Cylindrical anti-vibration device

Abstract

The invention provides a cylindrical anti-vibration device with a novel structure, which can stably obtain the falling resistance of a resin outer member relative to a sleeve member. A cylindrical anti-vibration device (10) in which an inner shaft member (12) and a cylindrical resin outer member (14) are connected by a main body rubber elastic body (16), the resin outer member (14) is provided with a retaining protrusion (24) protruding on the outer peripheral surface, a window (44) into which the retaining protrusion (24) is inserted is formed in a cylindrical sleeve member (40) into which the resin outer member (14) is fitted, and a sealing member (30) is provided around the retaining protrusion (24). A gap (56) is provided between the retaining projection and the window portion on the tip side in the direction in which the resin outer member is fitted into the sleeve member and on both sides in the circumferential direction, and the end surface of the retaining projection on the base end side in the direction in which the resin outer member is fitted into the sleeve member is formed as a locking surface (32) inclined toward the tip side in the direction in which the resin outer member is fitted into the sleeve member. The sleeve member is locked in the axial direction with respect to the locking surface.

Description

Technical Field

[0001] The present invention relates to a cylindrical anti-vibration device used as, for example, a subframe bracket of an automobile. Background Art

[0002] Conventionally, cylindrical vibration isolation devices are known for use in subframe brackets of automobiles, etc. For example, as disclosed in Japanese Patent Application Laid-Open No. 2010-078101 (Patent Document 1), a cylindrical vibration isolation device has a structure in which an inner shaft member and an outer cylindrical member are connected by a main rubber elastic body.

[0003] Prior art literature Patent Literature Patent Document 1: Japanese Patent Application Laid-Open No. 2010-078101 Summary of the Invention Problems to be solved by the invention However, the outer cylindrical member has conventionally been made of metal such as iron or aluminum alloy. Patent Document 1 proposes making the outer cylindrical member of synthetic resin for the purpose of reducing the weight of the cylindrical anti-vibration device.

[0004] However, when an outer tube component (resin outer component) made of synthetic resin is used, for example, when it is embedded in a sleeve component of a sub-frame, the shape and size are easily changed over time (fatigue) due to the continuous action of the fitting force toward the inner circumference. Due to fatigue, the resistance to falling off is reduced, and there is a risk that the resin outer component will fall off from the sleeve component.

[0005] Patent Document 1 also discloses that a circular anti-slip protrusion formed on the outer circumference of a resin outer member is locked with a corresponding circular window in a sleeve member, thereby ensuring resistance to slipping. In Patent Document 1, the anti-slip protrusion is locked with the opening circumference of the window portion when the edge of the opening circumference of the circular window portion is sunken into the peripheral wall surface of the circular anti-slip protrusion formed into a tapered shape.

[0006] However, in the structure of patent document 1, the center points of the anti-slip protrusion and the window portion need to be positioned with relatively high precision. If the relative position of the anti-slip protrusion and the window portion is offset due to dimensional errors, etc., they will be lifted up in a point contact state in the circumferential direction of the circle, resulting in gaps in other parts, and there is a risk that the intended anti-slip effect cannot be effectively exerted.

[0007] In particular, the anti-slip protrusion is provided at the outer peripheral end of the cylindrical anti-vibration device. Therefore, even if there is only a slight offset in the center angle between the cylindrical anti-vibration device and the sleeve member, a large circumferential offset is likely to occur between the anti-slip protrusion and the window portion, and there is a problem that the circumferential offset between the anti-slip protrusion and the window portion is easily problematic. On this basis, the anti-slip protrusion and the window portion that are locked to each other are provided in pairs at intervals in the circumferential direction. Therefore, any dimensional error in each pair of anti-slip protrusions and windows affects both parties, making it more difficult to accurately align the center points of the pair of anti-slip protrusions and windows for locking.

[0008] The present invention solves the problem of providing a cylindrical vibration isolating device having a new structure that can stably obtain resistance to the resin outer member from falling off of the collar member.

[0009] Means used to solve problems The following describes preferred embodiments for understanding the present invention. However, each embodiment described below is merely exemplary and can be appropriately combined with one another. Multiple components described in each embodiment can also be independently identified and employed to the greatest extent possible. Furthermore, the present invention can be appropriately combined with any components described in other embodiments. Therefore, the present invention is not limited to the embodiments described below, and various other embodiments are possible.

