DE102012207927B4 - Rolling bearing assembly, in particular for a radial rolling bearing - Google Patents

Abstract

Rolling bearing arrangement, in particular for a radial roller bearing (1), essentially consisting of a bearing outer ring (4) insertable into a bearing receptacle (2) of a component (3) and of a rolling element ring (5) arranged in this bearing outer ring (4), which is guided by a bearing cage (6) and a plurality in this circumferentially uniformly spaced rolling elements (7) is formed on the inner circumferential surface (8) of the bearing outer ring (4) and on the outer circumferential surface (9) of an axle (10), a shaft or a Rolling off separate bearing inner ring, wherein the radial rolling bearing (1) by means of a press fit between the outer circumferential surface (11) of its bearing outer ring (4) and the inner circumferential surface (12) of the bearing receptacle (2) of the component (3) in the bearing receptacle (2) is fixed and with additional securing means (13) against rotation and axial displacement of the bearing outer ring (4) in the bearing receptacle (2) is formed, wherein the securing means (13) by an at least on the outer circumferential surface (11) of the bearing outer ring (4) applied soft metallic coating (14) formed by flowing into the surface roughness (15) of the inner circumferential surface (12) of the bearing receptacle (2) during the pressing of the radial roller bearing (1) fixed in the bearing receptacle (2) the outer bearing ring (4) of the radial rolling bearing (1) by a mixed form of force, form and material against rotation and axial displacement in the bearing receptacle (2), wherein the coating (14) of the Bearing outer ring (4) is formed by a galvanically applied corrosion protection layer based on an iron-zinc alloy with an iron content of 0.3% to 1%, without another layer for their passivation, and wherein, having the bearing receptacle (2) Component (3) is a planetary gear of a planetary gear (16) in a car starter.

Description

Field of the invention

The invention relates to a rolling bearing assembly, in particular for a radial rolling bearing, consisting essentially of a usable in a bearing receptacle of a component bearing outer ring and a arranged in this bearing outer ring Wälzkörperkranz, which is formed by a bearing cage and a plurality in this circumferentially guided at uniform intervals rolling elements , The rolling elements roll on the inner lateral surface of the bearing outer ring and on the outer lateral surface of an axle, a shaft or a separate bearing inner ring, wherein the radial rolling bearing is fixed by means of a press fit between the outer circumferential surface of its outer bearing ring and the inner lateral surface of the bearing seat of the component in the bearing seat and with additional securing means formed against rotation and axial displacement of the bearing outer ring in the bearing receptacle.

Background of the invention

In rolling bearing technology, it is well known that needle sleeves are the type of needle bearings that have the smallest radial height and allow particularly space-saving and easy to mount bearings with high radial load capacity. Such needle sleeves are known for example from the catalog "Rolling Bearings" of the Applicant, October 2008 edition, on pages 681 to 697 and are used in many applications in motor vehicles and in the storage of planet gears of a planetary gear in a car starter. The needle sleeves used in this case consist of an insertable into a hole in the planetary outer ring and a plurality within the outer ring in a needle cage in the circumferential direction out at uniform intervals and rolling on the inner circumferential surface of the outer ring and on the outer circumferential surface of the Planetenradachse rolling bearing needles, and are by means of a press fit attached between the outer circumferential surface of the outer ring and the inner circumferential surface of the bore in the planetary gear in the bore.

The DE 31 31 149 A1 discloses a starting device for an internal combustion engine with a planet gear, which is mounted by means of a needle bearing on a shaft.

The DE 197 26 726 A1 describes a free-launching starter for cranking internal combustion engines in motor vehicles.

Due to the ever increasing loads and the ever-smaller designs of car starters, however, it comes especially in the field of storage of the planetary gears of the planetary gear to micro-movements that cause the needle sleeve begins to wander within its bore in the planetary gear in the circumferential direction. In the course of these micromovements, as a result of a resulting screwing effect, the needle sleeve then moves axially out of the bore in the planetary gear, so that destruction of the planetary gear can occur due to the steadily decreasing bearing support of the planetary gear.

To avoid these micro-movements, it was therefore first attempted to increase the coverage of the interference fit between the outer ring of the needle hub and the bore in the planet gear, thereby increasing the frictional resistance between these components. However, it has been shown that with such a measure within the permissible deformation limits of needle sleeve and planetary gear can not be achieved to avoid micro-movements sufficient frictional resistance.

In addition, from the prior art, a variety of other solutions known to fix a radial rolling bearing against rotation and / or axial displacement in its bearing receptacle.

