DE102021119494A1 - Double row thrust roller bearing - Google Patents

Abstract

The invention relates to an axial roller bearing with rolling elements (2a, 2b) guided in a bearing cage (1), the bearing cage (1), which consists of a one-piece formed sheet metal material, having an inner cage ring area (3b) and an outer cage ring area (3a ) which is formed on the inner cage ring area (3b) via a center edge section (4) running in the axial direction in such a way that the common center edge section (4) is part of both cage ring areas (3a, 3b), both cage ring areas (3a, 3b) with are each provided with a sigma profile (6a; 6b) for receiving the rolling bodies (2a; 2b), which are designed pointing in opposite axial directions.

Description

The present invention relates to an axial roller bearing with roller bodies guided in a bearing cage.

The field of application of the invention extends primarily to motor vehicle technology. Axial roller bearings of the type of interest here are primarily used for pivoting or rotating bearings of components - for example spindle shafts - which are exposed to a particularly high axial load during operation, which requires an axial bearing with a particularly high load capacity.

State of the art

From the DE 10 2015 201 485 A1 shows a double-row axial roller bearing of the type of interest here, which is designed as an axial needle bearing. The axial needle bearing essentially consists of an angle washer and an outer axial needle ring inserted into this angle washer and an inner axial needle ring arranged coaxially to this and also inserted into the angle washer is formed on the angle disk of rolling bearing needles. Each of the two axial needle cages acting as a bearing cage consists of an annular disk with a W-shaped or H-shaped profile cross-section. Such profile cross sections are referred to as sigma profiles in the context of the present application, since the contour of the profile cross section resembles the Greek letter sigma; With reference to the German alphabet, the profile cross section resembles the letter W when rotated by 90° or - viewed from the opposite direction - the letter M. The transitions of the letter flanks do not have to end in an acute angle, but can also be flattened or rounded.

The prior art cited above shows the flattened variant of a sigma profile. Each rolling element comes to rest with the two opposite end faces on the outer flanks of the sigma profile to form a radial guide while maintaining a clearance fit. In contrast, the raised central area of the sigma profile limits the clearance fit of the rolling elements used between adjacent sigma profiles in the circumferential direction.

In the aforementioned prior art, the outer axial needle cage is positively connected to the inner axial needle cage in that an inner radial outer edge section of the outer axial needle cage engages in an outer outer edge section of the inner axial needle cage. For this purpose, the two corresponding edge sections have an interlocking U-profiling.

This divided construction of the double-row bearing cage results in the need for an assembly step when fitting the same with the rolling elements. In addition, the U-shaped interlocking edge sections are to be manufactured with such precision that neither jamming, which impairs the geometry of the cage guide, nor excessive fitting play occurs in order to achieve an axial bearing with a long service life. In addition, the positive-locking fastening means of the bearing cages connected to one another require a corresponding amount of space, so that an arrangement of two rolling element circuits is only possible at a minimum radial distance that depends on these design features of the bearing cage.

It is therefore the object of the present invention to further improve a double-row axial roller bearing of the generic type in such a way that its easy-to-assemble and material-saving bearing cage makes do with minimal installation space.

Disclosure of Invention

The object is achieved by an axial roller bearing according to claim 1. The following dependent claims reflect advantageous developments of the invention.

The invention includes the technical teaching that an axial roller bearing of the aforementioned type has a bearing cage made in one piece from a formed sheet metal material, which has an inner cage ring area and an outer cage ring area arranged coaxially around it, which is connected to the inner Cage ring area is formed, that the common central edge portion is a stabilizing part of both cage ring areas, the two cage ring areas are designed specifically as sigma profiles, which are designed pointing in mutually opposite axial directions.

In other words, the common middle edge section of both ring cage areas forms the prerequisite for the fact that the radial distance between the two rows of rolling elements can be reduced in a space-saving manner. This does not affect the high load capacity of the axial roller bearing. In addition, for the production of the bearing cage according to the invention compared to dis According to the prior art, less sheet metal material is required, since the material for forming the positively interlocking connecting sections is eliminated. Instead, the common central edge section forms an inner edge section for the outer ring cage area and an outer edge section for the inner ring cage area. Due to the component rigidity resulting from the one-piece nature of the bearing cage according to the invention, the bearing friction is reduced since the shape according to the invention also prevents rolling elements from contacting one another in the radial direction through the common central edge section lying in between. In this way, the rows of rolling elements can be determined with an optimal web width in the root circle of the respective row of rolling elements in order to achieve the desired high load capacity.