[0010] The first method is a cylindrical vibration isolation device, which is a cylindrical vibration isolation device in which an inner shaft member is inserted into a cylindrical resin outer member, and these inner shaft members and the resin outer member are connected by a main rubber elastic body, wherein the resin outer member is provided with an anti-slip convex portion protruding on the outer peripheral surface, and a window portion for inserting the anti-slip convex portion is formed in the cylindrical sleeve member for the resin outer member to be embedded, and a gap is provided around the anti-slip convex portion, on the front end side and both sides of the circumference in the embedding direction of the resin outer member into the sleeve member, between the anti-slip convex portion and the window portion, and the end face of the anti-slip convex portion on the base end side of the embedding direction of the resin outer member into the sleeve member is formed as a stopping surface inclined toward the outer periphery and toward the front end side of the embedding direction, and the sleeve member is axially locked relative to the stopping surface.

[0011] According to the cylindrical vibration isolator structured in accordance with this embodiment, a gap is provided around the anti-slip convex portion, on the front end side in the embedding direction of the resin outer member into the sleeve member and on both sides in the circumferential direction, between the anti-slip convex portion and the window portion. Thus, the gap allows for relative positional deviation between the anti-slip convex portion and the window portion.

[0012] Furthermore, the end surface of the resin outer member in the anti-slip convex portion, in the insertion direction of the sleeve member, is formed as a locking surface that is inclined toward the outer periphery and toward the front end of the insertion direction, and the sleeve member is axially locked relative to the locking surface. In this way, the portion of the peripheral wall surface of the anti-slip convex portion that is locked with the opening peripheral edge of the window portion is formed as a locking surface having a certain degree of width in the axial direction. Therefore, even if the relative position of the anti-slip convex portion and the window portion shifts in the axial direction, the anti-slip convex portion and the opening peripheral edge of the window portion are stably locked, effectively exerting the intended resistance to falling off, and preventing the resin outer member and the sleeve member from loosening, etc.

[0013] In the second embodiment, based on the cylindrical vibration isolation device described in the first embodiment, the end face of the front end side of the embedding direction of the resin outer component in the anti-slip protrusion into the sleeve component is formed as a guide surface inclined toward the outer periphery and toward the base end side of the embedding direction, and the inclination angle of the guide surface relative to the embedding direction is formed to be smaller than the inclination angle of the locking surface.

[0014] According to the cylindrical vibration isolation device configured in accordance with this embodiment, when the sleeve member passes over the anti-slip protrusion, the sleeve member is guided by the guide surface, thereby reducing the force required to insert the resin outer member into the sleeve member. Furthermore, the guide surface is formed at a smaller inclination angle relative to the insertion direction than the retaining surface, thereby further preventing the sleeve member from getting caught on the guide surface, thereby reducing the force required for the sleeve member to pass over the anti-slip protrusion.

[0015] A third aspect is the cylindrical vibration isolating device according to the first or second aspect, wherein the anti-fall-off projections are provided on both sides in a radial direction.

[0016] According to the cylindrical vibration isolation device formed in accordance with this embodiment, the resistance to falling off exerted by the locking of the anti-falling protrusions on both radial sides with the windows of the sleeve member acts evenly in the circumferential direction, thereby preventing, for example, the resin outer member from tilting relative to the sleeve member. In this embodiment, as long as the anti-falling protrusions are provided on both radial sides, there may be multiple anti-falling protrusions. For example, if one anti-falling protrusion is provided on each radial side, the force required for embedding can be suppressed, and the resistance to falling off can be evenly achieved in the circumferential direction. In addition, the sleeve member is provided with windows in the portions corresponding to the anti-falling protrusions on both radial sides.

[0017] A fourth aspect is the cylindrical vibration isolating device according to any one of the first to third aspects, wherein the gap is formed so as to be larger between the anti-slip protrusion and the window in the circumferential direction than in the axial direction.

[0018] According to the cylindrical vibration-isolating device formed into a structure according to this method, the anti-slip protrusion protruding from the outer circumferential surface of the resin outer member is separated from the central axis of the resin outer member. As a result, even when the resin outer member and the sleeve member are slightly offset in the circumferential direction, there is a hidden danger of a large circumferential offset relative to the window portion. On the other hand, the relative position of the anti-slip protrusion and the window portion in the axial direction can be set with high precision, and the offset can be reduced compared to the relative position in the circumferential direction. Therefore, by forming the circumferential gap between the anti-slip protrusion and the window portion to be larger than the axial gap, the size of the window portion can be reduced while fully allowing the circumferential relative orientation offset of the resin outer member and the sleeve member, which is relatively easy to increase.

[0019] A fifth aspect is the cylindrical vibration isolation device according to any one of the first to fourth aspects, wherein the locking surface of the anti-slip protrusion and the opening peripheral edge of the window portion in the sleeve member locked with the locking surface both extend in a direction perpendicular to the axial direction.