For example, the DE 15 25 296 A1 a bearing of a shaft of a steering gear via a radial needle bearing relative to a housing in which the radial needle bearing has a made of a sheet metal bearing sleeve with radially inwardly facing ribs, roll on the inner lateral surface of the needles. This bearing sleeve is formed on an inboard side with a flange-like system in the form of a radially outwardly projecting U-shaped fold, which comes in the installed state of the radial needle bearing to rest against the housing wall and thereby a positive locking against axial displacement of the radial needle bearing against the housing wall in a Direction forms. The axial securing in the other direction takes place through the use of an end plate, which has an annular recess and is connected to the housing wall, so that the flange-like contact between the housing wall and the end plate is fixed against axial displacement. Furthermore, from the DE 26 11 218 A1 a positive and non-positive fixation of a trained as a ball bearing radial roller bearing in the bearing seat in a housing wall, in which the outer ring of the ball bearing is formed at the edge of its outer circumferential surface with a circumferential groove. After insertion of the ball bearing in the bearing seat in the housing wall, the softer than the material of the outer ring formed material of the housing wall in the immediate vicinity of the bearing seat sections deformed by means of a press ram so that the material of the housing wall is displaced in the radial direction in the groove of the outer ring and thus fixes the ball bearing against rotation and axial displacement in the bearing seat.

Furthermore, by the DE 39 31 447 A1 Among other things, the attachment of a designed as a cylindrical roller bearing radial roller bearing by means of press fit in a bearing seat of a softer housing disclosed in which the axial position assurance of the outer ring of the cylindrical roller bearing is effected by at least one circumferential groove in the contact area between the outer ring and housing. The groove in this case has a sharp-edged transition to the cylindrical outer surface of the outer ring, can be scraped off by the material of the softer surface of the bearing seat and can accumulate in the grooves. As a result of the selected interference fit between the outer ring and the housing thus swells in the bearing mounting material of the housing in the groove of the outer ring, which comes to a thickening of the housing and to an axial positional securing of the outer ring by positive engagement.

In addition, through the DE 101 53 432 C1 a further attachment of a trained as a ball bearing radial roller bearing in a bore of a housing known, the outer ring has a radially extending flange at the edge. This flange has a circumferentially circumferential axial wedge extension, which forms a stamp member which comes into contact with a radial housing wall during assembly of the ball bearing in the bore of the housing. Upon further pressing of the ball bearing in the housing, the stamp member causes a plastic deformation of the material of the radial housing wall radially in a arranged adjacent to the wedge extension circumferential recess in the outer ring, so that it is positively secured against axial displacement. An additional connection between the outer ring and the housing also takes place in that immediately adjacent to the recess in the outer ring, the lateral surface of the outer ring is provided with a knurling, which forms in the bore of the housing, so that by the resulting positive locking and a rotation of the outer ring is excluded relative to the housing after assembly.

Another safeguard against rotation of a designed as a needle bearing radial roller bearing in the bearing seat is from the DE 101 23 965 A1 known. The needle bearing disclosed therein consists in a known manner of a thin-walled outer ring and a needle ring inserted into the outer ring and is characterized in that the outer ring on one axial side has a radially inboard board, while the other axial side is designed without a bord and the periphery has two radially outwardly bent tabs. These lobes are introduced during assembly of the needle bearing in corresponding grooves in the bearing seat and thus form an anti-rotation. However, since there is a risk of the needle ring wandering out of the outer ring due to the one-sided design of the needle bearing without the board, the missing board is formed by an additional thrust washer, which is fastened to the lobe of the outer ring.

In the DE 10 2007 022 316 A1 Furthermore, a solution for securing a needle sleeve against twisting and axial displacement in the bearing seat of a housing is disclosed, which consists in disengaging two oppositely arranged retaining lugs from the outer circumferential surface of the outer ring outside the raceway region of the bearing needles and making them radially outward so that they project beyond the outer circumferential surface of the outer ring. These retaining lugs are resilient and hooked after mounting the needle sleeve in the softer than the needle sleeve formed material of the housing such that the needle sleeve can not rotate in the bearing seat by the resulting form-fitting or move axially.

One of the above solution very similar backup of a needle sleeve against rotation and axial displacement in the bearing seat of a housing is also from the DE 10 2007 046 527 A1 known. In this solution, instead of the retaining lugs in the outer circumferential surface of the outer ring at the transition between one of the radial edges of the needle sleeve to the outer circumferential surface of a projection formed without cutting, which also projects beyond the outer circumferential surface of the needle sleeve. When pressing the bearing sleeve into the bearing seat of the housing, this projection also produces by plastic deformation a recess in the softer than the needle sleeve formed material of the housing in which the needle sleeve is positionally secured against rotation and rotation.

