WO1985003749A1

WO1985003749A1 - Double row angular contact ball bearing with unilateral loading capacity

Info

Publication number: WO1985003749A1
Application number: PCT/DE1985/000047
Authority: WO
Inventors: Werner Jakob
Original assignee: Werner Jakob
Priority date: 1984-02-20
Filing date: 1985-02-20
Publication date: 1985-08-29
Also published as: EP0172204A1

Abstract

Double row angular contact ball bearing with unilateral loading capacity, characterized in that the ratio between the construction size and the importance of the loading capacity is more favourable than that of known ball bearings of which the loading capacity is smaller or the same size or which are larger and heavier for an identical loading capacity; furthermore, the present invention facilitates the fabrication and assembly of double row angular contact ball bearing. According to the invention, this is possible by means of a plurality of measures which are partly independent from each other, namely this is due to the fact that the shoulders (10, 11, 20, 21) of the ball bearing rings (1, 2) may be raised in the force direction (K) up to an optimum point and that the internal profile (12, 22) of at least one of the ball bearing rings (1, 2) comes out, from the peak point (41) of the ball (30, 40) which are adjoined thereto, almost parallel to the external profile (13) of the ball bearing rings. Both rings (1, 2) may thus be each fully provided with balls (30, 40) which may then be pushed against each other. Independent characteristics of what precedes but leading to the same aims, the diameters of the ball bearing paths and/or the balls may be different; these measures enable to obtain a more compact double row angular contact ball bearing with unilateral loading capacity.

Description

Double angular contact ball bearing resilient

The invention relates to a single-sided loadable double angular contact ball bearing with the balls of the bearing between them, including races, on the shoulders of which the balls are supported when force is applied.

Since there has not yet been a double angular contact ball bearing that can be loaded axially and radially on one side, two single sided angular contact ball bearings have hitherto always been combined to form a tandem bearing, so that each in the two opposite directions of force

10 there are two high shoulders on which the balls can be supported.

This solution to the problem described above has not been changed for over two decades, as can be seen from the catalogs in which the companies offer these double angular contact ball bearings. Examples include the SKF catalog from March 1964 (Dd 4000) and 1982, the FAG catalogs from 1979 and 1983 (41125 DA), in which even two pairs of such individual bearings are arranged one after the other, each pair of bearings for a different force ^Ä en ^υ πchtung is provided.

The last-named catalog in particular shows at first glance that such a double angular contact ball bearing is extremely space-consuming. However, this is not the only disadvantage of these well-known and practically identical applications everywhere. ten forms of bearings, but the expert knows the circumstances of coupling two individual bearings so that the balls run smoothly.

The individual bearings that come from a series are in the

Usually evenly adjusted to the required contact angle, which can move between about 15 and 45 °, depending on how the loads that the bearing has to absorb affect the bearing.

Now every practitioner knows that there are plus and minus tolerances in every production; This is particularly important when machining has to be carried out, which is the case with the races of a bearing. So before you couple two single bearings with each other, they have to be measured very precisely, which at least still has to be checked by people today. This applies not only to the inside but also to the outside contours. It does not need to be explained in more detail that this is a very complex and costly procedure; because you cannot find a matched pair, you have to regrind them, although of course additional rejects cannot be avoided.

In addition, there is another disadvantage that full filling of these individual bearings requires filling grooves or the possibility of eccentric displacement of the races, all measures which make the manufacture and assembly of such bearings considerably more difficult.

These drawbacks have been known to those of skill in the art for decades and it cannot be assumed that none of them would have tried to remedy these drawbacks at one time or another. In practice, however, no progress has yet been discernible.

Not even the long-established fact that there are double angular contact ball bearings with 0 and X force directions, in which one of the races is common to both ball raceways and the other is shared, has not given rise to ideas that have the same direction Double angular contact ball bearings are applicable.

This solution is shown in the FAG catalog 1979 on page 93 and a large number of patents, for example DE-OS 1 625 605, in which it is emphasized on page 1 that it is "essential" that both rings are completely coaxial.

Even if this solution were to be applied to rectified bearings of the type relevant here, one would still have to accept a number of disadvantages: the parts of one ring have to be adapted to one another or the other race, regrinded, etc. These too and measures known from other bearings cannot be applied to the tandem bearings in the same direction.

The object of the invention is to develop a new tandem double angular contact ball bearing which simplifies the production and assembly of the bearings and which improves the relationship between the bearing volume and the load carrying capacity.