[0020] According to the cylindrical vibration isolation device formed in accordance with the present method, the locking surfaces of the anti-slip protrusions and the peripheral edge of the opening of the window portion of the sleeve member, which are locked to each other, are axially orthogonal to the direction in which the resin outer member falls off from the sleeve member, thereby effectively obtaining resistance to falling off by locking the locking surfaces of the anti-slip protrusions and the peripheral edge of the opening of the window portion.

[0021] The sixth aspect is the cylindrical vibration isolation device according to the fifth aspect, wherein the anti-slip protrusion and the window portion include a pair of first pairs of sides extending in a direction perpendicular to the axial direction and a pair of second pairs of sides extending in the axial direction when viewed in the protruding direction of the anti-slip protrusion.

[0022] According to the cylindrical anti-vibration device formed in accordance with this embodiment, the circumferential clearance is substantially constant throughout the entire axial direction, thereby allowing for circumferential positional deviations between the anti-slip protrusion and the window portion with good spatial efficiency. Similarly, the axial clearance is substantially constant throughout the entire circumferential direction, thereby allowing for axial positional deviations between the anti-slip protrusion and the window portion with good spatial efficiency.

[0023] In addition, the end of the anti-slip protrusion on the front end side is formed as a first pair of sides perpendicular to the axial direction, so that when the sleeve member passes over the anti-slip protrusion, it is difficult for the resin outer member and the sleeve member to tilt relative to each other, and it can be stably embedded.

[0024] Effects of the Invention According to the present invention, in the cylindrical anti-vibration device, it is possible to stably obtain the resistance of the resin outer member to falling off from the collar member. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1It is a front view showing a state where the sub-frame bracket according to the first embodiment of the present invention is assembled to the collar member.

[0026] Figure 2 yes Figure 1 II-II sectional view.

[0027] Figure 3 yes Figure 1 Sectional view III-III.

[0028] Description of Reference Numerals 10: Sub-frame bracket (first embodiment of cylindrical anti-vibration device); 12: Inner shaft component; 14: Resin outer member; 16: Main rubber elastic body; 18: Tubular part; 20: flange-shaped portion; 22: cone surface; 24: Anti-detachment convex part; 26: first convex side opposite edges (first pair of edges of the anti-slip convex portion); 28: second convex side opposite edge portion (second opposite edge portion of the anti-slip convex portion); 30: guiding surface; 32: stop surface; 34: front face; 36: first limiting portion; 38: second limiting portion; 40: casing component; 42: mounting hole; 44: Window; 46: first window side opposite edges (first pair of edges of the window portion); 48: second window side opposite edges (second opposite edges of the window); 50: edge; 52: axial clearance; 54: circumferential clearance; 56: gap; L0: axial length dimension of the cylindrical portion of the resin outer member; L1: axial length of the anti-slip convex part; L2: axial length of the guide surface; L3: axial length of the stop surface; L4: axial length of the window; L5: axial length of the sleeve component; W1: circumferential width of the anti-slip convex portion; W2: circumferential width of the window; H: the protruding height of the anti-slip convex part; T: thickness dimension of the cylindrical portion of the resin outer member; α: inclination angle of the guiding surface; β: the inclination angle of the stop surface; D1: Width of axial clearance; D2: Width dimension of circumferential gap. DETAILED DESCRIPTION

[0029] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0030] exist Figures 1 to 3 In the figure, as a first embodiment of a cylindrical anti-vibration device according to the present invention, a sub-frame bracket 10 for an automobile is shown in a state where it is assembled to a sleeve member 40 described later. The sub-frame bracket 10 has a structure in which an inner shaft member 12 is inserted through a cylindrical resin outer member 14, and these inner shaft member 12 and the resin outer member 14 are connected by a main rubber elastic body 16. In principle, in the following description, the vertical direction refers to the axial direction. Figure 1 The up-down direction and the front-back direction refer to Figure 2 The left and right directions in Figure 1 Left and right direction in .

[0031] The inner shaft member 12 is formed into a thick, small-diameter, substantially cylindrical shape, extending straight with a substantially constant cross-sectional shape. The inner shaft member 12 is formed of a metal such as iron, aluminum alloy, or fiber-reinforced synthetic resin, and is a hard member.

[0032] The resin outer member 14 includes a substantially cylindrical tubular portion 18. The tubular portion 18 is thinner and larger in diameter than the inner shaft member 12. The resin outer member 14 is made of a synthetic resin, such as polyamide, polyoxymethylene, polybutylene terephthalate, polyethylene, or polytetrafluoroethylene. The resin outer member 14 can be formed from a single synthetic resin material such as those described above. Preferably, the resin outer member 14 is formed from a fiber-reinforced synthetic resin reinforced with glass fiber, carbon fiber, aramid fiber, or the like.

