Wheel hub with centering device

Abstract

A wheel hub (1) having a radially extending wheel flange (17) which has fastening holes (3), having a cylindrical projection which extends from the wheel flange (17) axially on the vehicle side and which serves for at least partially receiving a rolling bearing, and having a centering device which is mounted axially on the wheel side. A high rigidity of the wheel hub (1) and/or of the wheel bearing unit is realized with little material usage. One possibility arises by the centering device of a wheel hub being regarded as the product of the compromise between rigidity and possible material removal. In this regard, a particular arrangement of the webs that form the centering device is provided which leads to a particularly advantageous solution, specifically by virtue of the webs (7) being oriented in the same radial direction (A, B) as the fastening holes (3) of the wheel flange (17).

Claims

1. A wheel hub comprising: a wheel flange that extends in a radial direction and has fastening holes, a cylindrical projection extending in an axial direction on a vehicle side from the wheel flange for at least partial holding of a rolling contact bearing, and a centering device formed integrally with the wheel flange is arranged on a wheel side in the axial direction and is arranged concentric to a rotational axis (R) of the wheel hub for holding a wheel rim or brake disk, the centering device is formed from connecting pieces that are separated from each other in a peripheral direction by recesses, and the wheel flange includes a varying outer diameter, the wheel flange includes a first plurality of radially extending portions that include the fastening holes, the first plurality of radially extending portions define a first outer diameter, and the wheel flange includes a second plurality of radially extending portions each spaced between respective pairs of the first plurality of radially extending portions, the second plurality of radially extending portions define a second outer diameter that is less than the first outer diameter.

2. The wheel hub according to claim 1, wherein in a first radial direction (A) of a first one of the fastening holes of the wheel flange, a first one of the connecting pieces is arranged and in a second radial direction (B) a second one of the connecting pieces is arranged.

3. The wheel hub according to claim 2, wherein the first and the second connecting pieces cover, in a plane of an axial contact surface of the wheel flange or a plane parallel thereto, a first opening angle (a) that is defined by a diameter of the fastening hole associated with each of the connecting pieces.

4. The wheel hub according to claim 3, wherein adjacent hole receptacles of the wheel flange span an equal angle, in the plane of the axial contact surface.

5. The wheel hub according to claim 2, wherein the first and second connecting pieces cover, in a plane of an axial contact surface of the wheel flange or a plane parallel thereto, a second opening angle (13) that is defined by a width of a hole receptacle in a peripheral direction.

6. The wheel hub according to claim 1, wherein the connecting pieces are arranged in the fastening holes of the wheel flange in the radial direction with respect to the rotational axis (R).

7. The wheel hub according to claim 1, wherein a number of the connecting pieces is equal to a number of the fastening holes of the wheel flange or forms a whole-number multiple and several of the connecting pieces are allocated to one of the fastening holes.

8. The wheel hub according to claim 7, wherein, for a plurality of the fastening holes of the wheel flange, one of the connecting pieces is allocated to one of the fastening holes, and said connecting piece is arranged in the same radial direction (a) as the associated fastening hole.

9. The wheel hub according to claim 1, wherein at least one recess forms a rounded section between two adjacent connecting pieces or a base of the recess is arranged in a plane of an axial contact surface of the wheel flange or parallel to said plane.

10. A wheel bearing unit comprising a wheel hub according to claim 1.

11. The wheel hub according to claim 1, wherein one of the second plurality of radially extending portions includes a through hole, and the through hole is radially offset from the fastening holes.

12. The wheel hub according to claim 1, wherein the wheel flange is star-shaped.

13. The wheel hub according to claim 1, wherein the varying outer diameter of the wheel flange is partially defined by alternating radially concave portions and radially convex portions.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Shown are:

(2) FIG. 1 a wheel bearing unit with a wheel hub with five fastening holes and the associated connecting pieces of the centering device,

(3) FIG. 2 the wheel hub from FIG. 1,

(4) FIG. 3 the wheel hub from FIG. 1 in a sectioned view,

(5) FIG. 4 the wheel bearing unit from FIG. 1 in a sectioned view, and

(6) FIG. 5 the wheel bearing unit from FIG. 1 with opening angles of the connecting pieces and recesses in the centering device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(7) FIG. 1 shows a wheel bearing unit 2 with a star-shaped wheel hub, a centering device with 5 connecting pieces 7, and the recesses 8 lying in-between, and a roller bearing mounted on the wheel hub.

(8) The wheel bearing unit 2 can be bolted on a wheel carrier with the use of the fastening hole 14 on the outer ring 13 of the wheel bearing unit 2. Here, the position of the wheel flange 17 is not important, because the intermediate spaces in the circumferential direction between the fastening holes 3 of the wheel flange 17 are designed with such little material that a bolt can be bolted into a fastening hole 14 nearly independently from the position of the wheel flange 17.

(9) The connecting pieces 7 each lie between a fastening hole 3 of the wheel flange 17 and the rotational axis R. The connecting pieces 7 raise in the axial direction above the axial contact surface 15 of the wheel flange 17, but lie in the radial direction in the same direction as also the associated fastening holes 3. This is indicated, for example, with the radial direction A that is shown schematically as an arrow in FIG. 1. The connecting pieces 7 are arranged in the radial direction essentially in the center between the rotational axis R and the associated fastening hole 3.