Finally, in the DE 10 2007 043 627 A1 nor discloses a mounting of a radial roller bearing in a bore of a housing, in which a plurality of mutually crossing grooves are arranged with an inclination relative to the longitudinal center axis of the bearing in the outer ring of the radial roller bearing. In addition, a cylindrical ring of a resin is pushed onto the outer ring formed in this way, which is heated in the bearing seat after insertion of the radial roller bearing. By heating the cylindrical ring, the resin then flows into the grooves in the outer circumferential surface of the outer ring and simultaneously connects to the bearing seat, so that the radial roller bearing is fixed against rotation and axial displacement.

The DE 10 2004 043 125 A1 describes a throttle device in which a permanent stabilization of the bearing support is generated by a clamping ring.

However, all the above known solutions for securing a radial rolling bearing against rotation and / or axial displacement in the bearing seat have the disadvantage that for their implementation in any case additional mechanical means on the bearing seat and / or the radial rolling bearing itself are necessary, which require an increased production costs and thereby increase the manufacturing cost of the rolling bearing assembly. In addition, a plurality of said solutions require a bearing seat in a softer than the material of the outer ring of the radial roller bearing formed housing, so that these solutions are not suitable for rolling bearing assemblies in which the material of the outer ring at least approximately the same hardness as the material of the component having the bearing seat.

The WO 2009/103378 A1 describes a control device which consists essentially of a throttle body with a gas passage and a throttle valve. The existing throttle valve bearings in the form of needle bearings each have a made of high-alloy corrosion-resistant steel sheet existing needle sleeves, which are produced without cutting by deep drawing.

The DE 10 2007 013 937 A1 discloses a throttle body and a method of manufacturing the same. The throttle body has two storage devices wherein at least one of which has an outer ring which is formed of stainless steel material or hardened or with a corrosion protection layer such as Corrotect ^®, is coated.

The DE 102 58 241 A1 describes a radial bearing, which is arranged between two with a differential speed against each other rotating gear parts. The radial bearing has an inner and / or outer sleeve between the rolling elements and the transmission parts. The inner and / or outer sleeve is provided for better adhesion of nested or superimposed components with a galvanically applied layer having ZnNi or ZnFe, such as Corrotect ^® .

The INA / FAG publication "special coating Corrotect ^®", catalog TPI 67D.D, February 2008, describes the composition of a Corrotect ^® - coating, in addition to a zinc alloy layer, a thick-film or nanoparticle-based thick film passivation is present.

Object of the invention

Based on the stated disadvantages of the known prior art, the invention is therefore based on the object to design a rolling bearing assembly, in particular for a radial roller bearing, in which the securing means of the radial roller bearing against rotation and / or axial displacement in the bearing seat inexpensive to produce and also for Rolling bearing arrangements is suitable, in which the material of the outer ring has at least approximately the same hardness as the material of the component with the bearing seat.

Description of the invention

According to the invention this object is achieved in a rolling bearing assembly such that the securing means is formed by an applied at least on the outer circumferential surface of the bearing outer ring soft metallic coating, which by flowing into the surface roughness of the inner surface of the bearing housing when pressing the Radialwälzlagers in the bearing support the bearing outer ring of the radial roller bearing fixed a mixed form of force, form and material against rotation and axial displacement in the bearing holder.

Thereafter, it is provided in the inventively embodied rolling bearing arrangement that the coating of the bearing outer ring is formed by a galvanically applied corrosion protection layer based on a zinc-iron alloy. The zinc-iron used is a zinc alloy with an iron content of 0.3% to 1%, which is characterized by high resistance to environmental influences, in the inventive application, however, has proven by their excellent flow properties at the same time as particularly suitable.

In specific embodiments, the coating as a thin film coating of the outer bearing ring, similar to a Corrotect ^® coating, wherein the passivating layer is omitted otherwise conventional, are formed. The silver iridescent passivation usually chemically produced is used when using Corrotect ^® as a corrosion protection layer to protect the zinc-iron alloy from premature dissolution, but would in the inventive application, adversely affect the flow properties of the zinc-iron alloy and is therefore omitted.

The bearing receiving component according to the invention in the form of a planetary gear his planetary gear in a car starter trained.

Preferred embodiments and further developments of the rolling bearing arrangement designed according to the invention are described in the subclaims.

