DE102014216522A1 - ball-bearing - Google Patents

Abstract

The invention relates to a ball bearing (2) with a radially outer bearing ring (4) and a radially inner bearing ring (6), wherein the radially inner raceway formed on the radially outer bearing ring (4) and the radially inner bearing ring (6) formed radially outer Track in the cross-sectional profile is formed in each case of at least two merging circular arcs with respect to the radius of the associated bearing balls (8) larger circle radius. In order to adequately support the bearing balls (8) against the action of large axial bearing forces and to minimize the load-induced migration of the contact points between bearing balls and bearing rings, the cross-sectional profile of the raceway of the radially outer bearing ring (4) and / or of the radially inner bearing ring (6) is formed in each case of more than two merging arcs, so that there are more than four contact points.

Description

Field of the invention

The invention relates to a ball bearing with a radially outer bearing ring and a radially inner bearing ring, wherein the formed on the radially outer bearing ring radially inner raceway and formed on the radially inner bearing ring radially outer race in the cross-sectional profile each of at least two merging circular arcs with respect to the radius the associated bearing balls larger circle radius is formed.

Background of the invention

The term bearing ring is here quite generally for that design in which the leaf floats are formed directly on a component to be supported or on a non-rotatable, a component to be stored receiving component, as is well known.

Ball bearings of the type mentioned are generally formed as so-called four-point bearing in which the cross-sectional profile of the radially inner raceway and the radially outer raceway each consists of two merging circular arcs, so that each of the bearing balls via two points of contact on the radially inner raceway and two contact points on the radially outer raceway, so a total of four points of contact is supported. An embodiment of such a four-point camp is on the website http: //www.bs.-wiki- en / mediawiki / images / VierpunktlagerSchnitt , JPG shown.

The DE 10 2011 076 872 A1 shows an example of installation for a slewing bearing, in which two four-point bearing of the above type axially arranged one behind the other, so are combined.

As already mentioned, the radius of the arcs is slightly larger than the radius of the associated bearing balls to ensure a pure point contact. These contact points do not remain constant at the same point in the operation of the bearing relative to the cross-sectional profile, but they change their location in dependence on the thrust bearing on the ball bearing. The greater the axial force acting on the ball bearing, the more the contact points along the circular arcs move outwards, which leads to changes in the contact angle and can considerably affect the bearing parameters. A change in the contact points also results from the fact that under axial load, the bearing balls and the raceway surfaces undergo elastic deformation and form oval contact surfaces. One consequence of this is slippage, friction and wear on the contact surfaces. The above-described effect may be aggravated by errors in the shape of the circular arcs or the raceways caused by machining inaccuracies.

Object of the invention

Against this background, the present invention seeks to provide a ball bearing of the type mentioned, in which a migration of the contact points due to high axial loads and as a result thereof occurring change in the bearing parameters and increased wear largely avoided or at least reduced.

Description of the invention

The solution of this problem arises from the characterizing features of the main claim, while advantageous embodiments and modifications of the invention are the dependent claims.

The invention is based on the finding that with an increase in the number of contact points between the bearing balls and the raceways on the one hand, the burden is better distributed and thus reduced, and on the other hand, the balls are better supported and thus migration of the contact points largely avoided or reduced ,

Accordingly, the invention is based on a ball bearing with a radially outer bearing ring or the like and a radially inner bearing ring or the like, wherein formed on the radially outer bearing ring radially inner raceway and formed on the radially inner bearing ring radially outer race in the cross-sectional profile of at least two in one another merging circular arcs is formed with a relation to the radius of the associated bearing balls larger circle radius.

To achieve the object, it is provided that the cross-sectional profile of the raceway of the radially outer bearing ring and / or the radially inner bearing ring is formed in each case from at least three merging circular arcs, whereby an increase in the number of contact points is reached.

In this case, the cross-sectional profiles of the raceway of the radially outer bearing ring and the raceway of the radially inner bearing ring are preferably formed symmetrically to a central bearing plane perpendicular to the bearing axis, that is, that the ball bearing is equally resilient in both axial directions.

The number of circular arcs of the cross-sectional profile of the raceway of the radially outer bearing ring on the one hand and the raceway of the radially inner bearing ring on the other hand may be different, as will be explained with reference to an embodiment.

According to a preferred embodiment of the invention, the cross-sectional profile of the raceway of the radially outer bearing ring of three circular arcs and the cross-sectional profile of the raceway of the radially inner bearing ring is formed from two circular arcs. Such a configuration is particularly advantageous if, for example, the radially inner bearing ring is divided and thus has a joint in the aforementioned central bearing plane, so that no contact point is provided in this area.