[0033] The lower end of the resin outer member 14 is integrally formed with a protruding annular flange 20. The outer peripheral surface of the upper end of the resin outer member 14 is formed into a tapered surface 22 with a smaller diameter toward the upper end. The inner peripheral surface of the upper end of the resin outer member 14 protrudes inward compared to the inner peripheral surface of the remaining portion, and the tapered surface 22 forms a thinner wall toward the upper end.

[0034] The resin outer member 14 is formed with a pair of anti-fall-off projections 24, 24 projecting from the outer peripheral surface of the cylindrical portion 18. Figure 1As shown, the anti-slip convex portion 24 is formed to be approximately quadrilateral when viewed in the front-back direction, and is formed to be approximately rectangular in this embodiment. Figure 2 、 Figure 3 As shown, the anti-slip protrusions 24 are provided on both sides in the radial direction (front-back direction). When viewed in the front-back direction, the anti-slip protrusions 24 have first convex side opposite sides 26, 26 at both ends in the axial direction, forming a pair of first side opposite sides extending circumferentially on a plane orthogonal to the axial direction, and second convex side opposite sides 28, 28 at both ends in the circumferential direction, forming a second side opposite sides extending parallel to the axial direction.

[0035] like Figure 2 As shown, the height dimension of the protrusion of the anti-slip convex portion 24 from the outer peripheral surface of the cylindrical portion 18 varies in the axial direction. In more detail, the upper portion of the protruding front end surface of the anti-slip convex portion 24 is formed as a guide surface 30 that is inclined upward and toward the inner periphery, and the lower portion is formed as a stop surface 32 that is inclined upward and toward the outer periphery. In addition, a front end surface 34 that extends non-inclined relative to the axial direction is provided between the guide surface 30 and the stop surface 32 in the protruding front end surface of the anti-slip convex portion 24. The stop surface 32 constitutes the first convex side opposite edge portion 26 on the lower side, and extends circumferentially on a plane orthogonal to the axial direction.

[0036] The maximum protruding height dimension H of the anti-slip protrusion 24 is preferably smaller than the radial thickness dimension T of the cylindrical portion 18 of the resin outer member 14, and more preferably is within a range of 1 / 4 to 1 / 2 of the thickness dimension T of the cylindrical portion 18. The axial length dimension L1 of the anti-slip protrusion 24 is preferably within a range of 1 / 10 to 1 / 2 of the axial length dimension L0 of the cylindrical portion 18 of the resin outer member 14, and more preferably is within a range of 1 / 7 to 1 / 4. The circumferential width dimension W1 of the anti-slip protrusion 24 is preferably within a range of 1 / 20 to 1 / 3 of the circumference of the cylindrical portion 18 of the resin outer member 14, and more preferably is within a range of 1 / 15 to 1 / 8.

[0037] The guide surface 30 has an inclination angle α with respect to the axial direction that is smaller than the inclination angle β of the stop surface 32 with respect to the axial direction. In this embodiment, the guide surface 30 has a constant inclination angle α with respect to the axial direction, and the stop surface 32 has a constant inclination angle β with respect to the axial direction. Therefore, the axial length dimension L2 of the guide surface 30 is larger than the axial length dimension L3 of the stop surface 32. The inclination angle α of the guide surface 30 is preferably formed within a range of 2 to 10 degrees. The inclination angle β of the stop surface 32 is preferably formed within a range of 20 to 30 degrees. In addition, the inclination angle α of the guide surface 30 can vary in the axial direction. Similarly, the inclination angle β of the stop surface 32 can also vary in the axial direction. Therefore, the guide surface 30 and the stop surface 32 are not limited to being formed by a single plane. For example, they can be formed by multiple planes with different inclination angles, or they can be formed by curved surfaces with continuously varying inclination angles.

[0038] The inner shaft member 12 is inserted through the inner periphery of the resin outer member 14, and these inner shaft member 12 and the resin outer member 14 are connected by a main rubber elastic body 16. The main rubber elastic body 16 is formed as a thick-walled, generally cylindrical shape. 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 cylindrical portion 18 of the resin outer member 14. The main rubber elastic body 16 is formed as an integral vulcanized molded part including the inner shaft member 12 and the resin outer member 14.

