EP2084412A1

EP2084412A1 - Wheel bearing arrangement for motor vehicles

Info

Publication number: EP2084412A1
Application number: EP07821319A
Authority: EP
Inventors: Horst DÖPPLING; Heinrich Hofmann; Rainer Eidloth; Robert Plank; Ludwig Winkelmann
Original assignee: Schaeffler KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2006-11-02
Filing date: 2007-10-15
Publication date: 2009-08-05
Also published as: JP2010508490A; WO2008052875A1; US20100247019A1; CN101542144A; DE102006051644A1

Abstract

The invention relates to a wheel bearing arrangement for motor vehicles, composed substantially of a multi-row angular-contact rolling bearing (1) which has an inner bearing ring (4, 4a), which is arranged on or at least partially integrated into a hub (2) of a wheel-side fastening flange (3), and an outer bearing ring (7), which is arranged on or at least partially integrated into a hub (5) of a vehicle-side fastening flange (6) coaxially with respect to said inner bearing ring (4, 4a), and having a multiplicity of rolling bodies (12) which are arranged in a plurality of rows (8, 9, 10, 11) adjacent to one another between said bearing rings (4, 4a, 5) and which roll, on oblique defined pressure angle axes (13, 14, 15, 16), in groove-shaped raceways (17, 18, 19, 20 and 21, 22, 23, 24) in the two bearing rings (4, 4a, 5) and which are held at uniform intervals with respect to one another in the peripheral direction by means of a plurality of bearing cages (25, 26, 27, 28). According to the invention, all the rolling bodies (12) of the angular-contact rolling bearing (1) are embodied as ball rollers with in each case two side faces which are flattened symmetrically from a spherical basic shape and which are arranged parallel to one another and between which said ball rollers have a width which is reduced by 20% to 30% in relation to the diameter of their spherical basic shape.

Description

Name of the invention

Wheel bearing for motor vehicles

description

Field of the invention

The invention relates to a wheel bearing for motor vehicles according to the preamble-forming features of claim 1, and it is particularly advantageously applicable to driven and non-driven or to steerable and non-steerable wheels of motor vehicles.

Background of the invention

Wheel bearings are highly stressed parts that have to withstand the various operating stresses that occur during driving in any case. In motor vehicles, one differentiates between driven and non-driven wheels, which in turn are subdivided into steerable or non-steerable wheels. Basically, it applies to all wheels that they have to be guided for technical reasons as accurate and backlash-free as possible and therefore require a high-carrying, rigid storage. This is achieved in passenger vehicles predominantly with O-arrangement against each other employed double-row angular contact ball bearings, while in commercial vehicles because of the higher load ratings especially two single-row, in O arrangement against each other employees or double-row tapered roller bearings are used. In addition, however, it is also known, driven or non-driven wheels of passenger vehicles to increase the carrying capacity and the tilting stiffness of the wheel bearing on multi-row skew bearings Ia like, as they are generic to DE 103 31 936 A1, for example, known from DE. This wheel bearing is essentially formed by a four-row angular contact ball bearing which has a two-part inner bearing ring arranged on a hub of a wheel-side fastening flange and a coaxial with this arranged in a hub of a vehicle-side mounting flange or integrated in this one-piece outer bearing ring and is formed with a plurality in four rows next to each other between these bearing rings bearing balls, wherein the pitch diameter of the two axially inner rows smaller than the pitch circle diameter of the two axially outer Rows is. The bearing balls roll on obliquely set defined pressure angle axes in groove-shaped raceways in both bearing rings and are held by two bearing cages, each receiving an inner and an outer row of bearing balls in the circumferential direction at regular intervals to each other.

However, it has proven to be disadvantageous in these wheel bearings formed by four-row angular contact ball bearings that they likewise quickly reach their performance limits with regard to the bearing capacity and rigidity of the bearing and thus the desired service life extension is not sufficient in many applications. This is due to the fact that although there is sufficient radial space in most of the wheel bearings to increase the bearing capacity and rigidity of such an angular contact ball bearing through the use of bearing balls with larger diameters, but the associated simultaneously increase the axial space of the angular contact ball bearing in the many cases by the surrounding construction of the wheel bearing immutable limits are set. Despite the thus essentially constant installation space for the wheel bearing, however, automobile manufacturers are placing ever-increasing demands on the wheel bearings used with regard to their carrying capacity, rigidity and service life.

Object of the invention

Based on the stated disadvantages of the known state of the art, the invention is therefore the object of a compact building

Wheel bearing for motor vehicles to design, as a multi-row

Skew bearings designed wheel bearing without changing the Umgege- construction design characterized by a significant increase in the load capacity and rigidity and thus has a longer life.

