the modes described below, and various other modes can be realized.

[0014] The first method is a cylindrical vibration isolation device, in which an inner shaft component and an outer shaft component are connected by a main rubber elastic body, and a cylindrical intermediate sleeve extending circumferentially between the radial directions of the inner shaft component and the outer shaft component is fixed to the main rubber elastic body, wherein a slit penetrating in the axial direction is formed in a part of the circumference of the intermediate sleeve, and the two end portions of the slit are formed as straight portions extending in the axial direction, and the direct overlap amount of the straight portions on both sides when observed in the axial direction is smaller than the radial thickness dimension of the intermediate sleeve.

[0015] When the outer tube member is reduced in diameter to apply radial precompression to the main rubber elastic body, the intermediate sleeve is deformed to narrow the slit width and reduced in diameter, so that the inner peripheral portion of the main rubber elastic body than the intermediate sleeve is also effectively precompressed in the radial direction.

[0016] For example, when sandblasting is performed on a plurality of intermediate sleeves at the same time, the treatment is sometimes performed while the roller is moved while the plurality of intermediate sleeves are contained in the roller of the treatment equipment. At this time, according to the cylindrical vibration-proof device configured according to the structure of this mode, the direct overlap amount of the straight portions of the axial end portions of the slit when viewed in the axial direction is smaller than the radial thickness dimension of the intermediate sleeve. Therefore, it is possible to suppress the state where the other intermediate sleeves enter the slit by covering the straight portions on both sides relative to the slit of the intermediate sleeve, and the other intermediate sleeves are easily separated from the slit. Therefore, by the entry of the intermediate sleeve relative to the slit, the situation of local insufficiency of sandblasting treatment, etc. can be prevented, and a cylindrical vibration-proof device with the desired quality can be stably obtained. In addition, even if the other intermediate sleeves are kept in the state of entering the slit of the intermediate sleeve and do not fall off, the other intermediate sleeves will not enter the slit by covering the straight portions on both sides of the slit, and the area where the sandblasting treatment, etc. cannot be performed due to the entry of the other intermediate sleeves into the slit can be reduced.

[0017] A second aspect is the cylindrical vibration isolating device according to the first aspect, wherein the straight portions on both sides of the slit are formed at different positions in the circumferential direction of the intermediate sleeve, and the slit includes an intermediate portion connecting the straight portions on both sides in the circumferential direction.

[0018] According to the cylindrical vibration isolation device configured in accordance with the present method, the straight portions on both sides are formed at different positions on the circumferential direction of the intermediate sleeve, and these straight portions are connected through the intermediate portion to form a slit, thereby effectively allowing the diameter reduction processing of the intermediate sleeve based on the formation of the slit, and effectively preventing other intermediate sleeves from entering the slit through the straight portions on both sides.

[0019] A third aspect is the cylindrical vibration isolating device according to the second aspect, wherein an intermediate rubber is provided in the intermediate portion of the slit for connecting axially opposite side portions of the intermediate sleeve with respect to the intermediate portion.

[0020] According to the cylindrical vibration isolating device configured according to this mode, the intermediate portion extending in the circumferential direction in the middle of the axial direction of the intermediate sleeve forms the intermediate rubber when the main rubber elastic body is formed, but when the intermediate sleeve is reduced in diameter, the intermediate rubber is shear-deformed, so compared with the case of compression deformation, the elastic constant is suppressed and it is less likely to become an obstacle to the diameter reduction deformation of the intermediate sleeve. Therefore, the pre-compression of the main rubber elastic body based on the diameter reduction deformation of the intermediate sleeve can be effectively achieved, and the circumferential positions of the straight portions on both sides are greatly offset by forming the intermediate portion extending in the circumferential direction, thereby preventing the other intermediate sleeves covering the straight portions on both sides from entering the slit.

[0021] The fourth method is an intermediate sleeve for a cylindrical vibration isolation device, which has a cylindrical portion extending circumferentially between the radial directions of an inner shaft member and an outer shaft member, and the cylindrical portion is connected to the inner shaft member and the outer shaft member through a main rubber elastic body, wherein a slit penetrating along the axial direction is formed in a part of the circumference of the cylindrical portion, and the two end portions of the slit are formed as straight portions extending along the axial direction, and the direct overlap amount of the straight portions on both sides when observed in the axial direction is smaller than the radial thickness dimension of the cylindrical portion.

[0022] According to the intermediate sleeve for the cylindrical vibration isolator configured according to this embodiment, it is possible to prevent the cylindrical portions of other intermediate sleeves from entering the slits along the straight portions on both axial sides, and other intermediate sleeves entering the slits of the intermediate sleeves are easily separated from the slits.

[0023] In addition, in the fourth aspect, the following structure may be combined, that is, the straight portions on both sides of the slit are formed at different positions in the circumferential direction of the cylindrical portion, and the slit has an intermediate portion that connects the straight portions on both sides in the circumferential direction. Thus, the same effect as the second aspect can be obtained.

