DE102006060680A1 - Rolling bearings for a radial piston pump - Google Patents

Abstract

The invention relates to a rolling bearing for a radial piston pump (5) with an inner ring (2) and an outer ring (3) and arranged between these bearing rings rolling elements.
To create a rolling bearing for a radial piston pump, which has a long service life, is suitable for high radial forces and can absorb axial forces, the invention provides that the rolling bearing is designed as a ball roller bearing (1), the rolling elements as ball rollers (4), respectively two flattened from a spherical base shape deviating and arranged parallel to each other side surfaces (6, 7) are formed.

Description

Field of the invention

The The invention relates to a rolling bearing for a radial piston pump with an inner ring and an outer ring as well as between These bearing rings arranged rolling elements.

Background of the invention

From the German Patent Specification No. 311,317 is a roller bearing is known, represent the roles of the basic shape of a Umdrehungsellipsoids symmetrically cut discs and roll on grooved outer and inner rings. The rollers can be advantageously introduced into the camp in that they are tilted between the races pushed and then rotated into their working position. Since the roller circumference is spherical, this rotation can be done without resistance.

Another radial ball bearing with spherical washers is in the DE 43 34 195 A1 shown and described. When filling the bearing with the spherical discs and these are introduced axially to the bearing between the inner and outer ring.

If her center is at the height the runway axis is located, the spherical discs are rotated by 90 °, so that their spherical surface can roll in the runways.

For vehicle brake systems with a pump unit ( DE 199 58 927 C1 ) or anti-lock braking systems (ABS) or hydraulic brake slip control systems ( DE 196 53 895 A1 ) are used for storage of the rotatable components of the pump usually designed as a ball bearing and / or needle roller bearings.

Of the Use of a conventional ball bearing in such a pump unit has opposite one Needle roller bearings have some advantages, such as the smaller axial space, the lower friction during operation, the lower noise emission and the ability also axial forces transferred to a certain extent to be able to. The eccentric ball bearings currently in use with or without having eccentric bearing inner ring in pumps of ABS systems However, the disadvantage that this at given diameter due too low load rating and because of too small lubricant space in Warehouse for increased Load and / or life requirements are not suitable.

Such increased Requirements can For example, arise from the fact that with the same pump also still supplies other, a hydraulic pressure using vehicle systems should be. Such vehicle systems may include, for example, a traction control system, an automatic acting on the service brakes of the vehicle Distance control system or a parking brake system.

As In all applications in vehicle construction is also used by a pump for a braking system and their pivot bearing required that this axially possible short builds and comparatively large radial forces and to a lesser extent also axial forces at long life can.

Object of the invention

In front In this background, the invention is based on the object at a radial piston pump a rolling bearing to use, which has a comparatively long life, for high Radial forces suitable is and can transmit axial forces to some extent.

Summary of the invention

Of the Invention is based on the finding that a ball roller bearing across from a conventional ball bearing with otherwise the same dimensions a larger lubricant space has, which is therefore filled with a larger amount of lubricant. This ensures a lifetime extension at a relatively small axial space requirement in a radial piston pump. In addition, you can transmitted by the ball rollers to some extent and axial forces and these have a lower friction in operation than Needle bearings.

The The invention is therefore based on a rolling bearing for a radial piston pump an inner ring and an outer ring and arranged between these bearing rings rolling elements. Besides that is provided that the rolling bearing designed as a ball roller bearing is, whose rolling elements as ball rollers each with two flattened from a basic spherical shape deviating and mutually parallel side surfaces are formed. By This structure is achieved in particular that for the rolling elements a smaller axial space than conventionally needed becomes. The axial space thus obtained is preferred as an additional lubricant space used. The improved lubricant or grease supply allowed a lower friction, which significantly increases the service life.

In an advantageous embodiment the ball roller bearing according to the invention is provided that the inner ring is a centric or eccentric Having circumferential geometry, wherein the entire rolling bearing is designed as an eccentric rolling bearing.

there can be provided that the inner ring is a centric or a Has eccentric circumferential geometry on its inner circumference, or that the centric inner ring on an eccentric shaft approach a pump shaft is arranged.

By the use of ball rollers in the rolling bearing is the higher one Load rating of the rolling bearing assembly according to the invention the pump can be realized. When proposed ball roller bearing for a radial piston pump is due to the higher Number of balls or by the smaller pitch, the load capacity elevated. In addition, due to the enlarged lubricant space extended load and life requirements compared to known ball bearings, for example ESP, distance control, parking brake systems or the like, can be fulfilled.

Advantageous It is also when the inner ring and the outer ring facing each other guide rings made of a wear-resistant Material are provided whose facing the ball rollers sides are adapted to the spherical geometry of the ball rollers. The guide rings have a high axial and radial load capacity. Especially the radial load capacity of the ball roller bearing is thereby improved, that oscillation of up to 100% is possible, with the conventional Ball bearings usual Point contact by a line contact in the ball roller bearing is replaced.

Especially Cheap is the use of the ball roller bearing according to the invention for the storage of rotatable components of a pump, for example in a radial piston pump an anti-lock braking system (ABS). Here are such pump designs preferred, which have at least one pump tappet, which at a eccentric pump shaft or on an eccentric shaft approach or on an outer ring the ball roller bearing of the radial piston pump rests radially. To this pump shaft support radially better to be able to it is useful if axially opposite the ball roller bearing a second bearing is arranged. This second roller bearing can also be a ball roller bearing or as a needle bearing or Cylindrical roller bearings may be formed, for example, centric arranged to the pump shaft and eccentric to the eccentric shaft approach is.

