Suspension system and strut mount

Abstract

To provide a suspension device and a strut mount capable of suppressing noise in a vehicle.SOLUTION: A suspension device 1 is equipped with a damper rod 2, and a strut mount 3. The strut mount has a bracket 31 configured to be attached to a vehicle body side, a shaft 32 attached to the damper rod so as to extend in a shaft axis SA vertical to a rod axial direction RA of the damper rod, and a pair of bushes 33 provided coaxially with the shaft axis so as to couple the shaft and the bracket at both ends of the shaft. Each bush has an outer cylinder 331 in contact with the bracket, an inner cylinder 332 in contact with the shaft, and a body rubber 333 coupling the outer cylinder and the inner cylinder. The body rubber of each bush has a bore 3335 on both sides in the rod axial direction with respect to the shaft.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] This invention relates to a suspension device and a strut mount.

Background Art

[0002] Conventionally, there has been a strut mount including a bracket configured to be attached to the vehicle body side and a main rubber (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the conventional technology, there has been room for improvement regarding vehicle interior noise.

[0005] An object of this invention is to provide a suspension device and a strut mount capable of suppressing vehicle interior noise.

Means for Solving the Problems

[0006] 〔1〕A suspension device including a damper rod and a strut mount, wherein the strut mount includes a bracket configured to be attached to the vehicle body side, and a shaft attached to the damper rod so as to extend along a shaft axis perpendicular to the rod axis direction of the damper rod, and ​​At both ends of the shaft, a pair of bushings are provided coaxially with the shaft axis to connect the shaft and the brackets to each other, It has, Each of the bushes is, An outer cylinder in contact with the bracket, An inner cylinder in contact with the aforementioned shaft, The main body rubber connects the outer cylinder and the inner cylinder, It has, A suspension device in which the main rubber of each bush has grease on both sides in the direction of the rod axis relative to the shaft. This helps to reduce noise inside the vehicle.

[0007] [2] Further equipped with a lower ball joint, The suspension device according to [1], wherein the shaft axis is substantially perpendicular to a virtual plane that includes the central axis of a virtual cylinder circumscribing the trajectory of the center point of the lower ball joint during the stroke of the suspension device and the pivot point of the damper rod during the stroke of the suspension device. This will further reduce noise inside the vehicle.

[0008] [3] The suspension device according to [1] or [2], wherein the damper rod swings along a virtual plane perpendicular to the shaft axis during the stroke of the suspension device. This will further reduce noise inside the vehicle.

[0009] The strut mount used in the suspension device described in any one of [4] [1] to [3]. This helps to reduce noise inside the vehicle. [Effects of the Invention]

[0010] This invention provides a suspension system and a strut mount that can suppress in-vehicle noise. [Brief explanation of the drawing]

[0011] [Figure 1] The figure is a top view showing the main body of the strut mount according to an embodiment of the present invention as viewed from above in the rod height direction. [Figure 2] The figure is a view B showing the main body of FIG. 1 as viewed in the direction of arrow B in FIG. 1. [Figure 3] The figure is a view C showing the main body of FIG. 1 as viewed in the direction of arrow C in FIG. 1. [Figure 4] The figure is a cross-sectional view taken along line A-A in FIG. 1, showing a part of the suspension device according to an embodiment of the present invention provided with the strut mount of FIG. 1. [Figure 5] The figure corresponds to FIG. 3 and is for explaining the operation during the stroke of the suspension device. [Figure 6] The figure schematically shows a part of the suspension device of FIG. 4 and is for explaining the operation during the stroke of the suspension device.

Embodiments for Carrying Out the Invention

[0012] The suspension device and the strut mount according to the present invention are suitable for application to a MacPherson strut type suspension device. Hereinafter, embodiments of the suspension device and the strut mount according to the present invention will be exemplarily described with reference to the drawings.

