DE102020105305A1 - Roller bearing arrangement - Google Patents

Abstract

The invention relates to a rolling bearing arrangement (1), comprising a rolling bearing (2) with an inner ring (3), an outer ring (4), rolling elements (5) and a cage (6), the inner ring (3) having an inner ring raceway (7) and the outer ring (4) has an outer ring raceway (8), the rolling elements (5) being mounted between the inner ring (3) and the outer ring (4) in a rolling manner in the cage (6) and spaced apart from one another, between the inner ring (3) and an electrically conductive element (9) is arranged on the outer ring (4), which electrically connects the inner ring (3) to the outer ring (4). According to the invention, the electrically conductive element (9) is designed as a plurality of annular disk-like hollow rollers (10) which are an inner ring-side guide groove (11) and an outer-ring-side guide groove (12) between the inner ring (3) and the outer ring (4) in a hollow roller cage (13) are guided in a rolling manner at a distance from one another.

Description

The invention relates to a rolling bearing arrangement, comprising a rolling bearing with an inner ring, an outer ring, rolling elements and a cage, the inner ring having an inner ring raceway and the outer ring having an outer ring raceway, the rolling elements being arranged between the inner ring and the outer ring in a rolling manner in the cage , wherein an electrically conductive element is arranged between the inner ring and the outer ring, which connects the inner ring to the outer ring in an electrically conductive manner.

When using rolling bearings, e.g. in or on electrical machines or within a hybridized drive train of a motor vehicle, current can pass through. The switching pulses from converters lead, for example, to the build-up of voltage between the bearing rings of rolling bearings. This tension is relieved again and again by breakdowns. Under unfavorable conditions, this can lead to current passage damage to raceways and rolling elements. There is thus the risk of a premature and unexpected failure of the bearing and thus of the entire electrical machine. In addition to the increased maintenance effort, the downtime of the machine results in additional costs.

Current-insulated rolling bearings which are intended to prevent harmful bearing currents are known from the prior art. For example, rolling bearings with ceramic insulation on the outer or inner ring are used. Current-insulated rolling bearings are, however, comparatively expensive and are therefore not used very often.

In light of the known prior art, it is therefore the object of the invention to provide a roller bearing arrangement with improved protection against harmful bearing currents. In particular, it is also the object of the invention to provide a roller bearing arrangement which realizes protection against harmful bearing currents in a wet-running roller bearing arrangement.

This object is achieved by a rolling bearing arrangement, comprising a rolling bearing with an inner ring, an outer ring, rolling elements and a cage, the inner ring having an inner ring raceway and the outer ring having an outer ring raceway, the rolling elements being supported by rolling in the cage and spaced apart from one another are arranged, wherein a current-conducting element is arranged between the inner ring and the outer ring, which electrically connects the inner ring to the outer ring, the current-conducting element is designed as a plurality of annular disk-like hollow rollers, which are located in a guide groove on the inner ring side and a guide groove on the outer ring side between the inner ring and the outer ring are guided rolling at a distance from each other in a hollow roller cage.

The object is also achieved by a roller bearing arrangement, comprising a roller bearing with an inner ring, an outer ring, rolling elements and a cage, the inner ring having an inner ring raceway and the outer ring having an outer ring raceway, the rolling elements between the inner ring and the outer ring being supported rollingly in the cage from one another are arranged spaced apart, a current-conducting element being arranged axially spaced apart from the inner ring and the outer ring, which element realizes a current transition between a shaft and a bearing housing accommodating the roller bearing.

As a result of the configuration according to the invention of a roller bearing arrangement, it can provide low-friction protection against harmful bearing currents. Furthermore, the configuration according to the invention is also suitable for use in wet-running roller bearings.

First, the individual elements of the claimed subject matter of the invention are explained in the order in which they are named in the set of claims and particularly preferred embodiments of the subject matter of the invention are described below.

Rolling bearings can in particular be used to transmit rotary movements with the lowest possible friction losses. Rolling bearings can be used in particular to fix axles and shafts, whereby, depending on the design, they absorb radial and / or axial forces and at the same time enable the rotation of the shaft or the components mounted on an axle in this way.

For this purpose, rolling elements are arranged between an inner ring and an outer ring of the roller bearing. Between these three main components, the inner ring, outer ring and the rolling elements, mainly rolling friction usually occurs within the rolling bearing. Since the rolling elements in the inner and outer ring can preferably roll on hardened steel surfaces with optimized lubrication, the rolling friction of such bearings is relatively low.

The inner ring can, in particular, connect the shaft that receives the roller bearings to the roller bearing or the roller bodies. In particular, the shaft can be connected to the side of the outer surface of the inner ring facing the shaft, with the rolling elements of the roller bearing rolling on the inner ring raceway opposite this outer surface. The inner ring can be formed from a metallic and / or ceramic material. It is basically conceivable to design the inner ring in one piece or in several parts, in particular in two parts.

