Rolling bearing

Abstract

The present invention relates to a rolling bearing, preferably a centreless large roller bearing, comprising: two concentric bearing rings which can rotate relative to one another; at least one row of rolling elements which support the bearing rings against one another and roll on raceways of the bearing rings; and a cage having separators between the rolling elements for separating and guiding the rolling elements, the separators being positioned eccentrically offset relative to one of the raceways with respect to a bearing clearance central axis along which the rolling elements are arranged in such a way that their axes of rotation are distributed relative to one another.

Description

[0001] Rolling bearings

[0002] The present invention relates to rolling bearings with two concentric, mutually rotatable bearings, at least one row of rolling elements which support the bearing rings against each other and roll on raceways of the bearing rings, as well as a cage with separating webs between the rolling elements for separating and guiding the rolling elements.

[0003] Such rolling bearings can be, for example, slewing bearings, especially centerless slewing bearings, which can have ring diameters of more than 0.5 m, more than 1 m, or even more than 2 m. Such slewing bearings can be used, for example, in wind turbines for supporting the rotor hub or for supporting the rotor blades on the rotor hub. Such slewing bearings can be single-row or multi-row and comprise radial and / or axial bearing rows.

[0004] Such rolling bearings can also be single-row tapered roller bearings. Alternatively, such bearings can also be multi-row tapered roller bearings or other rolling elements, for example in the form of balls, cylindrical rollers, or spherical rollers, or hybrid forms in the sense of bearing rows made up of different rolling element shapes. One aim of such rolling bearings is to accommodate the largest possible number of rolling elements in a bearing row, with a ring diameter usually determined by the installation environment, in order to distribute the sometimes high loads across as many rolling elements as possible and achieve an overall rigid bearing arrangement.For example, center-free slewing bearings are often subjected not only to high forces but also to high bending moments, for example when used as rotor blade bearings on a wind turbine or as slewing gear bearings on a crane, so that the bearing rings tend to twist and the rolling elements are subjected to very high loads in one sector and can lift off in an opposite sector.

[0005] However, a densely packed arrangement of rolling elements with a large number of rolling elements in a bearing row sometimes complicates assembly. This also makes it difficult to accommodate the bearing cage, which keeps the rolling elements spaced apart and guides them during rolling along the raceways on the bearing rings, particularly when the rolling elements must be closely spaced to accommodate a large number of rolling elements.

[0006] A densely packed arrangement of the rolling elements with small distances between the rolling elements can also impair the stability or rigidity of the cage, since the separating webs between the rolling elements must be designed to be correspondingly narrow or thin-walled in order to enable small rolling element distances.

[0007] Against this background, the present invention is based on the object of creating an improved rolling bearing of the aforementioned type that avoids the disadvantages of the prior art and advantageously develops them further. In particular, the aim is to enable the highest possible number of rolling elements in a bearing row without sacrificing ease of assembly and sufficient cage rigidity.

[0008] According to the invention, the stated object is achieved by a rolling bearing according to claim 1. Preferred embodiments of the invention are the subject of the dependent claims. It is therefore proposed to position the separating webs of the cage eccentrically and no longer arrange them exactly at the level of the axes of rotation of the rolling elements. According to the invention, the separating webs are arranged eccentrically offset toward one of the raceways relative to a central axis of the bearing gap, along which the rolling elements are arranged with their axes of rotation.

[0009] Due to the eccentrically offset arrangement of the separators, they are no longer equally spaced from the two raceways on which the rolling elements roll, but are positioned closer to one raceway. The distance between the separators and one of the two raceways is smaller than the distance between the separators and the other of the two raceways.

[0010] Due to the eccentrically offset arrangement of the separators, they are located in an area between two rolling elements with more space, so that the separators can be adequately dimensioned even when the rolling elements are closely packed. At the level of the rolling element rotation axes, the rolling elements are at their closest distance from each other, while the space between two rolling elements widens from the bearing gap center axis towards both raceways, so that the separators come to lie in the widening area due to the eccentrically offset arrangement. At the same time, the eccentrically offset arrangement allows the separators to hold the rolling elements on one of the bearing rings during assembly or disassembly of the rolling element, particularly on the raceway from which the separators are further spaced.

