DE102006057512A1 - Rolling bearing cage - Google Patents

Abstract

The invention relates to a roller bearing cage (01) for rolling bearings with a shaft diameter greater than 100 mm. The cage consists of a profiled sheet steel with a plurality of rolling elements pockets (06) for receiving rolling elements (13), which are formed by two parallel outer rings (02) and between the outer rings (02) extending webs (03). The webs (03) each have two outer axially parallel web portions (07) and an inner axially parallel web portion (08), which are interconnected by obliquely extending portions (09). According to the invention, the steel sheet has a thickness which is less than 0.1 times the Wälzkörperdurchmessers.

Description

Field of the invention

The The invention relates to a sheet metal cage for large rolling bearings, especially for roller bearing for shaft diameter greater than 100 mm, according to the preamble of claim 1.

roller bearing generally consist of two bearing rings with integrated raceways. Between the bearing rings rolling elements are arranged, the to roll on the careers. Be as rolling elements Balls, cylindrical rollers, needle rollers, tapered rollers and barrel rollers used.

One usually as well provided rolling bearing cage holds the rolling elements in even distance to each other and prevents them from touching each other. at Needle bearings and bordlosen spherical roller bearings provides the rolling bearing cage in addition to the right one Position of the rolling body axis. Are bearings collapsible, holds the rolling bearing cage the Rolling elements together and thereby facilitates the installation and maintenance of the bearings.

For special Applications are also full-spherical, full-complement and full-needle Rolling bearings for Commitment. Such cageless roller bearing however, are not affected by the present invention.

roller bearing have to in the most diverse applications high loads, centrifugal forces and Safely absorb accelerations and enable high speeds. These may come in some circumstances Vibrations of storage during the Rotation around its own axis with strong radial accelerations, which burden especially the bearing cages. Choosing the right cage design plays a decisive role.

Solid cages exist It is made of brass, steel, hard tissue and other materials.

at huge roller bearings (Shaft diameter greater than 100 mm) are usually used according to the prior art brass solid cages. The material has good machinability and good contact properties to the most commonly used steel rolling elements. The disadvantage here is that the brass has a relatively low material rigidity, which is why wide cage bars necessary for stabilization, which in turn is the maximum number the rolling elements and thus reducing the load capacity of the bearing.

strongly There are also cages or intermediate pieces made of thermoplastic materials, in particular those made of glass fiber reinforced polyamide. Across from a full complement bearing is in this embodiment only one rolling element less used, therefore, a relatively high load rating is achieved. By relatively large However, these cages are tolerances in the production of plastic spacers only for Small to medium sized bearings suitable.

Known are for larger bearings also called brass disc cages, at which the rolling elements in a perpendicular to the bearing axis aligned disc with bulges are arranged. It will be a narrow Wälzkörperteilerteilung and thus a high load capacity reached. The disadvantage of this cage type is that the bearing outer ring must be shared in order to achieve a stable leadership of the cage.

In the metal cages M or W, and A or V profiles and S-shaped cage structures are known. The standard material for sheet metal cages is steel, for some applications also brass. Sheet metal cages are primarily used for smaller to medium sized rolling bearings. Such sheet cages are made, for example EP 1 262 256 B1 . DE 195 29 379 A1 or DE 31 30 610 A1 known.

From the DE 10 2004 028 376 A1 is a sheet metal cage known, which is also used for larger bearings. This sheet-metal cage extends between the rolling elements exclusively in an area directed outwards from the roller pitch or inwards. The cage webs have a trapezoidal cross-section. This sheet metal cage is made in one piece, the rolling elements are not self-holding or captive arranged in the cage. The latter complicates the mounting of the bearing and the maintenance considerably.

races and rolling elements are predominantly made through hardened Chrome steel. For special conditions of use are also bearings made of stainless steel, Ceramic, or so-called hybrid bearings used. At the hybrid warehouses the bearing rings are made of steel, the rolling elements are made of ceramic. For one especially quiet rolling elements are also turned on Plastic or glass used.

Especially at big roller bearings (Shaft diameter greater than 100 mm) there is a requirement to realize a high load rating.

Based on the previous use of solid brass cages for bearing sizes from 100 mm shaft diameter, it is an object of the invention to reduce the web widths of the cages to accommodate more or larger rolling elements with the same space in the camp, resulting in a load capacity increase of the camp. The costs for production and assembly are to be reduced compared to the costs for solid brass cages. The bearing must be easy to assemble and disassemble, as well be easy to maintain.

