Plain bearings with sliding segments

Abstract

Plain bearings with a first bearing component and a second bearing component that are arranged to rotate relative to each other in one direction of rotation around an axis of rotation, wherein at least two sliding segments (1) are arranged between the first bearing component and the second bearing component, wherein the at least two sliding segments (1) each have a support structure (2) for fixing the sliding segment (1) to the first or second bearing component and a sliding surface (3) for sliding contact of the sliding segment (1) to the second or first bearing component, wherein the sliding surface (3) has a leading leading edge (4) and a trailing trailing edge (5) in the direction of rotation, wherein the sliding surface (3) has an oil distribution groove (6) which is arranged directly adjacent to the front leading edge (4), and wherein the sliding segment (1) has a through-opening (7) for an oil supply to the oil distribution groove (6), characterized in that the through-opening (7) for the oil supply to the oil distribution groove (6) extends from a radial outer surface (21) of the support structure (2) to the oil distribution groove (6) or the sliding surface (3).

Description

[0001] The invention relates to a sliding bearing with a first bearing component and a second bearing component which are arranged to rotate relative to each other in a direction of rotation about an axis of rotation, in which at least two sliding segments are arranged between the first bearing component and the second bearing component.

[0002] Axial bearings typically employ sliding elements that are supplied with lubricant from the rear via a circumferential gap. This lubricant supply can vary around the segment's circumference, which is usually circular, and is neither precisely calculable nor adjustable, as the gap geometry is influenced by various factors such as manufacturing tolerances, the operating condition, and the segments' own weight. This results in high oil loss with conventional oil supply systems, as a large portion of the oil flows down the sides of the segments without providing any technical benefit.

[0003] In particular, the inherent inclination of a wind turbine's drive train, typically 5°–6° from the horizontal, does not guarantee that the oil will reach the guide wheel; in other words, the sliding surface would not be wetted at all. Insufficient lubrication and increased wear are the resulting consequences.

[0004] Hydrostatic lifting is generally achieved via a pocket or annular groove. This annular groove has a diameter of approximately 50%–60% of the segment diameter. A larger diameter would negatively affect the hydrodynamic pressure distribution and thus limit the segment's load-bearing capacity. With these dimensions, the required hydrostatic lifting pressures increase to over 200 bar, which should be avoided. Reference is also made to DE 10 2013 211 710 C5, DE 24 09 711 C2, DE 699 26 046 T2, US 2014 / 0 345 141 A1, and US 2015 / 0 043 849 A1.

[0005] It is therefore an object of the present invention to provide plain bearings with sliding segments arranged between a first bearing component and a second bearing component, in which the lubrication between the bearing components and the sliding segments is optimized.

[0006] This problem is solved by the combination of features according to claim 1.

[0007] According to the invention, a sliding bearing is proposed comprising a first bearing component and a second bearing component, which are arranged to rotate relative to each other in a direction of rotation about an axis of rotation. At least two sliding segments are arranged between the first and second bearing components. Each of the at least two sliding segments has a support structure for fixing the sliding segment to the first and second bearing components, respectively, and a sliding surface for sliding contact between the sliding segment and the second and first bearing components, respectively. Furthermore, the sliding surface has a leading edge and a trailing edge in the direction of rotation and encompasses an oil distribution groove, which is arranged directly adjacent to the leading edge.Furthermore, the sliding segment has a through-opening for an oil supply to the oil distribution groove, which, according to the invention, extends from a radial outer surface of the support structure to the oil distribution groove or the sliding surface.

[0008] The advantage of this method is that direct lubrication of the sliding element with lubricant from the sliding bearing ensures and optimizes lubricated operation. The amount of lubricant supplied is crucial for the service life of the sliding element. This service life can be precisely designed, calculated, influenced, and increased through the use of direct lubrication. The lubricant is supplied directly to the required location, specifically the sliding surface of the sliding segment, through the segment itself. The supply is fed directly at the segment and the flow rate can be adjusted to the actual demand at the lubrication gap. This enables targeted oil supply even at low circumferential speeds and in geometrically challenging configurations, such as an inverted arrangement. Furthermore, individual oil supply to each segment is possible.By eliminating the otherwise required liner ring, the sliding segments can be made larger, thus achieving a higher load-bearing capacity of the bearing. Furthermore, in another advantageous embodiment, the through-hole for the oil supply of the oil distribution groove can be connected directly or indirectly to a high-pressure oil supply to achieve hydrostatic lifting.

