Plain bearing arrangement, nacelle equipped with the plain bearing arrangement for a wind power plant, and wind power plant

Abstract

Proposed is a plain bearing arrangement (9) comprising: - an inner ring element (13); - an outer ring element (14); - at least one plain bearing element (15) that is arranged between the inner ring element (13) and the outer ring element (14), wherein the outer ring element (14) and the inner ring element (13) are mounted rotatably relative to one another about an axis of rotation (16) by means of the plain bearing element (15), wherein the plain bearing element (15) comprises multiple plain bearing pads (22), wherein the individual plain bearing pads (22) each have a domed bearing surface (27). The domed bearing surface (27) has a first radius (34) in a longitudinal section along the axis of rotation (16) and has a second radius (35) in a cross section normal to the axis of rotation (16). In particular, the second radius (35) is greater than the first radius (34).

Description

[0001] SLIDE BEARING, AS WELL AS A NACELLE EQUIPPED WITH THE SLIDE BEARING FOR A WIND TURBINE, AS WELL AS A WIND TURBINE

[0002] The invention relates to a plain bearing, as well as a nacelle equipped with the plain bearing for a wind turbine, as well as a wind turbine.

[0003] DE 650737 C discloses a plain bearing with an inner ring element and an outer ring element, with several plain bearing pads arranged on the inner ring element. The plain bearing pads have a sliding surface in the form of a spherical cap, which interacts with a corresponding sliding surface on the outer ring element. Such spherical bearings are used to absorb both a radial force and an axial force between an inner ring element and an outer ring element.

[0004] Spherical bearings according to DE 650737 C must have a certain width for a given axial load capacity so that a certain projected axial area is achieved. Since the radial load capacity of spherical bearings also depends on the width, an unnecessarily high radial load capacity is often achieved. This leads to spherical bearings often being oversized with regard to their radial load capacity and thus resulting in high weight.

[0005] The object of the present invention was to provide an improved plain bearing. In particular, the object of the present invention was to provide a plain bearing that has the smallest possible plain bearing pad width for a given diameter, while simultaneously adapting the radial and axial load-bearing capacity to the given load profile.

[0006] This object is achieved by a device according to the claims.

[0007] According to the invention, a plain bearing is provided. The plain bearing comprises:

[0008] - an inner ring element;

[0009] - an outer ring element;

[0010] - at least one plain bearing element which is arranged between the inner ring element and the outer ring element, wherein the outer ring element and the inner ring element are mounted rotatably relative to one another about a rotation axis by means of the plain bearing element, wherein the plain bearing element comprises a plurality of plain bearing pads, wherein the individual plain bearing pads each have a curved bearing surface.

[0011] The curved bearing surface has a first radius in a longitudinal section along the rotation axis and a second radius in a cross-section perpendicular to the rotation axis. In particular, it can be provided that the second radius is larger than the first radius.

[0012] The plain bearing according to the invention has the surprising advantage that, thanks to the different radii, the axial load-bearing capacity and the radial load-bearing capacity of the plain bearing can be coordinated for a given diameter of the inner ring element. This allows the weight of the individual plain bearing pads to be reduced. Furthermore, the efficiency of the plain bearing can be improved by optimizing the axial and radial load-bearing capacity of the plain bearing.

[0013] A counter surface can be formed corresponding to the bearing surface. The bearing surface and the counter surface can together form a plain bearing pair.

[0014] A longitudinal section along the rotational axis has a cutting line that extends in the axial direction of the plain bearing. The rotational axis lies in the cutting plane of the cutting line. In other words, the cutting plane of the longitudinal section is exactly centered and thus located in the rotational axis of the plain bearing.

[0015] The axial position of the cross-section normal to the rotation axis is chosen at the position of the axial vertex of the bearing surface.

[0016] In particular, it can be provided that the first radius extends in the axial direction and that the second radius extends in the circumferential direction. Furthermore, it can be provided that the first radius has a constant value over the entire axial extent of the bearing surface. The first radius can have a center point that is radially spaced from the axis of rotation.

