DE102008053248A1 - Rolling bearing cage - Google Patents

Abstract

The invention relates to a roller bearing cage with two circumferentially extending (U) circumferential webs (2, 3), each having a rolling elements (4) facing the inside (5, 6), and with connecting webs (11, 12), between the peripheral webs (2,3) extend and with these pockets (21) for receiving the rolling elements (4) form, wherein the roller bearing cage by frontal contact of the rolling elements (4) on the inside (5, 6) of at least one peripheral ridge (2, 3) axially to be led. To provide a roller bearing cage, which ensures a reliable undisturbed lubricant supply in the critical areas of the rolling bearing end faces, it is provided that the inside (5, 6) in each case to the connecting webs (11, 12) towards a return (40, 41, 42, 43) having.

Description

Field of the invention

The The invention relates to a roller bearing cage with two circumferentially extending peripheral webs, each one have the rolling bodies facing inside, and with connecting webs extending between the peripheral webs and with these pockets for receiving the rolling elements form, wherein the rolling bearing cage by frontal Arrangement of the rolling elements on the inside at least a peripheral ridge is guided axially.

cages for rolling bearings are known in multiple design and have to guide the rolling elements Proven in the pockets provided by them. Especially for large rolling bearings (with a pitch circle diameter more than 500 mm) are increasingly composed of individual cage segments Cages used for weight saving reasons preferably made of plastics such. B. PEEK (polyether ether ketone) are made.

The However, the present invention is generally for rolling bearing cages suitable, without about composed of cage segments Rolling cages to be limited. Even though the invention particularly advantageous in cages for Large rolling bearing with several rows of rolling elements - such as For example, double-row tapered roller bearings - used is, it is also not limited in this respect but basically suitable for all bearing types.

A rolling bearing cage of the type mentioned is from the German patent application DE 10 2006 022 951 A1 known, which describes a cage segment for a cage of a rolling bearing with at least two circumferentially extending peripheral webs - also referred to as longitudinal webs - and at least two connecting webs (transverse webs). The connecting webs form, with the respective section of the circumferential webs extending between them, at least one pocket for receiving a rolling element, in each of which a rolling element is guided axially by abutment of its end faces against the inner sides of the circumferential webs.

The DE 10 2006 022 951 A1 is directed to the provision of a reliable, low-cost rolling bearing cage, with the one hand, mechanical stresses of the cage and on the other hand increased wear due to constraining forces can be avoided. On the problem of the supply of lubricant to the rolling elements in general and the tribological conditions when sliding the Wälzkörperstirnflächen on the axial displacement of the rolling elements limiting so-called Borden the bearing inner ring or the bearing outer ring is the DE 10 2006 022 951 A1 not a.

at the known rolling bearing cage are the insides the peripheral webs essentially flat and possibly - due the sizing just for slewing bearings - with provided a minimum curvature in the circumferential direction. usual Rolling elements, in particular tapered rollers, have the addressed sizing a nearly plane, if necessary very slight spherical crowned rolling element end face on. Since the cage segments usually relative tight over the rolling element lengths are guided, of the peripheral webs are especially the end face areas the rolling element touches the same time also as the mentioned sliding and support surfaces to the ribs on the inner and outer rolling bearing rings serve. At these it can lead to a stripping of the lubricant or lubricant just in these for the friction conditions and the material load particularly critical cooperating surfaces - namely the Wälzkörperstirnflachen on the one hand and the these facing inner surfaces of the rims of the bearing rings on the other hand - come. This can be unfavorable Operating situations a lack of lubricant in the area of this cooperating Sliding surfaces occur. Worst case can this to metallic contact between the rolling elements and lead the rims of the bearing rings, which in turn one increased friction and thus increased wear on Episode has. Medium- and long-term consequence are thereby increased Bearing friction torque and associated increased bearing temperatures, which in turn worsen the lubrication conditions. This self-reinforcing effect can eventually to a significant wear on the cooperating Sliding surfaces (functional surfaces) between rolling elements and the said on-board surfaces as well as disturbances the kinematic conditions in the camp, to compulsive forces and ultimately lead to premature bearing failure.

In front In this background, the object of the invention is the provision a rolling bearing cage, the aforementioned problems eliminated and in particular a reliable undisturbed Lubricant supply in the critical areas of the rolling bearing end faces guaranteed.

These The object is achieved by a rolling bearing cage with the features of the claim 1. Accordingly, a generic rolling bearing cage characterized in that the inner side respectively to the connecting webs has a return.

Advantageous embodiments of the invention are set forth in the following description and the subclaims, the features of which are individually and can be used in any combination.

