Spring element, in particular jounce bumper, for a vehicle suspension

Abstract

A spring element, in particular a jounce bumper, for a vehicle suspension contains a longitudinal axis, a base body extending along the longitudinal axis, and an end portion positioned on a base end of the base body. The base body is elastically deformable between an uncompressed basic state and a compressed state in which the base body is at least partially compressed in the direction of the longitudinal axis. The end portion is configured for mounting the base body in a mounting cap. It is suggested that the end portion contains a plurality of at least two radially extending retention elements that are spaced apart from one another in the direction of the longitudinal axis, and each of the retention elements are configured to engage a mating retention element provided on the mounting cap.

Claims

1-13: (canceled)

14: A spring element for a vehicle suspension, comprising: a longitudinal axis and a base body extending along the longitudinal axis, the base body being elastically deformable between an uncompressed basic state and a compressed state in which the base body is at least partially compressed in the direction of the longitudinal axis, and an end portion positioned on a base end of the base body, said end portion being configured for mounting the base body in a mounting cap; wherein the end portion comprises at least two radially extending retention elements that are spaced apart from one another in the direction of the longitudinal axis, and each of the at least two radially extending retention elements are configured to engage one of at least two mating retention elements provided on the mounting cap to form a mating relationship, and wherein the at least two mating retention elements are configured to engage one another in a positive fit.

15: The spring element of claim 14, wherein the mating relationship comprises a protrusion and a recess formed by one of each of the at least two radially extending retention elements and the at least two mating retention elements, wherein the recess is dimensioned to accommodate the protrusion.

16: The spring element of claim 14, wherein at least one of the at least two radially extending retention elements is formed as a number of segments, wherein each of the segments extends along a portion of a circumference of the base body.

17: The spring element of claim 14, wherein one of the at least two radially extending retention elements is positioned at the base end of the base body.

18: The spring element of claim 14, wherein at least one of the at least two radially extending retention elements defines a first flank facing the base end and a second flank facing away from the base end.

19: The spring element of claim 18, wherein the first flank comprises a chamfered surface portion.

20: The spring element of claim 18, wherein the second flank comprises a surface portion that extends radially with respect to the longitudinal axis or that is undercut.

21: The spring element of claim 14, wherein the base body comprises an outside surface, and wherein the at least two radially extending retention elements protrude from the outside surface and connect to the base body through a transition radius.

22: The spring element of claim 17, wherein the at least two radially extending retention elements comprise a peripheral surface, and a chamfered surface connects to the peripheral surface through a transition radius.

23: The spring element of claim 14, wherein the base body is partly or completely composed of an elastomer that is compressible in volume.

24: A jounce bumper assembly, having a mounting cap, and the spring element according to claim 14, wherein the spring element is mounted in the mounting cap; and wherein the at least two mating retention elements are mated to and engaged with the at least two radially extending retention elements.

25: A vehicle, comprising a number of vehicle suspensions, wherein at least one of the vehicle suspensions comprises the jounce bumper assembly as claimed in claim 24.

26: The spring element of claim 14, wherein the spring element is a jounce bumper.

27: The spring element of claim 14, wherein the at least two radially extending retention elements are elastically deformable between an uncompressed basic state and a compressed state.

28: (N The spring element of claim 14, wherein the at least two radially extending retention elements are oversized when compared to the at least two mating retention elements.

29: The spring element of claim 16, wherein the segments are lip segments.

30: The spring element of claim 21, wherein the transition radius is 0.1 mm or greater.

31: The spring element of claim 22, wherein the transition radius is 0.1 mm or greater.

32: The spring element of claim 23, wherein the base body is partly or completely composed of a cellular polyisocyanate polyaddition product.

33: The vehicle of claim 25, wherein each of the vehicle suspensions comprises the jounce bumper assembly.