According to the invention, the sigma profiles pointing in mutually opposite axial directions are in other words aligned as mirror images of one another, so that the trailing edge of one cage ring area forms the incoming edge of the adjacent cage ring area, both of which are combined to form the common middle edge section. Thus, a further inverted sigma profile directly follows a known sigma profile in the radial direction, with the adjacent edge sections forming the common central edge section.

Cage pockets for accommodating rolling elements in the form of needles or rollers are created by two sigma profiles spaced apart from one another in the circumferential direction and forming bearing webs. The rolling elements inserted here are guided in the circumferential direction by the sigma profile.

The construction according to the invention forms the manufacturing prerequisite for the function-integrated bearing cage to be able to be produced in a follow-on tool, with which the bearing cage for the two cage ring areas can be produced with a single tool stroke by stamping and bending.

Based on the prior art discussed in the introduction to the description, in the context of the present application, a sigma profile is understood to be a contour that, viewed from radially inside to radially outside, begins with a short radial edge section that transitions into a rising flank section that extends essentially in the axial direction. This is followed by a further radially extending crest section which merges into a descending flank section which preferably has the same length as the ascending flank section. This in turn is followed by a short radial section. The short radial sections formed on both sides of the sigma profile merge into associated, essentially axially running edge sections, of which one of the axial edge sections is the central edge section.

The two sigma profiles, which are aligned as mirror images of one another, each engage with the short radial sections facing one another at one end of the essentially axially running common central edge section.

In addition to the common middle edge section, the bearing cage according to a preferred embodiment of the invention has an outer peripheral edge section also running in the axial direction on the outer cage ring area, which is preferably formed onto the outer radial edge sections of the sigma profiles. Analogous to this, according to the preferred embodiment, the inner cage ring area also has an inner peripheral inner edge section running in the axial direction, which is preferably formed onto the inner radial edge sections of the sigma profiles. The three edge sections, each aligned in the axial direction, namely the inner edge section, the central edge section and the outer edge section, contribute to the high rigidity of the bearing cage and have approximately the same profile height, from which the rolling elements naturally protrude at least slightly in order to implement the roller bearing.

The bearing cage designed according to the invention can be provided with further attachment options in order to replace previously known bearing cages of the same type with a wide variety of shapes. For example, the inner and/or outer edge section on the bearing side can be provided with a disk extension section molded onto it for diameter adjustment. Such a pane extension section can be formed flat or, preferably, angled at the edge.

The bearing cage that is the subject of the invention is preferably used in the context of an axial roller bearing, the rolling bodies of which are designed in the form of rollers or needles, so that a double-row axial needle bearing can very preferably be realized herewith.

The raceways for the rolling elements can be placed in separate axial bearing halves, for example hardened axial bearing washers; however, it is also conceivable for the raceways to be formed as an integral part of the component ends to be axially supported, for example as an end face of a shaft to be supported axially in connection with a bottom surface of a housing recess corresponding thereto. Mixed forms are also conceivable.

character list

• 1 eine komplette perspektivische Ansicht eines Axialwälzlagers ohne separate Axiallagerscheiben,
• 2 einen perspektivischen Längsschnitt durch das Axialwälzlager nach 1,
• 3 einen perspektivischen Längsschnitt durch den Lagerkäfig des Axialwälzlagers nach 1, und
• 4 eine komplette perspektivische Ansicht des Lagerkäfigs nach 3.

Further measures improving the invention are presented in more detail below together with the description of a preferred exemplary embodiment of the invention with reference to the figures. It shows:

• 1 a complete perspective view of a thrust roller bearing without separate thrust bearing washers,
• 2 a perspective longitudinal section through the axial roller bearing 1 ,
• 3 a perspective longitudinal section through the bearing cage of the axial roller bearing 1 , and
• 4 a complete perspective view of the bearing cage 3 .

According to 1 an axial roller bearing with two adjacent rolling element rings essentially consists of rolling elements 2a, 2b (example) guided by means of bearing cage 1, with bearing cage 1 accommodating and guiding a first, outer row of rolling elements 2a and a second, inner row of rolling elements 2b enclosed by it. In this exemplary embodiment, the rolling bodies 2a and 2b are designed as needles, so that this axial roller bearing represents an axial needle bearing.