[0013] FIGS. 1 to 6 are drawings for explaining a suspension device 1 according to an embodiment of the present invention and a strut mount 3 according to an embodiment of the present invention. FIG. 6 schematically shows a part of the suspension device 1 according to the present embodiment. The suspension device 1 according to the present embodiment is configured as a MacPherson strut type suspension device. The suspension device 1 is provided in a vehicle. As shown in FIG. 6, the suspension device 1 of the present embodiment includes a strut mount 3 according to an embodiment of the present invention, a shock absorber 5, a spring 4, a lower arm 8, a lower ball joint 7, a hub (not shown), and a knuckle (not shown). The shock absorber 5 has a damper rod 2 and a cylinder 6. The cylinder is located below the damper rod 2 and is arranged coaxially with the central axis of the damper rod 2 (hereinafter referred to as the "rod axis RA"). The strut mount 3 is attached to the upper end of the damper rod 2. The spring 4 is configured to support the damper rod 2 and the strut mount 3 integrally in an upwardly biased state so as to be movable downward. The lower end of the spring 4 is supported by a receiving portion 9 fixed to the cylinder 6 of the shock absorber 5. The lower ball joint 7 is located below the shock absorber 5. The lower end of the shock absorber 5 (that is, the lower end of the cylinder 6) and the lower ball joint 7 are connected via a knuckle (not shown). The knuckle (not shown) protrudes inward in the vehicle left-right direction KI from the hub (not shown). The hub (not shown) rotatably supports a wheel (not shown; for example, a front wheel). The lower arm 8 has an extension portion 81 extending along the vehicle left-right direction K and a pair of bushes 82. The pair of bushes 82 are provided at the inner end in the vehicle left-right direction KI of the extension portion 81 and are spaced apart from each other in the vehicle front-rear direction J. The lower ball joint 7 is attached to the outer end in the vehicle left-right direction KO of the lower arm 8.

[0014] In this specification, the inner side in the vehicle left-right direction KI refers to the side closer to the center of the vehicle in the vehicle left-right direction K. On the other hand, the outer side in the vehicle left-right direction KO refers to the side farther from the center of the vehicle in the vehicle left-right direction K. Also, in this specification, the direction parallel to the rod axis RA is referred to as the "rod axis direction RAD". In this specification, the side closer to the rod axis RA is referred to as the "inner circumference side of the rod," the side further from the rod axis RA is referred to as the "outer circumference side of the rod," the circumferential direction centered on the rod axis RA is referred to as the "circumferential direction of the rod," and the radial direction centered on the rod axis RA is referred to as the "radial direction of the rod."

[0015] As indicated by the arrows in Figures 1 to 6, for convenience, this specification defines the mount width direction X, the mount depth direction Y, and the mount height direction Z, which are fixed to the strut mount 3 and are perpendicular to each other.

[0016] As shown in Figure 4, the strut mount 3 of this embodiment comprises a main body 3M, a bearing 34, and a spring seat 35. The main body 3M includes a bracket 31, a shaft 32, and a pair of bushings 33. Figures 1-3 and 5 show only the main body 3M of the strut mount 3.

[0017] The bracket 31 is configured to be attached to the vehicle body. As shown in Figures 1 to 4, in this embodiment, the bracket 31 has a main body portion 311 and a flange portion 312. The main body 311 is configured in a cylindrical shape extending in the mount height direction Z, and consequently has a central through-hole 313 extending in the mount height direction Z. The mount height direction Z is parallel to the central axis of the central through-hole 313. As shown in Figure 4, the central through-hole 313 of the bracket 31 is configured so that the upper end of the damper rod 2 is inserted into it. When the vehicle is stationary, the rod axis direction RAD is aligned with the mount height direction Z. The flange portion 312 protrudes from the upper part of the main body portion 311 toward the outer circumference of the rod. The flange portion 312 has a plurality of fastening holes 315 (three in the example shown in the figure). The flange portion 312 is configured to be attached to the vehicle body by passing a plurality of fasteners F1 (three in the example shown in the figure) through these fastening holes 315 and tightening them toward the vehicle body. The fasteners F1 are, for example, bolts. However, the bracket 31 may be configured to be attached to the vehicle body by means other than fastening by the fastener F1.

