Mounting arrangement of a support spring for a strut

Abstract

A receiving arrangement (1) of a lower end of a spring (10) on a damper tube (11) of a shock absorber of a strut, wherein the receiving arrangement (1) has a bearing unit (12) by means of which a rotation of the damper tube (11) relative to the spring (10) about a longitudinal axis (13) of the strut is enabled, characterized in that the bearing unit (12) has an upper bearing ring (14) and a lower bearing ring (15), which bearing rings (14, 15) are designed to slide against each other between the spring (10) and the damper tube (11) by forming an axial bearing (18) and a radial bearing (19), wherein a spring receptacle (16) is provided on which the lower end of the spring (10) rests, and wherein the upper bearing ring (14) is arranged on the spring receptacle (16) in a rotationally fixed manner, and wherein a support ring (17) is provided which rests on the damper tube (11) sits on, wherein the lower bearing ring (15) is arranged on the support ring (17) in a rotationally fixed manner.

Description

[0001] The present invention relates to a receiving arrangement of a lower end of a suspension spring on a damper tube of a vibration damper of a spring strut, in particular for a vehicle, wherein the receiving arrangement has a bearing unit by means of which a rotation of the damper tube relative to the suspension spring about a longitudinal axis of the spring strut is possible. STATE OF THE ART

[0002] Typically, a so-called strut mount is located on the upper side of the suspension spring, so that its lower end is supported on the damper tube in a torsion-proof manner, and the suspension spring can rotate relative to the vehicle body via the upper strut mount. However, this complicates the upper structure of the strut.

[0003] By way of example, EP 2 128 464 B1 shows a strut mount for rotatably supporting a suspension spring at the upper end of the suspension strut. The strut mount is based on plain bearing elements for radial and axial support of the suspension spring. DE 10 2009 011 669 A1 also discloses a suspension strut with a shock absorber and a suspension spring. JP 2002 - 139 087 A discloses a buffer with an axial bearing. DE 10 2008 057 590 A1 discloses a plain bearing for a suspension strut. DE 10 2009 014 986 A1 describes a ring bearing with an axial bearing. DE 696 27 116 T2 also discloses a suspension strut with a shock absorber and a suspension spring. US 4 817 928 A discloses a shock absorber with a spring strut inclined relative to the spring strut.

[0004] KR 20 1997 0 041 738 U discloses a receiving arrangement for a lower end of a suspension spring on a damper tube of a vibration damper of a spring strut that can be used for a vehicle. The receiving arrangement has a bearing unit with rolling elements, by means of which rotation of the damper tube relative to the suspension spring about a longitudinal axis of the spring strut is possible. The rolling bearing serves to absorb axial forces and is designed with a very large diameter to prevent tilting of the suspension spring. Safe operation of the receiving arrangement for the suspension spring on the damper tube is not generally guaranteed, especially when the spring strut is relieved of load. Furthermore, with greater spring compression of the spring strut, tilting moments can arise in the suspension spring, which likewise cannot be absorbed by the axial bearing without an additional radial bearing component. OBJECT OF THE INVENTION

[0005] The object of the invention is to further develop a mounting arrangement for the lower end of a suspension spring on a damper tube of a vibration damper of a strut, which enables improved support of the suspension spring on the damper tube. Furthermore, the object of the invention is to make the mounting arrangement compact and as simple and cost-effective as possible.

[0006] This object is achieved by a mounting arrangement according to the preamble of claim 1 and by a spring strut according to the preamble of claim 7 with the respective characterizing features. Advantageous developments of the invention are specified in the dependent claims.

[0007] The invention includes the technical teaching that the bearing unit comprises an upper bearing ring and a lower bearing ring, which bearing rings are designed to slide on one another to form an axial bearing and a radial bearing between the suspension spring and the damper tube. Furthermore, the support ring has a radial support section that extends between the upper bearing ring and the damper tube and on which the upright leg of the cross-sectional profile of the lower bearing ring is supported radially inward to form the radial bearing.