A further preferred feature of the rolling bearing arrangement designed according to the invention is that the coating is applied to the entire bearing outer ring and has a layer thickness of at most 5 μm on its outer circumferential surface. The coating is applied in manufacturing technology simplest and most cost-effective manner in a galvanic immersion bath on the bearing outer ring, in which also its trained with the career of the rolling elements inner surface is coated to a small extent. However, the low coating of the raceway for the rolling elements does not adversely affect the rolling properties of the track, since the coating is rolled after a few revolutions of the rolling elements of these in the base material of the bearing outer ring or removed again from the inner surface. The layer thickness of the coating on the outer circumferential surface of the bearing outer ring is of course dependent on the size of the surface roughness of the inner circumferential surface of the bearing receptacle, so that in certain applications, layer thicknesses over 5 microns are conceivable. However, a layer thickness of 5 microns is an upper limit for the attachment of radial rolling bearings in stock images with the usual surface roughness, since it was found that higher layer thicknesses cause the interference fit between the bearing mount and the bearing outer ring is supported only on the coating and that the low strength of the coating of the press fit then tends to tear within the coating, as a result of which the axial outward migration of the radial rolling bearing from the bearing seat is even faster.

In a further preferred embodiment, the inventively embodied rolling bearing assembly is also characterized by the fact that the average coverage of the interference fit between the coated bearing outer ring and the bearing seat is about 40 microns. Also, this value has proven in the most common fortifications of radial bearings in bearing mounts as optimum for a maximum achievable holding force between the bearing outer ring and the bearing receptacle, since it was found that at a much smaller overlap of the press fit, the holding force of the desired "cold welding" between two components is not sufficient and at a much larger coverage of the press fit it comes at least to a partial scraping of the coating through which the remaining layer thickness is insufficient to flow into the surface roughness of the bearing support and to be able to produce the "cold welding" between the components.

Finally, it is regarded as an advantageous application of the inventively embodied rolling bearing arrangement, when the radial rolling bearing is preferably designed as a needle sleeve with non-cutting shaped thin-walled bearing outer ring.

It is particularly preferred if the rolling elements roll on the inner circumferential surface of the bearing outer ring and on the outer circumferential surface of an axle or a shaft.

Furthermore, it has proven useful if a material of the outer ring has at least approximately the same hardness as a material of the component with the bearing seat.

However, the invention should not be limited to the stated application, but is basically applicable to all press band connections, in which the holding force of the connecting components to be increased.

In summary, the inventively designed roller bearing thus has the advantage over the rolling bearing arrangements known from the prior art that for the securing means of the radial roller bearing against rotation and / or axial displacement in the bearing seat no additional, increasing the manufacturing cost mechanical means on the bearing seat and / or on Radialwälzlager Even more are necessary, but that the securing means is designed as a cost-producible soft metallic coating that fixes the bearing outer ring in the bearing seat by "cold welding" and which is also suitable for rolling bearing assemblies in which the material of the outer ring at least approximately the same hardness as the material having the component with the bearing seat.

Brief description of the drawings

A preferred embodiment of the inventively embodied rolling bearing assembly will be explained in more detail with reference to the accompanying drawings. Showing:

1 an enlarged detail of a plan view of a planetary gear with a bearing on a inventively designed needle sleeve planet gear;

2 a further enlarged section of the cross section AA according to 1 by the mounted on the inventively designed needle sleeve planetary gear;

3 a photomicrograph of a section through the connection of the inventively designed needle sleeve with the bearing receptacle in the planetary gear in a flat region;

4 a further light micrograph of a section through the connection of the inventively designed needle sleeve with the bearing receptacle in the planetary gear in the region of a pore.

Detailed description of the drawings

Out 1 is clearly a section of a plan view of a planetary gear 16 in which the planetary gear shown 3 on a trained as a needle sleeve radial roller bearing 1 is stored. In synopsis with 2 is furthermore to see that the bearing assembly of the planetary gear 3 essentially from one to a warehouse 2 of the planet wheel 3 usable, chipless shaped, thin-walled bearing outer ring 4 and from one in this bearing outer ring 4 used Wälzkörperkranz 5 consisting of a trained as a needle cage bearing cage 6 and a plurality of rolling elements guided in the circumferential direction at regular intervals and formed as bearing needles 7 is formed, which on the inner circumferential surface 8th of the bearing outer ring 4 and on the outer circumferential surface 9 one the planetary gear 3 supporting axle 10 roll. The trained as a needle sleeve radial roller bearing 1 is by means of a press fit between the outer circumferential surface 11 his bearing outer ring 4 and the inner circumferential surface 12 the camp admission 2 of the planet wheel 3 in the warehouse 2 attached and, as will be explained in more detail below, with additional securing means 13 against rotation and axial displacement of the bearing outer ring 4 in the warehouse 2 educated.

