DE102006014108B4 - roller bearing - Google Patents

Abstract

Rolling bearing (1), with an outer ring (2), an inner ring (3) and between them arranged rolling elements (4), wherein the rolling elements (4) by a cage (5) are kept at a distance, wherein the cage (5) at least a radially inner surface or radially outer surface (6, 7) whose radius (r) increases as it progresses in the axial direction (A) to the rolling elements (4) at least in sections,
characterized in that
the cage (5) with its radially inner (6) surface is designed and arranged such that it forms a gap (8) decreasing as it progresses in the axial direction (A) onto the rolling bodies (4) together with the inner ring (3) , wherein the distance (a) at the narrowest point (9) between the cage (5) and inner ring (3) is between 0 mm and 2 mm, wherein the gap (10) between the surface (6, 7) and the inner ring (3) behind the narrowest point (9) as it progresses in the axial direction (A) towards the ...

Description

The Invention relates to a rolling bearing, with an outer ring, an inner ring and between them arranged rolling elements, wherein the rolling elements of a cage be kept at a distance, wherein the cage at least one radial inside or radially outside area whose radius is in the axial direction on the Rolling elements too at least partially enlarged.

A rolling bearing of this kind is from the JP 2001 099 161 A known. There, the problem is recognized that a special structural design of the bearing is necessary to make it suitable in particular for use at high and high speeds. In the cited document, therefore, a cage is provided, the radially inner surface is conical, wherein the radial distance of the inner radial surface to the bearing center increases. In this way, the supply of lubricant can be improved in the area between the rolling elements and raceways, so that the bearing is also suitable for use at high speeds.

A similar embodiment also shows the RU 706 595 , Again, the cage is conically formed on its radially inner side, so that said improved conveying effect for the lubricant can be achieved.

Other similar embodiments of rolling bearing assemblies are known from the DE 101 52 847 A1 , from the DE 23 29 911 A1 , from the US 2 316 449 and from the US 3,096,129 known.

It It has been found that the usable life with these solutions of the camp when using the highest Speeds still insufficient. This is especially true at Application in spindles, some with very high speed have to rotate and are also biased. As a characteristic variable for the speed is For bearings usually the product of speed and average bearing diameter (n × dm) used. At speeds greater than 1.5 million n × dm form the rolling elements quasi a wall for the lubricant is difficult to penetrate. This is true even then if - how at high speeds usually common - oil mist for Lubrication is used.

Of the The invention is therefore based on the object, a rolling bearing of the type mentioned at the beginning so that it is even better for the Use at high speeds is suitable. The camp should in particular be suitable for the bearings of spindles, the high speed rotate, but still need to be stored exactly.

The solution this object by the invention is characterized in that the cage formed and arranged with its radially inner surface is that he along with the inner ring one in progress in the axial direction to the rolling elements forming a shrinking gap, with the distance at the narrowest Place between cage and inner ring between 0 mm and 2 mm, with the gap between the area and the inner ring behind the narrowest point as you progress in Axial direction to the rolling elements too enlarged again and wherein the inner ring at least in a side region in the radial section an S-shaped one Course in the radially outer Has area. Preferred is the distance at the narrowest point between the cage and inner ring or outer ring between 0 mm and 0.8 mm.

hereby In a particularly preferred manner, a nozzle-gap-like structure is produced, the the promotion from lubricant into the bearing favors.

The radially inner surface or radially outer surface preferably formed conical at least in sections. The cone angle the radially inner surface is usually between 10 ° and 20 °, where particularly preferably a value range between 7 ° and 13 ° is provided.

A particular embodiment of the invention provides that the cage with respect to a Center plane of the rolling bearing is formed asymmetrically. As you can see, you can This is a particularly easy way to assemble the Bear camp. The cage can be on one of the two sides of the center plane one in the axial direction extending radially inner surface having a in Axial direction extending portion of the inner ring at a distance opposite. This distance is preferably between 0 mm and 2 mm, especially preferably between 0 and 0.8 mm.

A Development of the invention provides that the axial extent of the cage is larger as the axial extent of the outer ring and / or inner ring. This also causes the effect of lubricant delivery improved in the warehouse. The axial projection of the cage over the Outer ring and / or Inner ring is preferably between 3% and 25% of the axial Width of the rolling elements.

The Invention is particularly preferred for cylindrical roller bearings Use, although it is also quite suitable for other types of storage.

The cage can be mounted on the outer ring, on the inner ring, or be guided on the rolling elements.

Prefers is the cage made of plastic.

In the drawing are embodiments of Invention shown. Show it:

1 the radial section through a cylindrical roller bearing according to a first embodiment of the invention,

2 the radial section through a cylindrical roller bearing according to a second embodiment of the invention and

3 the lower left area of 1 in an enlarged view.