The invention achieves this by combining several features which are known per se in other types of bearings. The basic feature is that both races are in one piece, a fact that is the case with bearings with filling grooves or the like. is known. This measure therefore enables a very narrow and low construction, especially when the diameters of the ball raceways are different; because then the ball raceways can move closer together, a feature that is also known in other bearings - also with balls of different sizes - but which is particularly important in tandem bearings. These one-piece races not only bring a compact design, but they also have the particular advantage that both races can be ground in with one another so that their apex lines run absolutely parallel and are precisely coordinated with one another. This applies to both raceways of both races. To be able to do this, two further features are required, which are also known for other bearing types, but are particularly useful in combination with the one-piece races.

If the tandem bearing has to absorb particularly large radial and axial forces, particularly high shoulders are required in the direction of force, which in these bearings are applied on one side or are aligned. The shoulders follow the second characteristic

10 achieve the invention in that they are designed so that they encompass the ball circumference up to about 45 * of the vertical ball diameter, in both rows of balls.

This in turn would complicate the filling of the double angular contact ball bearing and its assembly, unless the third feature of the invention made this possible. According to this feature of the invention, at least one of the raceway ends opposite these load-bearing shoulders runs approximately parallel to the raceway outer edge 20 from the apex of the balls assigned to them or it ends in the region of this apex.

It is thereby achieved that one of the races with the balls of both or both races with the balls can or can each be fitted with a ball raceway and then the races can be pushed into one another.

By means of the one-piece races and the marked run-out of the rider (s), a one-piece tandem bearing can therefore be produced which can be fully equipped and does not require 30 filling grooves or other auxiliary means.

For the purposes of the invention, the raceway ends can run completely parallel to the bearing outer contour, but they can also be designed to slope slightly or end in the region of the ball vertex 35.

If such a bearing is to be delivered assembled, the usual loss protection can be provided. These and other features of the invention are highlighted in the claims and shown schematically in the drawings; show it

1 shows the basic structure of a bearing according to the invention,

2 shows an embodiment with differently sized race ring diameters,

3 shows an embodiment with race ring diameters of different sizes and balls of different diameters,

4 shows the assembly of a bearing in which the ball races are fitted with balls separately from one another and

5 shows the assembly of both ball raceways in a ball race.

The same parts are provided with the same reference symbols in all the figures, even if they are designed somewhat differently in details.

1 shows a double angular contact ball bearing which is generally loadable on one side and in which the diameter of the ball raceways 3, 4 and that of the balls 30, 40 are the same size. The letter K indicates the direction of force.

The outer race 1 has two shoulders 10, 11, which extend almost to the center of the balls 30, 40, so that they overlap their circumference by approximately 45% of the perpendicular diameter, i.e. almost to the horizontally running ball diameter, that is achieve the optimum shoulder height to be demanded; because 50% or more would be possible with the construction according to the invention, but would not bring any additional advantages.

Just as the shoulders 10, 11 can be larger than they are shown, they can also, depending on the application be lower. In this respect, the 45% is only a guideline for optimal louse recordings; Shoulder heights of up to 25% or slightly less are therefore possible within the scope of the invention.

The inner contour of the free end 12 of the race 1 runs parallel to the outer contour 13 of this race 1 and starts at the point 41 of the balls 40, so that the race 1 can be pushed over the balls 40 from the left.

The race 2 can be mirrored identical to the race

1, that is, the high shoulders 20, 21 and the same outlet at 22 as in 12. In the exemplary embodiment in FIG. 1, the inner contour 22, however, slopes downward from the apex 31 of the balls 30, that is to say not completely parallel to the outer contour 23 .

In this figure it is also indicated at 14 and 24 how the double angular contact ball bearing behaves under load. The balls 30, 40 put on the bearing at 15 and 25, respectively, so that a small annular gap forms at 14, 24, which is exaggerated in this figure. The ball cages are omitted in the upper part of this figure, because there are also other options for fitting the races with balls in such a way that they adhere closely to one another in the races.

FIG. 2 shows a variant of the embodiment according to FIG. 1. The races 1, 2 are no longer completely identical or congruent in mirror image as far as the course of the inner contours are concerned. The shoulders 10, 11 and 20, 21 are also present, but designed differently; the reason for this is explained with reference to FIG. 5. The inner contour at 12 also runs parallel to the outer contour 13, but it starts below the apex 41 of the balls 40; this is also explained further in the explanation of FIG. 5.

The race 2 is designed differently than the race 1. Its free end 22 is not led to the end of the bearing, but shorter, which saves material and weight. 1 is that the diameter of the two ball tracks 3, 4 is of different sizes. This ensures that the bearing is more compact, the ball races 3, 4 can be closer together. Since the shoulders 10, 11 and 20, 21 are unequally high in this embodiment, the load-bearing capacity of the bearing is somewhat different than in the embodiment according to FIG. 1, but it is also larger here than in the known double-angular contact ball bearings which can be loaded on one side , the relationship between size and load capacity is taken into account.