A Role retention is to be realized as a subtask of the invention being, with a simple insertability the rolling elements in the cage should be given. Of course must have high reliability and bearing life guaranteed become.

The Task is achieved by a rolling bearing cage with the features of claim 1 solved.

The Advantages of the invention are to be seen in particular in that the increase the load rating of the rolling bearing the advantages of the conventional Machined brass cage not lost, such as safe separation, smooth driving and the safe leadership the rolling elements.

According to the invention as Cage material sheet steel used. An inventive filigree Rolling bearing cage is Cut out of a profiled sheet and then by means of bending welding put into the right shape. Since the principal production of sheet metal cages The person skilled in the art can here on a detailed description the manufacturing steps are omitted.

The Sheet metal profile can be designed in M, V, W or A profile, as with the metal cages for smaller ones roller bearing be used.

The Invention will be described below with reference to a V-profile, the Application of the invention prepares for the other known sheet metal cage profiles the expert no difficulties and is of course in the Frame of the invention.

Also can in the rolling bearing cage according to the invention all leadership styles be implemented, for example, externally guided, guided inside or also guided by rolling bodies.

Focus comes the rolling bearing cage according to the invention for bearing sizes with a shaft diameter between 150 and 260 mm for use.

Of the Inventive rolling bearing cage comprises two parallel outer rings, whose axis is coaxial with the bearing axis. Run between the outer rings in a known manner webs, which together with sections of the outer rings Forming rolling-element pockets. The webs each have two outer and an inner axially parallel web portion through which a latching the rolling elements and the leadership implemented the rolling bearing cage become. Sloping Sections connect the web parts together.

A increased Stiffness of the rolling bearing cage can by broadening the inclined sections and / or the outer and / or the inner axially parallel web portion or web portions to the side edge be achieved.

The outer web parts are outside of the roller pitch circle (center of gravity connection of the rolling elements in Bearing), whereas the inner web parts within the roller pitch circle lie.

Even though the outer rings of the cage clearly outside of the roller pitch circle is, by the web construction a Partial leadership achieved, which advantageously causes significantly reduced frictional forces.

According to the invention the neighboring points of contact between the rolling bearing cage and the rolling elements within a bridge relatively far apart.

The provided on the cage according to the invention Short scraping edges (in comparison with solid cages) ensure a good lubricating film the rolling elements, continue is through the cage design more space for Lubricant available, as with the brass solid cages.

In a preferred embodiment (V-profile) are at the inner web part, which lies within the roller pitch circle, Snap edges provided, which a self-holding and mounting aid realize for the rolling elements.

The Snap edges can in the radial direction, a chamfer have, which facilitates the mounting of the rolling elements. The bevels of two opposed Snap edges in the unbent state of the steel sheet can thereby a radially inwardly opened Have angle δ, which of rolling element diameter and / or number of rolling elements dependent can be. In particular, the angle δ in the range between 20 ° and 50 °, preferably of 24 °, chosen become.

retaining lugs at the outer web parts take care of the leadership of the cage at the rolling elements and for the outside mount the rolling elements. By the Cage design according to the invention an optimal roll sag is achieved.

The retaining lugs can also have a bevel in the radial direction. The chamfers of two opposing retaining lugs can have in the unbent state of the steel sheet a radially inwardly open angle γ, which may be dependent on Wälzkörperdurchmesser and / or Wälzkörperanzahl. In particular, the angle γ in the range between 30 ° and 80 °, preferably 54 °, are selected.

The guide of the rolling bearing cage the rolling elements is particularly stable, as these exclusively by the retaining lugs is realized. By the big one Distance of the retaining lugs to the center plane of the bearing or the cage is the cabinets and tilting of the rolling elements a minimum reduced.

According to the invention of Rolling bearing cage filigree accomplished Be by a relationship from sheet thickness to rolling element diameter is selected to be less than 0.1, preferably less than 0.08. This relationship can even with increasing stock sizes to be downsized.

