DE4322729C1 - Rotary bearing arrangement having a combination of a roller bearing and a sliding bearing - Google Patents

Abstract

The invention relates to a combination of a roller bearing and a sliding bearing, in which the roller bearing is assigned a sliding bearing with a predeterminable or adjustable friction. This bearing combination is suitable, in particular, for mounting steering knuckles and the like on motor vehicles. By means of a spring which pushes the sliding-bearing elements towards one another, it can be achieved with a corresponding spring characteristic that the sliding friction only changes insignificantly, even in the case of wear of the bearing parts.

Description

The invention relates to a pivot bearing arrangement Rolling-plain bearing combination, the plain bearing with specified barer or adjustable friction works, which Rolling bearings separated from each other by the rolling elements Has raceway rings and as a plain bearing to the bearing axis coaxial slide ring on a raceway ring held bar and with adjustable force against one other sliding surface associated with the other race ring can be tensioned is.

Rolling bearings have one even at low speeds low friction. At higher speeds, however Noises and vibrations occur which are caused by more or less minor out-of-roundness of the rolling elements or unevenness in their careers.

At low speeds, plain bearings have a right high friction because the sliding surfaces in this condition usually lie directly on top of each other. At higher In contrast, speeds form between the sliding surfaces a film of lubricant, which is a direct touch the sliding surfaces prevented from each other, so that overall a very low friction - primarily caused due to internal friction in the lubricant - occurs. About that  the lubricant film also has a vibration-damping effect.

The formation of the lubricant film also means that the sliding surfaces at higher relative speeds take a slightly different position relative to each other than at low speeds. In the case of a radial Shaft bearing, this means that the shaft at very low speeds a comparatively strongly eccentric Position in the radial bearing, while the shaft higher speed increasingly towards the warehouse center is pushed.

This effect can occur, for example, when axially side by side arranged rolling and sliding bearings of a shaft are used become. A roller bearing arranged with play is so be measure that always a direct touch of the sliding surfaces of the plain bearing is prevented. This joins low speeds only the low friction of the rolling in stock. As soon as higher speeds are reached, a stable lubricant forms in the plain bearing film pushing the wave towards the warehouse center whereby the roller bearing is practically completely relieved. Accordingly, only occurs at higher speeds the low friction of the lubricant film, which can have a vibration-damping effect at the same time.

In this regard, the publication "Mechanical engineering", 5th year, issue 4, April 1956, Pages 177 to 187, and on DE-OS 15 25 146 to get expelled.  

Furthermore, it is in rolling bearings, their rolling elements are guided by cages, known to the cage Slowing down the rotary movements of the bearing somewhat by friction, a sliding movement around the rolling movement of the rolling elements to overlay. Because of this sliding movement forms a trag between the rolling elements and their raceways capable lubricant film, which at higher speeds a direct contact between the rolling elements and counteracts the careers. The rolling elements "floating" on a lubricant film. Behaves with it the rolling bearing is similar to one at higher speeds Bearings.

In this context, the DE-GM 19 32 924 as well the DE-PS 4 64 649 are referred.

In addition, roller-slide bearing combinations are then a set when the occurring rotation or Relativge speeds are low, but storage from would be too low friction due to rolling bearings.

Especially when mounting kingpin Motor vehicles are therefore different Kombina tion of plain and roller bearings known. For example can the radial bearing of the kingpin in essence made exclusively by rolling bearings, while partially through the axial bearing of the kingpin Rolling and partly by plain bearings is made.

In this context, DD-PS 1 04 263 and the publication "ATZ Automobiltechnische Zeit pamphlet "83 (1981) 12, pages 631 to 636  from which it emerges that in the aforementioned application slide bearings as an upper axial bearings are used.

From DE 30 19 857 A1 is also for Bearing of kingpin suitable rolling-slide bearing combination known, in which the rolling bearing as Thrust bearing and the plain bearing as a radial bearing forms are.

Furthermore, DE 37 25 972 A1 shows a roller-slide bearing combination which is particularly suitable for the rotary mounting of the nacelle of wind power plants, in which the roller bearing is designed as a ball bearing suitable for absorbing axial and radial forces, on the raceway rings of which friction elements are arranged . In this connection (cf. FIG. 4) it can be provided in particular that a V-groove open to the other raceway ring is arranged on one raceway ring, the width of which can be changed by adjusting screws. This allows a slide ring received by the V-groove to be more or less clamped against the other raceway ring in order to generate an adjustable friction force.