The outer ring can in particular connect the bearing receiving the roller bearing to the roller bearing or the roller bodies. In particular, the bearing can be connected to the side of the outer ring surface facing the bearing, with the outer ring raceway opposite this outer ring rolling the rolling elements of the rolling bearing. The outer ring can be formed from a metallic and / or ceramic material. It is basically conceivable to design the outer ring in one piece or in several parts, in particular in two parts.

The rolling elements have the shape of a ball or a roller, depending on the type of rolling bearing. They roll on the raceways of the rolling bearing and have the task of transferring the force acting on a radial rolling bearing from the outer ring to the inner ring and vice versa. In an axial rolling bearing, the rolling elements transmit the forces acting on the axial rolling bearing between the running disks. Roller-shaped rolling bodies are also referred to as roller-rolling bodies and spherical rolling bodies as bearing balls.

A roller bearing can have a cage, the cage guiding the rolling elements. The cage is designed in such a way that the rolling element balls and / or the rolling element rollers are spaced apart from one another so that, for example, the friction and heat generation of the rolling elements is kept as low as possible. Furthermore, the cage keeps the rolling element balls and / or rolling element rollers at a fixed distance from one another when they roll, as a result of which a uniform load distribution can be achieved. The cage can be made in one piece or in several pieces.

The rolling elements can roll inside the rolling bearing, in particular on the inner ring raceway of the inner ring. For this purpose, the surface of the inner ring raceway can advantageously be made correspondingly wear-resistant, for example also by means of a corresponding surface treatment method and / or by applying a corresponding additional material layer. The inner ring raceway can be flat or profiled. A profiled design of the inner ring raceway can be used, for example, to guide the rolling elements on the inner ring raceway. A planar shape of the inner ring raceway can, however, allow, for example, a certain axial displaceability of the rolling bodies on the inner ring raceway.

The rolling bodies can roll within the rolling bearing, in particular on the outer ring raceway of the outer ring. For this purpose, the surface of the outer ring raceway can advantageously be made correspondingly wear-resistant, for example also by means of a corresponding surface treatment method and / or by applying a corresponding additional material layer. The outer ring raceway can be flat or profiled. A profiled configuration of the outer ring raceway can be used, for example, to guide the rolling elements on the outer ring raceway. A planar formation of the outer ring raceway can, however, allow, for example, a certain axial displaceability of the rolling bodies on the outer ring raceway.

According to a preferred embodiment of the invention, it can be advantageous that the hollow rollers are guided between the inner ring and the outer ring without play. In this way, the electrical contact between the inner ring, the outer ring and the hollow rollers that is necessary for conducting current can be ensured.

It can furthermore be advantageous for the roller bearing to have two current-conducting elements, which are preferably arranged on both sides of the roller bodies, as a result of which the security against harmful current flows can be further increased.

In a further development of the invention, it can furthermore be preferred that the hollow roller is pretensioned. This measure, too, can further improve the operational reliability of the current-conducting element, since the electrical contact between the hollow rollers and the grooves receiving the hollow rollers can be adequately ensured by the prestressing.

Furthermore, it can be advantageous that the hollow rollers and the guide groove on the inner ring side and the guide groove on the outer ring side are configured in such a way that no lubricating film forms on the contact surfaces of the hollow rollers with the guide groove on the inner ring side and the guide groove on the outer ring side. This prevents a lubricating film from being formed on the electrical contact surfaces, which could reduce the electrical conductivity of the electrically conductive element.

According to a further advantageous embodiment of the invention, it can be preferred that the hollow rollers have a coating that provides improved wear protection and / or improved current transfer.

• 1 eine erste Ausführungsform einer erfindungsgemäßen Wälzlageranordnung in einer schematischen Querschnittsansicht,
• 2 eine zweite Ausführungsform einer erfindungsgemäßen Wälzlageranordnung in einer schematischen Querschnittsansicht, und
• 3 eine dritte Ausführungsform einer erfindungsgemäßen Wälzlageranordnung in einer schematischen Querschnittsansicht.

The invention will be explained in more detail below with reference to figures without restricting the general inventive concept. The figures are merely of a schematic nature and are used exclusively for understanding the invention. The same elements are provided with the same reference symbols. The different features of the various exemplary embodiments can be freely combined with one another within what is technically feasible. Show it:

• 1 a first embodiment of a roller bearing arrangement according to the invention in a schematic cross-sectional view,
• 2 a second embodiment of a roller bearing arrangement according to the invention in a schematic cross-sectional view, and
• 3 a third embodiment of a roller bearing arrangement according to the invention in a schematic cross-sectional view.

the 1 shows a roller bearing arrangement 1 , comprising a roller bearing 2 with an inner ring 3 , an outer ring 4th , Rolling elements 5 and a cage 6th , the inner ring 3 an inner ring raceway 7th has and the outer ring 4th an outer ring raceway 8th having. The rolling elements 5 are between the inner ring 3 and outer ring 4th stored rolling in the cage 6th arranged spaced from each other. Between the inner ring 3 and the outer ring 4th is an electrically conductive element 9 arranged which the inner ring 3 with the outer ring 4th electrically connects. The conductive element 9 has a plurality of annular disk-like hollow rollers 10 , which in a guide groove on the inner ring side 11 and a guide groove on the outer ring side 12th between inner ring 3 and outer ring 4th in a hollow roller cage 13th are guided rolling at a distance from each other. The hollow rollers 10 are free of play between the inner ring 3 and outer ring 4th guided. It goes without saying that the hollow rollers 10 are formed from an electrically conductive material.