Description of the invention

According to the invention this object is achieved in a wheel bearing according to the preamble of claim 1 such that all rolling elements of the angular contact bearing used as ball rollers with two symmetrically flattened from a spherical base and parallel side surfaces are formed, between which these compared to the diameter of their ball base have a reduced by 20% to 30% width.

The invention is thus based on the finding that it is possible by the use of ball rollers as rolling elements for the multi-row angular contact bearings of the wheel bearing to use compared to conventional bearing balls in diameter significantly enlarged rolling elements to significantly increase the carrying capacity and rigidity of the angular rolling bearing, said laterally flattened and thus narrow design of the rolling elements no additional axial space for such a tapered roller bearing is necessary.

Preferred embodiments and further developments of the inventively designed wheel bearing are described in the subclaims.

Thereafter, it is provided according to claims 2 and 3 in the present invention formed wheel bearing, that the angular roller bearing preferably four rows of trained as ball rolling elements, of which the preferably identical pitch circle diameter of the two axially inner rows smaller than the likewise preferably identical pitch circle diameter two axially outer rows is formed. In addition, while the diameter of the ball base of the rolling elements of the two axially outer rows opposite the diameter of the rolling elements of the two axially inner rows is larger, so that in each case an axially outer row and the adjacent axially inner row of rolling elements having a first and a second row pair each form different Wälzkörper- and pitch circle diameters. However, it would also be possible to form the ball rollers of all rows with the same diameter of the ball basic shape at different pitch diameters between the axially inner and the axially outer rows of rolling elements. It would also be conceivable additionally to form the ball rollers on the wheel sections of their running surfaces with an outgoing logarithmic profile in order to counteract edge stresses occurring between the ball rollers and their raceways in the bearing rings.

Based on the above-described embodiment, the inventively designed Schrägwälzlager according to claims 4 and 5 also characterized by the fact that the Druckwinkelachsen each pair of rolling elements either diverging or converging or parallel to each other to the longitudinal central axis of the angular contact bearing running arranged and both pairs of rows of rolling elements axially mirror images or in O-arrangement against each other are employed. When arranging the two pairs of rows on each diverging or converging pressure angle axes, it has proven to be advantageous to perform each row of rolling elements in separate, preferably designed as a plastic window cages bearing cages, while in the arrangement of the two pairs of rows on each parallel Druckwinkelachsen each pair of rows in one common storage cage can be performed, which is also preferably designed as a plastic window cage.

The arrangement of the rolling elements of the two pairs of rows on each diverging to the longitudinal central axis of the angular contact bearing extending pressure angle axes has the advantage that the inclined roller bearing by the large span of the two axially outer rows of rolling elements high tilting stiffness at the same time high Radialtraganteil by the relatively small span of the two receives axially inner rows of rolling elements. In contrast, the arrangement of the rolling elements of the two pairs of rows on each converging to the longitudinal center axis of the angular contact bearing extending pressure angle axes has the advantage that the tilting stiffness of the angular contact bearing thus increases particularly strong can be while the radial load capacity of the angular contact for it slightly lower.

Particularly advantageous, however, the arrangement of the rolling elements of the two pairs of rows has proven parallel to the longitudinal central axis of the angular contact bearing pressure angle axes, as ensured by this arrangement that the individual pairs of ball rollers in both pairs of rows have no speed differences between them and roll synchronously with each other and with each other mutually support adjacent side surfaces. As a result, on the one hand a high packing density or a close arrangement of the ball rollers in the angular roller bearing is possible through which a hochtrag- enabled and extremely low-friction storage, and on the other hand, both pairs of rows can each be performed in a common storage cage, which in addition a gain in volume for defined by the space between the bearing rings fat depot of the angular contact bearing is achieved.

An expedient development of the inventively designed wheel bearing, it is further claim that the outer bearing ring of the angular contact bearing is preferably fully integrated gungsflansches in the hub of the vehicle side mounting flange by the outer raceways of the individual rows of rolling elements directly into the inside of the hub of the vehicle side Mounting flange are incorporated. This training is known per se from conventional wheel bearings of the 2nd and 3rd integration stage and has proved to be the most advantageous from a production point of view and in view of low production costs even with the wheel bearing according to the invention. It is of course also possible, and wheel bearings of the 1st Integration stage, which have a separate, in the hub, a vehicle-side mounting flange arranged outer bearing ring, form in accordance with the invention with ball rollers as rolling elements.