After 2 the integrated bearing cage 1 combines an outer cage ring area 3a and an inner cage ring area 3b surrounding it coaxially. A middle edge section 4 running in the axial direction forms the transition area between the outer cage ring area 3a and the inner cage ring area 3b. The axially directed central edge section 4, which is common to this extent, is therefore a component of both cage ring regions 3a and 3b.

As a further add-on feature, a disc extension section 5 molded directly onto the inner cage ring area 3b is provided for the purpose of adjusting the axial roller bearing on the inside diameter side.

According to 3 the two cage ring areas 3a and 3b are each provided with a sigma profile 6a and 6b, respectively, which are designed to point in opposite axial directions, to accommodate the rolling elements (not shown here). In addition to the central edge section 4 running in the axial direction, the bearing cage 1 also has an outer circumferential outer edge section 7 also running in the axial direction on the outer cage ring area 3a and an inner circumferential inner edge section 8 running in the axial direction on the inner cage ring area 3b.

The web-forming sigma profiles 6a of the outer cage ring area 3a are offset relative to the web-forming sigma profiles 6b of the inner cage ring area 3b, viewed in the circumferential direction.

After 4 the contour course of an exemplary sigma profile, seen from radially inside to radially outside, begins with a short radial edge section 9, which transitions into a rising flank section 10 extending essentially in the axial direction. This is followed by a further radially running peak section 11, which merges into a descending flank section 12, which has the same length as the ascending flank section 10 in this exemplary embodiment. This in turn is followed by a short radial section 13 . The short radial sections 9 and 13 formed on both sides of each sigma profile merge into associated, essentially axially running edge sections, namely the outer edge section 7, the inner edge section 8 and the middle edge section 4.

The invention is not limited to the preferred embodiment described above. Rather, modifications of this are also conceivable, which are included in the scope of protection of the following claims. For example, it is also possible to use a different rolling body shape. It should also be pointed out that the axial roller bearing according to the invention can be used with separate axial bearing disks as axial bearing halves, but can also be used without them.

Reference List

1

bearing cage

2

rolling elements

3

cage ring area

4

center edge section

5

disc extension section

6

sigma profile

7

outer edge section

8th

inner edge section

9

radial edge section

10

flank section

11

summit section

12

flank section

13

radial edge section

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was 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.

Patent Literature Cited

• DE 102015201485 A1 [0003]

Claims (9)

Axial rolling bearing with rolling elements (2a, 2b) guided in a bearing cage (1), wherein the bearing cage (1), which consists of a formed sheet metal material in one piece, has an inner cage ring area (3b) and an outer cage ring area (3a) arranged coaxially therearound for axial bearing is formed on the inner cage ring area (3b) via a center edge section (4) running in the axial direction in such a way that the common center edge section (4) is part of both cage ring areas (3a, 3b), both cage ring areas (3a, 3b) each having a sigma profile ( 6a; 6b) for receiving the rolling bodies (2a; 2b), which are designed pointing in opposite axial directions. axial roller bearing claim 1 , characterized in that the outer cage ring region (3a) has an outer peripheral axially extending outer edge portion (7). axial roller bearing claim 1 , characterized in that the inner cage ring portion (3b) has an inner peripheral axially extending inner edge portion (8). Axial roller bearing according to one of the preceding claims, characterized in that the inner and/or outer edge section (7; 8) on the bearing side is provided with a disc extension section (5) formed thereon for diameter adjustment. Axial rolling bearing according to one of the preceding claims, characterized in that the rolling bodies (2a, 2b) are designed in the form of rollers or needles. Axial rolling bearing according to one of the preceding claims, characterized in that raceways for the rolling bodies (2a, 2b) are formed on a separate axial bearing disc and/or are an integral part of a component to be axially supported. Axial roller bearing according to one of the preceding claims, characterized in that the web-forming sigma profiles (6a) of the outer cage ring area (3a) are offset relative to the web-forming sigma profiles (6b) of the inner cage ring area (3b) in the circumferential direction. Axial roller bearing according to one of the preceding claims, characterized in that the contour of the sigma profile, viewed from radially inside to radially outside, initially has a short radial edge section (9), which merges into a rising flank section (10) extending essentially in the axial direction, to which another radially extending Summit section (11) follows, which merges into a descending flank section (12), which in turn is followed by a short radial section (13). Axial roller bearing according to one of the preceding claims, characterized in that the short radial sections (9; 13) formed on both sides of each sigma profile merge into associated essentially axially running edge sections (4; 7; 8).

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