the 1 also shows that the hollow rollers 10 and the guide groove on the inner ring side 11 as well as the guide groove on the outer ring side 12th are configured such that on the contact surfaces of the hollow rollers 10 with the guide groove on the inner ring side 11 and the guide groove on the outer ring side 12th no lubricating film forms. This can be achieved, for example, by the freedom from play mentioned above and / or a pretensioning of the hollow rollers 10 be realized.

the 2 shows a second embodiment of the invention in which the roller bearing 2 two conductive elements 9 has on both sides of the rolling elements 5 are arranged. In the example shown are the conductive elements 9 essentially formed identically. The conductive elements shown 9 correspond to those from the 1 already acquaintances.

the 3 finally shows a third embodiment of the invention, in which the roller bearing arrangement 1 a roller bearing 2 with an inner ring 3 , an outer ring 4th , Rolling elements 5 and a cage 6th comprises, wherein the inner ring 3 an inner ring raceway 7th has and the outer ring 4th an outer ring raceway 8th having. The rolling elements 5 are between the inner ring 3 and outer ring 4th stored rolling in the cage 6th arranged spaced from each other. Each axially from the inner ring 3 and the outer ring 4th at a distance is an electrically conductive element 14th is arranged, which is a current transition between a shaft, not shown, and the roller bearing 2 realized receiving bearing housing. This conductive element 14th essentially corresponds to that from 1 known conductive element 9 so that a new description can be dispensed with. Unlike in the embodiment of the 1 has the conductive element 14th here, however, a separate inner ring 15th and a separate outer ring 16 on. The conductive element 14th can be arranged at any suitable point between the shaft and the bearing housing.

The invention is not limited to the embodiments shown in the figures. The above description is therefore not to be regarded as restrictive, but rather as explanatory. The following patent claims are to be understood in such a way that a named feature is present in at least one embodiment of the invention. This does not exclude the presence of further features. If the patent claims and the above description define “first” and “second” features, this designation serves to distinguish between two similar features without defining an order of precedence.

List of reference symbols

1

Roller bearing arrangement

2

roller bearing

3

Inner ring

4th

Outer ring

5

Rolling elements

6th

Cage

7th

Inner ring raceway

8th

Outer ring raceway

9

conductive element

10

Hollow rollers

11

inner ring side guide groove

12th

outer ring side guide groove

13th

Hollow roller cage

14th

conductive element

15th

Inner ring

16

Outer ring

Claims (7)

Rolling bearing arrangement (1) for a rolling bearing (2) with an inner ring (3), an outer ring (4), rolling elements (5) and a cage (6), the inner ring (3) having an inner ring raceway (7) and the outer ring ( 4) has an outer ring raceway (8), the rolling elements (5) between the inner ring (3) and the outer ring (4) being mounted in the cage (6) in a rolling manner and spaced apart from one another, with the inner ring (3) and the outer ring (4 ) an electrically conductive element (9) is arranged, which electrically connects the inner ring (3) to the outer ring (4), characterized in that the electrically conductive element (9) is designed as a plurality of ring-disk-like hollow rollers (10) which in an inner ring-side Guide groove (11) and an outer ring-side guide groove (12) between the inner ring (3) and outer ring (4) are guided in a hollow roller cage (13) and are spaced apart from one another and rolling. Rolling bearing arrangement (1), according to Claim 1 , characterized in that the hollow rollers (10) are guided without play between the inner ring (3) and the outer ring (4). Rolling bearing arrangement (1) according to one of the preceding claims, characterized in that the rolling bearing (2) has two current-conducting elements (9) which are preferably arranged on both sides of the rolling bodies (5). Rolling bearing arrangement (1) according to one of the preceding claims, characterized in that the hollow roller (10) is preloaded. Rolling bearing arrangement (1) according to one of the preceding claims, characterized in that the hollow rollers (10) and the guide groove (11) on the inner ring side and the guide groove (12) on the outer ring side are configured in such a way that on the contact surfaces of the hollow rollers (10) with the inner ring-side guide groove (11) and the outer-ring-side guide groove (12) do not form a lubricating film. Rolling bearing arrangement (1) according to one of the preceding claims, characterized in that the hollow rollers (10) have a coating which provides improved wear protection and / or an improved current transfer. Rolling bearing arrangement (1), comprising a rolling bearing (2) with an inner ring (3), an outer ring (4), rolling elements (5) and a cage (6), the inner ring (3) having an inner ring raceway (7) and the outer ring (4) has an outer ring raceway (8), the rolling elements (5) between the inner ring (3) and the outer ring (4) being supported by rolling in the cage (6) and spaced apart from one another, each being axially spaced from the inner ring (3) and the A current-conducting element (14) is arranged at a distance from the outer ring (4) and realizes a current transfer between a shaft and a bearing housing that accommodates the roller bearing (2).

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