Likewise, it has for the inner raceways of the individual rows of rolling elements having inner bearing ring of the inventively designed oblique roller bearing proved to be advantageous, this, as of conventional Wheel bearings of the 1. and 2nd integration stage known to form in a first embodiment according to claim 7 of two separate solid part rings of a bearing steel. Such formed inner bearing ring is characterized by a high dimensional stability and wear resistance and has proven itself in practice. On the other hand, a particularly cost-effective alternative is the variant of the first embodiment also proposed by claim 8, in which the inner bearing ring is formed from two separate cold-formed partial rings made of a deep-drawable bearing steel. 100Cr6mod or C80M has proven to be the most suitable material, so that even an inner bearing ring produced in this way fulfills the necessary requirements for dimensional stability and wear resistance. Regardless of their production, the partial rings of the inner bearing ring are then fixed in position on the one hand on a shoulder on the hub of the wheel-side mounting flange and on the other hand clamped by a flange on this hub against each other.

As an alternative second embodiment of the inventively designed wheel bearing, it is finally proposed by the claims 9 and 10, to form the inner race of the angular rolling bearing on the one hand by a the inner raceways of a series pair of rolling elements having separate partial ring and the other in the hub of the wheel side To integrate mounting flange by the inner raceways of the other row pair of rolling elements are incorporated directly into the outside of this hub. The separate sub-ring of the inner bearing ring can then also be made optionally of a deep-drawn or roller bearing steel and on the one hand on a side mounted in the hub inner raceways of the other row pair arranged paragraph fixed on the hub of the wheel-side mounting flange and on the other hand by a Bördelbord this hub be tightened against the paragraph. In summary, the wheel bearing according to the invention thus has the advantage over the wheel bearings known from the prior art, that by using ball rollers as rolling elements designed as a multi-row angular contact ball bearing without changes the surrounding construction has a substantial increase in load capacity and rigidity and thus a longer service life.

Brief description of the drawings

The inventively designed wheel bearing will be explained in more detail below with reference to the accompanying drawings in several preferred embodiments. Showing:

Figure 1 shows a cross section through a first embodiment of the inventively designed wheel bearing;

Figure 2 shows a cross section through a variant of the first embodiment of the inventively designed wheel bearing;

Figure 3 shows a cross section through a second embodiment of the inventively designed wheel bearing;

4 shows a cross section through a third embodiment of the inventively designed wheel bearing.

Detailed description of the drawings

From Figures 1 to 4 clearly go out four different embodiments of a wheel bearing for motor vehicles, which consists essentially of a four-row angular contact bearing 1, which is arranged on a hub 2 of a wheel-side mounting flange 3 or at least partially integrated in this inner bearing ring 4, 4a and a coaxial with this integrated into a hub 5 of a vehicle-side mounting flange 6 outer bearing ring 7 and with a plurality in four rows 8, 9, 10, 1 1 side by side between these bearing rings 4, 4a, 5 arranged rolling elements 12 is formed. Likewise, the drawings can be taken that the rolling elements 12 of the angular contact roller bearing 1 on obliquely adjusted pressure angle axes 13, 14, 15, 16 in groove-shaped raceways 17, 18, 19, 20 and 21, 22, 23, 24 in both bearing rings 4, 4a, 5 roll and be held by a plurality of bearing cages 25, 26, 27, 28 in the circumferential direction at regular intervals to each other.

In addition, it is clearly visible in all figures that all rolling elements 12 of the individual rows 8, 9, 10, 1 1 of the angular rolling bearing 1 are designed according to the invention as ball rollers, each having two symmetrically flattened from a spherical base and arranged parallel to each other side surfaces. Between these side surfaces, the ball rollers have a width reduced by 20% to 30% relative to the diameter of their ball base shape, so that the rolling elements 12 used to increase the bearing capacity and rigidity of the angular rolling bearing 1 with considerably larger diameters than conventional bearing balls no additional axial space need.