According to the invention The inside - that of the Wälzkörperstirnfläche facing side of the perimeter ridge - in their respective too the connecting webs leading area a return on. In other words, to the transverse webs is the inside at least one of the circumferential webs within the respective rolling body receiving Pocket opposite the central area of the between the connecting webs located portion of the circumferential ridge radially outward, d. H. from the rolling element end faces away, so it jumps over the middle area the circumferential ridge inside back. This is achieved that the leadership of the cage segments over this middle area - d. H. So about the central section of the perimeter ridge between two connecting bridges - and the central area of the rolling element end faces, z. B. a circular area, takes place. Through this constructive Design by which the inner side surfaces of the peripheral webs withdrawn in the border area to the connecting webs out can, the edge region of the Wälzkörperstirnflächen not touched by the peripheral webs and thus not the lubricant to be influenced. This eliminates the risk of having lubricants is undesirably stripped on the peripheral webs and therefore for sliding lubrication between the rolling element end faces and the insides of the storage shelves (in-board surfaces) not more is available. The lubrication conditions between Wälzkörperstirnflächen and the in-board surfaces stay so completely unaffected by the camp cage.

For the realization of the returns are different advantageous developments of the invention conceivable and appropriate. Particularly preferred may be the recesses by inside material reductions of the peripheral ridge or through material recesses on the circumferential ridge in each case to the outgoing Connecting webs are formed out.

A alternative preferred embodiment of the invention provides that the recesses by an internal material thickening in the central region of the Wälzkörperstirnseite facing portion of the circumferential ridge are formed.

in the Regarding the mechanical loads and in the bearing cage induced mechanical stresses is a development of the invention advantageous according to which the transitions rounded to the recesses are. With that avoiding stress-increasing peaks.

A in this regard, particularly preferred measure for Reduction of these mechanical voltage peaks according to the invention is that in the connection area between the circumference bar and the outgoing one Connecting web at least one undercut is provided.

The The invention further relates to a rolling bearing comprising a Rolling bearing cage according to the invention.

Further Advantages and aspects also arise from the drawing and the now the following description of the embodiments illustrated therein.

there demonstrate:

1 a section (segment) of a rolling bearing cage according to the invention,

2 schematically the leadership situation of a rolling element and

3 a section of a rolling bearing cage with a rolling element.

This in 1 shown segment 1 a rolling bearing cage is in a conventional manner part of a roller bearing with a pitch circle diameter of more than 500 mm, which is suitable for particularly demanding conditions and operating temperatures up to 150 ° C and which may have one or more rows of rolling elements. Such bearings can be particularly preferably used as a rotor main bearing in a wind turbine. Although the description of the figures is given on the basis of such a slewing bearing, the invention is by no means limited thereto or even to rolling bearing cages which are composed of several segments.

As seen in the circumferential direction U, the segment shown comprises 1 of the rolling bearing cage according to the invention two circumferential circumferential webs 2 . 3 , which are sometimes referred to as longitudinal bars. Looking at the respective radius becomes the peripheral ridge 2 also as outer peripheral ridge and the peripheral ridge 3 referred to as inner peripheral ridge. Each girth has a (in 1 not explicitly shown, but only by way of example dashed lines indicated) rolling elements 4 facing inside 5 . 6 on. The peripheral webs are by transverse connecting webs 10 to 14 interconnected and thereby at the same time in several circumferentially adjoining web sections -. B. 16 . 17 . 18 . 19 - divided. The peripheral webs 2 . 3 form with their respective sections (eg 16 . 18 ) and connecting these connecting webs 10 . 11 Bags 20 . 21 . 22 . 23 for the respective recording of a rolling element. The rolling elements are by conditioning their respective radially outwardly or inwardly oriented end face 25 . 26 guided.

The insides 5 . 6 in each case in the connecting or transition areas to the connecting webs 10 . 11 ; 12 . 13 . 14 recesses 30 . 31 . 32 . 33 on. The meaning and function of the recesses, which are preferably formed symmetrically and equally in each pocket, are exemplified below using the bag 21 and by their interaction with the rolling element 4 explained. The recesses 30 . 31 . 32 . 33 are in the embodiment by inside material reductions 35 . 36 . 37 . 38 realized. Thereby are opposite the remaining inside 5 . 6 recesses 40 . 41 . 42 . 43 educated. Between these are inside areas 45 . 46 the peripheral webs 2 . 3 provided, which have a smaller spacing from each other. In other words: Between the respective recesses is a survey, which may be formed in the embodiment by appropriate material reductions, material removal or Materialausnehmungen. Likewise, the returns can 40 . 41 . 42 . 43 but also by inside material thickening in each of the central area 50 . 51 the Wälzkörperstirnseite facing area 45 . 46 of the perimeter ridge 2 respectively. 3 be formed.

As 1 further shows, are the transitions to the recesses 40 to 43 by comparatively large radii, z. B. 56 . 57 formed, so that there is a very gentle and thus mechanical tips degrading transition geometry. Further preferred is in the respective connection region between the respective peripheral ridge 2 . 3 and the respective outgoing connecting bridge 11 . 12 one backstitch z. B. 65 . 66 intended.

