DE102024104016B4 - rolling bearing arrangement - Google Patents

Abstract

Rolling bearing arrangement (1) which is formed from at least one set of cylindrical rollers (5), a static inner bearing ring (7) and a rotatable outer bearing ring (2) and a bypass device (20) and also comprises a first machine element (30) and a second machine element (31), wherein:
- the cylindrical roller set (5) comprises a plurality of cylindrical rollers (8), and
- the cylindrical rollers (8) of the cylindrical roller set (5) are arranged radially between the inner bearing ring (7) and the outer bearing ring (2), and are directed radially transversely to the axis of rotation (16),
- the inner bearing ring (7) and the outer bearing ring (2) are arranged concentrically on an axially aligned axis of rotation (16) of the rolling bearing arrangement (1),
- at least one electrical connection is formed between the first machine element (30) and the second machine element (31) via the bypass device (20),
- the bypass device (20) comprises a holder (21) and at least one electrically conductive bypass conductor (23), wherein the holder (21) and bypass conductor (23) are electrically connected to each other,
- the holder (21) is axially secured by means of a positive fit between the inner bearing ring (2) and a shoulder in the first machine element (30) and holds the bypass conductor (23),
- wherein the inner bearing ring (2) is attached to the first machine element (30),
- wherein a bearing space (19) is formed between the inner bearing ring (7) and the outer bearing ring (2),
- wherein a contact area (14) is formed on the outer bearing ring (2) radially inwards in the direction of the bearing space (19), in which the electrical contact between bypass conductor (23) and outer bearing ring (2) is formed,
- and wherein the bypass conductor (23) radially contacts the contact area (14)
- wherein the contact area (14) comprises a layer system (3) electroplated on the second machine element (31), wherein the layer system (3) optionally comprises a first layer (3a) arranged on the second machine element (5) and at least one second layer (3b) arranged on the second machine element (5) or, if present, on the first layer (3a), wherein the optional first layer (3a) is formed of copper or nickel and the at least one second layer (3b) is formed of an alloy comprising at least two of the elements tin, copper, nickel, silver, zinc, bismuth, antimony, cobalt, manganese, tungsten, wherein non-metallic particles comprising electrically conductive particles are incorporated in the alloy and wherein the alloy of the second layer is formed of a tin-nickel alloy with a nickel content in the range of 20 to 40 wt.%.

Description

Field of invention

The invention relates to a rolling bearing arrangement which is formed from at least one first and one second machine element, a set of cylindrical rollers, two bearing rings and a bypass device.

Background of the invention

Rotor shafts in electric machines are usually supported by rolling bearings. Unwanted voltage potentials often arise between the rotor shafts and the housings of electric motors and generators. Without countermeasures, these voltage potentials discharge through the rolling bearings. The current flowing through the affected rolling bearing can generate sparks in the rolling contact between the rolling elements and the raceways. The rolling raceways are damaged by melt pitting or erosion pitting.

Measures are already known to prevent the build-up or dissipation of voltage potentials via the rolling bearings. For example, bypass devices are used, which divert discharges around the rolling bearings of the electric motor via so-called shaft grounding rings. DE 10 2016 010 926 A1 A bypass device consisting of a shaft grounding ring is disclosed. This shaft grounding ring has a disc-shaped, electrically conductive bypass conductor, which is clamped between two conductive angle brackets on the housing side and bears against a shaft with elastic preload on the inside. The angle brackets forming the holder of the bypass conductor are inserted into a housing at any suitable location. The bypass conductor is made of a conductive material that has a lower resistance to current flow than, for example, steel. The advantage of such a bypass device is that the shaft grounding ring is simple and inexpensive to manufacture. Further bypass devices for rolling bearings are described in the publications. DE 10 2022 113 004 A1 , the DE 10 2019 133 884 A1 as well as the FR 3 121 802 A1 addressed.