[0039] The lower end surface of the main rubber elastic body 16 is formed into a curved surface with a concave recess opening downward. A first stopper 36 is provided on the outer circumference of the main rubber elastic body 16, projecting downward. The first stopper 36 is affixed to the lower surface of the flange 20 of the resin outer member 14 and projects downward from the flange 20. A second stopper 38 is integrally provided at the outer circumferential end of the main rubber elastic body 16, covering the upper surface of the resin outer member 14 and projecting upward from the resin outer member 14.

[0040] like Figures 1 to 3 As shown, the subframe bracket 10 having the above-described structure is used while being fitted into a cylindrical sleeve member 40. The sleeve member 40, for example, constitutes a portion of the subframe and is formed into a substantially cylindrical shape with a mounting hole 42. The sleeve member 40 is a highly rigid member formed of metal such as iron.

[0041] The sleeve member 40 has a pair of windows 44, 44 formed on either side in the front-to-back direction. The windows 44 extend radially through the peripheral wall of the mounting hole 42. The windows 44 are formed into a generally quadrilateral shape when viewed in the front-to-back direction, and in this embodiment, are generally rectangular with rounded corners. The axially opposite sides of the opening periphery of the window 44 form first window-side opposing sides 46, 46, which serve as a pair of first pairs of sides located on a plane perpendicular to the axial direction. The circumferentially opposite sides form second window-side opposing sides 48, 48, which serve as a second pair of sides extending generally parallel to the axial direction.

[0042] The window portion 44 is formed to have a larger area when viewed in the front-back direction than the anti-slip protrusion 24 of the resin outer member 14. Figure 1 As shown, the ratio of the left and right width dimension of the window portion 44 to the upper and lower length dimension is formed to be larger than the ratio of the left and right width dimension of the anti-slip protrusion 24 to the upper and lower length dimension, and the window portion 44 is formed into a flat shape that is longer in the left and right direction than the anti-slip protrusion 24.

[0043] The axial length L4 of the window portion 44 is preferably greater than the axial length L1 of the retaining projection 24 of the resin outer member 14, and more preferably is at least 1.05 times the axial length L1 of the retaining projection 24. Furthermore, the circumferential width W2 of the window portion 44 is greater than the circumferential width W1 of the retaining projection 24 of the resin outer member 14. The circumferential width W2 of the window portion 44 is preferably within a range of 1.1 to 3 times the circumferential width W1 of the retaining projection 24, and more preferably within a range of 1.2 to 2 times.

[0044] The axial length L4 of the window portion 44 is preferably within a range of 1 / 8 to 1 / 2, and more preferably within a range of 1 / 5 to 1 / 3, of the axial length L5 of the sleeve member 40. Furthermore, the circumferential width W2 of the window portion 44 is preferably within a range of 1 / 30 to 1 / 3, and more preferably within a range of 1 / 20 to 1 / 5, of the circumference of the sleeve member 40.

[0045] The resin outer member 14 of the subframe bracket 10 is fitted into the mounting hole 42 of the collar member 40. The outer diameter of the cylindrical portion 18 of the resin outer member 14 is slightly larger than the inner diameter of the collar member 40, and the cylindrical portion 18 fits with the collar member 40 with radial interference. Furthermore, the flange 20 provided at the lower end of the resin outer member 14 abuts against the lower end surface of the collar member 40 in the vertical direction, thereby setting the relative axial position of the resin outer member 14 with respect to the collar member 40.

[0046] The outer peripheral surface of the upper end portion of the resin outer member 14 is formed into a tapered surface 22 that tapers upward, thereby enabling the resin outer member 14 to be easily inserted from below into the sleeve member 40. In this embodiment, the minimum outer diameter of the tapered surface 22 is formed to be smaller than the inner diameter of the sleeve member 40. By inserting the upper end of the resin outer member 14 into the sleeve member 40, the resin outer member 14 and the sleeve member 40 can be radially positioned relative to each other before insertion.

[0047] The anti-slip protrusion 24 protruding from the outer peripheral surface of the resin outer member 14 is inserted into the window portion 44 of the sleeve member 40. The protruding front end surface of the anti-slip protrusion 24 is formed with a guide surface 30 having an inclined shape that tapers toward the insertion direction toward the insertion front end side of the sleeve member 40. This makes it easier for the sleeve member 40 to pass over the anti-slip protrusion 24 and insert the anti-slip protrusion 24 into the window portion 44.