FIG. 3 shows a variant in which the diameters of both the ball tracks 3, 4 and that of the balls 30, 40 are different in size; the ball raceway 4 has a larger diameter than the other and its balls 40 have a smaller diameter than the balls 30. This is one of the optimal designs of the double angular contact ball bearing according to the invention, other variants are possible. Thus, in one case it can be advantageous not to make only the diameter of the balls, on the other hand, that of the raceways different or ^* vice versa, or to arrange the balls of smaller diameter in the race of smaller diameter.

The last two figures clearly show the advantages of the invention; For a better overview, the individual parts are shown drawn apart.

4 shows a bearing according to the invention, in which both ball races 1, 2 can be fitted with balls 30 and 40 separately from one another, it not being essential to the invention in which of the possible variants of the inventive concept this type is chosen.

The two races 1, 2 are congruent in mirror image, the race diameter is not the same, the ball diameter is the same size. In this type of installation, the inner contours of 12 and 22 must run from the apex 31, 41 of the balls 30, 40 parallel to the outer contour or slightly sloping so that the races of one ball raceway are pushed over the balls of the other can be. If the ball races 1, 2 are equipped with the balls 30, 40, they can either be pushed together outside the machine parts so that a bearing unit is created, which can either be placed on a shaft and inserted into a housing with it, or into a housing is insertable. However, it is also possible to insert the outer race 1 with its balls into a housing and to place the inner race 2 with its balls on a shaft and to insert both parts together into the outer race 1.

In the embodiment according to FIG. 5, both ball rings 30, 40 are inserted into one of the race rings 1 or 2, whereby they are held in the race ring by the somewhat overlapping inner contour of the race ring end 12. Then the other race is inserted. Here, too, all the types of installation already indicated are possible.

2 and 5, then the inner contour 12 of the one inner race overlaps the apex of the balls.

Claims

Double angular contact ball bearing resilient

1. Double-sided loadable double angular contact ball bearing with the balls of the bearing between enclosing races, on the shoulders of which the balls are supported under the action of force, characterized by the combination of the following. known characteristics

a) the two races (1, 2) are in one piece,

b) the shoulders (10, 11 or 20, 21) of the ball races lying in the direction of the acting force (K)

(1, 2) encompass the circumference of the ball up to about 45% of the vertical ball diameter,

c) at least one (12 or / and 22) of the raceway ends opposite these shoulders (10, 11 or 20, 21)

(12 or / and 22) runs from the apex (31 or / and 41) of the balls (30, 40) assigned to them to the outside approximately parallel to the outer contour (13, 23) of the races (1, 2).

2. Double angular contact ball bearing according to claim 1, characterized in that the diameter of the ball raceways (1, 2) is of equal size in a manner known per se.

3.. Double angular contact ball bearing according to claim 1 or 2, characterized in that, in a manner known per se, the diameter of the balls (30, 40) of both ball raceways (3, 4) is of the same size.

4. Double angular contact ball bearing in particular according to claim 1 or 3, characterized in that the diameter of the Kugel¬ raceways (3, 4) is of different sizes.

5. Double angular contact ball bearing according to one or more of claims 1, 2 and 4, characterized in that the diameter of the balls (30, 40) of the two ball tracks (3, 4) is different in size.

6. Double angular contact ball bearing according to one or more of claims 1 to 5, characterized in that both the inner

(2) how the outer (1) race are each in one piece.

7. Double angular contact ball bearing according to one or more of claims 1 to 6, characterized in that both races (1,

2) are congruent in mirror image.

8. Double angular contact ball bearing according to one or more of claims 1 to 7, characterized in that all of the shoulders (10, 11 or 20, 21) which absorb the load are of equal height.

9. Double angular contact ball bearing according to one or more of claims 1 to 8, characterized in that the inner contour of both ball races (1, 2) in their unloaded parts

(14, 24) from the apex (31, 41) of the respectively assigned balls (30, 40) run approximately parallel to the outer contour (13, 23) of the ball races (1, 2).

10. Double angular contact ball bearing according to one or more of claims 1 to 8, characterized in that the inner contour of one of the ball races (1, 2) in its unloaded part (14 or 24) to a small extent soaks the vertex (31 or 41) of the associated Balls (30 or 40) overlaps and then runs approximately parallel to the outer contour (13 or 23) of the ball races (1, 2).

11. Double angular contact ball bearing according to one or more of claims 1 to 10, characterized in that the balls (30, 40) of both ball raceways (3, 4). provided by means of cages (5) can be inserted into the ball races (1, 2).

12. Double angular contact ball bearing according to one or more of claims 1 to 11, characterized in that the inner race

(2) on the unloaded outlet (23) has a different thickness than the outer race (1) on its outlet (13).