DE102020122667A1 - bearing arrangement - Google Patents

Abstract

The invention relates to a bearing arrangement comprising two cylindrical roller bearings (2, 3) which are arranged coaxially, a first shaft (4) being able to be mounted in the first cylindrical roller bearing (2) and a second shaft (5) being able to be mounted in the second cylindrical roller bearing (3), an axial needle bearing (7) for mutual support of the shafts (4,5) being arranged in a region between the end faces of the shafts (4,5) which face one another in the axial direction between the cylindrical roller bearings (2,3), characterized that an end face (2d) of the first cylindrical roller bearing (2) forms a first raceway for the axial needle bearing (7).

Description

The invention relates to a bearing arrangement with two cylindrical roller bearings for supporting two shafts and an axial bearing arranged between them.

the DE 10 2013 210 693 A1 discloses a bearing assembly for two adjacent gears of a dual clutch transmission. An axial roller bearing is arranged between the mutually facing end faces of the gear wheels. The gears are mounted on a shaft in radial roller bearings. A configuration is proposed with which it is possible to omit a ring shoulder on the shaft and still prevent axial displacement of the radial roller bearings with a central stop.

the DE 10 2010 007 706 A1 shows a bearing combination that is very easy to assemble. A radial bearing and an axial bearing are designed in such a way that they support a bearing partner in an axial and radial direction and are captively connected to holding means.

The invention is based on the object of proposing a bearing arrangement made up of two cylindrical roller bearings and one axial bearing, which is particularly advantageous with regard to the installation space required.

This problem is solved by a bearing combination with the features of claim 1. Preferred or advantageous embodiments of the invention result from the dependent claims, the following description and the attached figures.

The invention therefore proposes a bearing arrangement comprising two cylindrical roller bearings which are arranged coaxially, a first shaft being able to be mounted in the first cylindrical roller bearing and a second shaft being able to be mounted in the second cylindrical roller bearing, wherein in an area between the end faces of the shafts, which extends in the axial direction face each other between the cylindrical roller bearings, a thrust needle bearing is arranged for mutual support of the shafts and wherein an end face of the first cylindrical roller bearing forms a first raceway for the thrust needle bearing.

The invention is based on the knowledge that it is possible to arrange an axial needle bearing directly on the end face of a cylindrical roller bearing in such a way that no running surface assigned to the axial needle bearing as an autonomous component is provided. Such an arrangement initially appears to be of little advantage since the axial needle bearing cannot be designed, conceived and assembled as an independent component with regard to its running and wear properties and its ability to be assembled. According to the invention, however, the design and formation of the running surface for the axial needle bearing rolling elements on the end face of a solid cylindrical roller bearing is not only possible, but also leads to a gain in axial space, which can be a decisive advantage depending on the application.

A second raceway for the axial needle bearing is preferably formed on the end face of the second cylindrical roller bearing. This results in a corresponding further space advantage. The respective raceways for the axial needle bearing are preferably formed on the respective inner rings of the cylindrical roller bearings.

Preferably, the needle rollers of the thrust needle bearing are cylindrical and the first and second raceways are contoured in the radial direction with a profile such that the ends of the needle rollers have reduced contact with the raceways in comparison to the centers of the needle rollers. What is achieved in particular with this design is that the acoustic properties of the bearing arrangement are improved. More preferably, the profiling is only designed to be so deep that tilting and the resulting susceptibility to wear remain within an acceptable range over a target service life. In that the profiling thus reduces the contact surface of the rolling elements of the axial needle bearing with their running surfaces, noise generation is reduced. However, the profiling is only carried out to such an extent that the rolling elements are not exposed to excessive wear with regard to the designed service life due to tilting and unstable running. The profiling is preferably produced by machining the cylindrical roller bearing or bearings.

The bearing arrangement is preferably used in an electric drive axle for a motor vehicle. In the case of an electrically driven motor vehicle in particular, the requirements for low noise generation from a bearing arrangement are particularly high.

• 1 eine schematische Schnittansicht einer Lageranordnung für zwei Wellen in zwei Zylinderrollenlagern;
• 2 ein Längsschnitt durch den Innenring eines der Zylinderrollenlager und einem Axialnadellager;
• 3 eine Detailansicht zu 2.

Further features, advantages and effects of the invention result from the following description of a preferred exemplary embodiment of the invention and the attached figures. show:

• 1 a schematic sectional view of a bearing arrangement for two shafts in two cylindrical roller bearings;
• 2 a longitudinal section through the inner ring of one of the cylindrical roller bearings and an axial needle bearing;
• 3 a detailed view 2 .