[0008] The core of the invention is the design of the bearing unit as a plain bearing unit with an axial bearing to support axial forces along the longitudinal axis of the strut and a radial bearing to support forces acting perpendicular to the longitudinal axis. The plain bearing unit can be designed simply and compactly and allows the damper tube to rotate relative to the suspension spring. A piston assembly with a piston rod within the damper tube can also be mounted in a rotationally fixed manner with the suspension spring at the upper end of the strut, allowing the damper tube connected to the steering knuckle to rotate within the plain bearing unit.The ability of the damper tube to rotate relative to the vehicle body is particularly important on the front axle of a motor vehicle during steering angles. If the suspension spring can be rigidly connected to the vehicle body with the upper connection end of the strut, this simplifies the design of the upper end of the strut. Overall, the plain bearing unit between the suspension spring and the damper tube can be designed more simply than a bearing unit between the suspension spring and the upper end of the strut, for example a strut plate. The particular advantage is that the bearing unit designed as a plain bearing unit with a radial and an axial bearing component can have a diameter that is only slightly larger than the diameter of the damper tube.Furthermore, a plain bearing unit can be easily constructed from a number of ring elements that are guided over the damper tube until the suspension spring can finally be placed on the bearing unit.

[0009] A smaller bearing diameter, which is made possible in particular by choosing a plain bearing, results in lower frictional torques, which presents another advantage. The inherent disadvantage of plain bearings, which are characterized by high friction, high breakaway forces, and thus poor steering feedback in McPherson applications, is significantly compensated for by the design with its overall small radii. The effective lever arm of the relevant frictional forces is thus reduced to a minimum and kept small.

[0010] A spring retainer is provided on which the lower end of the suspension spring rests, and the upper bearing ring is mounted on the spring retainer in a rotationally fixed manner. The spring retainer, designed as a single part, allows for the choice of an alternative material compared to the upper bearing ring. In particular, it is advantageous if the spring retainer is designed as a soft component, which, due to its elastic compliance properties, provides noise dampening.

[0011] Furthermore, a support ring is provided which sits on the damper tube and wherein the lower bearing ring is arranged on the support ring in a rotationally fixed manner. It is particularly advantageous for the lower bearing ring to be made of a material that differs from the material of the support ring. The support ring can, for example, comprise a steel material, while the lower bearing ring can comprise a non-ferrous metal. In particular, the damper tube can have a support shoulder against which the support ring sits to absorb axial forces in the longitudinal axis direction. The support ring can be pressed onto the damper tube or, alternatively or additionally, the support ring can be materially connected to the damper tube. In particular, it must be ensured that the support ring, and with it the lower bearing ring, cannot rotate on the damper tube.

[0012] Furthermore, the connection between the lower bearing ring and the support ring is designed in such a way that the lower bearing ring cannot rotate on the support ring. For example, the lower bearing ring is glued to the support ring or connected to it in some other form-fitting and / or material-fitting manner.

[0013] According to an advantageous development of the mounting arrangement, the lower bearing ring is designed as a shoulder plain bearing and has an L-shaped cross-sectional profile, with a horizontal base leg of the cross-sectional profile forming the axial bearing and a vertical leg of the cross-sectional profile forming the radial bearing. This has the advantage that both the axial bearing and the radial bearing can be formed with just one one-piece lower bearing ring. Further advantages arise from the mounting of the lower bearing ring on the support ring. The upper bearing ring can be adapted to the L-shaped contour of the lower bearing ring, so that the complementary bearing counterpart on the upper bearing ring also forms the axial bearing and the radial bearing. The upper bearing ring is in particular also designed as a one-piece. Another advantage is that the materials of the upper bearing ring and the lower bearing ring differ from one another.

[0014] A further advantage is achieved if the upper bearing ring forms a sliding seal against the outside of the damper tube. For this purpose, the upper bearing ring can have a coating, a seal seat or the like on the inside, and the sliding seal of the upper bearing ring against the outside of the damper tube prevents contaminants from entering the bearing gap between the two bearing rings. Another advantage is that a labyrinth seal is formed between the upper bearing ring and the support ring on the outside of the arrangement of the lower bearing ring. This means that the lower bearing ring and thus the axial bearing and the radial bearing are enclosed between two seals, one formed on the outside by the labyrinth seal and the other formed on the inside by the sliding seal of the upper bearing ring against the damper tube.

[0015] Furthermore, it is advantageous if the support ring has a radial support section that extends between the upper bearing ring and the damper tube, and on which the upright leg of the cross-sectional profile of the lower bearing ring is supported radially inward to form the radial bearing. This results in a design variant of the radial bearing, and the lower bearing ring, with its L-shape, does not have to reach all the way to the damper tube. Instead, it is possible to design the support ring with the radial support section, so that the lower bearing ring can rest on the outer surface of the support section with the upright leg, and the lower bearing ring rests with the base leg on a circumferential flat surface of the support ring.Overall, this results in a simple design of the bearing unit as a plain bearing with an axial and a radial bearing component. Before assembly, the upper bearing ring can already be connected to the spring retainer, and the lower bearing ring can already be connected to the support ring. During assembly, the support ring and the lower bearing ring are placed on the damper tube, and then, to form the bearing unit, the spring retainer and the upper bearing ring are pushed onto the damper tube until the bearing unit is fully formed.