[0024] Effects of the Invention

[0025] According to the present invention, in the cylindrical vibration isolating device, by suppressing the other intermediate sleeves from entering the slits, the sandblasting process or the like can be effectively performed on the entire intermediate sleeve, thereby achieving stable quality.

[0026] In addition, in the intermediate sleeve for the cylindrical vibration isolator, it is possible to suppress the cylindrical portion of another intermediate sleeve from entering into the slit of the cylindrical portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a front view of the cylindrical vibration isolating device which is the first embodiment of the present invention.

[0028] Figure 2 yes Figure 1 II-II sectional view.

[0029] Figure 3 yes Figure 1 III-III sectional view.

[0030] Figure 4 yes Figure 2 IV-IV cross-sectional view.

[0031] Figure 5 yes Figure 2 VV cross-sectional view of.

[0032] Figure 6 The state before the diameter reduction process is shown. Figure 1 A front view of the cylindrical anti-vibration device shown.

[0033] Figure 7 yes Figure 6 VII-VII sectional view.

[0034] Figure 8 yes Figure 7 VIII-VIII sectional view of the invention.

[0035] Fig. 9 yes Figure 7 IX-IX sectional view.

[0036] Fig. 10A It is composed Figure 6 A top view of the middle sleeve of the cylindrical vibration isolation device is shown.

[0037] Fig. 10B It is composed Figure 1 A top view of the middle sleeve of the cylindrical vibration isolation device is shown.

[0038] Fig.11This is a front view showing a cylindrical vibration isolating device according to a second embodiment of the present invention in a state before diameter reduction processing.

[0039] Fig.12 yes Fig.11 XII-XII sectional view.

[0040] Fig.13 yes Fig.12 XIII-XIII sectional view.

[0041] Fig.14A It is composed Fig.11 A top view of the middle sleeve of the cylindrical vibration isolation device is shown.

[0042] Fig. 14B It is shown in the state after the diameter reduction process. Fig.14A A top view of the intermediate sleeve is shown.

[0043] Fig.15 This is a front view showing a cylindrical vibration isolating device according to a third embodiment of the present invention in a state before diameter reduction processing.

[0044] Fig.16 yes Fig.15 XVI-XVI sectional view.

[0045] Fig.17 yes Fig.16 XVII-XVII sectional view.

[0046] Fig.18A It is composed Fig.15 A top view of the middle sleeve of the cylindrical vibration isolation device is shown.

[0047] Fig.18B It is shown in the state after the diameter reduction process. Fig.18A A top view of the intermediate sleeve is shown.

[0048] Fig.19A This is a plan view showing an intermediate sleeve constituting a cylindrical vibration isolating device according to a fourth embodiment of the present invention in a state before diameter reduction processing.

[0049] Fig.19B It is shown in the state after the diameter reduction process. Fig.19A A top view of the intermediate sleeve is shown. DETAILED DESCRIPTION

[0050] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0051] exist Figure 1 to Figure 51 shows a cylindrical vibration isolating device 10 as a first embodiment of the present invention. The cylindrical vibration isolating device 10 has a structure in which an inner shaft member 12 and an outer cylinder member 14 are connected via a main rubber elastic body 16. In the following description, in principle, the up and down directions refer to Figure 1 The up and down directions and the left and right directions refer to Figure 1 The left and right directions in the text are Figure 2 In the left and right directions. In addition, Figure 6 to Figure 9 The figure shows the state of the outer tube member 14 in the cylindrical vibration isolation device 10 before the diameter reduction processing (an integral vulcanized molded part of the main rubber elastic body 16). Below, after explaining the various components and parts in the cylindrical vibration isolation device 10 before the diameter reduction processing, the deformation based on the diameter reduction processing of the outer tube member 14 is explained.

[0052] The inner shaft member 12 is a hard member made of metal or synthetic resin, and is formed in a substantially cylindrical shape with a thick wall and a small diameter. The inner shaft member 12 is formed in a symmetrical shape with no axial direction being limited.

[0053] The outer cylinder member 14 is a hard member formed of metal or synthetic resin, and is formed into a generally cylindrical shape that is thinner and larger in diameter than the inner shaft member 12. The axial length of the outer cylinder member 14 is shorter than that of the inner shaft member 12. The outer cylinder member 14 is formed into a symmetrical shape with no axial direction. The outer peripheral surfaces of the axial ends of the outer cylinder member 14 are formed into a tapered shape with a smaller diameter toward the axial outer side.