Brief description of the drawings

A preferred embodiment of the invention embodied ball bearing is explained in more detail with reference to the accompanying drawings. Showing:

1 in a partial cross-section of a five-point ball bearing with three contact points on the radially outer bearing ring and two contact points on the radially inner bearing ring, and

2 a representation similar in the 1 , wherein additionally the different contact angles are shown.

Detailed description of the drawings

That in the 1 illustrated five-point ball bearings 2 includes a radially outer bearing ring 4 , a radially inner bearing ring 6 and a number of bearing balls distributed over the bearing circumference 8th from a Ka 10 held and managed. The five-point ball bearing 2 is to one perpendicular to the bearing axis 34 standing middle bearing center plane 11 symmetrically formed, so therefore equally strong loadable in both axial directions.

The cross-sectional profile of the raceway of the radially outer bearing ring 4 is made of three merging circular arcs 12 . 14 . 16 formed on which the bearing balls 8th the three contact points 18 . 20 . 22 form.

The cross-sectional profile of the raceway of the radially inner bearing ring 6 is made of two merging circular arcs 24 . 26 formed, with which the bearing balls 8th two contact points 28 . 30 form. The radius of the circular arcs 12 . 14 . 16 ; 24 . 26 at the two bearing rings 4 . 6 is slightly larger than the sphere radius, so that between the bearing balls 8th and the raceways of both bearing rings 4 . 6 gives a clear point contact. In this way, the bearing balls 8th supported over a total of five contact points. The bearing balls 8th On the one hand, in bearing operation they turn around their own ball axis 32 as well as around the central bearing axis 34 ,

2 shows a simplified representation of the ball bearing 2 according to the 1 with the radially outer bearing ring 4 , the radially inner bearing ring 6 and the bearing balls 8th , The two contact points 18 and 22 the bearing balls 8th with the radially outer bearing ring 4 form with the bearing center plane 11 each a contact angle α, while the intermediate contact point 20 in the bearing center line 11 itself lies. The two contact points 28 and 30 the bearing balls 8th with the radially inner bearing ring 6 each define a contact angle β.

As already mentioned above, the arrangement shown is particularly suitable for a five-point ball bearing, in which the radially inner bearing ring is divided in the axial center and forms a joint, not shown, in which no contact point can be provided. But it is also possible, six or more contact points for each rolling element 8th provided by a corresponding number of circular arcs on the raceways of the two bearing rings.

LIST OF REFERENCE NUMBERS

2

 Five-point ball bearing

4

 Radial outer bearing ring

6

 Radially inner bearing ring

8th

 bearing ball

10

 Cage

11

 Bearing center plane

12

 First circular arc on the outer bearing ring

14

 Second arc at the outer bearing ring

16

 Third arc at the outer bearing ring

18

 First contact point on the outer bearing ring

20

 Second contact point on the outer bearing ring

22

 Third contact point on the outer bearing

24

 First circular arc at the inner bearing ring

26

 Second arc at the inner bearing ring

28

 First contact point on the inner bearing

30

 Second contact point on the inner bearing ring

32

 ball axis

34

 bearing axle

α

 Contact angle at the outer bearing ring

β

Contact angle at the inner bearing ring

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102011076872 A1 [0004]

Cited non-patent literature

• http: //www.bs.-wiki- en / mediawiki / images / Four-Point StorageSection [0003]

Claims (4)

Ball-bearing ( 2 ) with a radially outer bearing ring ( 4 ) and a radially inner bearing ring ( 6 ), wherein the at the radially outer bearing ring ( 4 ) formed radially inner raceway and on the radially inner bearing ring ( 6 ) formed radially outer raceway in the cross-sectional profile in each case of at least two merging circular arcs with respect to the radius of the associated bearing balls ( 8th ) larger circle radius is formed, characterized in that the cross-sectional profile of the raceway of the radially outer bearing ring ( 4 ) and / or the radially inner bearing ring ( 6 ) is formed in each case from at least three merging circular arcs. Ball bearing according to claim 1, characterized in that the cross-sectional profile of the raceway of the radially outer bearing ring ( 4 ) and the cross-sectional profile of the raceway of the radially inner bearing ring ( 6 ) to one on the bearing axis ( 34 ) vertical bearing center plane ( 11 ) are formed symmetrically. Ball bearing according to claim 1 or 2, characterized in that the number of circular arcs ( 12 . 14 . 16 ) of the raceway of the radially outer bearing ring ( 4 ) on the one hand and the number of circular arcs ( 24 . 26 ) of the raceway of the radially inner bearing ring ( 6 ) is different. Ball bearing according to one of claims 1 to 3, characterized in that the cross-sectional profile of the raceway of the radially outer bearing ring ( 4 ) from three circular arcs ( 12 . 14 . 16 ) and the cross-sectional profile of the raceway of the radially inner bearing ring ( 6 ) from two circular arcs ( 24 . 26 ) is formed.

Images