[0011] In a further development of the invention, the distance of the separating webs from one of the raceways can be more than 150% or even more than 200% of the distance from the other raceway.

[0012] In particular, the separating webs can be arranged at approximately 2 / 3 to approximately 3 / 4 of the clearance height of the bearing gap between the two raceways. The clearance height refers to the distance between the two raceways, measured in a direction perpendicular to the rotational axis of a rolling element. For raceways that are inclined relative to each other, such as the raceways of a tapered roller bearing row, the distance can be measured, for example, perpendicular to the rolling bearing's rotational axis in the center of the rolling elements.

[0013] The separating webs can advantageously have a circular cross-section and a substantially constant diameter along their length, so that the separating webs can form cylindrical rods overall. Alternatively, the separating webs can also have a diameter or thickness that varies along their length, for example, continuously increasing in thickness or diameter from one axial end to the opposite axial end. If the separating webs have a circular cross-section, the separating webs can be slightly conical in shape overall.

[0014] The dividers can also have a cross-section that deviates from circular, for example, they can have a trapezoidal, triangular, polygonal, or polygonal contour when viewed in cross-section. The dividers can have a constant diameter or a varying diameter over their length, for example, they can continuously increase in diameter from one axial end to the opposite axial end.

[0015] However, depending on the shape of the rolling elements, the separating webs can also have other contours, for example an hourglass-like contour and thicken from a thin central section towards both axial ends, for example when balls or barrels are used as rolling elements.

[0016] In an advantageous development of the invention, the contour of the separating webs is adapted to the contour of the rolling elements to be guided in order to achieve the desired contact geometry and the desired friction behavior between the rolling elements and the cage or separating webs.

[0017] Regardless of the contour of the separators, the cage can be designed to hold the rolling elements with the separators on one of the bearing rings, so that the bearing ring, together with the rolling elements and the cage, forms a pre-assembled assembly. The cage with the separators holds the rolling elements or the roller set on the respective raceway, so that the raceway can be handled as a unit together with the bearing row without the rolling elements falling off the bearing, even if the bearing has been disassembled or not yet assembled with the other bearing.

[0018] In a further development of the invention, the raceway of the bearing ring, on which the roller set is held by the cage, can be designed with a groove-shaped recess or be enclosed laterally by projecting side walls or guide projections, so that the rolling elements cannot slip off the raceway in the direction of their axis of rotation when they are held on the raceway by the separating webs. Depending on the contour of the rolling elements, the said raceway can also be designed with a groove-shaped recess or, viewed in cross-section, harmoniously curved, for example when using balls or ball-shaped contoured barrels, so that the rolling elements, when held on the raceway by the cage, cannot slip off the raceway transversely, i.e. in the direction of the axes of rotation.

[0019] In a further development of the invention, the two raceways can have different raceway diameters and the separating webs can be further spaced from the raceway with the smaller raceway diameter than from the raceway with the larger raceway diameter.

[0020] In particular, the cage can hold the rolling elements of a bearing row on the inner ring. The separators can be positioned closer to the outer ring raceway and spaced further apart from the inner ring raceway, allowing the eccentrically arranged separators to hold the rolling elements on the inner ring.

[0021] To facilitate easy assembly, the cage can be designed in a differential configuration. For example, the separating webs can be mounted or attached to at least one cage ring extending along the bearing gap. In particular, the cage can comprise two cage rings, to which the separating webs are mounted or attached at opposite axial ends and which are connected to one another by said separating webs.

[0022] For example, the separating webs can be joined to the at least one cage ring by a suitable joining method, wherein, for example, a plug-in connection or a detachable fastening of the separating webs to the cage ring can be provided.

[0023] In a further development of the invention, the separators can be connected to the cage rings while the rolling elements are already resting on the raceway and the separators are positioned between adjacent rolling elements. This considerably simplifies assembly.