In the automotive sector, bypass conductors are often integrated into sealing devices by experts. An example of a pre-seal designed as a bypass conductor is shown with... DE 10 2014 010 269 B4 The following is revealed: The upstream seal is connected in series upstream of a main seal and simultaneously acts as a bypass conductor, establishing an electrically conductive connection between two machine elements. The disc-shaped bypass conductor is designed to protect the sealing lip of the main seal from environmental contaminants and is attached to the main seal. The main seal is mounted in the housing with a holder formed from an angle bracket.

Due to their primary application in electric motors and the resulting requirements for high relative speeds, the aforementioned bypass devices proposed in the prior art are generally used with ball bearings. The bypass devices are either integrated into the bearing or make contact with the shaft at any point. Cylindrical roller bearings, by design, are better suited for higher loads and lower speeds and are typically used in industrial applications. Since the currents involved are higher, bypass devices for these applications can be positioned at any point within the system, making contact with the shaft.

Description of the invention

The object of the invention is to create an improved rolling bearing arrangement with bypass for high-speed cylindrical roller bearings.

The problem is solved according to the subject matter of claim 1. The rolling bearing arrangement comprises at least a first machine element and a second machine element, a cylindrical roller assembly, a static inner and a rotatable outer bearing ring, and a bypass device. The cylindrical roller assembly comprises a plurality of cylindrical rollers. The cylindrical rollers of the cylindrical roller assembly are arranged radially between the inner and the outer bearing ring and are oriented radially transversely to the axis of rotation. The bearing ring is arranged concentrically on an axially aligned axis of rotation of the rolling bearing arrangement. At least one electrical connection is formed between the first machine element and the second machine element via the bypass device. The bypass device comprises a holder and at least one electrically conductive bypass conductor, which are conductively connected to each other. The holder is positively engaged between the inner bearing ring and the first machine element and holds the bypass conductor. The holder is also axially engaged between the inner bearing ring and a shoulder in the first machine element, the inner bearing ring being attached to the first machine element. A bearing gap is formed between the inner bearing ring and the outer bearing ring, with the outer bearing ring extending radially inwards in the direction of the bearing gap. a contact area is formed, i.e., on the inner diameter of the outer bearing ring, where the electrical contact between the bypass conductor and the bearing ring is formed, with the bypass conductor contacting the contact area radially.

Typically, bypass devices are held on the outer bearing ring of a rolling bearing and overlap the inner bearing ring to a greater or lesser extent to ensure permanent mechanical and electrical contact. This has the advantage of allowing for generous tolerances. Surprisingly, in bearings with rotating outer rings, it has been shown that a permanent contact, even an improved form of bypass conductor, can also be established in the bearing space with the conductor mounted on the rotating inner bearing ring, provided the contact is made on the outer bearing ring, specifically on its inner diameter. This ensures reliable and permanent contact between the outer bearing ring and the bypass conductor.

A particularly secure and simple mounting of the bypass device can be achieved if the holder is attached by means of a positive fit between the inner bearing ring and the first machine element. This eliminates the need for complex mounting geometries. Furthermore, this has the advantage that only minimal axial installation space is required for the bypass device.

The contact area of the outer bearing ring, where the bypass conductor contacts the outer bearing ring, comprises an electroplated layer system, wherein the layer system optionally includes a first layer arranged on the outer bearing ring and at least one second layer arranged on the outer bearing ring or, if present, on the first layer. The optional first layer is formed of copper or nickel, and the at least one second layer is formed of an alloy comprising at least two of the elements tin, copper, nickel, silver, zinc, bismuth, antimony, cobalt, manganese, and tungsten, wherein non-metallic particles comprising electrically conductive particles are incorporated into the alloy.

Generally, bypass devices do not have a coating on the counter-running surface, i.e., the contact surface, because this is usually integrated into the existing system, for example, as the shaft of an electric motor or as the bearing ring of a rolling bearing, and is therefore difficult to coat. Surprisingly, however, it has been found that an electroplated coating system, as described above, exhibits ideal properties as a contact surface for a bypass conductor. Firstly, ideal and improved current transmission can be observed, even with the presence of lubricant layers. Secondly, such a coating system exhibits ideal properties with regard to friction and wear. The proposed rolling bearing arrangement takes this as an opportunity to equip the contact surface with the aforementioned coating system, despite the previously mentioned constraints.