2 illustrates the effect of this geometric design, already in 1 by the thus realized, considerably extended distances between the facing surfaces - namely the respective end faces 25 . 26 the rolling elements 4 on the one hand and the facing inner surfaces 5 . 6 the peripheral webs 2 . 3 on the other hand - causes.

As 2 schematically shows in addition, is in the (very schematically illustrated) bag 21 the rolling elements 4 arranged in the form of a tapered roller, wherein the peripheral regions, ie, the outer edge regions of the Wälzkörperstirnflächen not with the material of the cage - ie with the peripheral webs 2 . 3 - come into contact. Rather, mechanical contact is only between the central areas 50 . 51 of the rolling element 4 and the central areas 45 . 46 the bridge sections 17 . 19 intended. This leaves the peripheral areas 70 . 71 the Wälzkörperstirnseiten sufficient lubricant 76 . 77 . 78 . 79 as indicated schematically in the contact area 80 . 81 with the inside 86 . 87 the respectively facing outer Lagerbords 90 or inner storage boards 91 acts.

In order to is ensured by simple means that the inner side surfaces the peripheral webs in the area taken back to the connecting webs out and that thereby the leadership of the cage segments only over the middle area of the circumferential webs between the connecting webs and to the central region of the Wälzkörperstirnflächen out he follows. The inner surfaces on the respective peripheral webs in the middle area of each bag are so elevated and the areas to the larger diameters of End surfaces of the rolling elements withdrawn out. As a result, the edge regions of the Wälzkörperstirnflächen not touched by the cage material and thereby Also, the necessary lubricant can not be undesirable there be stripped off. This is the lubrication behavior between the Rolling elements and the facing Lagerbordinnenseiten optimized and unaffected by the rolling bearing cage.

3 schematically shows a section of a plan view of a cage according to the invention and one in a bag 20 located rolling elements 4 , It can be seen that the rolling element 4 , which is used with the cage according to the invention, a central recess 100 has, which at both end sides of the rolling body 4 is trained. This depression 100 serves the centering of the rolling element during the processing of its lateral surface, ie z. B. when grinding. To the depression 100 closes radially outside a flat surface 101 on the front. This plane surface 101 forms an annular surface and serves as a contact surface with the inner sides, seen here inside 5 , the cage. To the plane surface 101 closes radially outside a curved surface 102 of the rolling element 4 at.

The depression 100 is particularly useful for large rolling elements for easier machining. Of course, the rolling elements without corresponding wells 100 be formed on its end faces. In this case, a circular, planar surface is formed on each end face as a contact surface to the inside of the cage instead of the circular, planar surface 101 out.

1

segment

2, 3

peripheral land

4

rolling elements

5, 6

inside

10 11, 12, 13, 14

connecting webs

16 17, 18, 19

web sections

20 21, 22, 23

Bags

25 26

front sides

30 31, 32, 33

recesses

35, 36, 37, 38

material reductions

40 41, 42, 43

recesses

45, 46

areas

50, 51

centrally Area

56 57

radius

65, 66

undercut

70 71

peripheral Area

76 77, 78 79

lubricant

80 81

contact area

90

outer bearing board

91

internal bearing board

100

deepening

101

plans area

102

curved area

U

circumferentially

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 102006022951 A1 [0004, 0005, 0005]

Claims (6)

Rolling bearing cage - with two circumferentially extending (U) circumferential webs ( 2 . 3 ), each one the rolling elements ( 4 ) facing inside ( 5 . 6 ), and - with connecting webs ( 11 . 12 ) between the peripheral webs ( 2 . 3 ) and with these pockets ( 21 ) for receiving the rolling elements ( 4 ), - wherein the rolling bearing cage by frontal contact of the rolling elements ( 4 ) on the inside ( 5 . 6 ) at least one peripheral ridge ( 2 . 3 ) is axially guided, characterized in that - the inside ( 5 . 6 ) each to the connecting webs ( 11 . 12 ) a return ( 40 . 41 . 42 . 43 ) having. Rolling bearing cage according to claim 1, characterized in that the recesses ( 40 . 41 . 42 . 43 ) by inside material reductions ( 35 . 36 . 37 . 38 ) of the peripheral ridge ( 2 . 3 ) to the connecting webs ( 11 . 12 ) are formed. Rolling bearing cage according to claim 1, characterized in that the recesses ( 40 . 41 . 42 . 43 ) by an internal material thickening in the central area ( 50 . 51 ) of the rolling element end face ( 25 . 26 ) facing section ( 45 . 46 ) of the peripheral ridge ( 2 . 3 ) are formed. Rolling bearing cage according to at least one of claims 1, 2 or 3, characterized in that the transitions to the recesses ( 40 . 41 . 42 . 43 ) are rounded. Rolling bearing cage according to at least one of the preceding claims, characterized in that in the connection area between the peripheral web ( 2 . 3 ) and the respective outgoing connecting bridge ( 11 . 12 ) an undercut ( 65 . 66 ) is provided. Rolling bearing, comprising a rolling bearing cage according to at least one of the preceding claims.