[0017] Furthermore, it can be expedient if the bearing surface of the plain bearing pads is each designed as a torus segment of a torus with a circular cross-section. A bearing surface in the shape of a torus segment, in particular, can be manufactured with sufficiently high precision. Furthermore, this bearing surface shape can exhibit good functionality. A torus segment can be formed by arranging a circular cross-section with the first radius at a distance from the rotation axis and rotating it about the rotation axis. The distance from the rotation axis can be selected such that an axial vertex, i.e. the radially outermost point, is arranged at a distance of the second radius from the rotation axis.

[0018] Furthermore, the first radius can be between 5% and 99%, in particular between 10% and 50%, preferably between 15% and 30% of the second radius. This has the advantage that this measure allows for a particularly good distribution between radial load-bearing capacity and axial load-bearing capacity.

[0019] Furthermore, it may be provided that the second radius is measured at an axial vertex.

[0020] Another advantageous embodiment is one in which the plain bearing pads, starting from the axial apex, have a first axial extension in a first axial direction and a second axial extension in a second axial direction, wherein the first axial extension is greater than the second axial extension. This has the advantage that, thanks to this measure, the plain bearing pad, while being as small as possible, has a good ability to absorb axial forces directed in a main load direction. In the axial secondary load direction, lower axial forces can be absorbed depending on the requirements. By varying the values ​​of the first axial extension and the second axial extension, the plain bearing can be specifically adapted to the requirements.

[0021] According to a further development, it is possible for the second axial extension to be between 5% and 99%, in particular between 20% and 95%, preferably between 50% and 80% of the first axial extension. This has the advantage that this measure gives the plain bearing pad a good ability to absorb axial forces directed in a main load direction while being as small as possible. In the axial secondary load direction, lower axial forces can be absorbed according to requirements, whereby the overall structural extension of the plain bearing is kept as small as possible. In an alternative embodiment, it can be provided that the plain bearing pads, starting from the axial apex, have a first axial extension in a first axial direction and a second axial extension in a second axial direction, wherein the first axial extension is the same size as the second axial extension.A plain bearing pad designed in this way can have the simplest possible structure. Furthermore, such a plain bearing pad can be subjected to equal loads in both axial directions.

[0022] According to an advantageous development, the plain bearing pads can have a plain bearing pad width, wherein the plain bearing pad width is between 20% and 170%, in particular between 60% and 140%, preferably between 90% and 120% of the first radius. Plain bearing pads with such a ratio of plain bearing pad width to first radius exhibit surprisingly low wear.

[0023] In a further embodiment, it can be provided that the second radius has a value different from the first radius, wherein the first radius has a constant value over the entire axial extent of the bearing surface. In other words, the first radius can have a constant radius over the entire axial extent of the bearing surface, wherein the resulting surface is not a spherical cap. The resulting bearing surface deviates from the shape of a spherical cap if the second radius is larger than the first radius or the second radius is smaller than the first radius. For the sake of simplicity, a person skilled in the art would choose the first radius and the second radius to be the same size in order to be able to manufacture the bearing surface as easily as possible. In this case, the bearing surface would have the shape of a spherical cap.The measure according to the invention makes it possible to easily manufacture the bearing surface due to the constant value across the entire axial extent, while simultaneously adjusting the ratio of radial load-bearing capacity to axial load-bearing capacity by varying the value of the second radius from the first radius. This allows the plain bearing element to have the smallest possible overall width, which is selected so that the radial load-bearing capacity can be achieved at a given second radius. The axial load-bearing capacity can be adjusted by adjusting the first radius.

[0024] Thus, in a first embodiment, the second radius can be larger than the first radius. This allows for a high axial load-bearing capacity to be achieved with a given radial load-bearing capacity. In a further embodiment, the second radius can be smaller than the first radius. Such a design can be advantageous if only low demands are placed on the axial load-bearing capacity for a given radial load-bearing capacity.

[0025] According to the invention, a nacelle for a wind turbine is provided, the nacelle comprising:

[0026] - a nacelle housing;

[0027] - a rotor hub;

[0028] - a rotor bearing for supporting the rotor hub on the nacelle casing. The rotor bearing comprises a plain bearing according to one of the above types.

[0029] Particularly in gondolas according to the invention, the sliding bearing according to the invention leads to easy maintenance of the sliding bearing.