[0016] The invention further relates to a suspension strut for a vehicle with a receiving arrangement for a lower end of a suspension spring on a damper tube of the suspension strut, wherein the receiving arrangement comprises a bearing unit by means of which rotation of the damper tube relative to the suspension spring about a longitudinal axis of the suspension strut is enabled. According to the invention, the bearing unit comprises an upper bearing ring and a lower bearing ring, which bearing rings are designed to slide on one another, forming an axial bearing and a radial bearing between the suspension spring and the damper tube. The further features and associated advantages of the receiving arrangement are also taken into account for the suspension strut according to the invention. PREFERRED EMBODIMENT OF THE INVENTION

[0017] Further measures improving the invention are described in more detail below, together with the description of a preferred embodiment of the invention, with reference to the figures. It shows: Fig. 1 a view of a receiving arrangement of a suspension spring on a damper tube according to a first embodiment and Fig. 2 a view of a receiving arrangement of a suspension spring on a damper tube according to a second, simplified embodiment.

[0018] The Fig. Figure 1 shows a half-side view of a receiving assembly 1 for a lower end of a suspension spring 10 on a damper tube 11 of a vibration damper of a spring strut, which can be used, for example, in the chassis of a vehicle. The receiving assembly 1 has a bearing unit 12, by means of which rotation of the damper tube 11 relative to the suspension spring 10 about a longitudinal axis 13 of the spring strut is possible. The longitudinal axis 13 forms the axis of symmetry of the damper tube 11 and essentially also the axis of symmetry of the bearing unit 12.

[0019] The bearing unit 12 has an upper bearing ring 14 and a lower bearing ring 15, which slide on each other when the suspension spring 10 rotates relative to the damper tube 11 about the longitudinal axis 13. The upper bearing ring 14 has a base leg to form an axial bearing 18 and a standing leg to form a radial bearing 19. The upper bearing ring 14 is adapted to a groove-like, inner contour of a support ring 17, which, with an inner surface, forms the counterpart of the radial bearing 19. The lower bearing ring 15 forms the counterpart of the axial bearing 18 and is thus located below the base leg.

[0020] The upper bearing ring 14 is arranged in a rotationally fixed manner on an intermediate ring 23. Above the intermediate ring 23 is a receiving ring 24 on which a spring retainer 16 sits. The suspension spring 10 is supported on the spring retainer 16. The spring retainer 16 is made of a soft component, and the receiving ring 24 is made of a damping plastic material, providing vibration-damping and noise-damping properties for the bearing unit 12. Therefore, the materials of the upper bearing ring 14 and the spring retainer 16, as well as the intermediate ring 23 and the receiving ring 24, differ from one another.

[0021] The lower bearing ring 15 is disk-shaped and secured to the support ring 17 in a rotationally fixed manner. The lower bearing ring 15 is formed, for example, by a steel disk. The support ring 17 sits on a support shoulder 22 of the damper tube 11, creating a positive fit along the longitudinal axis, and axial forces of the suspension spring 10 are securely transmitted to the damper tube 11 via the support ring 17. A molded portion 25 is shown in the damper tube 11 as an example, preventing rotation of the support ring 17 on the damper tube 11. The molded portion 25 may be formed multiple times around the circumference of the damper tube 11.

[0022] A labyrinth seal 20 is formed between a downwardly facing wraparound formed on the intermediate ring 23 and an outer region of the support ring 17, by which the penetration of moisture and contaminants is prevented, at the same time the escape of lubricant from the bearing area of ​​the axial bearing 18 and the radial bearing 19 can be prevented.

[0023] Fig.Figure 2 shows a detailed embodiment of a support assembly 1 with a bearing unit 12, which is designed according to the invention as a plain bearing unit and has an axial bearing 18 and a radial bearing 19. The axial bearing 18 and the radial bearing 19 are formed by a one-piece lower bearing ring 15, which is seated in the support ring 17. The complementarily designed upper bearing ring 14 is connected to a spring receptacle 16, against which the suspension spring 10 is supported. Also shown is a support shoulder 22 in the damper tube 11, on which the support ring 17 rests in a form-fitting manner.