[0009] In an advantageous embodiment, the sliding surface of the sliding segment is essentially circular. This is beneficial for lubricant distribution and the arrangement and design of the oil distribution groove at the leading edge.

[0010] Preferably, the plain bearing is designed such that the oil distribution groove of the sliding surface is arc-shaped, preferably spanning an angle of 90° to 180°. Due to the arc-shaped form of the oil distribution groove, it is optimally adapted to the leading edge, thereby improving the lubrication of the sliding surface or sliding segment. Furthermore, a crescent-shaped oil distribution groove is also advantageous for various applications of the plain bearing, the diameter of which is larger in a central region than at both ends of the oil distribution groove.

[0011] In one embodiment of the invention, the sliding surface is provided to have a further oil distribution groove, which is arranged directly adjacent to the rear exit edge. This further improves the lubricant distribution on the sliding surface of the sliding segment.

[0012] Furthermore, an embodiment is advantageous in which the additional oil distribution groove of the sliding surface is arc-shaped, preferably spanning an angle of 90° to 180°. Corresponding to the oil distribution groove, the arc-shaped additional oil distribution groove optimizes the lubrication of the sliding surface or sliding segment. A crescent-shaped oil distribution groove is also possible.

[0013] In a further advantageous embodiment, the invention provides that a groove gap is formed at the edge of the sliding surface between the oil distribution groove and the subsequent oil distribution groove. Due to the interrupted groove, two, three, or four circular segment-shaped grooves are formed, depending on the number of grooves. This results in a load-bearing pressure distribution between the grooves towards the center of the segment, leading to hydrostatic lifting. The load-bearing pressure loss is negligibly small compared to a closed annular hydrostatic groove.

[0014] The sliding bearing according to the invention is designed in one embodiment such that the oil distribution groove and the further oil distribution groove are connected by means of an oil circuit. It is advantageous that, when both grooves are supplied with high-pressure oil, an integrated hydrostatic lifting mechanism is implemented.

[0015] In an alternative embodiment of the present plain bearing, the oil distribution groove of the sliding surface is further provided to extend fully along the entire edge of the sliding surface. This ensures a very good supply of lubricant to the entire sliding surface of the sliding segment.

[0016] In a further alternative embodiment of the invention, the oil distribution groove of the sliding surface is formed by a plurality of recesses, preferably by a plurality of bores. The recesses of the oil distribution groove are arranged in an arc shape and preferably spaced apart from one another in a row. It is advantageous that the lubricant can be applied to the sliding surface via the respective recess, thus ensuring a uniform lubricant distribution or adapting it to the specific application by means of an arrangement or number of recesses.

[0017] In an advantageous embodiment, each recess has a through-opening for supplying oil to the oil distribution groove, extending from a radial outer surface of the support structure to the oil distribution groove or the sliding surface. This ensures that the oil distribution groove or the sliding surface is supplied with lubricant.

[0018] In a further advantageous embodiment, the invention provides that a channel is formed on the radial outer surface of the support structure for rinsing the support structure with oil or for supplying oil to the oil distribution groove. The advantage of this is that the oil, which rinses the sliding segment at its outer surface, reaches the sliding surface via the recesses and can be distributed on the sliding surface of the sliding segment according to the arrangement and number of recesses.

[0019] Another alternative embodiment of the present plain bearing features a rectangular or square sliding surface and a straight oil distribution groove on the sliding surface. Such a plain bearing or oil distribution groove improves lubrication between the bearing components and the sliding segments in some applications.

[0020] In a preferred embodiment of the invention, an anti-rotation device, in particular a bolt-shaped anti-rotation device, is formed on an outer surface of the support structure. In this way, rotation of the sliding segment during operation is prevented by a correspondingly designed counterpart of the sliding bearing.