[0054] like Figure 6 to Figure 9 As shown, the inner shaft member 12 is inserted into the outer cylinder member 14, and a cylindrical intermediate sleeve 18 is arranged between the inner shaft member 12 and the outer cylinder member 14 in the radial direction. The intermediate sleeve 18 is a hard member formed of metal or synthetic resin, and has a cylindrical portion 20, which has a substantially cylindrical shape as a whole. The cylindrical portion 20 of the intermediate sleeve 18 of this embodiment is thinner than the outer cylinder member 14. The axial dimension of the cylindrical portion 20 is smaller than the axial dimension of the outer cylinder member 14. The diameter of the cylindrical portion 20 is larger than the diameter of the inner shaft member 12 and smaller than the diameter of the outer cylinder member 14, and the cylindrical portion 20 extends circumferentially between the radial directions of the inner shaft member 12 and the outer cylinder member 14. The cylindrical portion 20 is separated toward the outer periphery relative to the outer peripheral surface of the inner shaft member 12, and is separated toward the inner periphery relative to the inner peripheral surface of the outer cylinder member 14.

[0055] like Fig. 10A As shown, a slit 22 is formed in the cylindrical portion 20 of the intermediate sleeve 18, which penetrates the entire axial direction. The slit 22 is provided in a portion of the circumference of the intermediate sleeve 18, and the intermediate sleeve 18 is formed into a substantially C-shaped cylindrical shape in which a portion of the circumference is divided by the slit 22.

[0056] The two end portions of the slit 22 are formed as straight portions 24 and 24 extending in the axial direction. The straight portion 24 of the present embodiment extends linearly. The straight portion 24 extends in the axial direction with a substantially constant width dimension, but, for example, a draft angle may be set to facilitate removal of a mold inserted during molding of the main rubber elastic body 16 described later. In addition, a guide surface 26 of an expanded shape that is inclined toward the axial outer side and toward both sides in the circumferential direction is formed at the axial end of the straight portion 24.

[0057] The straight portions 24, 24 on both sides of the axial direction are formed at different positions in the circumferential direction of the intermediate sleeve 18, and in the present embodiment, are formed at positions separated from each other in the circumferential direction of the intermediate sleeve 18. In short, the straight portions 24, 24 of the present embodiment do not overlap each other when viewed in the axial direction, and the amount of overlap between these straight portions 24, 24 when viewed in the axial direction is less than 0. Therefore, the amount of overlap between the straight portions 24, 24 is less than the radial thickness dimension of the cylindrical portion 20 of the intermediate sleeve 18.

[0058] The straight portions 24 and the straight portions 24 are connected to each other through the middle portion 28. The middle portion 28 extends along the circumferential direction of the intermediate sleeve 18, and the end portion on one circumferential direction is connected to the straight portion 24 on the front side, and the end portion on the other circumferential direction is connected to the straight portion 24 on the rear side. The width dimension w2 of the slit 22 in the middle portion 28 may also be smaller than the width dimension w1 of the straight portions 24 and the slit 22 in the straight portions 24, but in the present embodiment, it is set to w2>w1. The width dimension w1 of the straight portions 24 and the slit 22 in the straight portions 24 is the width dimension of the straight portions 24 in the intermediate sleeve 18 before the diameter reduction, and is set according to the diameter reduction deformation amount of the intermediate sleeve 18 described later. The straight portions 24 and the straight portions 24 on both axial sides of the intermediate sleeve 18 of the present embodiment are formed about the direction perpendicular to the axis ( Fig. 10A It has a rotationally symmetrical shape of 180 degrees about an axis of symmetry L extending in a direction perpendicular to the paper surface, and the axial direction is not limited.

[0059] like Figure 6 to Figure 9As shown in the figure, a main rubber elastic body 16 is formed between the inner shaft member 12 and the outer cylinder member 14 in the radial direction where the intermediate sleeve 18 is arranged. The main rubber elastic body 16 is formed in a thick-walled substantially cylindrical shape, and the inner peripheral surface is vulcanized and bonded to the outer peripheral surface of the inner shaft member 12, and the outer peripheral surface is vulcanized and bonded to the inner peripheral surface of the outer cylinder member 14. In addition, the intermediate sleeve 18 is vulcanized and bonded in the middle of the radial direction of the main rubber elastic body 16, and the main rubber elastic body 16 is divided into the inner peripheral side and the outer peripheral side of the intermediate sleeve 18. Thus, the main rubber elastic body 16 is configured to include: an inner peripheral rubber 30 connecting the inner shaft member 12 and the cylindrical portion 20 of the intermediate sleeve 18; and an outer peripheral rubber 32 connecting the cylindrical portion 20 of the intermediate sleeve 18 and the outer cylinder member 14. The substantially entire surface of the intermediate sleeve 18 is covered by the main rubber elastic body 16, and the axial end of the cylindrical portion 20 is partially exposed from the main rubber elastic body 16 at multiple locations in the circumferential direction.