[0024] After the separators have been installed and connected to the cage rings, the rolling element set, together with the cage and the bearing ring, forms a functional unit in which the rolling elements are held on the bearing ring.

[0025] The cage guidance can be achieved via the rolling elements or one of the bearing rings, for example the inner ring or the outer ring, or via both bearing rings or by a combination of the aforementioned components, for example via the rolling elements and one of the bearing rings, for example the inner ring.

[0026] The invention is explained in more detail below using a preferred embodiment and the accompanying drawings. In the drawings:

[0027] Fig. 1: a sectional view of a rolling bearing according to an advantageous embodiment of the invention, wherein a half-section through the axis of rotation of a rolling element is shown, which illustrates the eccentrically offset arrangement of the separating webs of the cage, Fig. 2: a perspective sectional view through the pre-assembled functional unit comprising the inner ring, the roller set and the cage of the rolling bearing from Fig. 1, wherein the holding function of the cage, which holds the roller set on the inner ring, is illustrated,

[0028] Fig. 3: a perspective view of the rolling element set together with the cage, illustrating the arrangement of the separating webs relative to the rolling elements,

[0029] Fig. 4: a perspective view of the roller set together with the cage from the previous figures, and

[0030] Fig. 5: a perspective view of the cage without rollers.

[0031] As shown in Fig. 1, the rolling bearing 1 can be designed as a single row, for example, in the form of a tapered roller bearing or an angular contact cylindrical roller bearing. However, the bearing can also be designed as a double or multi-row bearing and have one or more rows of radial bearings and / or one or more rows of axial bearings.

[0032] As shown in Fig. 1, the rolling bearing comprises two bearing rings 2 and 3, of which one bearing ring can form an inner ring 2 and the other bearing ring an outer ring 3. The bearing rings can be formed in one piece or in multiple pieces, for example, segmented or split.

[0033] As Fig. 1 shows, the rolling elements 11 of the rolling element bearing row 4 run on the raceways 5 and 6 of the bearing rings 2 and 3, so that the bearing rings 2 and 3 are rotatable relative to each other and are supported against each other by the rolling element bearing row 4.

[0034] The raceways 5 and 6 can be inclined at an acute angle to the axis of rotation 17 of the bearing rings 2, 3, so that a main bearing direction perpendicular to the axis of rotation 12 of the rolling elements 11 comprises both a radial component and an axial component.

[0035] As the figures show, the rolling elements 11 of the bearing row 4 are guided by a cage 7 and kept at a distance from one another, wherein the cage 7 comprises a plurality of separating webs 10, each of which extends between two adjacent rolling elements 11, cf. Figs. 3 and 4.

[0036] The said separating webs 10 can be contoured in the form of elongated bar profiles and, for example, have a cylindrical shape.

[0037] Independently of this, the separating webs 10 can extend between two cage rings 8 and 9 and connect them to each other. The separating webs 10 can be attached to the cage rings 8 and 9 by a suitable joining method, whereby, for example, the cage rings 8 and 9 can have plug-in recesses into which the separating webs 10 can be inserted, see Fig. 1.

[0038] The said cage rings 8 and 9 can extend on opposite sides of the rolling elements 11, in particular on opposite end faces at which the axes of rotation 12 of the rolling elements 11 emerge from the latter - conceptually, see Fig. 1.

[0039] As Figures 1 and 3 show, the separating webs 10 are arranged eccentrically offset relative to the center axis 14 of the bearing gap 13, relative to one of the raceways 6. In particular, the separating webs 10 can be arranged offset relative to the outer ring 3, so that the distance of the separating webs 10 from the outer ring raceway 6 is smaller than the distance from the inner ring raceway 5.

[0040] For example, the separating webs 10 can be arranged at approximately 2 / 3 to 3 / 4 of the clear height of the bearing gap 13, see Fig. 1.