The electrically conductive particles exhibit an electrical conductivity ranging from 0.25 mΩ*cm*cm to 10 mΩ*cm*cm within a temperature range of 20 to 25°C. The presence of non-metallic particles, embedded in the alloy in the second layer, improves the mechanical stability of the layer system and, depending on the particle material, further reduces the interfacial resistance, thereby increasing the current transfer capacity at the contact surface.

With regard to the electroplated coating system of the contact surface of the first machine element, the alloy consists of a tin-nickel alloy with a nickel content in the range of 20 to 40 wt.%. Such a low nickel content is highly advantageous, as second layers of such a tin-nickel alloy with electrically conductive particles dispersed therein, in particular carbon and/or graphite and/or carbon nanotubes and/or carbon fibers and/or carbon black and/or graphene and/or graphene oxide, have proven to be more stable in the long term than comparable gold layers.

It is also particularly suitable if the bypass device holder is designed in two parts, comprising a retaining disc and a clamping disc that hold the bypass conductor. In this way, even bypass conductors that are inherently unstable, i.e., lack reinforcing elements, can be securely held by the holder.

A particularly secure and simple mounting of the bypass device can be achieved if the bypass device holder engages radially in a groove-shaped undercut between the inner bearing ring and the first machine element. This makes the mounting particularly space-saving, requiring only minimal axial installation space for the bypass device to ensure ideal positioning in the seating area.

The bypass device is arranged axially on one side of the rolling elements. On this side, the outer bearing ring preferably has a greater axial extent than on the The opposite side is designed to accommodate the bypass device. If flanges are provided on the outer ring, the flange on the bypass device side can have a greater axial extent. It may be suitable to design the outer bearing ring so that it terminates with the bypass device on a plane YZ oriented perpendicular to the direction of rotation X. However, it is also conceivable that the maximum axial extent of the outer bearing ring is even greater than that of the shoulder of the first machine element to form the positive fit between the bypass holder and the first machine element.

The bypass device provides at least one electrical connection between the first and second machine elements. The design of the bypass device focuses solely on electrical conductivity and installation, not on sealing. When bypass conductors are integrated into sealing systems, compromises must be made regarding the material properties of both the seals and the bypass conductor. When designing the bypass conductor of a bypass device, it is advantageous to consider only the requirements for electrical conductivity and wear resistance when selecting and designing the material.

The bypass device consists of a holder and an electrically conductive bypass conductor. The holder is a component of any design suitable for holding the bypass conductor within the rolling bearing. The properties of the bypass conductor can be precisely tailored to the specific through-resistance or discharge resistance of the rolling bearing.

As mentioned previously, the holder and the bypass conductor are electrically connected, with the holder itself typically being conductive. Generally, the bypass device is designed so that voltage potentials are discharged via this bypass device and not via the cylinder roller assembly.

Two machine elements are rotatably mounted relative to each other using at least one set of cylindrical roller bearings. In this case, the second machine element is rotatably mounted about the axis of rotation of the rolling bearing by means of the cylindrical roller bearing set, while the first machine element is statically mounted, i.e., not rotatable. Machine elements are generally shafts, for example, rotor shafts of an electric machine; housings, for example, bearing shields or housings or housing sections or bearing shields of an electric machine; gears or shafts or housings of a gearbox; or any other machine elements suitable for being mounted relative to each other by means of rolling bearings.

In the cases considered, the axis of rotation of the cylindrical roller set is always axially aligned. Radial alignment is perpendicular to the axis of rotation.

The cylindrical roller set serves for the rotatable mounting of machine parts, elements and assemblies and has cylindrical rolling elements to reduce friction, which roll between the inner and outer bearing rings and thus reduce friction in the rotatable mounting.