In 1 is a rolling bearing 1 to see in the form of a cylindrical roller bearing, in the usual way an outer ring 2 , an inner ring 3 and arranged between the outer ring and inner ring rolling elements 4 in the form of cylindrical rollers. A cage 5 ensures the mounting and guidance of the rolling elements 4 ,

The cage 5 is presently not symmetrical, ie it has with respect to a center plane 11 of the camp 1 an imbalance. In the left area is the cage 5 provided with two conical surfaces, namely with a radially inner surface 6 and a radially outer surface 7 , The cone angle α of the radially inner surface 6 is about 10 °, with values between 10 ° and 20 ° are preferred. The cone angle β of the radially outer surface 7 is greater and is in the embodiment at about 30 °, with values between 20 ° and 50 ° are preferred.

The inner ring 3 has in radial section the illustrated S-shaped course, the best off 3 evident. From the front side 13 at the a small bevel 14 is attached, the radius of the inner ring increases in the axial direction A on the rolling elements 4 at first strong, then reaches a turning point 15 and then continues in the direction of the rolling elements 4 too shallow. In the end area 16 the profile runs in a tangential direction 17 from that corresponds to the axial direction A.

In cooperation with the radially inner surface 6 of the cage 5 This results in the following: The gap 8th that is between the inner ring 3 and the cage 5 remains, takes in the axial direction A on the rolling elements 4 out (ie towards the center of the warehouse) from the front 13 off gradually until he reaches the narrowest point 9 a minimum value, namely the distance a, reached. Because the radially inner surface 6 continues conical, the inner ring 3 however in the end area 16 in the axial direction A expires (tangential direction 17 ), the distance between inner ring increases 3 and cage 5 behind the narrowest point 9 again, ie the gap 10 has a radial extent that is greater than the narrowest point 9 ,

The distance a at the narrowest point 9 is very small, whereby the values can be between 0 mm and 2 mm. A value range between 0 mm and 0.8 mm is preferred. The above values are to be understood in the light of the fact that certain and not inconsiderable deviations in shape always result for the cage made of plastic, so that even with a distance a of 0 mm in operation a certain tolerance is always given, which is a distance of does not equal zero. In addition, the gap opens at the narrowest point 9 if it - which is inevitable during operation - to movements of the cage 5 in the axial direction A comes. Thus, even with a design of the distance a to 0 mm in operation, a certain opening of the narrowest point 9 so that this lubricant can get into the bearing interior.

The chosen size of the distance - between 0 mm and 2 mm - thus leads to the cage 5 optionally on the inner ring 3 with line contact starts and the cage 5 thereby on the inner ring 3 to be led. In normal operation and in particular at high speeds, however, there is a small distance a up to 2 mm, so that the cage 5 not on the inner ring 3 rubs. For this purpose, according to the construction, the distance a in the area of the narrowest point 9 usually designed between 0.1 to 0.5 mm. For installation of a cage 5 with line contact on the inner ring 3 it only occurs if, for example, an axial displacement of the cage 5 relative to the inner ring 3 takes place.

By the formation of the inner ring 3 and the cage 5 will reach that narrowest point 9 as well as the column arranged on both sides 8th and 10 form a kind of nozzle cross-section, which in conjunction with high speeds ensures that lubricant gets into the bearing interior. The provided from the front side lubricant - usually in the form of an oil mist - is due to the conical shape of the radially inner surface 6 due to the centrifugal force in the direction of rolling elements 4 conveyed in the axial direction A. The S-shaped design of the inner ring 3 in cooperation with the conical radially inner surface 6 Ensures that the lubricant is over the narrowest point 9 enters the warehouse.

As in 1 can be seen further, is only the left part of the cage 5 ie left of the middle plane 11 designed as explained. The right part of the cage 5 meanwhile has a radially inner surface 6 ' on, which runs in the axial direction A. This area 6 ' is located at a small distance b, which is also preferably between 0 mm and 2 mm, the section 12 of the inner ring 3 opposite, which also runs in the axial direction A.

Due to the asymmetry of the cage 5 Optionally, an increase in the pumping effect of the lubricant can be achieved. In addition, facilitates the running in the axial direction A radially inner surface 6 ' the assembly of the warehouse 1 , It is especially at insertion of a cage 5 from the left side into the space between outer ring and inner ring no undercut to overcome. However, it is also possible, in the event that a symmetrical formation of the cage 5 It is contemplated to overcome undercuts by heating or cooling the parts to be assembled to achieve dimensions required for assembly.