The object of the invention is now, in particular for the storage of steering knuckles u. The like. On motor vehicles to show a suitable combination of roller and slide bearings, at which is particularly easy to adjust the friction force leaves.

This object is achieved in that the adjustable slide ring on a raceway ring axially  arranged screw-adjustable and relative to this The raceway ring can be locked in a rotationally fixed manner by means of locking means and that on the other raceway ring a counter slide surface-forming counter slide ring non-rotatable, but axially movably supported and against by means of a spring arrangement the aforementioned slide ring is tensioned.

The spring arrangement is expediently as a plate spring trained.

Because of this design, the bearing friction is easy adjustable, reproducible value, which if necessary is changeable or correctable and with appropriate Identification of the spring arrangement only insignificant even when worn Lich changes.  

In addition, the plate spring and the slide ring and the counter slide ring also the function of a seal of the rolling bearing to the outside or as a carrier Serve as a seal.

The invention is based on one in the drawing illustrated advantageous embodiment explained.

The only figure shows an axial section of one Thrust bearings.

The bearing arrangement, which is rotationally symmetrical with respect to an axis 1, has, in a manner known for axial ball bearings, an upper and a lower ball race ring 2 and 3 as well as spherical balls 4 rotating in annular, groove-shaped tracks of these ball race rings 2 and 3 .

The lower ball race ring 3 has a radially outside of the ball raceway, in cross section z. B. rectangular annular groove 5 , the open side of which faces the ball race ring 2 .

In this annular groove 5 is a corresponding annular spring, for. B. a plate spring 6 , which is tensioned against a slide ring 7 , which is axially displaceable but non-rotatably supported on the ball race ring 3 . For this purpose, the sliding ring 7 engages with an external toothing in an internal toothing of an annular web 8 formed on the ball raceway ring 3 . Instead, the ring 7 can also have a radial fixing pin which engages in an axial groove on the ring 3 .

On the ball race ring 2 , a counter sliding ring 9 is fixed in rotation, but axially adjustable, against which the sliding ring 7 is tensioned by means of the plate spring 6 .

For axial adjustment of the counter slide ring 9 on the ball raceway ring 2 , the counter slide ring 9 has on its inner circumference a thread which interacts with a corresponding external thread on the ball raceway ring 2 . By locking means, not shown, the counter sliding ring 9 can be held on the ball race ring 2 in the one axial position in a rotationally fixed manner.

With relative rotations between the ball race rings 2 and 3 , the relatively low rolling friction of the balls 4 in the ball raceways and additionally the adjustable frictional resistance between the slide ring 7 and the counter slide ring 9 must then be overcome.

The ball bearing parts - ie the balls 4 and their ball races - are closed radially outwards by the plate spring 6 and the slide ring 7 and the counter slide ring 9 .

Claims (6)

1. Pivot bearing arrangement with roller-slide bearing combination, the slide bearing of which can be set with a predeterminable or adjustable friction, the roller bearing having raceway rings which are separated from one another by the roller elements, and as a slide bearing, a slide ring coaxial with the bearing axis on an raceway ring is adjustably held and with adjustable force against one of the other sliding surface associated with the other raceway ring can be tensioned, characterized in that the adjustable sliding ring ( 9 ) is axially screw-adjustable on one raceway ring ( 2 ) and can be locked in a rotationally fixed manner relative to this raceway ring ( 2 ) by locking means, and in that the other raceway ring ( 3 ) has a counter slide ring ( 7 ) is non-rotatable, but is axially movable and is tensioned by means of a spring arrangement ( 6 ) against the aforementioned slide ring ( 9 ). 2. Pivot bearing arrangement according to claim 1, characterized in that an annular plate spring ( 6 ) is arranged as a spring arrangement. 3. pivot bearing arrangement according to claim 1 or 2, characterized in that the spring arrangement ( 6 ) has such a spring characteristic that the sliding friction changes only slightly with wear of the sliding elements. 4. pivot bearing arrangement according to one of claims 1 to 3, characterized, that the plain bearing seals the rolling bearing to the outside. 5. pivot bearing arrangement according to one of claims 1 to 4, characterized, that the plain bearing is sealed to the outside. 6. Pivot bearing arrangement according to one of claims 1 to 5, characterized in that the adjustable sliding ring ( 9 ) is accessible from the radially outside.