Description

[0047] The invention will hereinafter be described in more detail with reference to the accompanying drawings of a preferred embodiments herein,

[0048] FIG. 1 shows a schematic side view of a spring element according to a preferred embodiment,

[0049] FIG. 2 shows a schematic cross sectional view through the spring element of FIG. 1,

[0050] FIG. 3 shows a schematic detail view of the spring element shown in FIG. 2, and

[0051] FIG. 4a-c show schematic representations of a jounce bumper assembly having a spring element as shown in FIGS. 1-3.

[0052] A spring element 1 is shown in FIG. 1. The spring element 1 comprises a longitudinal axis L along which a base body 3 extends. The base body 3 is shown in the uncompressed base state.

[0053] The base body 3 comprises a base end 4 and a tip end 6. The base end 4, in operation, faces towards a vehicle structure to which the spring element 1 is mounted either immediately or through other parts. The tip end 6, in operation, faces a damper cap or similar element which causes compression of the spring element upon impact.

[0054] On the side of the base end 4, the base body 3 comprises an end portion 5 configured from mounting the spring element 1 to a mounting cap (cf. FIGS. 4a-c).

[0055] The end portion 5 comprises a plurality of retention elements 7a, b that are axially spaced apart from one another in the direction of the longitudinal axis L. In the exemplary embodiment shown in FIGS. 1-3, the retention elements 7a, 7b are both formed as singular protrusions, or lips, which extend along the entire circumference of the base body 3. It would however also be within the scope of the invention if one or both of the retention elements 7a, b were formed as segmented protrusions wherein each segment only extends along a portion of the circumference of the base body 3 and in which the segments are preferably spaced apart from one another in the circumferential direction.

[0056] As can be seen in FIG. 2, the base body 3 comprises a recess 9 extending from the base end 4 through to the tip end 6. The recess 9 comprises a stepped inner diameter having a first stop shoulder 11 and a cylindrical side wall 13. The stop shoulder 11 and cylindrical side wall 13 are configured to receive and centre a mounting cap (cf. FIGS. 4a-c). The recess on the base end 4 further comprises an inclined insertion surface, preferably having a conical or tapered surface portion which facilitates the installation of the spring element 1 on the mounting cap (cf. FIGS. 4a-c).

[0057] As can be seen from FIG. 3, the retention elements 7a, 7b comprise a diameter which is optimized for easy installation and at the same time stable retention functionality. The first retention element 7a is located on the base end 4 of the spring element 7. The second retention element 7b is spaced apart from the base end 4 and from the first retention element 7a in the direction of the longitudinal axis L (see FIGS. 1 and 2).

[0058] The first retention element 7a comprises a peripheral surface 18 and a transition radius 19 providing a smooth transition between the peripheral surface 18 and the base end 4.

[0059] The second retention element 7b also comprises a peripheral surface 18, preferably having the same diameter as the peripheral surface 18 of the first retention element 7a. Facing the base end 4, the second retention element 7b comprises a first flank 20 which comprises a chamfered surface portion facing the base end 4. The angle of the chamfer preferably is in a range between 15° and 60° with respect to the longitudinal axis, allowing the retention element 7b to be deflected and/or deformed radially inwards when pushing the spring element 1 into the mounting cap. The first retention element 7a is also able to deflect and/or deform radially inwards by virtue of the transition radius 19.

[0060] Both retention elements 7a, b comprise a second flank 21 facing away from the base end 4. In the embodiment shown, the second 21 flank is oriented perpendicular to the longitudinal axis, i.e. parallel to a radial line towards the longitudinal axis L (cf. FIGS. 1, 2).

[0061] Alternatively, it would be within the scope of invention to have the second flank 21 formed as an undercut.

[0062] The second retention element 7b comprises a transition radius 19 in between the first flank 20 and the peripheral surface 18. Further preferably, both retention elements 7a, b also comprise a transition radius from the peripheral surface 18 to the second flank 21.