The in the 3 and 4 pictured light micrographs then clearly show that these securing agents 13 according to the invention by a on the outer circumferential surface 11 of the bearing outer ring 4 applied soft metallic coating 14 is formed by the inflow into the surface roughness 15 the inner circumferential surface 12 the camp admission 2 when pressing in the radial roller bearing 1 in the warehouse 2 the bearing outer ring 4 of the radial rolling bearing 1 by a mixed form of force, form and material against rotation and axial displacement in the bearing receptacle 2 fixed.

The coating 14 of the bearing outer ring 4 is formed by a galvanically applied corrosion protection layer based on an iron-zinc alloy g with an iron content of 0.3% to 1% (similar to a Corrotect ^® coating without passivation), which is applied to the entire bearing outer ring 4 is applied and on the inner circumferential surface 8th from the rolling elements 7 is removed again.

A maximum holding force of the generated connection between the bearing outer ring 4 and the camp admission 2 is achieved when the coating 14 as in the 3 and 4 shown on the outer surface 11 of the bearing outer ring 4 has a layer thickness of 5 microns maximum and the average coverage of the interference fit between the coated bearing outer ring 4 and the camp admission 2 is about 40 microns.

LIST OF REFERENCE NUMBERS

1

radial bearings

2

bearing seat

3

Component / planet

4

Bearing outer ring

5

Wälzkörperkranz

6

bearing cage

7

rolling elements

8th

Inner lateral surface of 4

9

Outer jacket surface of 10

10

Axis of 3

11

Outer jacket surface of 4

12

Inner lateral surface of 2

13

securing means

14

coating

15

Surface roughness of 12

16

planetary gear

Claims (6)

Rolling bearing arrangement, in particular for a radial rolling bearing ( 1 ), essentially consisting of one in a bearing receptacle ( 2 ) of a component ( 3 ) usable bearing outer ring ( 4 ) as well as from one in this bearing outer ring ( 4 ) arranged Wälzkörperkranz ( 5 ) through a cage ( 6 ) and a plurality in this circumferentially evenly spaced rolling elements ( 7 ) is formed on the inner circumferential surface ( 8th ) of the bearing outer ring ( 4 ) and on the outer circumferential surface ( 9 ) of an axis ( 10 ), a shaft or a separate bearing inner race, the radial rolling bearing ( 1 ) by means of a press fit between the outer circumferential surface ( 11 ) of its bearing outer ring ( 4 ) and the inner surface ( 12 ) of the camp admission ( 2 ) of the component ( 3 ) in the warehouse ( 2 ) and with additional securing means ( 13 ) against rotation and axial displacement of the bearing outer ring ( 4 ) in the warehouse ( 2 ), wherein the securing means ( 13 ) by at least on the outer circumferential surface ( 11 ) of Bearing outer ring ( 4 ) applied soft metallic coating ( 14 ) formed by flowing into the surface roughness ( 15 ) of the inner circumferential surface ( 12 ) of the camp admission ( 2 ) when pressing in the radial rolling bearing ( 1 ) in the warehouse ( 2 ) the bearing outer ring ( 4 ) of the radial rolling bearing ( 1 ) by a mixed form of force, form and material against rotation and axial displacement in the bearing receptacle ( 2 ), wherein the coating ( 14 ) of the bearing outer ring ( 4 ) is formed by a galvanically applied corrosion protection layer on the basis of an iron-zinc alloy with an iron content of 0.3% to 1%, without a further layer for their passivation, and wherein, the bearing receptacle ( 2 ) component ( 3 ) a planetary gear of a planetary gear ( 16 ) is in a car starter. Rolling arrangement according to claim 1, wherein the coating ( 14 ) on the entire bearing outer ring ( 4 ) is applied and on the outer circumferential surface ( 11 ) has a layer thickness of at most 5 microns. Rolling arrangement according to claim 2, wherein the average overlap of the interference fit between the coated bearing outer ring ( 4 ) and the bearing receiver ( 2 ) is about 40 microns. Rolling bearing assembly according to claim 3, wherein the radial rolling bearing ( 1 ) preferably as a needle sleeve with non-cutting, thin-walled bearing outer ring ( 4 ) is trained. Rolling bearing arrangement according to one of claims 1 to 4, wherein a material of the bearing outer ring ( 4 ) has at least approximately the same hardness as a material of the component ( 3 ) in the form of the planetary gear. Rolling bearing arrangement according to one of claims 1 to 5, wherein the rolling elements ( 7 ) on the inner circumferential surface ( 8th ) of the bearing outer ring ( 4 ) and on the outer circumferential surface ( 9 ) of an axis ( 10 ) or a shaft.

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