[0060] Inner grooves 34 are formed at both axial ends of the inner rubber 30, which are open toward the axial outside and extend continuously in the circumferential direction. In addition, outer grooves 36 are formed at both axial ends of the outer rubber 32, which are open toward the axial outside and extend in the circumferential direction. The bottom surfaces of the axial inner sides of the inner grooves 34 and the outer grooves 36 of the present embodiment are both substantially semicircular concave surfaces. The axial end of the cylindrical portion 20 of the intermediate sleeve 18 extends between the radial directions of the inner grooves 34 and the outer grooves 36. In addition, in the present embodiment, the axial depth dimension of the inner groove 34 is slightly smaller than that of the outer groove 36, but the depth dimensions of the inner groove 34 and the outer groove 36 may be the same as each other, or the outer groove 36 may be smaller.

[0061] The main rubber elastic body 16 is formed with spaces 38 and 38 in the portions corresponding to the straight portions 24 and 24 of the slit 22 of the intermediate sleeve 18. The space 38 is open at the axial end surface of the main rubber elastic body 16 and extends linearly in the axial direction. In the state before the outer cylinder member 14 is subjected to the diameter reduction processing, the space 38 of the present embodiment has a substantially rhombus cross-sectional shape, and is formed into a flat rhombus cross-sectional shape in which the diagonal line in the vertical direction is longer than the diagonal line in the horizontal direction. A part of the space 38 is located in the straight portion 24 of the slit 22, and extends to a position closer to the inner circumference and the outer circumference than the cylindrical portion 20 of the intermediate sleeve 18. The space 38 corresponding to the straight portion 24 on one axial side (front side) is opened at one axial end face of the main rubber elastic body 16 and extends to the middle of the axial direction of the main rubber elastic body 16, and the space 38 corresponding to the straight portion 24 on the other axial side (rear side) is opened at the other axial end face of the main rubber elastic body 16 and extends to the middle of the axial direction of the main rubber elastic body 16. In addition, the space 38 of the present embodiment does not reach the inner end (end on the middle portion 28 side) of the straight portion 24 in the axial direction, and the inner wall rubber 40 is provided on the inner side of the space 38.

[0062] The main rubber elastic body 16 includes an intermediate rubber 42 that fills the intermediate portion 28 of the slit 22 of the intermediate sleeve 18. Fig. 10A As shown, the intermediate rubber 42 extends axially in the intermediate portion 28, and both axial ends are fixed to the intermediate sleeve 18, connecting the axially opposite sides of the intermediate sleeve 18 across the intermediate portion 28 in the circumferential direction. Fig. 9 As shown, the spaces 38 and 38 are located on both sides of the intermediate rubber 42 in the circumferential direction. The intermediate rubber 42 is formed integrally and continuously with the inner rubber 30 and the outer rubber 32 in the radial direction, and the inner rubber 30 and the outer rubber 32 are integrally connected to each other through the intermediate rubber 42. In addition, when the main rubber elastic body 16 is molded, it is difficult to insert the intermediate portion 28 extending in the circumferential direction into the mold, and it is difficult to form a space such as the space 38 and the space 38 of the straight portion 24 in the intermediate portion 28, so the intermediate rubber 42 is formed to fill the intermediate portion 28.

[0063] After the main rubber elastic body 16 is vulcanized and formed, the outer cylinder member 14 is subjected to a diameter reduction process (deep drawing process) to form a Figure 1 to Figure 5 The cylindrical anti-vibration device 10 shown in the figure. The cylindrical anti-vibration device 10 applies radial pre-compression to the main rubber elastic body 16 arranged between the inner shaft member 12 and the outer cylindrical member 14 in the radial direction by reducing the diameter of the outer cylindrical member 14, thereby reducing the tensile stress caused by the heat shrinkage of the main rubber elastic body 16 after molding, thereby achieving improved durability of the main rubber elastic body 16. The method of reducing the diameter of the outer cylindrical member 14 is not particularly limited, and a diameter reduction method such as full-circumference reduction in which the outer cylindrical member 14 is pressed toward the inner circumference side by a jig pressing on the outer circumferential surface of the outer cylindrical member 14 in eight radial directions to reduce the diameter can be adopted.

[0064] When the outer tube member 14 is deformed by shrinking the diameter, the outer peripheral rubber 32 disposed between the outer tube member 14 and the intermediate sleeve 18 is compressed in the radial direction, thereby improving the durability of the outer peripheral rubber 32. In addition, the elasticity of the outer peripheral rubber 32 (the reaction force to the compression) is applied to the cylindrical portion 20 of the intermediate sleeve 18, so that the force in the shrinking direction also acts on the cylindrical portion 20. A part of the circumference of the cylindrical portion 20 is cut off by the slit 22, so that the input in the shrinking direction, such as Fig. 10BAs shown in FIG. 2 , the straight portion 24 in the slit 22 is deformed so that the width of the straight portion 24 becomes narrower. As a result, the cylindrical portion 20 of the intermediate sleeve 18 is also deformed by the diameter reduction process of the outer cylindrical member 14, and the inner peripheral rubber 30 arranged between the intermediate sleeve 18 and the inner shaft member 12 is also compressed in the radial direction, so that the durability of the inner peripheral rubber 30 can be improved. In this way, by forming the slit 22 in the intermediate sleeve 18, both the outer peripheral rubber 32 and the inner peripheral rubber 30 of the main rubber elastic body 16 are pre-compressed, which can advantageously achieve improved durability.