[0018] As shown in Figure 6, when the vehicle is stationary, the rod axis RA is approximately parallel to the vehicle's vertical direction L, and may be inclined at an acute angle to the vehicle's vertical direction L, for example, as in the example in Figure 6. More specifically, in the example in Figure 6, the rod axis RA extends inward KI in the left-right direction of the vehicle as it moves upward.

[0019] For convenience, the damper rod 2 is shown with a dashed line in Figures 3 and 5.

[0020] The suspension device 1 shown in Figure 4 is in a stationary vehicle state. The damper rod 2, shown by the dashed line in Figure 3, is in the same state as in Figure 4. As shown in Figure 4, the shaft 32 extends along the mount width direction X. The shaft 32 is configured to be attached to the upper end of the damper rod 2. More specifically, the shaft 32 has a through hole 32h in the center of its mounting width direction X, through which the shaft 32 passes in the mounting height direction Z. On the other hand, the damper rod 2 has a mounting portion 21 at its upper end. The mounting portion 21 has a smaller diameter than the portion of the damper rod 2 below the mounting portion 21. A male thread is formed on the outer circumference side of the mounting portion 21. The damper rod 2 has a stepped surface 22 that extends from the lower end of the mounting portion 21 towards the outer circumference of the rod and faces upward. The shaft 32 is configured to be attached to the damper rod 2 by inserting the mounting portion 21 of the damper rod 2 into the through hole 32h of the shaft 32, and tightening it from the upper side ZU in the mounting height direction with a fastener F2 such as a nut, with the lower side ZL of the shaft 32 in contact with the stepped surface 22 of the damper rod 2. However, the shaft 32 may be configured to be attached to the damper rod 2 by a structure different from that of this example. The shaft 32 is configured to be attached to the damper rod 2 so as to extend along a shaft axis SA that is perpendicular to the rod axis direction RAD. The shaft axis SA is the central axis of the shaft 32. The mount width direction X is parallel to the shaft axis SA.

[0021] In this specification, the direction parallel to the shaft axis SA is referred to as the "shaft axis direction SAD". In this specification, the side closer to the shaft axis SA is referred to as the "inner shaft side," the side further from the shaft axis SA is referred to as the "outer shaft side," the circumferential direction centered on the shaft axis SA is referred to as the "circumferential shaft direction," and the radial direction centered on the shaft axis SA is referred to as the "radial shaft direction."

[0022] As shown in Figures 2 to 4, the main body 311 of the bracket 31 has a pair of side through holes 314 that penetrate the main body 311 in the direction SAD of the shaft axis relative to the central through hole 313. The side through holes 314 are demarcated by the hole section 316 of the bracket 31. The pair of side through holes 314 communicate with the central through hole 313 and are coaxial with the shaft axis SA. The ends 321 on both sides of the shaft 32 in the shaft axial direction SAD are located inside a pair of side through holes 314. The diameter of the outer circumferential surface of each end 321 of the shaft 32 is smaller than the diameter of each side through hole 314.

[0023] A pair of bushings 33 are provided at both ends 321 of the shaft 32 in the shaft axial direction SAD. The pair of bushings 33 are provided coaxially with the shaft axis SA. The pair of bushings 33 are located on the outer circumference of the shaft at both ends 321 of the shaft 32 in the shaft axial direction SAD, inside a pair of side through holes 314 of the bracket 31. The pair of bushings 33 connect the shaft 32 and the bracket 31 to each other, specifically connecting the ends 321 of the shaft 32 to a pair of holes 316 of the bracket 31.

[0024] As shown in Figures 3 and 4, each bush 33 has an outer cylinder 331, an inner cylinder 332, and a rubber body 333. The outer cylinder 331 is in contact with the bracket 31, specifically with the hole screen 316 of the bracket 31. The inner cylinder 332 is positioned at a distance from the outer cylinder 331 towards the inner circumference of the shaft. The inner cylinder 332 is in contact with the shaft 32, specifically, with the outer surface of the end 321 of the shaft 32 in the shaft axial direction SAD. The main rubber body 333 is made of rubber. The main rubber body 333 is located between the outer cylinder 331 and the inner cylinder 332 in the shaft radial direction, and connects the outer cylinder 331 and the inner cylinder 332 to each other.