Brief description of the drawings

The Invention will be described below with reference to the accompanying drawings on an embodiment explained in more detail. In this demonstrate:

1 3 shows an illustration of the ball roller bearing according to the invention in an axial section, arranged on an eccentric shaft extension of a radial piston pump,

2 a frontal plan view of the ball roller bearing, and

3 a radial piston pump with a ball roller bearing according to 1 respectively. 2 ,

Detailed description the drawings

The in the 1 to 3 illustrated bearing assemblies show a wave 12 a radial piston pump 5 with a wave approach 11 whose longitudinal axis 22 eccentric to the longitudinal axis 16 the wave 12 is aligned.

On the wave approach 11 is a ball roller bearing 1 arranged, with a tight on the shaft approach 11 sitting inner ring 2 and an outer ring 3 , between which in raceways of the two bearing rings 2 . 3 rolling ball rollers 4 arranged and from a cage 23 are guided. The ballscrews 4 each have two of the spherical shape deviating flattened and arranged parallel to each other side surfaces 6 . 7 on, which compared with full-spherical rolling elements an axially enlarged lubricant space 10 is formed. The larger lubricant reservoir compared to conventional ball bearings extends the service life of this rolling bearing.

On the radial outside of the outer ring 3 or on the shaft approach ( 3 ) act pump tappets 8th and 9 that during a rotary motion of the shaft 12 due to the eccentric arrangement of the shaft extension 11 be moved radially outward against the force of a respective spring, not shown here, and thus promote pump oil or a brake fluid in associated pump cylinders in a known manner.

As 1 in the lower half shows are in the inner ring 2 and the outer ring 3 respectively radially facing guide grooves 14 incorporated the tracks for the ball rollers 4 form and therefore on their to the ball rollers 4 pointing side to the spherical geometry of the ball rollers 4 adapted to achieve the greatest possible osculation between them.

The inner ring 2 is according to 1 with a centric opening 13 performed, which at the eccentric shaft approach 11 the wave 12 is attached. 2 on the other hand shows an eccentric inner ring 2 with over its circumference different radial thickness and therefore eccentric to the outer circumference formed central opening 13 ' with this on a centric shaft approach 11 sitting.

As in 3 is shown, includes the radial piston pump 5 for an anti-lock system an electric motor drive 17 with one on the pump housing 24 attached stator 15 and one on a motor shaft 19 attached rotor 18 , The wave approach 11 or the wave 12 is with the motor shaft 19 rotatably connected or formed integrally therewith. At the free end of the motor shaft 19 is centric to the motor shaft 19 and to the wave 12 a shaft end piece 20 formed, which by means of a second bearing 21 in the pump housing 24 is supported. This second camp 21 is designed as a needle bearing.

According to the in 3 The embodiment shown operates the eccentric shaft piece 11 during a rotary movement of the motor shaft 19 of the electric motor, the pump tappets 8th and 9 to pump a brake fluid into the anti-lock system.

1

Spherical roller bearings, roller bearing

2

inner ring

3

outer ring

4

Ball roller, rolling elements

5

Radial piston pump

6

side surface

7

side surface

8th

pump plunger

9

pump plunger

10

lubricant space

11

shaft extension

12

wave

13

Opening of the inner ring

13 '

Opening of the inner ring

14

guide grooves

15

stator

16

Longitudinal axis of the shaft 12

17

electromotive drive

18

rotor

19

motor shaft

20

shaft end

21

second camp

22

longitudinal axis of the wave approach

23

Cage

24

pump housing

Claims (11)

Rolling bearings for a radial piston pump ( 5 ) with an inner ring ( 2 ) and an outer ring ( 3 ) and arranged between these bearing rings rolling elements, characterized in that the rolling bearing as a ball roller bearing ( 1 ) is executed, the rolling elements as ball rollers ( 4 ) each with two deviating from a spherical base shape and flattened parallel to each other side surfaces ( 6 . 7 ) are formed. Rolling bearing according to claim 1, characterized in that the inner ring ( 2 ) has a centric or eccentric circumferential geometry. Rolling bearing according to claim 2, characterized in that the central inner ring ( 2 ) on an eccentric shaft approach ( 11 ) of a wave ( 12 ) is arranged. Rolling bearing according to claim 2, characterized in that the eccentric inner ring ( 2 ) on a centric shaft extension of a shaft ( 12 ) is arranged. Rolling bearing according to at least one of claims 1 to 4, characterized in that the inner ring ( 2 ) and the outer ring ( 3 ) with mutually facing guide grooves ( 14 ) are provided, whose to the ball rollers ( 4 ) facing sides of the spherical geometry of the ball rollers ( 4 ) are adjusted. Use of a ball roller bearing ( 1 ) according to at least one of claims 1 to 5 in a pump. Use according to claim 6 in a radial piston pump ( 5 ) of a motor vehicle. Use according to claim 7 in a radial piston pump ( 5 ) of an anti-lock braking system (ABS). Use according to at least one of claims 6 to 8 in a radial piston pump ( 5 ) with at least one pump tappet ( 8th . 9 ) acting on an eccentric shaft ( 12 ) or an eccentric shaft approach ( 11 ) or on an outer ring ( 3 ) of the ball roller bearing ( 1 ) bears radially. Use according to at least one of claims 6 to 9 in a radial piston pump ( 5 ) with a second bearing ( 21 ) centered on the shaft ( 12 ) and eccentric to the eccentric shaft approach ( 11 ) is arranged. Use according to at least one of claims 6 to 10 in a radial piston pump ( 5 ) with an electromotive drive ( 17 ).