The cylindrical roller assembly can have a cage to guide the rolling elements and, as previously described, is assembled with an inner and an outer bearing ring to form a rolling bearing. Alternatively, the rolling bearing can also have more than one inner and/or outer ring. Furthermore, the bearing ring(s) can also be split and have a raceway or a portion thereof. On the radially inner contact partner, i.e., the inner ring, one or more outer raceways are formed, and correspondingly, one or more inner raceways are formed on the outer ring. The rolling elements that roll on the raceways are roller-shaped bodies. As mentioned previously, the rollers are often guided and held in cages. The rolling elements are either arranged in a single row in the circumferential direction or, alternatively, the arrangement consists of several rows of rolling elements side by side. The bearing rings can be manufactured with or without flanges.

In the context of the invention, a bypass is understood to mean the diversion of a current or voltage around one or more rolling bearings and/or machine components. The rolling elements and the bearing ring are usually made of bearing steel and contact each other at the raceway(s). The contact zones formed are potential pathways for currents, at which the dreaded discharges lead to the damage to the raceways already described in the chapter "Background of the Invention".

The bypass, or bypass device, is intended to divert the currents. This can be achieved, firstly, by ensuring that the bypass device, or at least the bypass conductor, has comparatively lower electrical or specific electrical resistances than the rolling bearing.

It is conceivable that the cylindrical roller set is insulated against current flow at the inner bearing ring. For example, it is conceivable that an insulator or insulating layer is applied between the first machine element on/in which the bearing ring sits. The holder of the bypass device is directly electrically connected to the first machine element, i.e., without an insulating layer or elements. It is conceivable that the rolling elements are made of a non-electrically conductive material such as ceramic. In this case, the bypass device only needs to divert the current.

In a further preferred embodiment, especially for so-called "wet" applications, i.e., where the lubricant of the overall system also serves as rolling bearing lubrication, the holder of the bypass device has media-permeable openings. These can be designed with different geometries and allow the passage of lubricant while simultaneously preventing excessively high, damaging contact pressure of the bypass line against the second machine element in the event of pressure differences occurring in the system. To ensure this, it may be necessary to provide these openings on all elements of a two-part or multi-part holder design, for example, a retaining disc and a clamping disc. This allows the lubricant to pass through the bypass device in an ideal manner.

In a further preferred embodiment, the retaining disc and the clamping disc are riveted together. This riveting creates media-permeable, annular openings that are available on the holder during application. This can be achieved by creating circular through-holes through the retaining disc and the clamping disc. This is particularly advantageous because the holder discs can be manufactured, i.e., joined, very efficiently in this way, while simultaneously creating media-permeable through-holes.

It is also conceivable that in another preferred embodiment the media-permeable openings simultaneously serve to make the holder elastic in such a way that it can clamp the bypass conductor particularly well.

While any material and design of the bypass conductor are conceivable, it can be advantageous to construct the bypass conductor from loop-stitched fibers. The term "stitched fibers," as used below, refers to individual fibers, fiber pairs, or fiber bundles. The term "stitching" describes any joining of the fibers, fiber pairs, or bundles that utilizes an additional thread for connection. Equivalent methods include sewing, crocheting, or similar techniques. A bypass conductor constructed in this way provides an ideal method for current transmission, even in contact with lubricants. Furthermore, it allows the flow of lubricant without causing pressure differentials in the bearing or the overall system.

The looped, interwoven fibers of the bypass conductor in the rolling bearing assembly can contain carbon or carbon derivatives. These components are particularly suitable for conducting current in a bypass conductor of a rolling bearing assembly because they are characterized by high elasticity with high elongation at break and very good electrical conductivity.

The aforementioned alloy can alternatively be formed from a copper-tin alloy, a tin-silver alloy, a tin-zinc alloy, a tin-bismuth alloy, a tin-antimony alloy, a tin-cobalt alloy, a nickel-tungsten alloy, or a tin-manganese alloy.