[0025] As shown in Figures 3 to 4, in this example, the main rubber body 333 of each bush 33 has, respectively, an outer annular portion 3331, an inner annular portion 3332, a pair of connecting portions 3333, a pair of protruding portions 3334, and a pair of tufts 3335. The outer annular portion 3331 is configured in an annular shape so as to extend over the entire circumference in the circumferential direction of the shaft. The outer surface of the outer annular portion 3331 on the shaft's outer circumference side is in contact with the inner surface of the outer cylinder 331 on the shaft's inner circumference side. The inner annular portion 3332 is configured in an annular shape so as to extend over the entire circumference in the circumferential direction of the shaft. The inner surface of the inner annular portion 3332 on the shaft's inner side is in contact with the outer surface of the inner cylinder 332 on the shaft's outer side. The pair of connecting portions 3333 are located on both sides in the mounting depth direction Y relative to the shaft 32, and connect the outer annular portion 3331 and the inner annular portion 3332. The pair of projections 3334 are located on both sides of the rod axial direction RAD relative to the shaft 32. Each projection 3334 has its inner circumference end connected to the inner annular portion 3332 and protrudes toward the outer annular portion 3331. The outer circumference end of each projection 3334 is located further inward than the outer annular portion 3331. A pair of curb fins 3335 are located on either side of the shaft 32 in the rod axial direction RAD. Each curb fin 3335 penetrates the main rubber 333 in the shaft axial direction SAD. Each curb fin 3335 is located between a pair of connecting portions 3333 in the shaft circumferential direction. More specifically, each curb fin 3335 is partitioned between the outer annular portion 3331, the pair of connecting portions 3333, and the protruding portion 3334. Each curb fin 3335 has a narrow portion 3335n and a pair of wide portions 3335w. The narrow portion 3335n is partitioned between the shaft inner circumferential surface of the outer annular portion 3331 and the shaft outer circumferential surface of the protruding portion 3334. The pair of wide portions 3335w are located on either side of the narrow portion 3335n in the shaft circumferential direction. The narrow section 3335n has a shaft radial width that is narrower than the pair of wide sections 3335w.

[0026] A pair of bushings 33 are positioned between the bracket 31 and the shaft 32, for example, by press-fitting.

[0027] As shown in Figure 4, the bearing 34 is located on the outer circumference of the rod, relative to the shaft 32 and the pair of bushings 33, and is in contact with the flange portion 312 of the bracket 31 from the lower side ZL in the mounting height direction. The spring seat 35 is in contact with the bearing 34 from the lower side ZL in the mounting height direction. The upper end of the spring 4 is in contact with the spring seat 35 from the lower side ZL in the mounting height direction. The bearing 34 supports the main body 3M of the strut mount 3 so that it can rotate around the rod axis RA relative to the spring seat 35 (and thus the spring 4). This allows it to absorb the rotation of the spring 4, for example, when the vehicle rolls over.

[0028] When assembling the strut mount 3 of this embodiment, for example, first, with the shaft 32 positioned inside the bracket 31, a pair of bushings 33 are inserted into the pair of side through holes 314 from both outer sides in the mount width direction X by press-fitting or the like, thereby connecting the bracket 31 and the shaft 32 via the pair of bushings 33. After that, the bearing 34 and the spring seat 35 are assembled from the lower side ZL in the mount height direction toward the flange portion 312 of the bracket 31.