A preferred embodiment The invention will be explained in more detail with reference to FIGS. It demonstrate:

1 : a filigree rolling bearing cage in a three-dimensional view;

2 : the rolling bearing cage after 1 in a cross-sectional view;

3 : A sectional view of a rolling body pocket according to section line AA in 2 ;

4 : a detail of detail B off 3 ;

5 a punched-out rolling-element pocket before bending the rolling bearing cage;

6 a sectional view of a stamped Wälzkörpertasche before the bending welding of the rolling bearing cage;

7 : a filigree rolling bearing cage in a two-dimensional view;

8th : a rolling element pocket according to section line CC in 7 ,

In 1 is an inventive filigree rolling bearing cage 01 shown in three-dimensional view. Two parallel outer rings 02 are by footbridges 03 connected with each other. The axes of rotation of the outer rings 02 are coaxial with a roller bearing axis 04 , The bridges 03 make up with the outer rings 02 so-called Wälzkörpertaschen 06 , In the described embodiment, the rolling bearing cage comprises 01 fifteen rolling-body pockets 06 ,

2 shows the rolling bearing cage 01 in a cross-sectional view. The rolling bearing cage 01 has a so-called V-profile, which is characterized by the substantially V-shaped course of the between outer rings 02 extending webs 03 is determined.

Starting from the outer rings 02 each extend to form a ridge 03 in a direction parallel to the rolling bearing axis 04 two outer web parts 07 and an inner bridge part 08 , The web parts 07 . 08 are by two sloping sections 09 connected with each other.

At the inner web parts 08 are snap edges 11 provided, with which the self-holding of the rolling elements is realized. When mounting the rolling bearing, the rolling elements are inserted from the inside into the cage until the snap edge 11 has overcome the full circle of the rolling body.

The outer web parts 07 have retaining lugs 12 on, which hold the rolling elements to the outside. After snapping in the Wälzkörpertasche 06 the rolling element is thus between the snap edge 11 and the retaining lugs 12 held so that he can not fall out of the bag.

In the described preferred embodiment, the rolling bearing cage has 01 a diameter D having a ratio of about 3/1 to a cage width b. The ratio of the diameter D to the thickness d of the steel sheet is 85 in the described embodiment.

3 shows a sectional view of a rolling body pocket 06 in accordance with the section line or center plane of the bearing or of the cage AA in FIG 2 , A rolling element 13 is located in the Wälzkörpertasche 06 , The dash-dotted lines are the maximum roller slack positions of the rolling element 13 shown. 13 ' represents the position of the outer holder. In this case, the rolling element 13 through the retaining lugs 12 kept in a cage. Preferably, the retaining lugs have a chamfer 14 on. These are dimensioned such that they in the bent state of the rolling bearing cage 01 an angle α of about 30 ° to each other, wherein the opening of the angle α in the direction of the rolling bearing axis 04 has.

The sloping sections 09 pointing in the bent state of the rolling bearing cage 01 preferably at an angle β of about 24 ° with outwardly facing angular opening.

The rolling bearing position of the inner holder is with 13 '' shown. The inner web parts 08 keep the rolling elements in the inner position. Due to the minimal roll sag achieved, the assembly operations are simplified.

Out 3 is also the size ratio of rolling element diameter to the width of the webs 03 he visibly, which according to the invention should be less than 0.1, in particular less than 0.08. Also visible is the already mentioned large distance of the retaining lugs 12 to the middle level AA.

In 4 is the detail B off 3 shown enlarged. It shows a sectional view of the inner web part 08 with the snap edge 11 , Due to the design, the mounting of the rolling elements is much easier. The introduction of the rolling elements takes place from below, as a result of the resilient properties of the cage material, the web parts are pushed away from the rolling element until the snap edges engage. The snap edges 11 preferably have a chamfer 16 on.

5 shows a Wälzkörpertasche 06 before bending the rolling bearing cage. The rolling-body pockets are preferably punched out of a profiled steel sheet or strip. Subsequently, the bending and joining takes place. Usually, the assembly of the rolling bearing cages is done in one step in a bending machine.

The bridges 07 have approximately the same width as the outer rings 02 , This ratio ensures optimum strength of the cage. Cage loads are mainly absorbed or reduced by the elasticity of the roller bearing cage.

The edge corner radii of the web parts 07 . 08 are optimized according to the stresses occurring in the cage. Their determination is not difficult for the skilled person.

In 6 is a rolling-element bag 06 before bending the profiled steel sheet to the rolling bearing cage 01 shown. This figure shows the dimensions which are matched to the respective function of the bearing.

In particular, these are an angle γ, which is located between the bevels 14 the retaining lugs 12 extends. In the described preferred embodiment, γ is about 54 ° with the opening facing radially inward.

The bevels 15 two opposite snap edges 11 have in this preferred embodiment at an angle δ of about 24 ° with radially also inwardly facing opening.