Furthermore, see that the cage 5 axially on both sides over the extension of the bearing rings 2 . 3 enough. The supernatant is indicated by the distance c. This supernatant c can be some percent of the axial width B of the rolling elements 4 be. As a result, the lubricant-collecting surface, ie the radially inner surface 6 , enlarged.

The solution according to 2 shows an embodiment in which the cage 5 concerning the middle plane 11 is executed symmetrically. Here, however, is in the axial direction of the rolling elements 4 to be rejuvenated gap 8th between the radially outer surface 7 and the outer ring 2 intended. Analogously, there is also a narrowest point here 9 in which the cage 5 from the outer ring 3 only a small amount a is spaced.

in the preferred application of the fast rotating spindle allows it the inventive concept that a preloaded storage is possible and that optimum lubrication is ensured. There are n × dm values from above 2.5 million easily reached.

1

roller bearing

2

outer ring

3

inner ring

4

rolling elements

5

Cage

6

radial inside surface

6 '

radial inside surface

7

radial external area

8th

gap

9

tightest Job

10

gap

11

midplane

12

section

13

front

14

chamfer

15

turning point

16

end

17

tangential direction

A

axially

r

radius

α

angle

β

angle

a

distance

b

distance

c

axial supernatant

B

axial Width of the rolling elements

Claims (15)

Roller bearing ( 1 ), with an outer ring ( 2 ), an inner ring ( 3 ) and between these arranged rolling elements ( 4 ), wherein the rolling elements ( 4 ) of a cage ( 5 ) are kept at a distance, the cage ( 5 ) at least one radially inner surface or radially outer surface ( 6 . 7 ) whose radius (r), as it progresses in the axial direction (A), onto the rolling elements ( 4 ) at least partially enlarged, characterized in that the cage ( 5 ) with its radially inner ( 6 ) Surface is formed and arranged so that it together with the inner ring ( 3 ) one as it progresses in the axial direction (A) on the rolling elements ( 4 ) to decreasing gap ( 8th ), wherein the distance (a) at the narrowest point ( 9 ) between cage ( 5 ) and inner ring ( 3 ) is between 0 mm and 2 mm, whereby the gap ( 10 ) between the surface ( 6 . 7 ) and the inner ring ( 3 ) behind the narrowest point ( 9 ) when proceeding in the axial direction (A) on the rolling elements ( 4 ) and the inner ring ( 3 ) has an S-shaped course in the radially outer region at least in a side region in the radial section. Rolling bearing according to claim 1, characterized in that the distance (a) at the narrowest point ( 9 ) between cage ( 5 ) and inner ring ( 3 ) or outer ring ( 3 ) is between 0 mm and 0.8 mm. Rolling bearing according to claim 1 or 2, characterized in that the radially inner or radially outer surface ( 6 . 7 ) is at least partially conical. Rolling bearing according to claim 3, characterized in that the cone angle (α) of the radially inner surface ( 6 ) is between 1 ° and 20 °. Rolling bearing according to claim 4, characterized in that the cone angle (α) of the radially inner surface ( 6 ) is between 7 ° and 13 °. Rolling bearing according to one of claims 1 to 5, characterized in that the cage ( 5 ) at mid-level ( 11 ) of the rolling bearing ( 1 ) is formed asymmetrically. Rolling bearing according to claim 6, characterized in that the cage ( 5 ) on either side of the middle plane ( 11 ) an axially extending radially inner surface ( 6 ' ) having an axially extending portion (FIG. 12 ) of the inner ring ( 3 ) is opposite at a distance (b). roller bearing according to claim 7, characterized in that the distance (b) between 0 mm and 2 mm, preferably between 0 and 0.8 mm. Rolling bearing according to one of claims 1 to 8, characterized in that the axial extent of the cage ( 5 ) is greater than the axial extent of the outer ring ( 2 ) and / or inner rings ( 3 ). Rolling bearing according to claim 9, characterized in that the axial projection (c) of the cage (c) 5 ) over the outer ring ( 2 ) and / or inner ring ( 3 ) between 3% and 25% of the axial width (B) of the rolling elements ( 4 ) is. roller bearing according to one of the claims 1 to 10, characterized in that it is a cylindrical roller bearing is. Rolling bearing according to one of claims 1 to 11, characterized in that the cage ( 5 ) on the outer ring ( 2 ) is guided. Rolling bearing according to one of claims 1 to 11, characterized in that the cage ( 5 ) on the inner ring ( 3 ) is guided. Rolling bearing according to one of claims 1 to 11, characterized in that the cage ( 5 ) on the rolling elements ( 4 ) is guided. Rolling bearing according to one of claims 1 to 14, characterized in that the cage ( 5 ) consists of plastic.