[0021] The sliding bearing according to the invention is designed in one embodiment as an axial bearing, in particular an axial bearing for a drive train of a wind turbine.

[0022] Other advantageous embodiments of the invention are characterized in the dependent claims or are described in more detail below together with the description of the preferred embodiment of the invention with reference to the figures. The figures show: Fig. 1. A perspective view of a sliding segment of a plain bearing with an arc-shaped oil distribution groove. Fig. 2 a perspective view of a sliding segment of a sliding bearing with two arc-shaped oil distribution grooves, Fig. 3 a perspective view of a sliding segment of a plain bearing with an annular oil distribution groove and Fig. 4 a perspective view of a sliding segment of a sliding bearing with an oil distribution groove formed by recesses.

[0023] In Fig. Figure 1 shows a perspective view of a sliding segment 1 of a sliding bearing with an arc-shaped oil distribution groove 6. The sliding bearing is designed as an axial bearing for a drive train of a wind turbine. The sliding bearing comprises a plurality of sliding segments 1, and the individual sliding segments 1 are arranged on a common pitch circle and together form the axial bearing.

[0024] The sliding bearing comprises a first bearing component and a second bearing component, which are arranged to rotate relative to each other in one direction of rotation around an axis of rotation. The plurality of sliding segments 1 are arranged between the first bearing component and the second bearing component.

[0025] Each sliding segment 1 of the multitude of sliding segments 1 has a support structure 2 for fixing the sliding segment 1 to the first or second bearing component and a sliding surface 3 for sliding contact of the sliding segment 1 to the second or first bearing component.

[0026] The sliding surface 3 of the sliding segment 1 is essentially round and has a front leading edge 4 and a rear trailing edge 5 in the direction of rotation.

[0027] Furthermore, the sliding surface 3 has an oil distribution groove 6, which is arranged directly adjacent to the leading edge 4. The oil distribution groove 6 of the sliding surface 3 is also arc-shaped and spans an angle of approximately 90°.

[0028] The sliding segment 1 has a through-opening 7 for supplying oil to the oil distribution groove 6, which extends from a radial outer surface 21 of the support structure 2 to the oil distribution groove 6 or the sliding surface 3. Furthermore, a channel 22 is formed on the radial outer surface 21 of the support structure 2 for rinsing the support structure 2 with oil or for supplying oil to the oil distribution groove 6. In addition, a bolt-shaped anti-rotation device 8 is formed on the radial outer surface 21 of the support structure 2.

[0029] Since the sliding segments in the following section of the figure description essentially have the same characteristics, only the fundamental differences will be discussed below.

[0030] Fig. Figure 2 shows a perspective view of a sliding segment 1 of a sliding bearing with two arc-shaped oil distribution grooves 6, 13. The sliding surface 3 of the sliding segment 1 has a further oil distribution groove 13, which is arranged directly adjacent to the rear exit edge 5. The further oil distribution groove 13 of the sliding surface 3 is crescent-shaped and spans an angle of 90°.

[0031] A groove gap 10 is formed at the edge of the sliding surface 3 between the oil distribution groove 6 and the further oil distribution groove 13. Furthermore, the oil distribution groove 6 and the further oil distribution groove 13 are connected by means of an oil circuit.

[0032] In Fig. Figure 3 shows a perspective view of a sliding segment 1 of a sliding bearing with an annular oil distribution groove 6 that extends fully along the entire edge of the sliding surface 3. Furthermore, the sliding segment 1 includes a through-opening 7 for supplying oil to the oil distribution groove 6, which extends from a radial outer surface 21 of the support structure 2 to the oil distribution groove 6 or the sliding surface 3.

[0033] Furthermore, in Fig. Figure 4 shows a perspective view of a sliding segment 1 of a sliding bearing with an oil distribution groove 6 formed by recesses 11. The oil distribution groove 6 of the sliding surface 3 is formed by a plurality of recesses 11, in particular by a plurality of bores. Furthermore, the recesses 11 of the oil distribution groove 6 are arranged in an arc and spaced apart from one another in a row.