[0048] The lower opening peripheral edge of the window portion 44 (the first window-side opposite edge 46) is located on the retaining surface 32 of the retaining projection 24 and is axially retained by the retaining projection 24. This prevents the resin outer member 14 from being easily dislodged due to downward displacement relative to the sleeve member 40. In particular, in the synthetic resin outer member 14, the cylindrical portion 18 is embedded in the sleeve member 40. As a result, the force directed toward the inner circumference from the sleeve member 40 continues to act on the cylindrical portion 18. This may cause the cylindrical portion 18 to undergo plastic deformation (fatigue) due to long-term degradation, leading to a potential reduction in the resistance to dislodgment due to the engagement of the cylindrical portion 18 with the sleeve member 40. To address these unique issues of the resin outer member 14, a locking structure is provided in the axial direction between the anti-slip protrusion 24 and the opening peripheral edge of the window portion 44 of the sleeve member 40. Even if the resistance to fall out due to the fitting is reduced due to fatigue of the cylindrical portion 18 of the resin outer member 14, the locking structure of the anti-slip protrusion 24 can stably ensure the necessary resistance to fall out. Since the resin outer member 14 is made of synthetic resin, it has a high degree of freedom in shape, and the shape and size of the anti-slip protrusion 24 protruding from the outer peripheral surface can be set with great freedom.

[0049] The locking portion, or locking surface 32, of the first window-side opposite edge 46 of the anti-slip protrusion 24, located below the window portion 44, is formed in an inclined shape, tilted toward the outer periphery toward the front end in the insertion direction. Thus, even if the anti-slip protrusion 24 and the window portion 44 shift relative to each other in the axial direction, the first window-side opposite edge 46 remains stably positioned on the locking surface 32 of the anti-slip protrusion 24, thereby stably preventing the sleeve member 40 of the resin outer member 14 from falling out. In this embodiment, the edge 50 of the first window-side opposite edge 46 of the sleeve member 40 sinks into the locking surface 32 of the anti-slip protrusion 24, providing a stronger anti-slip effect. Furthermore, even if the anti-slip protrusion 24 and the window portion 44 shift relative to each other in the axial direction, the first window-side opposite edge 46 of the window portion 44 remains easily locked in contact with the locking surface 32 of the anti-slip protrusion 24. Furthermore, the first window-side opposite edge 46, having the edge 50, extends circumferentially in a plane orthogonal to the axial direction.

[0050] Furthermore, the inclination angle of the retaining surface 32 of the anti-slip convex portion 24 is formed to be larger than the inclination angle of the guide surface 30. Thus, the sleeve member 40 is guided by the guide surface 30 having a smaller inclination angle, making it easier for the sleeve member 40 to pass over the anti-slip convex portion 24. Furthermore, the retaining surface 32 having a larger inclination angle effectively retains the first window-side opposite edge 46 of the window portion 44, thereby providing greater resistance to the resin outer member 14 from falling off the sleeve member 40.

[0051] The anti-slip protrusions 24 and the windows 44 are provided on both radial sides of the resin outer member 14 and the sleeve member 40, respectively. Therefore, the resin outer member 14 exerts resistance to detachment from the sleeve member 40 on both radial sides where the anti-slip protrusions 24 and the windows 44 are formed, further reducing the likelihood of detachment of the resin outer member 14 from the sleeve member 40. Furthermore, the resistance to detachment of the resin outer member 14 from the sleeve member 40 acts on both radial sides, so the moments resulting from these resistances cancel each other out, thereby preventing tilting (rolling displacement) of the resin outer member 14 and the sleeve member 40 caused by the resistance.

[0052] The first convex-side opposing edge 26 of the anti-slip protrusion 24, formed by the retaining surface 32, and the first window-side opposing edge 46 of the window 44, which is retained by the retaining surface 32, both extend in a direction perpendicular to the axial direction. Consequently, the retaining portion between the retaining surface 32 of the anti-slip protrusion 24 and the first window-side opposing edge 46 of the window 44 extends in a direction perpendicular to the axial direction. Consequently, the retaining surface 32 of the anti-slip protrusion 24 and the first window-side opposing edge 46 of the window 44 more effectively exerts its resistance to axial detachment from the sleeve member 40.

[0053] The anti-dropout protrusion 24 is formed to have a smaller width in the axial direction than the window 44, so that Figure 1 、 Figure 2As shown, the first convex side opposite edge portion 26 on the upper side of the anti-slip protrusion 24 and the first window side opposite edge portion 46 on the upper side of the window portion 44 are spaced apart from each other in the axial direction. As a result, an axial gap 52 is formed axially between the first convex side opposite edge portion 26 on the upper side of the anti-slip protrusion 24 and the first window side opposite edge portion 46 on the upper side of the window portion 44. The axial gap 52 is continuously provided over the entire circumferential length of the anti-slip protrusion 24.