SnCu, in particular, has proven to be a high-performance material composition for a contact surface of a bypass device.

The first layer is made of copper or nickel. This ensures good adhesion of the layer system to the base material of the first machine element, i.e., the metal substrate.

The non-metallic particles preferably comprise a proportion of electrically conductive particles, which cause a significant reduction in the interfacial resistance of the component and are in particular formed from at least one material of the group comprising carbon, graphite, carbon nanotubes, carbon fibers, carbon black, graphene, graphene oxide, metal nitride, metal carbide.

The proportion of electrically conductive particles can be more than 50% of the non-metallic particles. It has been shown that the electrically conductive particles protruding from the second layer maintain the electrical contact between the contact surface of the first machine element and the bypass conductor particularly reliably.

A combination of a tin-nickel alloy with a nickel content in the range of 20 to 40 wt% with dispersed non-metallic particles of at least one material from the group comprising carbon, graphite, carbon nanotubes, carbon fibers, carbon black, graphene, and graphene oxide. This alloy forms an oxide layer on its surface as passivation; however, this layer is itself conductive and improves the start-up behavior of rotating machine elements.

The non-metallic particles may also include a proportion of particles formed from a non-electrically conductive material, such as at least one material from the group comprising metal sulfide, metal oxide, diamond, mica, PTFE.

Preferably used metal oxides include Al₂O₃, BeO₂, CdO, MgO, SiO₂, TiO₂, ZrO₂, Fe oxides, and the like. Preferably used metal carbides include SiC, WC, VC, TiC, Cr₂C₃, Cr₃C₂, and the like. Preferably used metal nitrides include BN or SiN and the like. Carbon is particularly preferred in the form of graphite, carbon nanotubes, carbon fibers, carbon black, graphene, or graphene oxide. Preferably used metal sulfides include MoS₂, MoS₂, Ni-FeS₂, and the like.

A particularly suitable particle size for the non-metallic particles lies in the range of 100 nm to 8 µm, especially in the range of 500 nm to 6 µm. Particles that are particularly stable when dispersed in an electrolyte for the electroplating of the second layer are especially preferred. In particular, the particle size is selected such that it protrudes from the surface of the at least one second layer to ensure contact with the counterbody.

A volume fraction of non-metallic particles in the second layer, ranging from 1 to 50 vol.%, is also particularly suitable. This ensures reliable binding of the particles within the metallic matrix.

The optional first layer and at least one second layer are formed by electroplating. Electroplating processes readily allow the deposition of electrolyte-dense layers with a thickness of up to 30 µm. This enables the creation of electroplated, conductive, and durable layers on metallic substrates such as bearing steels or similar materials. The non-metallic particles are dispersed in an electrolyte to form the second layer and are incorporated into the alloy deposited on the first layer, forming at least one second layer.

A single second layer or several second layers can be applied on top of each other.

Furthermore, electroplating can be carried out using a so-called "pulse plating" process, in which the voltage applied to the electrolyte is periodically switched off or reversed. The brief current pulses received during the switch-on process create more nuclei for metal deposition, thus providing a basis for fine-grained deposits and a glossy finish.

The first layer preferably has a thickness of up to 5 µm, particularly up to 3 µm. The at least one second layer preferably has a thickness of up to 30 µm, particularly between 5 and 20 µm. The preferred total thickness of the layer system is < 10 µm, particularly between 4 and 8 µm.