Furthermore, the four embodiments of the wheel bearing according to the invention shown in the drawings have in common that the identical pitch diameter T _K i of the two axially inner rows 9, 10 smaller than the also identical pitch circle diameter J _{K2 of} the two axially outer rows 8, 1 1 is formed while at the same time the diameter of the ball basic shape of the rolling elements 12 of the two axially outer rows 8, 1 1 relative to the diameter of the ball basic shape of the rolling elements 12 of the two axially inner rows 9, 10 is formed larger. In each case, an axially outer row 8, 1 1 and arranged next to the axially inner row 9, 10 of the rolling elements 12 a first and a second row pair 29, 30, in which the pressure angle axes 13, 14, 15, 16 of the rolling elements 12 either in FIGS. 1 and 2, diverging or, as in FIG. 3, converging or, as in FIG. 4, arranged mutually parallel to the longitudinal central axis 31 and which are each set up axially mirror-inverted or in an O-arrangement against one another. Furthermore, it is shown in FIGS. 1 to 3 that, when the two pairs of rows 29, 30 are arranged on respectively diverging or converging pressure-angle axes 13, 14, 15, 16, each row 8, 9, 10, 11 of the rolling elements 12 is separated into plastic strips. Window cages trained bearing cages 25, 26, 27, 28 out is, while in arrangement of the two pairs of rows 29, 30 on each parallel Druckwinkelachsen 13, 14, 15, 16, as shown in Figure 4, each pair of rows 29, 30 in a common also formed as a plastic window cage bearing cage 25, 26 is performed.

With regard to the formation of the outer bearing ring 7 of the angular contact bearing 1, it is yet another common feature of the wheel bearings according to the invention shown that this is completely integrated into the hub 5 of the vehicle-side mounting flange 6 by the outer raceways 21, 22, 23, 24 of the individual rows 8, 9, 10, 1 1 of the rolling elements 12 are incorporated directly into the inside of the hub 5 of the vehicle-side mounting flange 6. However, as a difference between the individual embodiments of the wheel bearings according to the invention is clearly visible that with the inner raceways 17, 18, 19, 20 of the individual rows 8, 9, 10, 1 1 of the rolling elements 12 formed inner bearing ring 4, 4a of Figure 1 illustrated first embodiment of the angular contact roller bearing 1 consists of two separate solid part rings of a rolling bearing steel, while the inner bearing ring 4, 4a of the variant of the first embodiment shown in Figure 2 formed of two separate cold-formed partial rings of a thermoformable roller bearing steel.

On the other hand, the second embodiment of the angular rolling bearing 1 shown in FIG. 3 differs from the first embodiment in that the inner bearing ring 4, 4a of the angular rolling bearing 1 is separated by a raceway 19, 20 of one row pair 30 of the rolling elements 12 Partial ring 4a is formed and on the other hand is integrated into the hub 2 of the wheel-side mounting flange 3 by the inner raceways 17, 18 of the other row pair 29 of the rolling elements 12 are incorporated directly into the outside of this hub 2. In contrast, in the case of the third embodiment of the angular contact bearing 1 shown in FIG. 4, the design of the inner bearing ring 4, 4a is again essentially the first embodiment, but different from the other embodiments by the arrangement of the two pairs of rows 29, 30 of the rolling elements 12 on each parallel Druckwinkelachsen 13, 14, 15, 16, different.

Finally, as the last common feature of all four embodiments of the wheel bearing according to the invention, it is clear from FIGS. 1 to 4 that the partial rings of the inner bearing ring 4, 4a are firmly seated on the hub 2 of the fastening flange 3 and regardless of the manner of their manufacture an outer side of a partial ring on a shoulder 32 on the hub 2 of the wheel-side mounting flange 3 are fixed in position. On the other side, the hub 2 of the mounting flange 3 then has a radially outwardly formed flange 33, which is pressed against the other outer side of the other part ring of the inner bearing ring 4a and thus clamped both partial rings of the inner bearing ring 4, 4a against each other.

LIST OF REFERENCE NUMBERS

Angular bearings

Hub of 3

Mounting flange inner bearing ring

Partial ring of 4

Hub of 6

Mounting flange outer bearing ring

rolling body row

rolling elements

Contact angle axis

Pressure angle axis Inner raceway Inner raceway Inner raceway Inner raceway Outer raceway Outer raceway Outer raceway Outer raceway

bearing cage

pair of rows

pair of rows 31 longitudinal central axis

32 paragraph

33 flaring board

Tκi pitch circle diameter of 9, 10

T _K2 pitch circle diameter of 8, 1 1

Claims

claims

1. Wheel bearing for motor vehicles, consisting essentially of a multi-row skewed roller bearing (1) arranged on a hub (2) of a wheel-side mounting flange (3) or at least partially integrated in this inner bearing ring (4, 4a) and a coaxial for this in a hub (5) of a vehicle-side mounting flange (6) arranged or at least partially integrated in this outer bearing ring (7) and with a plurality in several rows (8, 9, 10, 1 1) side by side between these bearing rings (4, 4a, 5) arranged rolling elements

(12) is formed on obliquely set defined Druckwinkelachsen (13, 14, 15, 16) in groove-shaped raceways (17, 18, 19, 20 and 21, 22, 23, 24) in both bearing rings (4, 4a, 5 ) are held by a plurality of bearing cages (25, 26, 27, 28) in the circumferential direction at regular intervals to each other, characterized in that all

Rolling elements (12) of the angular rolling bearing (1) are formed as spherical rollers with two symmetrically flattened from a spherical base and arranged parallel to each other side surfaces between which they have a reduced by 20% to 30% compared to the diameter of their ball basic shape.