[0041] Due to this eccentrically offset arrangement of the separating webs 10, the latter have more space between the adjacent rolling elements 11, since they are no longer arranged in the area of ​​the smallest gap between two adjacent rolling elements 11. The smallest gap between two adjacent rolling elements

[0042] 11 is present in the area of ​​the bearing gap center axis 14, which is positioned approximately centrally between the raceways 5 and 6 and along which the rotation axes

[0043] 12 of the rolling elements 11 move when the rolling elements 11 roll on the raceways 5, 6. At the level of the rotation axes 12, the rolling elements 11 come closest to each other.

[0044] On the other hand, the cage 7 with the separating webs 10 can hold the rolling elements 11 of the bearing row 4 on one of the bearing rings 2, 3, in particular on the inner ring 2, so that the inner ring 2 together with the roller set and the cage 7 can form a pre-assembled functional unit, as shown in Fig. 2.

[0045] Advantageously, the raceway 5 of the bearing ring 2, in particular of the inner ring 2, on which the roller set is held by the cage 7, can be designed with a groove-shaped contour and / or be laterally enclosed by guide projections 15, 16, whereby the raceway 5 can also be groove-shaped depending on the contour of the rolling elements 11. Due to the groove-shaped contour or the lateral enclosure by guide projections 15, 16, the rolling elements 11 cannot slip laterally off the bearing ring 2 in the preassembled state according to Fig. 2. Alternatively or additionally, a guide contour could also be provided on one or both cage rings 8, 9 to prevent the inner ring 2 and / or the outer ring 3 from slipping out axially.

[0046] As Fig. 5 shows, the cage 7 can define a conical envelope contour as a whole, wherein a conical envelope contour can be applied to the cage 7 on both the inner shell surface side and the outer shell surface side.

[0047] As can be seen from the drawings, the rolling bearing 1 is characterized by the following aspects: Firstly, it is provided that the separating webs 10 are arranged eccentrically offset relative to the central axis 14 of the bearing gap 13 and / or relative to the axes of rotation 12 of the rolling elements 11 towards one of the raceways 6.

[0048] It can be provided that the distance of the separating webs 10 from the raceway 5 of the inner ring 2 is at least 150% or at least 200% of the distance of the separating webs 10 from the raceway 6 of the outer ring 3.

[0049] In particular, the separating webs 10 can be arranged approximately at 2 / 3 to 3 / 4 of the clear height H of the bearing gap 13 between the two raceways 5, 6.

[0050] Furthermore, it can be provided that the rolling elements 11 are held by the cage 7 with the separating webs 10 on one of the bearing rings 2, so that the said bearing ring 2, the rolling elements 11 and the cage 7 with the separating webs 10 form a pre-assembled assembly.

[0051] Furthermore, it can be provided that the raceway 5 of the bearing ring 2, on which the rolling elements 11 are held by the cage 7 with the separating webs 10 in a pre-assembled manner, is groove-shaped and / or is laterally enclosed by guide projections 15, 16.

[0052] Furthermore, it can be provided that the two tracks 5, 6 have different track diameters and the separating webs 10 are arranged at a greater distance from the track 5 with the smaller track diameter than from the track 6 with the larger track diameter.

[0053] Furthermore, it can be provided that one of the bearing rings 2 forms an inner ring and the other bearing ring 3 forms an outer ring, wherein the separating webs 10 are spaced further from the raceway 5 of the inner ring 2 than from the raceway 6 of the outer ring 3 and hold the rolling elements 11 on said inner ring. Furthermore, it can be provided that the cage 7 has at least one cage ring 8, 9 to which the separating webs 10 are attached, wherein a mountable joint separation point is provided between the cage ring 8, 9 and the separating webs 10.

[0054] Furthermore, it can be provided that a detachable fastening or a plug-in connection is provided between the cage ring 8, 9 and the separating webs 10.

[0055] Furthermore, it can be provided that the separating webs 10 have a circular cross-section.

[0056] Furthermore, it can be provided that the separating webs 10 have a cross-section that deviates from the circular shape, in particular a trapezoidal, triangular or polygonal cross-section.