[0034] Furthermore, the recesses 11 each have a through-opening 7 for an oil supply to the oil distribution groove 6, which extends from a radial outer surface 21 of the support structure 2 to the oil distribution groove 6 or the sliding surface 3.

[0035] The invention is not limited in its implementation to the preferred embodiments specified above. Rather, a number of variants are conceivable which make use of the solution presented even in fundamentally different designs.

Claims

[1] Plain bearings comprising a first bearing component and a second bearing component arranged to rotate relative to each other in a direction of rotation about an axis of rotation, wherein at least two sliding segments (1) are arranged between the first bearing component and the second bearing component, wherein the at least two sliding segments (1) each have a support structure (2) for fixing the sliding segment (1) to the first or second bearing component and a sliding surface (3) for sliding contact of the sliding segment (1) to the second or first bearing component, wherein the sliding surface (3) has a leading leading edge (4) and a trailing trailing edge (5) in the direction of rotation, wherein the sliding surface (3) has an oil distribution groove (6) which is arranged directly adjacent to the front leading edge (4), and wherein the sliding segment (1) has a through-opening (7) for an oil supply to the oil distribution groove (6), characterized by , that the passage opening (7) for the oil supply of the oil distribution groove (6) extends from a radial outer surface (21) of the supporting structure (2) to the oil distribution groove (6) or the sliding surface (3). [2] Plain bearings according to claim 1, characterized by , that the sliding surface (3) of the sliding segment (1) is essentially round. [3] Plain bearings according to one of claims 1 to 2, characterized by , that the oil distribution groove (6) of the sliding surface (3) is arc-shaped, wherein the oil distribution groove (6) preferably spans an angle of 90° to 180°. [4] Plain bearings according to one of the preceding claims, characterized by , that the sliding surface (3) has a further oil distribution groove (13) which is arranged directly adjacent to the rear exit edge (5). [5] Plain bearings according to claim 4, characterized by, that the further oil distribution groove (13) of the sliding surface (3) is arc-shaped, wherein the further oil distribution groove (13) preferably spans an angle of 90° to 180°. [6] Plain bearings according to one of claims 4 or 5, characterized by , that a groove gap (10) is formed at the edge of the sliding surface (3) between the oil distribution groove (6) and the further oil distribution groove (13). [7] Plain bearings according to the preceding claim, characterized by , that the oil distribution groove (6) and the further oil distribution groove (13) are connected by means of an oil circuit. [8] Plain bearings according to one of claims 1 to 2, characterized by , that the oil distribution groove (6) of the sliding surface (3) is fully formed along the entire edge of the sliding surface (3). [9] Plain bearings according to any one of claims 1 to 2, characterized by, that the oil distribution groove (6) of the sliding surface (3) is formed by a plurality of recesses (11), preferably by a plurality of bores, wherein the recesses (11) of the oil distribution groove (6) are arranged in an arc shape and are preferably spaced apart from one another in a row. [10] Plain bearings according to the preceding claim, characterized by , that the recesses (11) each have a through-opening (7) for an oil supply to the oil distribution groove (6), which extends from a radial outer surface (21) of the supporting structure (2) to the oil distribution groove (6) or the sliding surface (3). [11] Plain bearings according to any one of the preceding claims, characterized by , that a channel (22) is formed on the radial outer surface (21) of the support structure (2) for flushing the support structure (2) with oil or for supplying oil to the oil distribution groove (6). [12] Plain bearings according to claim 1, characterized by, that the sliding surface (3) is rectangular or square and the oil distribution groove (6) of the sliding surface (3) is straight. [13] Plain bearings according to claim 1, characterized by , that the sliding surface (3) is annular or annular segment-shaped and the oil distribution groove (6) of the sliding surface (3) is straight and / or arc-shaped. [14] Plain bearings according to one of the preceding claims, characterized by , that an anti-rotation device (8) is formed on the radial outer surface (21) of the supporting structure (2), in particular a bolt-shaped anti-rotation device (8). [15] Plain bearings according to any one of the preceding claims, characterized by , that the sliding bearing is designed as an axial bearing, in particular an axial bearing for a drive train of a wind turbine.

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