Description of the drawings

• - 1 - ein Teilschnitt als Ausführungsbeispiel einer Wälzlageranordnung 1 in einem Teilschnitt entlang der Rotationsachse 16;
• - 2 - eine Detaildarstellung der Wälzlageranordnung aus 1 in einem schrägen Teilschnitt;
• - 3 - einen Ausschnitt des Kontaktbereichs des zweiten Maschinenelements 31 aus 1 im Schnittbild im I-I;

The invention is explained in more detail below using exemplary embodiments. The figures show:

• - 1 - a partial section as an embodiment of a rolling bearing arrangement 1 in a partial section along the axis of rotation 16;
• - 2 - a detailed representation of the rolling bearing arrangement from 1 in a slanted partial section;
• - 3 - a section of the contact area of the second machine element 31 from 1 in the cross-sectional view in II;

1 The rolling bearing arrangement 1 is formed from the cylindrical roller assembly 5, a static inner bearing ring 7, a rotatable outer bearing ring 2, and a bypass device 20, and comprises a first machine element 30 and a second machine element 31, shown schematically. The second machine element 31 can, for example, be designed as a housing, and the first machine element 30, for example, as a shaft or hollow shaft 9. The cylindrical roller assembly 5 comprises a plurality of cylindrical rollers 8 and can include a cage 11. The bearing ring 2 is arranged concentrically on an axially oriented axis of rotation 16 of the cylindrical roller assembly 5. The cylindrical roller assembly 5 is provided with cylindrical rollers 8 arranged radially between the inner bearing ring 7 and the outer bearing ring 2, the latter being oriented radially transversely to the axis of rotation 16. An electrical connection between the first machine element 30 and the second machine element 31 is formed via the bypass device 20, through the outer bearing ring. The bypass device 20 shows in 1 The device comprises a holder 21 and an electrically conductive bypass conductor 23, the holder 21 and bypass conductor 23 being electrically connected to each other. The holder 21 is axially secured by a positive fit between the inner bearing ring 7 and a shoulder in the first machine element 30, the inner bearing ring 7 being attached to the first machine element 30. A bearing space 19 is formed between the inner bearing ring 7 and the outer bearing ring 2. A contact area 14 is formed on the outer bearing ring 2, extending radially inwards towards the bearing space 19, in which the electrical contact between the bypass conductor 23 and the outer bearing ring 2 is formed. In this area, the bypass conductor 23 contacts the contact area 14 radially. The holder 21 of the bypass device 20 also engages radially in a groove-shaped undercut 28 between the inner bearing ring 7 and the first machine element 30. The groove-shaped undercut 28 is ideally a circumferential groove that exposes the area of the holder 21 that overlaps with the inner bearing ring 7. Thus, contact between the holder 21 and the inner bearing ring 7 occurs in the area of the bearing shoulder 9, and between the holder 21 and the first machine element 30 on the radially inner side of the holder 21. The holder 21 is in 1 The bypass conductor 23 is formed in two parts, with a retaining disc 21.1 and a clamping disc 21.2 ensuring secure retention. As shown in the figure, the outer bearing ring 2 on side A of the bypass device 20 can have a greater axial extension than on the opposite side B.

2 - The holder 21 of the bypass device 20 of the rolling bearing arrangement 1 has in 2 The holder 21 features annular openings 24. This is particularly advantageous for so-called "wet" applications, i.e., where the lubricant of an entire system also serves as rolling bearing lubrication. The annular openings 24 on the holder 21 are media-permeable openings. These can be designed with different geometries, i.e., distributed around the circumference of the holder in different annular segments or sub-segments, or as circular openings as in the following example. 2 , and allow the passage of lubricant and at the same time prevent excessively high, damaging contact pressure of the bypass conductor 23 on the second machine element 31 in the event of pressure differences occurring in the system. 2 This also shows that the retaining disc 21.1 and the clamping disc 21.2 can be riveted together. The riveting creates media-permeable, annular openings 10, which are available on the holder 21 during application. Thus, the riveting creates annular through-holes 10 through the retaining disc 21.1 and the clamping disc 21.2.

3 - 3 shows the contact area 14 of the second machine element 31 1 In section II, the base material 6 is visible, here, for example, bearing steel. The contact surface, or contact area 14, represents the area in contact with the bypass conductor 23. The first machine element 31 has a coating 3, which is electroplated with a first layer 3a of nickel, for example, with a layer thickness of 1 µm. On the first layer 3a is an electroplated second layer 3b made of a tin-nickel alloy containing non-metallic graphite particles with a layer thickness of, for example, 5 µm.