2. wheel bearing according to claim 1, characterized in that the inclined roller bearing (1) preferably four rows (8, 9, 10, 1 1) formed as ball rolling elements (12), of which preferably identi see pitch circle diameter (T _K i) of the two axially inner rows (9, 10) smaller than the likewise preferably identical pitch circle diameter (Tκ ₂ ) of the two axially outer rows (8, 1 1) is formed.

3. wheel bearing according to claim 2, characterized in that the diameter of the ball basic shape of the rolling elements (12) of the two axially outer rows (8, 1 1) relative to the rolling elements (12) of the two axially inner rows (9, 10) formed larger is and in each case an axially outer He (8, 1 1) and arranged next to the axially inner row (9, 10) of the rolling elements (12) form a first and a second row pair (29, 30).

4. wheel bearing according to claim 3, characterized in that the pressure angle axes (13, 14, 15, 16) of each pair of rows (29, 30) of the rolling elements

(12) to the longitudinal central axis (31) of the angular rolling bearing (1) arranged either diverging or converging or parallel to each other and both pairs of rows (29, 30) of the rolling elements (12) are axially mirror image in O arrangement against each other employed.

5. wheel bearing according to claim 4, characterized in that in the arrangement of the two pairs of rows (29, 30) on each diverging or converging Druckwinkelachsen (13, 14, 15, 16) each row (8, 9, 10, 1 1) of the rolling elements (12) in separate bearing cages (25, 26, 27, 28) is guided, while in arranging the two pairs of rows (29, 30) on each parallel Druckwinkelachsen (13, 14, 15, 16) each pair of rows (29, 30) in a common bearing cage (25, 26) is guided.

6. wheel bearing according to claim 1, characterized in that the outer bearing ring (7) of the angular rolling bearing (1) is preferably completely integrated into the hub (5) of the vehicle-side mounting flange (6) by the outer raceways (21, 22, 23, 24) of the individual rows (8, 9, 10, 1 1) of the rolling elements (12) are incorporated directly into the inside of the hub (5) of the vehicle-side mounting flange (6).

7. Wheel bearing according to claim 6, characterized in that with the inner raceways (17, 18, 19, 20) of the individual rows (8, 9, 10, 1 1) of the rolling elements (12) formed inner bearing ring (4, 4a ) of the oblique roller bearing (1) preferably consists of two separate solid part rings of a Wälzla- gerstahl which on the one hand to a shoulder (32) on the hub (2) of the wheel-side mounting flange (3) fixed in position and on the other hand by a Bördelbord (33) on this hub (2) are braced against each other.

8. Wheel bearing according to claim 6, characterized in that with the inner raceways (17, 18, 19, 20) of the individual rows (8, 9, 10, 1 1) of the rolling elements (12) formed inner bearing ring (4, 4a ) of the angular rolling bearing (1) preferably consists of two separate cold-formed partial rings of one

Deep-drawn steel consists, on the one hand at a shoulder (32) on the hub (2) of the wheel-side mounting flange (3) fixed in position and on the other hand braced by a flange (33) on this hub (2) against each other.

9. Wheel bearing according to claim 3, characterized in that the inner bearing ring (4, 4a) of the angular rolling bearing (1) by a the inner raceways (19, 20) of a row pair (30) of the rolling elements (12) having separate partial ring (4a) is formed and on the other hand in the hub (2) of the wheel-side mounting flange (3) is integrated by the inner raceways (17, 18) of the other row pair (29) of the rolling elements (12) directly into the outside of this hub ( 2) are incorporated.

10. Wheel bearing according to claim 9, characterized in that the separate partial ring (4 a) of the inner bearing ring (4, 4 a) optionally consists of a deep-drawn or roller bearing steel and on the one hand to the in the hub (2) incorporated inner raceways (17, 18) of the other row pair (29) arranged shoulder (32) on the hub (2) of the wheel-side mounting flange (3) fixed in position and on the other hand braced by a flange (33) on this hub (2) against the shoulder (32) is.