GB2258509A

GB2258509A - Rolling bearing for a swashplate mechanism

Info

Publication number: GB2258509A
Application number: GB9216359A
Authority: GB
Inventors: Gunter Neder; Walter Treibel
Original assignee: SKF GmbH
Current assignee: SKF GmbH
Priority date: 1991-08-06
Filing date: 1992-07-31
Publication date: 1993-02-10
Also published as: FR2680211A1; GB9216359D0

Abstract

A rolling bearing for a swashplate mechanism comprises two race rings (10, 12) and rolling bodies (16) disposed therebetween. The rings have raceways (14) on their radially extending surfaces facing each other. The axes (A1, A2) of rotation of the rings are inclined with respect to each other, the rolling bodies being balls (20, 22) of varying sizes. When the ring (12) is driven in rotation about its axis (A2), the assembly of balls (16) also rotates. The ring (10) is held against rotation and performs a wobbling motion in which any one location on the ring reciprocates axially as shown by arrows (24). Instead of the rolling bodies all being spherical the radial dimension thereof may be the same for all but the axial dimensions differ. <IMAGE>

Description

ROLLING BEARING FOR A SWASHPLATE MECHANISM This invention relates to a rolling bearing for a swashplate mechanism. A swashplate mechanism converts rotary motion into reciprocatory motion.

GB-A-2152618 (INA) discloses a radial ball bearing for a swashplate mechanism comprising radially inner and outer race rings and balls in the raceway grooves of the rings, in which the inner race ring is embedded in a plastics hub, the bearing axis being inclined to the hub axis. Although this construction allows the use of commercially available ball bearings, it still requires the moulding of the hub with the inner race ring embedded in it.

The invention provides a rolling bearing for a swashplate mechanism comprising two race rings and rolling bodies disposed therebetween, wherein the rings have raceways on their radially extending surfaces facing each other and the axes of rotation of the rings are inclined with respect to each other.

This construction does not require the use of a hub and allows the use of commercially available rolling bearing components. For example, the two rings can be those of a thrust ball bearing with raceways which are grooves of curved section, and the rolling bodies can be balls of different diameters.

For this particular construction, the largest ball and the smallest ball are positioned diametrically opposite each other and a graded set of balls are positioned between these two.

In another example of a construction according to the invention, with the same race rings, the rolling bodies may have the same radius of curvature as one another but different rolling diameters. In the construction using balls of different diameters the smaller balls are not guided precisely by the raceway grooves, whereas with the latter construction that disadvantage is overcome.

In the accompanying drawings, Figure 1 shows a longitudinal section through a rolling bearing for a swashplate mechanism having balls of different diameters; and Figure 2 shows a view along the axis of one ring of a rolling bearing for a swashplate mechanism having rolling bodies all with the same radius of curvature as one another.

The bearing shown in Figure 1 comprises two race rings 10 and 12 with raceway grooves 14, which are curved in section, are located on the radially extending surfaces of the rings and face each other.

Eight balls 16 of different diameters are disposed between the rings 10 and 12 in the raceway grooves 14 and are spaced from one another by a cage 18.

The axes A1 and A2 of rotation of the rings 10 and 12 are inclined with respect to each other so that, as shown the largest 20 of the balls 16 is at the top, and the smallest 22 of the balls is at the bottom of the drawing, the two balls being diametrically opposed to each other. The remaining balls have diameters gradually increasing in size from the smallest to the largest. The curvature of the raceway grooves 14 conforms to the radius of curvature of the largest ball 20.

In use, when the right hand ring 12 is driven in rotation about its axis A2, the assembly of balls 16 and cage 18 also rotates. The left hand ring 10 is held against rotation and performs a wobbling motion in which any one location on the ring reciprocates axially as shown by the arrows 24.

The bearing shown in Figure 2 comprises the same two rings as shown in Figure 1, but only one 10 is shown having the raceway groove 14 and also has the large ball 20 at the top of the drawing. Instead of the smaller balls this bearing has bodies 26 of rotation all having the same radius of curvature as one another, which is that of the large ball 20 and the raceway groove 14, but different rolling diameters. Consequently this bearing has the same running characteristics as a normal ball bearing since all the rolling bodies fit the curvature of the raceway groove. This bearing also includes a cage (not shown).

Claims

CLAIMS:

1. A rolling bearing for a swashplate mechanism comprising two race rings and rolling bodies disposed therebetween, wherein the rings have raceways on their radially extending surfaces facing each other and the axes of rotation of the rings are inclined with respect to each other.

2. A rolling bearing as claimed in Claim 1, wherein the raceways are grooves of curved section and the rolling bodies are balls of different diameters.

3. A rolling bearing as claimed in Claim 1, wherein the raceways are grooves of curved section and the rolling bodies have the same radius of curvature as one another but different rolling diameters.

4. A rolling bearing for a swashplate mechanism substantially as herein described with reference to and as shown in the accompanying drawings.