[0054] The anti-dropout protrusion 24 is formed to have a smaller width dimension in the circumferential direction than the window 44, so that Figure 1 、 Figure 3 As shown, the second convex side opposite edge portions 28 and the second convex side opposite edge portions 28 of the anti-slip protrusion 24 are spaced apart from the second window side opposite edge portions 48 and the second window side opposite edge portions 48 of the window portion 44 in the circumferential direction, and circumferential gaps 54 are formed between the second convex side opposite edge portions 28 and the second convex side opposite edge portions 28 and the second window side opposite edge portions 48 and the second window side opposite edge portions 48, respectively. The circumferential gaps 54 and the circumferential gaps 54 are continuously provided over the entire axial length of the anti-slip protrusion 24. In addition, the circumferential widths of the circumferential gaps 54 and the circumferential gaps 54 formed on both circumferential sides of the anti-slip protrusion 24 can be different from each other.

[0055] The circumferential gaps 54 and 54 are continuous with the axial gap 52 at the upper end, and these circumferential gaps 54 and 54 and the axial gap 52 constitute a gap 56 that extends continuously in a generally U-shaped shape that is reversed in the vertical direction around the anti-slip convex portion 24. Figure 1 As shown, in the gap 56 of the present embodiment, the width dimension D2 of the circumferential gap 54 in the circumferential direction is formed to be larger than the width dimension D1 of the axial gap 52 in the axial direction.

[0056] By forming such a gap 56, relative positional deviation and dimensional error between the anti-slip protrusion 24 in the resin outer member 14 and the window portion 44 of the sleeve member 40 are allowed by the gap 56. Therefore, for example, the anti-slip protrusion 24 is prevented from overlapping the inner periphery of the sleeve member 40 at a position offset from the window portion 44, and the engaging surface 32 of the anti-slip protrusion 24 is stably engaged with the first window-side opposing edge 46 on the lower side of the window portion 44, thereby effectively achieving the intended anti-slip effect.

[0057] In this embodiment, the width dimension D2 of the circumferential gap 54 is larger than the width dimension D1 of the axial gap 52. This allows for greater relative positional displacement between the retaining projection 24 of the resin outer member 14 and the window 44 of the sleeve member 40 in the circumferential direction than in the axial direction. Both the retaining projection 24 and the window 44 are positioned radially apart relative to the central axis O of the sub-frame bracket 10 and the sleeve member 40. As a result, even when the resin outer member 14 and the sleeve member 40 are displaced circumferentially at a small rotational angle, the relative displacement between the retaining projection 24 and the window 44 is likely to be relatively large. Therefore, in the circumferential direction, where significant positional displacement is likely to occur, the large width of the circumferential gap 54 and the tolerance for displacement caused by the circumferential gap 54 prevent the retaining projection 24 from falling out of the window 44 during assembly of the sub-frame bracket 10 to the sleeve member 40.

[0058] In this embodiment, the anti-slip protrusion 24 and the window portion 44 are each formed into a substantially rectangular shape, and the first convex side opposite edge portion 26 of the anti-slip protrusion 24 and the first window side opposite edge portion 46 of the window portion 44, which are separated by an axial gap 52, are circumferentially opposed to each other at a predetermined distance. Therefore, the width dimension D1 of the axial gap 52 can be formed so as not to be excessively large and to allow for axial relative positional offset between the anti-slip protrusion 24 and the window portion 44 with good spatial efficiency. In addition, the second convex side opposite edge portion 28 and the second convex side opposite edge portion 28 of the anti-slip protrusion 24 and the second window side opposite edge portion 48 and the second window side opposite edge portion 48 of the window portion 44, which are separated by a circumferential gap 54, are axially opposed to each other at a predetermined distance. Therefore, the width dimension D2 of the circumferential gap 54 can be formed so as not to be excessively large and to allow for circumferential relative positional offset between the anti-slip protrusion 24 and the window portion 44 with good spatial efficiency.

[0059] Above, embodiments of the present invention have been described in detail, but the present invention is not limited to its specific record. For example, in the above-mentioned first embodiment, the examples of the anti-slip convex portion 24 and the window portion 44 being formed on both sides in the radial direction are shown, but the formation quantity of the anti-slip convex portion 24 and the window portion 44 is not particularly limited, and can be each one, or can be each more than two. In addition, when each multiple anti-slip convex portion 24 and the window portion 44 are set, these anti-slip convex portions 24 and the window portion 44 are preferably uniformly dispersed in the circumferential direction, but as long as the anti-slip convex portion 24 and the window portion 44 are arranged in positions corresponding to each other, the configuration on the circumferential direction is just not limited.