Reference sign

1

rolling bearing arrangement

2

Outer bearing ring

3

coating

3a

First shift

3b

Second shift

4

Paragraph in the first machine element

5

Cylinder roller set

6

Basic material

7

Inner bearing ring

8

Cylinder rollers

9

Bearing shoulder

10

ring-shaped openings created by caulking

11

cage

12

-

13

-

14

Contact area

15

-

16

axis of rotation

17

-

18

-

19

Storage space

20

Bypass device

21

Holder of the bypass device

21.1

retaining disc

21.2

Clamping disc

22

-

23

Bypass ladder

24

Ring-shaped openings

25

-

26

-

27

-

28

-

29

-

30

first machine element

31

second machine element

32

-

33

-

34

-

Claims (6)

A rolling bearing arrangement (1) comprising at least one set of cylindrical rollers (5), a static inner bearing ring (7), a rotatable outer bearing ring (2), and a bypass device (20), and further comprising a first machine element (30) and a second machine element (31), wherein: - the set of cylindrical rollers (5) comprises a plurality of cylindrical rollers (8), and - the cylindrical rollers (8) of the set of cylindrical rollers (5) are arranged radially between the inner bearing ring (7) and the outer bearing ring (2), and are directed radially transversely to the axis of rotation (16), - the inner bearing ring (7) and the outer bearing ring (2) are arranged concentrically on an axially oriented axis of rotation (16) of the rolling bearing arrangement (1), - at least one electrical connection is formed between the first machine element (30) and the second machine element (31) via the bypass device (20), - the bypass device (20) has a holder (21) and has at least one electrically conductive bypass conductor (23), and wherein the holder (21) and bypass conductor (23) are electrically connected to each other, - the holder (21) is axially secured by a positive fit between the inner bearing ring (2) and a shoulder in the first machine element (30) and holds the bypass conductor (23), - wherein the inner bearing ring (2) is attached to the first machine element (30), - wherein a bearing space (19) is formed between the inner bearing ring (7) and the outer bearing ring (2), - wherein a contact area (14) is formed on the outer bearing ring (2) extending radially inwards towards the bearing space (19), at which the electrical contact between the bypass conductor (23) and the outer bearing ring (2) is formed, - and wherein the bypass conductor (23) radially contacts the contact area (14), - wherein the contact area (14) is located on the second machine element (31) Electroplated layer system (3) comprising, the layer system (3) optionally comprising a first layer (3a) arranged on the second machine element (5) and at least one second layer (3b) arranged on the second machine element (5) or, if present, on the first layer (3a), wherein the optional first layer (3a) is formed of copper or nickel and the at least one second layer (3b) is formed of an alloy comprising at least two of the elements tin, copper, nickel, silver, zinc, bismuth, antimony, cobalt, manganese, tungsten, wherein non-metallic particles comprising electrically conductive particles are incorporated in the alloy and wherein the alloy of the second layer is formed of a tin-nickel alloy with a nickel content in the range of 20 to 40 wt.%. Rolling bearing arrangement (1) according Claim 1 , wherein the holder (21) of the bypass device (20) is designed in two parts, comprising a retaining disc (21.1) and a clamping disc (21.2). Rolling bearing arrangement (1) according Claim 1 , wherein the holder (21) of the bypass device (20) also engages radially in a groove-shaped undercut (28) on the inner bearing ring (7) between the inner bearing ring (7) and the first machine element (30). Rolling bearing arrangement (1) according to one of the preceding claims, wherein the outer bearing ring has a greater extent in the axial direction (A) of the bypass device (20) than on the opposite side (B). Rolling bearing arrangement (1) according to one of the preceding claims, wherein the holder (21) of the bypass device (20) has media-permeable annular openings (10, 24). Rolling bearing arrangement (1) according Claim 2 until 5 , wherein the retaining disc (21.1) and the clamping disc (21.2) are riveted together and the riveting creates media-permeable annular openings (10).