[0065] like Figure 1 , Figure 4 , Figure 5 As shown in FIG. 1 , by the reduction of the diameter of the intermediate sleeve 18, the spaces 38 and 38 formed in the portions corresponding to the straight portions 24 and 24 are deformed in a manner that the width dimension in the circumferential direction becomes smaller. By forming the spaces 38 and 38 in the straight portions 24 and 24, respectively, the force required for the diameter reduction deformation of the intermediate sleeve 18 becomes smaller than when the straight portions 24 and 24 are filled with rubber. This is probably because if the straight portions 24 and 24 are filled with rubber, the compression elasticity of the rubber acts as a resistance to the diameter reduction of the intermediate sleeve 18, so a larger force is required. In the present embodiment, although the spaces 38 and 38 whose widths are narrowed after the diameter reduction of the intermediate sleeve 18 remain in a state of opening at the axial end surface, for example, the inner surfaces of the walls on both sides in the circumferential direction of each space 38 may be in close contact with each other, and the spaces 38 and 38 may substantially disappear.

[0066] In addition, the intermediate rubber 42 formed in the middle portion 28 of the slit 22 is relatively displaced in the circumferential direction at both ends thereof and shear-deformed when the intermediate sleeve 18 is deformed by diameter reduction. As a result, the shear elasticity of the intermediate rubber 42 having a smaller elastic constant than the compression elasticity acts as a resistance to the diameter reduction of the intermediate sleeve 18, and thus the diameter of the intermediate sleeve 18 can be reduced with a smaller force than when the compression elasticity of the intermediate rubber 42 acts as a resistance. In addition, in the present embodiment, the inner wall rubber 40 formed integrally with the main rubber elastic body 16 is provided in the axial inner side of the space 38 and the space 38, respectively, and the inner wall rubber 40 is integrally continuous with the intermediate rubber 42 and extends from the intermediate rubber 42 to the outer side in the circumferential direction to the inner surface of the side wall of the straight portion 24. However, since one inner wall rubber 40 and the other inner wall rubber 40 are provided at positions separated from each other in the axial direction, when the intermediate sleeve 18 is reduced in diameter, the intermediate rubber 42 is not purely compressed in the circumferential direction, and a small resistance generated by the shear elasticity of the intermediate rubber 42 acts.

[0067] The cylindrical vibration isolator 10 is provided with an intermediate sleeve 18 extending in the circumferential direction between the inner shaft member 12 and the outer shaft member 14, thereby being able to set a larger ratio between the elasticity in the direction perpendicular to the shaft and the elasticity in the torsion in the circumferential direction (torsion direction). That is, the cylindrical vibration isolator 10 is provided with the intermediate sleeve 18, and thus it is easy to simultaneously achieve high dynamic elasticity in the direction perpendicular to the shaft and low dynamic elasticity in the torsion direction.

[0068] In addition, the intermediate sleeve 18 is subjected to sandblasting as a pre-treatment for improving the adhesion of the main rubber elastic body 16 before the main rubber elastic body 16 is formed. The sandblasting is a treatment for improving the adhesion strength of the main rubber elastic body 16 by peeling off and roughening the coating on the surface of the intermediate sleeve 18 by blowing sandblasting material (abrasive) onto the surface of the intermediate sleeve 18.

[0069] In the sandblasting process, sometimes a plurality of intermediate sleeves 18 are processed at once. For example, the sandblasting equipment includes a drum (processing container) capable of accommodating a plurality of intermediate sleeves 18, and the plurality of intermediate sleeves 18 are moved in the drum while rotating the drum, and the sandblasting material is sprayed onto the intermediate sleeves 18, thereby making it possible to perform sandblasting on the plurality of intermediate sleeves 18 at once.

[0070] However, for example, in an intermediate sleeve of a conventional structure having a slit extending linearly in the axial direction, if a plurality of intermediate sleeves are to be sandblasted at once as described above, other intermediate sleeves 18 are kept in a state of being inserted into the slit of the intermediate sleeve and overlapping, and the sandblasting may not be performed on the overlapping portion. As a result, the bonding strength of the main rubber elastic body 16 to the intermediate sleeve varies, or there is a risk that the main rubber elastic body 16 is partially peeled off from the intermediate sleeve.

[0071] Therefore, the intermediate sleeve 18 of the present embodiment is formed to have a structure including straight portions 24 and straight portions 24 in which the slits 22 do not directly overlap when viewed in the axial direction. Therefore, even if another intermediate sleeve 18 (cylindrical portion 20) enters the slit 22 of the intermediate sleeve 18, the other intermediate sleeve 18 does not continuously pass through the straight portions 24 and straight portions 24 of both sides and enter the slit 22, and the other intermediate sleeve 18 is easily separated from the slit 22. Therefore, by preventing the overlap caused by the other intermediate sleeve 18 entering the slit 22 of the intermediate sleeve 18 from being maintained and applying the sandblasting treatment to the entire intermediate sleeve 18, it is possible to achieve the stabilization of the adhesion of the main rubber elastic body 16 to the intermediate sleeve 18 by the stable pretreatment of the intermediate sleeve 18.