[0057] Furthermore, it can be provided that the separating webs 10 have a substantially constant diameter or a substantially constant thickness over their length.

[0058] Furthermore, it can be provided that the separating webs 10 have a variable diameter over their length, in particular continuously becoming thicker towards one end side.

[0059] Furthermore, it can be provided that the rolling elements 11 are tapered rollers and / or the rolling bearing is designed as a single-row tapered roller bearing.

[0060] Furthermore, it can be provided that the cage 7 with its separating webs 10 defines a conical envelope contour.

Claims

Claims 1. Rolling bearing, preferably a centerless large-diameter rolling bearing, with two concentric bearings (2, 3) which can be rotated relative to one another, at least one row (4) of rolling elements (11) which support the bearing rings (2, 3) against one another and roll on raceways (5, 6) of the bearing rings (2, 3), and a cage (7) with separating webs (10) between the rolling elements (11) for separating and guiding the rolling elements (11), characterized in that the separating webs (10) are arranged eccentrically offset towards one of the raceways (6) with respect to a bearing gap center axis (14), along which the rolling elements (11) are arranged with their axes of rotation distributed relative to one another.

2. Rolling bearing according to the preceding claim, wherein the distance of the separating webs (10) from one of the raceways (5) is at least 150% or at least 200% of the distance of the separating webs (10) from the other raceway (6).

3. Rolling bearing according to one of the preceding claims, wherein the separating webs (10) are arranged approximately at 2 / 3 to 3 / 4 of the clear height (H) of the bearing gap (13) between the two raceways (5, 6).

4. Rolling bearing according to one of the preceding claims, wherein the rolling elements (11) are held by the cage (7) with the separating webs (10) on one of the bearing rings (2), so that said bearing ring (2), the rolling elements (11) and the cage (7) with the separating webs (10) form a pre-assembled assembly.

5. Rolling bearing according to the preceding claim, wherein the raceway (5) of the bearing ring (2), on which the rolling elements (11) are held in a pre-assembled manner by the cage (7) with the separating webs (10), is groove-shaped and / or is laterally enclosed by guide projections (15, 16).

6. Rolling bearing according to one of the preceding claims, wherein the two raceways (5, 6) have different raceway diameters and the separating webs (10) are arranged at a greater distance from the raceway (5) with the smaller raceway diameter than from the raceway (6) with the larger raceway diameter.

7. Rolling bearing according to one of the preceding claims, wherein one of the bearing rings (2) forms an inner ring and the other bearing (3) forms an outer ring, wherein the separating webs (10) are spaced further from the raceway (5) of the inner ring (2) than from the raceway (6) of the outer ring (3) and hold the rolling elements (11) on said inner ring.

8. Rolling bearing according to one of the preceding claims, wherein the cage (7) has at least one cage ring (8, 9) to which the separating webs (10) are fastened, wherein a mountable joining separation point is provided between the cage ring (8, 9) and the separating webs (10).

9. Rolling bearing according to the preceding claim, wherein a detachable fastening or a plug-in connection is provided between the cage ring (8, 9) and the separating webs (10).

10. Rolling bearing according to one of the preceding claims, wherein the separating webs (10) have a circular cross-section.

11. Rolling bearing according to one of claims 1-9, wherein the separating webs (10) have a cross-section deviating from the circular shape, in particular trapezoidal, triangular or polygonal.

12. Rolling bearing according to one of the preceding claims, wherein the separating webs (10) have a substantially constant diameter or thickness over their length.

13. Rolling bearing according to one of claims 1-11, wherein the separating webs (10) have a variable diameter over their length, in particular continuously becoming thicker towards one end face.

14. Rolling bearing according to one of the preceding claims, wherein the rolling elements (11 ) Tapered rollers and / or the rolling bearing is designed as a single-row tapered roller bearing.

15. Rolling bearing according to one of the preceding claims, wherein the cage (7) with its separating webs (10) defines a conical envelope contour.

Images