[0029] In this embodiment, as described above, the shaft 32 is attached to the damper rod 2 so as to extend along the shaft axis SA which is perpendicular to the rod axis direction RAD, and a pair of bushes 33 are provided coaxially with the shaft axis SA at both ends 321 of the shaft 32 so as to connect the shaft 32 and the bracket 31, and the main rubber body 333 of each bush 33 has a groove 3335 on both sides of the rod axis direction RAD relative to the shaft 32. The presence of the spur 3335 on both sides of the rod axis RAD in the main rubber 333 allows for a lower rigidity of the main rubber 333 in the vertical direction compared to a case where the spur 3335 are not positioned on both sides of the rod axis RAD. As a result, when minute vertical displacements such as road noise occur, minute vibrations are less likely to be transmitted, thus reducing in-vehicle noise. Furthermore, when larger vertical displacements occur, the protrusion 3334 contacts the outer cylinder 331 (via the outer annular portion 3331) on either side of the rod axial direction RAD relative to the shaft 32 (and consequently, the narrow portion 3335n of the spur 3335 is eliminated), thereby adding the rigidity of the protrusion 3334 to the overall spring rigidity. This significantly increases the overall spring rigidity, allowing the damping force of the shock absorber 5 to be utilized effectively. Furthermore, since the damper rod 2 is softly supported in the circumferential direction of the shaft by the main rubber 333 (via the shaft 32), as shown in Figures 5 and 6, it is integrated with the shaft 32 and can easily swing (twist displace) in the circumferential direction of the shaft around the shaft axis SA relative to the bracket 31. As a result of this swing in the circumferential direction of the shaft, the main rubber 333 twists in the circumferential direction of the shaft, but the width of the spur 3335 does not change much or at all, so it is possible to suppress the increase in spring stiffness caused by the elimination of the narrow portion 3335n of the spur 3335. Therefore, for example, when the suspension device 1 is stroking, it is possible to suppress the increase in spring stiffness when the damper rod 2 swings (twist displaces) in the circumferential direction of the shaft, and consequently, it is possible to effectively suppress the transmission of road noise to the vehicle body regardless of the vehicle posture and reduce in-vehicle noise. As described above, vibration absorption can be achieved independently in the direction of minute displacement and the direction of oscillation (torsion displacement).

[0030] In Figures 5 and 6, the symbol RA' indicates the rod axis RA at a timing different from that shown in each figure during the oscillation of the damper rod 2. During the stroke of the suspension device 1, as shown in Figure 6, the extension 81 of the lower arm 8 rotates around the central axis 82c of the pair of front and rear bushes 82 as indicated by arrow D. Consequently, the shock absorber 5 (and thus the damper rod 2) oscillates around the pivot point P as indicated by arrow E. The pivot point P is preferably located at the intersection of the shaft axis SA and the rod axis RA, as shown in Figure 4.

[0031] The suspension device 1 is preferably configured such that, as shown in Figures 5 and 6, the damper rod 2 swings along a virtual plane VP perpendicular to the shaft axis SA (i.e., approximately parallel to the virtual plane VP) during the stroke of the suspension device 1. Here, the virtual plane VP is a virtual plane that includes the mount height direction Z and the mount depth direction Y. As a result, the oscillation (torsion displacement) during the stroke of the suspension device 1 mainly occurs in the circumferential direction of the shaft, allowing the effects of the main body rubber 333 described above to be effectively utilized, effectively absorbing the oscillation (torsion displacement) during the stroke of the suspension device 1, and further suppressing in-vehicle noise.

[0032] As shown in Figure 6, it is preferable that the shaft axis SA of the suspension device 1 is substantially perpendicular (more preferably perpendicular) to a virtual plane VP that includes the central axis VCO of a virtual cylinder VC that tangent to the trajectory 7ct of the center point 7c of the lower ball joint 7 during the stroke of the suspension device 1, and the pivot point P of the damper rod 2 during the stroke of the suspension device 1. As a result, the oscillation (torsion displacement) during the stroke of the suspension device 1 mainly occurs in the circumferential direction of the shaft, allowing the effects of the main body rubber 333 described above to be effectively utilized, effectively absorbing the oscillation (torsion displacement) during the stroke of the suspension device 1, and further suppressing in-vehicle noise. Here, the virtual cylinder VC is, in other words, a virtual cylinder that minimizes the trajectory 7ct of the center point 7c of the lower ball joint 7 during the stroke of the suspension device 1. The trajectory 7ct of the center point 7c of the lower ball joint 7 during the stroke of the suspension device 1 is approximately arc-shaped.