(10) The connecting pieces form a cylindrical centering device; they are separated from each other in the circumferential direction by round holes that are oriented in the radial direction and open in the axial direction. In this embodiment, the round holes form the recesses 8.

(11) Otherwise, the recesses 8 could also assume other shapes. For example, the base of the recesses 8 could lie in the surface of the axial contact surface 15 and the flanks of the connecting pieces oriented in the circumferential direction could be parallel to each other, wherein a rectangular recess 8 would be created that is easy to produce, but has lower stiffness than the solution shown in the figures. Alternatively, the recesses could also have a V-shape in which together the flanks form an angle that is open in the axial direction. The latter embodiment is especially simple to produce.

(12) The axial length of the connecting pieces 7 is not significant, with an equal height for all connecting pieces 7 being the simplest to handle.

(13) The wheel flange 17 is defined in its radial outer area by different radii. These radii can be equal in magnitude, but to that effect consider that parts 18 are oriented both convexly and also concavely outward in the radial direction. The parts 18 are delimited from each other by separating lines 19 and make the shaping of the star-shaped wheel flange 17 especially simple.

(14) The hole receptacles 6 surround the fastening holes 3 in the radial direction and are formed by two successive convex parts 18. In the rest of the outer area of the wheel flange 17, convex and concave parts 18 alternate. In this way, an intermediate raised section 5 that contributes overall to the stiffness of the wheel bearing flange 17 is formed between two adjacent fastening holes 3.

(15) In one of the intermediate raised sections 5 there is a hole 4 that is provided for the fastening of a brake disk.

(16) FIG. 2 shows the wheel hub 1 of the wheel bearing unit 2 from FIG. 1. The connecting piece 7 can cover, in one special embodiment, the first opening angle that is defined by the two legs that have their origin at the rotational axis R and are tangent to the fastening hole 3 of the wheel flange 17 in a plane of rotation. The shown connecting piece 7 surpasses this first opening angle by far, so that the wheel hub 1 indeed has a higher weight, but better stiffness. Even the second opening angle is covered by the connecting pieces 7, wherein the second opening angle is defined by the arc measure of the hole receptacle 6. For lower weight wheel hubs, the connecting pieces 7 can be reduced so that their arc measure corresponds either to the first or the second opening angle , or lies between these two angles.

(17) FIG. 3 shows the wheel hub 1 from FIG. 2 in a sectioned view, wherein the roller rivet collar 9 can be seen that can hold the inner ring 11 (see FIG. 4) and can pretension the roller bearing.

(18) The wheel hub 1 further forms a roller body raceway 10 that forms part of the roller bearing on the cylindrical projection extending from the wheel flange in the axial direction on the vehicle side.

(19) In FIG. 3, with reference to the section through the fastening hole 3, it can be seen that the connecting piece 7 is arranged in the radial direction A with respect to the rotational axis R, exactly like the cut fastening hole 3.

(20) FIG. 4 shows a sectioned view of the wheel bearing unit 2 that is constructed as an angular contact ball bearing unit and has two roller body rows 12 that are pre-tensioned by means of the inner ring 11 and outer ring 13 relative to the wheel hub 1 such that these can be bolted on a not-shown wheel carrier by means of the fastening holes 14, without performing a pretensioning or pretensioning correction of the roller bearing.

(21) FIG. 5 emphasizes a special combination of an opening angle for connecting pieces and recesses. The wheel hub has a centering device that has a height h of 10 millimeters and is formed by five connecting pieces and five recesses, wherein the opening angle that can be allocated to the connecting pieces 7 equals 40 degrees and the opening angle that can be allocated to the recesses equals 32 degrees. This embodiment has proven itself to be a practical solution.

(22) In the shown embodiments, the number of recesses 8 in the rim seat area of the wheel hub 1 corresponds to the number of fastening holes 3 on the wheel flange 17. This, however, is not necessarily the case, just as many intermediate connecting pieces could be provided that could be allocated to no fastening hole. In this way, an increased component stiffness of the wheel hub is similarly achievable.

(23) In summary, the invention relates to a wheel hub with a wheel flange extending in the radial direction and having fastening holes, with a cylindrical projection extending from the wheel flange on the vehicle side in the axial direction for at least partial holding of a roller bearing and with a centering device formed on the wheel side in the axial direction. The declared goal of the invention is to achieve a high stiffness of the wheel hub or the wheel bearing unit with low use of materials. One possibility is created in that the centering device of a wheel hub is identified as the object for compromise between stiffness and possible material recesses. For this purpose, a special arrangement of the connecting pieces forming the centering device is proposed, leading to an especially advantageous solution, namely, in that the connecting pieces are oriented in the same radial direction and also the fastening holes of the wheel flange.

LIST OF REFERENCE NUMBERS

(24) A First radial direction of a fastening hole of the wheel flange B Second radial direction of another fastening hole of the wheel flange D Diameter of the fastening hole h Axial height of the centering device R Rotational axis First opening angle Second opening angle Opening angle of the recesses Opening angle of the connecting pieces 1 Wheel hub 2 Wheel bearing unit 3 Fastening hole 4 Brake disk fastening hole 5 Intermediate raised section 6 Hole receptacles 7 Connecting piece 8 Recess 9 Rolling contact rivet collar 10 Raceway of the rolling bodies 11 Inner ring 12 Roller body 13 Outer ring 14 Fastening hole of the fastening flank 15 Axial contact surface 16 Cylindrical projection 17 Wheel flange 18 Rounded part 19 Partition line