1 shows a bearing arrangement 1. Two shafts 4.5 are mounted radially in two cylindrical roller bearings 2.3. Two end faces 4a, 5a of the first and second shaft 4.5 face one another. The cylindrical roller bearings 2, 3 are arranged in the area of these end faces 4a, 5a. The cylindrical roller bearings 2.3 each have an inner ring 2a, 3a and an outer ring 2b, 3b. The inner ring 2a is connected to the shaft 2, while the inner ring 3a is connected to the shaft 5. The outer rings 2b, 3b are connected to a housing 6. Cylindrical rolling elements 2c, 3c are provided between the inner rings 2a, 3a and the outer rings 2b, 3b.

An axial needle bearing 7 is now arranged between the shafts 4, 5, more precisely between the inner rings 2a, 3a. This is based on the 2 and 3 described in more detail.

In 2 the inner ring 2a of the cylindrical roller bearing 2 is shown in a longitudinal section. The axial needle bearing 7, which has rolling elements 7a, is arranged on its end face 2d (see Fig. 3 ), which are arranged in an axial needle bearing cage 7b. The axial needle bearing cage 7b surrounds the inner ring 2a in such a way that it is held radially. In 3 is a snippet 2 shown, in which the end face 2d of the inner ring 2a is shown enlarged. A profiling P of this face 2d is recognizable. This profiling causes the end face 2d to recede in the radial direction, namely radially outwards and inwards from a central area. The central area is that area in which the rolling elements 7a of the axial needle bearing 7 contact the end face 2d between the outer end B of the rolling element and the inner end A of the rolling element. The end face 2d is therefore designed as a running surface of the axial needle bearing 7 . The profiling P means that the rolling elements 7a can be made cylindrical and at the same time the contact surface with the inner ring 2a is reduced in such a way that noise is minimized when the rolling elements 7a run off. Here, for the profiling P, it is taken into account that the contacting surface is still large enough to keep tilting and thus instability of the running of the rolling bodies 7a so low that no unacceptable wear occurs over the designed service life.

Reference List

1

bearing arrangement

2

first cylindrical roller bearing

2a

first cylindrical roller bearing inner ring

2 B

first cylindrical roller bearing outer ring

2c

first cylindrical roller bearing rolling elements

2d

Face of first cylindrical roller bearing

3

second cylindrical roller bearing

3a

second cylindrical roller bearing inner ring

3b

second cylindrical roller bearing outer ring

3c

second cylindrical roller bearing rolling elements

3d

Face of second cylindrical roller bearing

4

first wave

4a

Face of first shaft

5

second wave

5a

Face of the second shaft

6

housing

7

axial needle bearing

7a

Thrust needle bearing rolling elements

7b

Thrust needle bearing cage

P

profiling

A

Inner rolling element end

B

Outer end of rolling element

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 102013210693 A1 [0002]
• DE 102010007706 A1 [0003]

Claims (7)

Bearing arrangement, comprising two cylindrical roller bearings (2, 3) which are arranged coaxially, a first shaft (4) being storable in the first cylindrical roller bearing (2) and a second shaft (5) being storable in the second cylindrical roller bearing (3), wherein in one area an axial needle bearing (7) for mutual support of the shafts (4,5) is arranged between the end faces of the shafts (4,5), which face one another in the axial direction between the cylindrical roller bearings (2,3), characterized in that one end face (2d) of the first cylindrical roller bearing (2) forms a first raceway for the axial needle bearing (7). Bearing arrangement (1) according to claim 1 , characterized in that an end face (3d) of the second cylindrical roller bearing (3) forms a second raceway for the axial needle bearing (7). Bearing arrangement (1) according to claim 2 , characterized in that the respective raceways are formed on the respective inner rings (2a, 3a) of the cylindrical roller bearings (2,3). Bearing arrangement (1) according to claim 1 or 2 , in which the needle rollers (7a) of the axial needle bearing (7) are cylindrical and the first and second raceways are contoured in the radial direction with a profiling (P) in such a way that the ends of the needle rollers (7a) have reduced contact with the raceways in the im Have compared to the centers of the needle rollers (7a). Bearing arrangement (1) according to claim 3 , in which the profiling (P) is only so deep that tilting and the resulting susceptibility to wear remain within an acceptable range over a target service life. Bearing arrangement (1) according to claim 3 or 4 , in which the profiling (P) is made by machining the cylindrical roller bearing or bearings (2.3). Electric drive axle for a motor vehicle, with a bearing arrangement (1) according to one of the preceding claims

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