[0033] The strut mount 3 may have any configuration different from the above embodiment, as long as the shaft 32 is attached to the damper rod 2 such that the shaft 32 extends along the shaft axis SA perpendicular to the rod axis RAD, and a pair of bushes 33 are provided coaxially with the shaft axis SA at both ends 321 of the shaft 32 so as to connect the shaft 32 and the bracket 31 to each other, and the main rubber 333 of each bush 33 has a groove 3335 on both sides of the rod axis RAD relative to the shaft 32.

[0034] For example, in the main rubber body 333, the protruding portion 3334 may be connected to the outer annular portion 3331 rather than the inner annular portion 3332, thereby the narrow portion 3335n of the currant 3335 may be partitioned between the inner annular portion 3332 and the protruding portion 3334.

[0035] Furthermore, although the bracket 31 of the strut mount 3 in the above-described embodiment is configured to facilitate the assembly of the strut mount 3 as described above, the configuration of the bracket 31 may differ from that of the above-described embodiment. The bearing 34 and spring seat 35 may also be different from those in the embodiment described above.

[0036] Furthermore, the configuration of the parts of the suspension device 1 other than the strut mount 3 may differ from that of the embodiment described above. [Industrial applicability]

[0037] The suspension device and strut mount according to the present invention are preferably applied to a MacPherson strut type suspension system. [Explanation of Symbols]

[0038] 1: Suspension system, 2: Damper rod, 21: Mounting part, 22: Stepped surface, 3: Strut mount, 3M: Main body, 31: Bracket, 311: Main body, 312: Flange, 313: Central through hole, 314: Side through hole, 315: Fastening hole, 316: Hole section screen 32: shaft, 32h: through hole, 321: end, 33: Bush, 331: Outer cylinder, 332: Inner cylinder, 333: Main rubber, 3331: Outer ring part, 3332: Inner ring part, 3333: Connecting part, 3334: Protruding part, 3335: Currant, 3335n: Narrow part, 3335w: Wide part 34: Bearings, 35: Spring seat, 4: Spring, 5: Shock absorber, 6: Cylinder, 7: Lower ball joint, 7c: Center point, 7ct: Trajectory 8: Lower arm, 81: Extension, 82: Bushing, 82c: Center axis, 9: Receiving section, RA, RA ’ : Rod axis, RAD: Rod axis direction, SA: Shaft axis, SAD: Shaft axis direction, VC: virtual cylinder, VCO: central axis, P: pivot point, VP: virtual plane F1, F2: Fasteners, X: Mount width direction, Y: Mount depth direction, Z: Mount height direction, ZU: Mount height direction upper side, ZL: Mount height direction lower side J: Front-to-back direction of the vehicle, K: Left-to-right direction of the vehicle, KO: Outer left-to-right direction of the vehicle, KI: Inner left-to-right direction of the vehicle, L: Up-to-down direction of the vehicle

Claims

1. damper rod and Strut mount and A suspension device comprising, The strut mount is, A bracket configured to be attached to the vehicle body, A shaft is attached to the damper rod so as to extend along a shaft axis perpendicular to the rod axis direction of the damper rod, At both ends of the shaft, a pair of bushings are provided coaxially with the shaft axis to connect the shaft and the brackets to each other, It has, Each of the bushes is, An outer cylinder in contact with the bracket, An inner cylinder in contact with the aforementioned shaft, The main body rubber connects the outer cylinder and the inner cylinder, It has, A suspension device in which the main rubber of each bush has grease on both sides in the direction of the rod axis relative to the shaft.

2. It also features a lower ball joint, The suspension device according to claim 1, wherein the shaft axis is substantially perpendicular to a virtual plane that includes the central axis of a virtual cylinder circumscribing the trajectory of the center point of the lower ball joint during the stroke of the suspension device and the pivot point of the damper rod during the stroke of the suspension device.

3. The suspension device according to claim 1, wherein the damper rod swings along a virtual plane perpendicular to the shaft axis during the stroke of the suspension device.

4. The strut mount used in the suspension device according to any one of claims 1 to 3.

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