[0063] The first retention element 7a and the second retention element 7b are spaced apart in the axial direction by a cylindrical wall section 17a. Relative to the peripheral surfaces 18 of the retention elements 7a, 7b which are formed as projections from the base body 3, the surface portion 17a defines a recess. Facing away from the second flank 21 of the second retention element, the base body 3 comprises a further cylindrical portion 17b, which, again relative to the peripheral surfaces 18 of the retention elements 7a, 7b is formed as a recess.

[0064] The function of recesses 17a, 17b is to provide space for corresponding protrusions formed on a mounting cap so that the mounting cap and the spring element 1 can enter a positive engagement (cf. FIGS. 4a-c). The surface portions 17a, 17b in the shown embodiment comprise a cylindrical surface portion, but need not necessarily be cylindrical as far as the invention is concerned. The surface portions 17a, b might in fact also include non-cylindrical surface portions or might be entirely non-cylindrical, i.e. convex, concave or conical, or be formed as a combination of several of these shapes. Their key function, which will be contemplated in the context of FIGS. 4a-c, is providing the volume necessary for the interengagement of the corresponding retention elements 7a,b of the spring element 1 on the one hand side and the mounting cap on the other hand side.

[0065] While the FIGS. 1-3 mainly show the spring element 1 and details thereof in isolation, FIGS. 4a-c illustrate the inventive use of the spring element 1 of FIGS. 1-3 in a jounce bumper assembly 100. The jounce bumper assembly 100 comprises the spring element 1 mounted into a mounting cap 50 as shown in FIG. 4a. The mounting cap 50 preferably is made partially or completely of a polymer, such as a thermoplastic material, for example polyoxymethylene (POM), or partially of completely made of metal. The outer contour of the mounting cap 50, which preferably acts as a spacer between the vehicle structure (not shown) and the spring element 1 may be substantially cylindrical or may be oblong, depending on the space constraints of the mounting environment of the jounce bumper assembly 100.

[0066] A cross sectional view through the jounce bumper assembly of FIGS. 4a, 4b is shown in FIG. 4c. From FIG. 4c it is apparent that in addition to the mounting cap 50 and the spring element 1, the jounce bumper assembly 100 also comprises a sleeve insert 52 that is added to the mounting cap 50 for installation purposes.

[0067] The mounting cap 50 comprises a first annular recess 51a and, spaced apart therefrom, a second annular recess 51b. The recesses 51a, b are configured to receive the first and second retention elements 7a, b of the spring element 1.

[0068] Likewise, the mounting cap 50 comprises a number of protrusions having a contact flank 53, respectively. The protrusions and contact flanks 53 are spaced apart from one another in the direction of the longitudinal axis L such that the retention elements 7a, 7b fit into the mounting cap 50, and such that the surface portions 17a, 17b adjacent to the retention elements 7a, 7b accommodate the protrusions having the contact flanks 53, and allow for a snug fit of the correspondingly shaped retention elements in the (shown) mounted state. The volume of the recesses 51a, b preferably is minimally smaller, at least in the axial direction (direction of the longitudinal axis L), as compared to the axial extension of the retention elements 7a, 7b, thus requiring a predetermined amount of compression of the retention elements 7a, 7b to ensure the proper fit inside the mounting cap 50.

[0069] While the embodiment shown in FIGS. 1-4c, for ease of understanding, only shows a jounce bumper assembly and spring element having exactly two retention elements spaced apart from one another in the direction of the longitudinal axis, the invention contemplates that also a higher number of retention elements may be present of the spring element and correspondingly on the mounting cap, with each retention element being spaced apart from other retention elements in the direction of the longitudinal axis L.

[0070] Also, while the figures only show the use of one-piece retention elements that extend along the entire circumference of the base body, respectively, it is within the invention that at least one, preferably each, retention element is composed of a plurality of segments that are spaced apart from one another in the circumferential direction, wherein the segments of one retention element are axially spaced apart from a second retention element, or a plurality of segments, for that matter.