[0060] In addition, a plurality of sets of anti-slip protrusions 24 and windows 44 may be provided at mutually different positions in the axial direction. Furthermore, when multiple sets of anti-slip protrusions 24 and windows 44 are provided in the circumferential direction, the axial positions of the multiple sets of anti-slip protrusions 24 and windows 44 provided at different circumferential positions may be different from each other.

[0061] The shape of the anti-slip convex portion when observing in the protruding direction is not necessarily limited to a square or a rectangle. For example, it can be a quadrilateral such as a trapezoid or a parallelogram, or a polygon such as a triangle or a pentagon or more, or a circle including an ellipse. In addition, the opening shape of the window portion is not necessarily limited to a square or a rectangle, and can be various shapes in the same manner as the anti-slip convex portion. In addition, the anti-slip convex portion and the window portion that is locked with the anti-slip convex portion are preferably formed as shapes corresponding to each other when observing in the protruding direction of the anti-slip convex portion 24, or can be shapes different from each other.

[0062] The guide surface 30 of the anti-slip protrusion 24 is not essential. For example, if the inner circumference of the opening portion of the sleeve member 40, into which the resin outer member 14 is inserted, is formed into an expanded tapered surface, even if the anti-slip protrusion 24 does not have the guide surface 30, the anti-slip protrusion 24 can easily pass over the sleeve member 40 when the resin outer member 14 is inserted into the sleeve member 40. Furthermore, the front end surface 34 of the anti-slip protrusion 24 may not be required. For example, the guide surface 30 and the locking surface 32 may be provided directly and continuously without the front end surface 34.

[0063] The axial length L1 of the retaining projection 24 may be greater than the axial length L4 of the window 44. In this case, a portion of the retaining surface 32 of the retaining projection 24 is axially offset from the window 44, thereby forming an axial gap 52.

[0064] In the first embodiment described above, the subframe bracket 10 is shown as an example of a cylindrical vibration isolation device, but the cylindrical vibration isolation device involved in the present invention is not only applicable to subframe brackets, but is also preferably applicable to, for example, engine brackets, motor brackets, torque rods, suspension bushings, etc.

Claims

1. A cylindrical vibration isolation device (10), wherein an inner shaft member (12) is inserted into a cylindrical resin outer member (14), and the inner shaft member (12) and the resin outer member (14) are connected via a main rubber elastic body (16), wherein: The resin outer member (14) is provided with an anti-slip convex portion (24) protruding from the outer peripheral surface. A window portion (44) for inserting the anti-dropout protrusion (24) is formed in a cylindrical sleeve member (40) for embedding the resin outer member (14). Around the anti-slip convex portion (24), a gap (56) is provided between the anti-slip convex portion (24) and the window portion (44) on the front end side and both sides of the circumferential direction of the embedding direction of the resin outer member (14) into the sleeve member (40). The end surface of the resin outer component (14) in the anti-slip convex portion (24) on the base end side of the embedding direction of the sleeve component (40) is formed as a locking surface (32) inclined toward the outer periphery and toward the front end side of the embedding direction, and the sleeve component (40) is axially locked relative to the locking surface (32).

2. The cylindrical anti-vibration device (10) according to claim 1, wherein: The end surface of the anti-slip convex portion (24) on the front end side of the embedding direction of the resin outer member (14) into the sleeve member (40) is formed as a guide surface (30) inclined toward the outer periphery and toward the base end side of the embedding direction. The inclination angle of the guide surface (30) relative to the embedding direction is formed to be smaller than the inclination angle of the stop surface (32).

3. The cylindrical anti-vibration device (10) according to claim 1 or 2, wherein: The anti-slip convex portions (24) are respectively arranged on both sides in the radial direction.

4. The cylindrical anti-vibration device (10) according to claim 1 or 2, wherein: The gap (56) is formed so as to be larger in the circumferential direction between the anti-slip protrusion (24) and the window portion (44) than in the axial direction.

5. The cylindrical anti-vibration device (10) according to claim 1 or 2, wherein: The stop surface (32) of the anti-slip convex portion (24) and the opening peripheral edge of the window portion (44) in the sleeve member (40) that is stopped by the stop surface (32) both extend in a direction perpendicular to the axial direction.

6. The cylindrical anti-vibration device (10) according to claim 5, wherein: The anti-slip convex portion (24) and the window portion (44) include a pair of first side portions (26, 46) extending in a direction perpendicular to the axial direction when viewed in the protruding direction of the anti-slip convex portion (24) and a pair of second side portions (28, 48) extending in the axial direction.

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