[0072] In addition, even if the entry of the other intermediate sleeve 18 relative to the slit 22 of the intermediate sleeve 18 is maintained, the other intermediate sleeve 18 can only enter the straight portion 24 of one side of the slit 22, and will not enter the straight portions 24 and straight portions 24 of both sides. Therefore, compared with the intermediate sleeve of the existing structure in which the other intermediate sleeve can enter the entire slit, the overlapping area of ​​the intermediate sleeves 18 and the intermediate sleeves 18 is reduced, and the area that cannot be sandblasted due to the overlap is narrowed, thereby reducing the deviation of the bonding strength. In addition, for easy understanding, the intermediate sleeve 18 and the other intermediate sleeve 18 are explained separately, but the above-mentioned intermediate sleeve 18 and the other intermediate sleeve 18 are substantially the same intermediate sleeves having the structure of this embodiment.

[0073] exist Figure 11 to Figure 13 , a cylindrical vibration isolating device 50 as a second embodiment of the present invention is shown in a state before the outer cylindrical member 14 is subjected to diameter reduction processing. The cylindrical vibration isolating device 50 includes an intermediate sleeve 52. In the following description, for components and parts that are substantially the same as those in the first embodiment, descriptions thereof are sometimes omitted by marking them with the same reference numerals as those in the first embodiment.

[0074] The intermediate sleeve 52 includes a cylindrical portion 54 that is generally cylindrical in shape. A portion of the cylindrical portion 54 in the circumferential direction is divided by a slit 56 in the circumferential direction. Fig.14A As shown in the figure, the slit 56 includes straight portions 24, 24 extending linearly in the axial direction from both ends of the cylindrical portion 54. The straight portions 24, 24 of this embodiment are arranged at different positions in the circumferential direction of the cylindrical portion 54 as in the first embodiment, but the spacing distance in the circumferential direction of the cylindrical portion 54 is shorter than in the first embodiment, and they are close to each other in the circumferential direction. As a result, the axial inner ends of the straight portions 24, 24 are not connected via the intermediate portion 28 extending in the circumferential direction as in the first embodiment, but are directly connected.

[0075] Spaces 38, 38 are formed in portions corresponding to the straight portions 24, 24 of the main rubber elastic body 16. Since the straight portions 24, 24 of the slit 56 are adjacent to each other in the circumferential direction, the spaces 38, 38 formed at positions corresponding to the straight portions 24 are adjacent to each other in the circumferential direction.

[0076] A thin film-like intermediate rubber 58 is formed between adjacent portions on the inner side of the space 38 and the space 38. The intermediate rubber 58 is a rubber film formed in the gap between the molds for forming the space 38 and the space 38 when the main rubber elastic body 16 is molded, and is formed integrally with the main rubber elastic body 16. The intermediate rubber 58 of this embodiment is formed so as to connect the inner wall rubbers 40 and the inner wall rubbers 40 formed on the inner side of the space 38 and the space 38 to each other.

[0077] Moreover, if Fig. 14B As shown, by performing the diameter reduction process on the outer cylinder member 14 after the vulcanization molding of the main rubber elastic body 16, the intermediate sleeve 52 is deformed and reduced in diameter in such a way that the straight portion 24 of the slit 56 and the circumferential width dimension of the straight portion 24 become smaller. When the intermediate sleeve 52 is reduced in diameter, the axial ends of the intermediate rubber 58 are relatively displaced in the circumferential direction to generate shear deformation. The intermediate rubber 58 of this embodiment formed in a thin film may also be broken along with the deformation.

[0078] The same effects as those of the first embodiment can be obtained by the cylindrical vibration isolating device 50 having such an intermediate sleeve 52. In addition, in the cylindrical vibration isolating device 50 of the present embodiment, the circumferential thickness dimension of the intermediate rubber 58 is small, so when the diameter of the intermediate sleeve 52 is reduced, the force resisting the diameter reduction based on the elasticity of the intermediate rubber 58 is further reduced, and the diameter reduction deformation of the intermediate sleeve 52 can be effectively made with a smaller force.

[0079] exist Figure 15 to Figure 17 , a cylindrical vibration isolating device 60 as a third embodiment of the present invention is shown in a state before the outer cylindrical member 14 is subjected to diameter reduction processing. The cylindrical vibration isolating device 60 includes an intermediate sleeve 62.