[0024] The upper bearing ring 14 and the support ring 17 form a labyrinth seal 20 on the outside surrounding the lower bearing ring 15, which prevents the penetration of contaminants and moisture into the gap between the upper bearing ring 14 and the lower bearing ring 15. On the inside, the upper bearing ring 14 is designed to seal against the outside of the damper tube 11 in a manner not shown in detail, for example by means of a coating or the like, such that despite the seal, the rotatability of the upper bearing ring 14 on the damper tube 11 is maintained. This also prevents the penetration of contaminants between the upper bearing ring 14 and the damper tube 11 into the sliding gap between the bearing rings 14 and 15.

[0025] The support ring 17 has a radial support section 21 that extends between the upper bearing ring 14 and the damper tube 11 and on which the standing leg of the cross-sectional profile of the lower bearing ring is supported inwardly to form the radial bearing 19. The material of the support ring 17 differs from the material of the lower bearing ring 15, and the lower bearing ring 15 is, for example, pressed and / or glued into the pocket-like, circumferential recess in the support ring 17. For example, the upper bearing ring 14 forms a plastic component, and the lower bearing ring forms a metallic component based on a non-ferrous alloy.

[0026] All features and / or advantages arising from the claims, the description or the drawings, including structural details or spatial arrangements, may be essential to the invention both individually and in a wide variety of combinations. List of reference symbols 1 Recording arrangement 10 suspension spring 11 Damper tube 12 storage units 13 Longitudinal axis 14 upper bearing ring 15 lower bearing ring 16 Spring holder 17 Support ring 18 thrust bearings 19 radial bearings 20 Labyrinth seal 21 radial support section 22 Support shoulder 23 intermediate ring 24 mounting ring 25 Molding

Claims

[1] Receiving arrangement (1) of a lower end of a suspension spring (10) on a damper tube (11) of a vibration damper of a spring strut, wherein the receiving arrangement (1) has a bearing unit (12) by means of which a rotation of the damper tube (11) relative to the suspension spring (10) about a longitudinal axis (13) of the spring strut is possible, characterized by in that the bearing unit (12) has an upper bearing ring (14) and a lower bearing ring (15), which bearing rings (14, 15) are designed to slide on one another to form an axial bearing (18) and a radial bearing (19) between the support spring (10) and the damper tube (11), wherein a spring receptacle (16) is provided, on which the lower end of the support spring (10) sits, and wherein the upper bearing ring (14) is arranged on the spring receptacle (16) in a rotationally fixed manner, and wherein a support ring (17) is provided which sits on the damper tube (11), and wherein the lower bearing ring (15) is arranged on the support ring (17) in a rotationally fixed manner. [2] Recording arrangement (1) according to claim 1, characterized by that the lower bearing ring (15) is designed as a shoulder plain bearing and has an L-shaped cross-sectional profile, wherein a horizontal base leg of the cross-sectional profile forms the axial bearing (18) and wherein a vertical leg of the cross-sectional profile forms the radial bearing (19). [3] Receiving arrangement (1) according to one of the preceding claims, characterized by that the upper bearing ring (14) forms a sliding seal against the outside of the damper tube (11). [4] Receiving arrangement (1) according to one of the preceding claims, characterized by that a labyrinth seal (20) is formed between the upper bearing ring (14) and the support ring (17) on the outside for arranging the lower bearing ring (15). [5] Receiving arrangement (1) according to one of the preceding claims, characterized bythat the spring holder (16) is designed as a soft component which, due to its elastic compliance properties, effects noise damping. [6] Receiving arrangement (1) according to one of the preceding claims, characterized by that the support ring (17) has a radial support section (21) which extends between the upper bearing ring (14) and the damper tube (11) and on which the standing leg of the cross-sectional profile of the lower bearing ring (15) is supported radially inwards to form the radial bearing (19). [7] Suspension strut for a vehicle with a receiving arrangement (1) of a lower end of a suspension spring (10) on a damper tube (11) of the suspension strut, wherein the receiving arrangement (1) has a bearing unit (12) by means of which a rotation of the damper tube (11) relative to the suspension spring (10) about a longitudinal axis (13) of the suspension strut is possible, characterized byin that the bearing unit (12) has an upper bearing ring (14) and a lower bearing ring (15), which bearing rings (14, 15) are designed to slide on one another to form an axial bearing (18) and a radial bearing (19) between the support spring (10) and the damper tube (11), wherein a spring receptacle (16) is provided, on which the lower end of the support spring (10) sits, and wherein the upper bearing ring (14) is arranged on the spring receptacle (16) in a rotationally fixed manner, and wherein a support ring (17) is provided which sits on the damper tube (11), and wherein the lower bearing ring (15) is arranged on the support ring (17) in a rotationally fixed manner. [8] Suspension strut according to claim 7 with a receiving arrangement (1) according to one of claims 2 to 6.

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