In 7 is another inventive filigree rolling bearing cage 01 shown in two-dimensional view. Two parallel outer rings 02 are by footbridges 03 connected with each other. The axes of rotation of the outer rings 02 are coaxial with a roller bearing axis 04 , The bridges 03 make up with the outer rings 02 so-called Wälzkörpertaschen 06 ,

8th shows a sectional view of a rolling body pocket 06 according to the section line CC in 7 ,

Starting from the outer rings 02 each extend to form a ridge 03 in a direction parallel to the rolling bearing axis 04 two outer web parts 07 and an inner bridge part 08 , The web parts 07 . 08 are by two sloping sections 09 connected with each other. The sloping sections 09 run in this case radially outward.

To increase the rigidity of the rolling bearing cage 01 is a broadening of the outer axially parallel web parts 07 and the inner axially parallel web portion 08 realized to the side edge.

01

Rolling bearing cage

02

outer ring

03

web

04

Rolling axis

05

-

06

rolling body

07

Bridge part, outside

08

Web part, inner

09

section

10

-

11

snap edge

12

retaining nose

13

rolling elements

14

Bevel on retaining nose

15

-

16

Bevel on snap edge

A-A

midplane of the bearing or cage, section line

C-C

intersection

Claims (14)

Rolling bearing cage ( 01 ) for roller bearings of a profiled sheet steel with a plurality of rolling bearing pockets ( 06 ) for receiving rolling elements ( 13 ), which by two parallel outer rings ( 02 ) and between the outer rings ( 02 ) running webs ( 03 ) are formed, wherein the webs ( 03 ) each have two outer axially parallel web parts ( 07 ) and an inner axially parallel web part ( 08 ), which are defined by oblique sections ( 09 ), characterized in that the steel sheet has a thickness which is smaller than 0.1 times the rolling element diameter. Rolling bearing cage ( 01 ) according to claim 1, characterized in that it is suitable for rolling bearings with a Shaft diameter greater than 100 mm is designed. Rolling bearing cage ( 01 ) according to claim 1 or 2, characterized in that it has an A, W, M or V profile. Rolling bearing cage ( 01 ) according to one of claims 1 to 3, characterized in that the outer web parts ( 07 ) directly to the outer rings ( 02 ) connect. Rolling bearing cage according to one of claims 1 to 4, characterized in that the inner web parts ( 08 ) Snap edges ( 11 ) having an inner support of the rolling elements ( 13 ) realize. Rolling bearing cage according to one of claims 1 to 5, characterized in that the outer web parts ( 07 ) Retaining lugs ( 12 ) having an outer support of the rolling elements ( 13 ) realize. Rolling bearing cage ( 01 ) according to one of claims 1 to 6, characterized in that the width of the outer rings ( 02 ) approximately equal to the width of the inner web parts ( 08 ). Rolling bearing cage ( 01 ) according to one of claims 1 to 7, characterized in that the ratio of the diameter D to the width b of the rolling bearing cage ( 01 ) is greater than 2, preferably equal to 3. Rolling bearing cage ( 01 ) according to one of claims 1 to 8, characterized in that the diameter D of the roller bearing cage ( 01 ) to the thickness d of the steel sheet has a ratio greater than 80, preferably of 85. Rolling bearing cage ( 01 ) according to one of claims 5 to 9, characterized in that the snap edges ( 11 ) in the radial direction a bevel ( 16 ), which facilitates the assembly of the rolling elements. Rolling bearing cage ( 01 ) according to claim 10, characterized in that the bevels ( 16 ) of two opposite snap edges ( 11 ) in the unbent state of the steel sheet have a radially inwardly opened angle δ in the range between 20 ° and 50 °, preferably of 24 °. Rolling bearing cage according to one of claims 6 to 11, characterized in that the retaining lugs ( 12 ) in the radial direction a bevel ( 14 ) exhibit. Rolling bearing cage according to claim 12, characterized in that the bevels ( 14 ) of two opposing retaining lugs ( 12 ) in the unbent state of the steel sheet have a radially inwardly opened angle γ in the range between 30 ° and 80 °, preferably of 54 °. Rolling bearing cage ( 01 ) according to one of the preceding claims, characterized in that the oblique sections ( 09 ) and / or the outer axially parallel web parts ( 07 ) and / or the inner axially parallel web part ( 08 ) are widened towards the edge of the page.