[0080] The intermediate sleeve 62 includes a cylindrical portion 64 that is generally cylindrical in shape. A portion of the cylindrical portion 64 in the circumferential direction is divided by a slit 66 in the circumferential direction. Fig.18A As shown in FIG. 1 , the slit 66 includes straight portions 24 and 24 extending linearly in the axial direction from both ends of the cylindrical portion 64. The straight portions 24 and 24 of the present embodiment are formed at different positions in the circumferential direction of the cylindrical portion 64, but have a portion directly overlapping when viewed in the axial direction, and the slit 66 extends linearly in the axial direction through the overlapping portion. The circumferential width (overlap amount) d of the overlapping portion of the straight portions 24 and 24 when viewed in the axial direction is smaller than the radial thickness dimension of the cylindrical portion 64 of the intermediate sleeve 62. Therefore, even if the cylindrical portion 64 of the other intermediate sleeve 62 enters from the straight portion 24 side of one side relative to the slit 66 of the intermediate sleeve 62, the other intermediate sleeve 62 will not pass over the connecting portion of the straight portions 24 and 24 and enter the straight portion 24 of the other side.

[0081] An intermediate rubber 68 is formed at the connection between the straight portions 24 and 24. The intermediate rubber 68 of this embodiment is located at the inner side of each of the straight portions 24 and 24, and connects the inner surfaces of the walls on both sides of the slit 66 in the circumferential direction to each other at the connection between the straight portions 24 and 24.

[0082] Moreover, if Fig.18BAs shown, by performing the diameter reduction process on the outer cylinder member 14 after the vulcanization molding of the main rubber elastic body 16, the intermediate sleeve 62 is deformed and reduced in diameter in such a way that the circumferential width dimension of the straight portion 24 of the slit 66 becomes smaller. When the intermediate sleeve 62 is reduced in diameter, the intermediate rubber 68 is compressed and deformed in the circumferential direction. However, since the axial length dimension of the intermediate rubber 68 is sufficiently small, the resistance due to the compressive elasticity of the intermediate rubber 68 is unlikely to become a problem when the intermediate sleeve 62 is reduced in diameter.

[0083] The same effect as that of the first embodiment can be obtained by the cylindrical vibration isolating device 60 having such an intermediate sleeve 62. As shown in this embodiment, the straight portions 24 and 24 of the slit 66 do not need to be arranged at positions separated in the circumferential direction, and the same effect can be obtained as long as the overlap amount is specified in a manner that can restrict the other intermediate sleeves 62 from entering the slit even if they partially overlap when viewed in the axial direction.

[0084] Fig. 19 shows an intermediate sleeve 70 constituting a cylindrical vibration isolator as a fourth embodiment of the present invention. In this embodiment, only the intermediate sleeve 70 and an intermediate rubber 82 described later are shown, but the other parts of the cylindrical vibration isolator not shown can adopt the same structure as the first embodiment.

[0085] The intermediate sleeve 70 includes a cylindrical portion 72 that is generally cylindrical in shape. A portion of the cylindrical portion 72 in the circumferential direction is divided by a slit 74 in the circumferential direction. Fig.19A As shown, the slit 74 includes straight portions 24 and 24 extending linearly in the axial direction from both axial ends of the cylindrical portion 72. The straight portions 24 and 24 of the present embodiment are formed at the same positions in the circumferential direction of the intermediate sleeve 70.

[0086] The slit 74 includes an intermediate portion 76 that connects the straight portions 24 and 24 to each other. The intermediate portion 76 includes an axial extension portion 78 that extends axially at a position different from the straight portions 24 and 24 in the circumferential direction, and a circumferential extension portion 80 that connects the inner end portions of the straight portions 24 and 24 to both ends of the axial extension portion 78. Fig.19A As shown, the intermediate portion 76 is in an inverted U shape in a plan view, and both ends are connected to the straight portions 24 on either side.

[0087] An intermediate rubber 82 is fixed to the intermediate portion 76 of the slit 74 . The intermediate rubber 82 is formed integrally with the main rubber elastic body 16 (not shown), and is provided over the entire intermediate portion 76 .

[0088] Moreover, if Fig.19BAs shown, by performing the diameter reduction processing on the outer cylinder member 14 after the vulcanization molding of the main rubber elastic body 16, the intermediate sleeve 70 is deformed and reduced in diameter in such a way that the straight portion 24 of the slit 74 and the circumferential width dimension of the straight portion 24 become smaller. When the intermediate sleeve 70 is reduced in diameter, the intermediate rubber 82 is compressed in the circumferential direction, but if the axial length dimension of the intermediate rubber 82 is sufficiently small, it is possible to prevent the resistance generated by the compression elasticity of the intermediate rubber 82 from becoming a problem during the diameter reduction of the intermediate sleeve 70. In addition, the axial length of the axial extension portion 78 can also be set to be sufficiently small, for example, the width dimension of the axial extension portion 78 and / or the width dimension of the circumferential extension portion 80 can also be set to be larger than the width dimension of the straight portion 24. Furthermore, the overall shape of the intermediate portion 76 is not limited to the U-shape in the front view as shown in the example, and can also be an arc shape or the like.

[0089] The same effect as the first embodiment can be obtained by using the cylindrical vibration isolating device having such an intermediate sleeve 70. As in the slit 74 shown in this embodiment, the straight portions 24 and 24 do not need to be arranged at mutually different positions in the circumferential direction. As long as the intermediate portion 76 is used to restrict the entry of other intermediate sleeves 70, the same effect as the above embodiment can be achieved.

[0090] The embodiments of the present invention are described in detail above, but the present invention is not limited to the specific description. For example, the straight portion 24 of the slit 22 may also have a varying width in the axial direction. Specifically, for example, the straight portion 24 may also gradually widen in width toward both ends of the axial direction.

[0091] The intermediate portion 28 connecting the straight portions 24 and the straight portions 24 in the slit 22 may extend in the circumferential direction while being inclined in the axial direction, and the inclination angle may vary in the circumferential direction.

[0092] The opening shape of the space 38 formed in the main rubber elastic body 16 is not limited to the substantially rhombus shape shown in the above embodiment, and may be substantially circular including an elliptical shape, substantially rectangular, or the like.

[0093] The intermediate rubber formed in the slit is not essential, and the intermediate rubber may not be formed. In addition, when the intermediate rubber is formed, the intermediate rubber is preferably arranged in a manner of shear deformation when the intermediate sleeve is deformed by shrinking diameter, but as shown in the third embodiment and the fourth embodiment, there may be a compressed portion when the intermediate sleeve is deformed by shrinking diameter, or the entirety may be compressed.

[0094] In the above-mentioned embodiment, sandblasting is exemplified as a treatment that can cause other intermediate sleeves to enter the slit relative to the intermediate sleeve, but the entry of other intermediate sleeves into the slit relative to the intermediate sleeve can also be suppressed when the intermediate sleeve is subjected to treatment other than sandblasting, such as a blowing treatment of an adhesive or the like.

[0095] Description of Reference Numerals

[0096] 10: Cylindrical anti-vibration device (first embodiment);

[0097] 12: Inner shaft component;

[0098] 14: outer cylinder member;

[0099] 16: Main rubber elastic body;

[0100] 18: middle sleeve;

[0101] 20: Tubular part;

[0102] 22: Slit;

[0103] 24: straight part;

[0104] 26: guide surface;

[0105] 28: middle part;

[0106] 30: Inner rubber;

[0107] 32: peripheral rubber;

[0108] 34: inner groove;

[0109] 36: peripheral groove;

[0110] 38: Space;

[0111] 40: inner wall rubber;

[0112] 42: middle rubber;

[0113] 50: Cylindrical anti-vibration device (second embodiment);

[0114] 52: middle sleeve;

[0115] 54: Tubular part;

[0116] 56: Slit;

[0117] 58: middle rubber;

[0118] 60: Cylindrical anti-vibration device (third embodiment);

[0119] 62: middle sleeve;

[0120] 64: Tubular part;

[0121] 66: Slit;

[0122] 68: middle rubber;

[0123] 70: intermediate sleeve (fourth embodiment);

[0124] 72: Tubular part;

[0125] 74: Slit;

[0126] 76: middle part;

[0127] 78: axial extension portion;

[0128] 80: circumferential extension;

[0129] 82: Middle rubber.

Claims

1. A cylindrical vibration isolating device, wherein an inner shaft member and an outer shaft member are connected via a main rubber elastic body, and a cylindrical intermediate sleeve extending in the circumferential direction between the radial direction of the inner shaft member and the outer shaft member is fixed to the main rubber elastic body, wherein: A slit penetrating in the axial direction is formed in a portion of the circumference of the intermediate sleeve. Both end portions of the slit are formed as straight portions extending in the axial direction. The direct overlap of the straight portions on both sides when viewed axially is smaller than the radial thickness dimension of the intermediate sleeve.

2. The cylindrical vibration isolating device according to claim 1, wherein: The straight portions on both sides of the slit are formed at different positions in the circumferential direction of the intermediate sleeve. The slit includes a middle portion connecting the straight portions on both sides to each other in the circumferential direction.

3. The cylindrical vibration isolating device according to claim 2, wherein: An intermediate rubber is provided in the intermediate portion of the slit to connect the intermediate sleeve to both sides of the intermediate portion in the axial direction.

4. An intermediate sleeve for a cylindrical vibration isolating device, comprising a cylindrical portion extending circumferentially between the radial direction of an inner shaft member and an outer cylinder member, the cylindrical portion being connected to the inner shaft member and the outer cylinder member through a main rubber elastic body, wherein: A slit penetrating in the axial direction is formed in a part of the circumference of the cylindrical portion. Both end portions of the slit are formed as straight portions extending in the axial direction. The direct overlap amount of the straight portions on both sides when viewed in the axial direction is smaller than the radial thickness dimension of the cylindrical portion.

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