[0030] Furthermore, it can be provided that the plain bearing pads of the plain bearing have, starting from the axial apex, a first axial extension in a first axial direction and a second axial extension in a second axial direction, wherein the first axial extension is greater than the second axial extension, wherein the plain bearing pads are accommodated in the nacelle housing such that the first axial extension is formed on a side of the axial apex facing away from the rotor hub. This has the advantage that this measure allows the increased axial force on the plain bearing pads to be absorbed particularly well. The increased axial force on the plain bearing pads arises due to the wind force acting on the rotor hub.

[0031] According to a particular embodiment, it is possible to form a first rotor shaft bearing and a second rotor shaft bearing, wherein the first rotor shaft bearing is arranged closer to the rotor hub than the second rotor shaft bearing, wherein the second rotor shaft bearing is designed as a plain bearing according to the above embodiments. Such a structure has a surprisingly simple design, wherein the forces occurring in the rotor shaft can be well absorbed by the described design.

[0032] According to an advantageous further development, it can be provided that the plain bearing pads are fastened to a rotor shaft.

[0033] Furthermore, it may be expedient for the individual plain bearing pads to each have a fastening profile opposite the bearing surface. In particular, the inner ring element may have at least one receptacle on its radial outer side, which serves to positively connect the plain bearing pads to the inner ring element. This measure allows for easy replacement of the plain bearing pads and, at the same time, ensures a secure fit of the plain bearing pads when the plain bearing is in the operational state.

[0034] According to a special design, it is possible to have an axial stop for the plain bearing pad on the inner ring element in the area of ​​the mount. This offers the advantage that the plain bearing pad can be positioned precisely in the axial direction.

[0035] According to an advantageous development, a fastening element can be provided by means of which the plain bearing pad is pressed against the axial stop in the axial direction. This has the advantage that the plain bearing pad can be fixed or correctly positioned in the axial direction in order to achieve the functionality of the plain bearing.

[0036] Furthermore, at least one anti-rotation element can be provided, which acts between the axial stop ring and at least one of the plain bearing pads. This measure can ensure that at least one of the plain bearing pads is secured against rotation relative to a shaft.

[0037] Furthermore, it can be provided that the axial stop is formed on a stop ring that is mounted on a shaft. In particular, it can be provided that the axial stop ring is shrunk onto the shaft.

[0038] In an alternative embodiment, the axial stop can be formed directly on the shaft. Furthermore, a positioning boss can be formed on the plain bearing pad, which corresponds to the axial stop.

[0039] In an alternative design, the plain bearing pads can be attached to the nacelle housing. This can be done directly or with the interposition of a bearing bracket.

[0040] In such a design, the bearing surface can be formed on an inner side of the plain bearing pads. A counter surface for the bearing surface can be formed on the inner ring element. In particular, it can be provided that the counter surface is formed directly on the shaft, with the shaft forming the inner ring element. In an alternative design variant, it can also be provided that the counter surface is arranged on a structurally independently formed inner ring element, with the inner ring element being coupled to the shaft. In particular, it can be provided that the inner ring element is shrunk onto the shaft.

[0041] In particular, it can be provided that the outer ring element has at least one receptacle on its radial inner side, which serves to positively connect the plain bearing pads to the outer ring element. This measure allows for easy replacement of the plain bearing pad and, at the same time, ensures a tight fit of the plain bearing pads when the plain bearing is in the operational state.

[0042] According to a special design, it is possible to have an axial stop for the plain bearing pad on the outer ring element in the area of ​​the mount. This offers the advantage that the plain bearing pad can be positioned precisely in the axial direction.

[0043] According to an advantageous development, a fastening element can be provided by means of which the plain bearing pad is pressed axially against the axial stop on the outer ring element. This has the advantage that the plain bearing pad can be fixed or correctly positioned in the axial direction in order to achieve the functionality of the plain bearing.

[0044] The invention further relates to a wind turbine with a nacelle, the nacelle comprising:

[0045] - a nacelle housing;

[0046] - a rotor hub with rotor blades arranged on it;

[0047] - a rotor bearing for supporting the rotor hub on the nacelle casing. The rotor bearing comprises a plain bearing according to one of the above types.

[0048] According to a particular embodiment, it is possible for the rotor bearing to comprise a bearing support in which the outer ring element is accommodated. In an alternative embodiment, the bearing support can be designed directly as an outer ring element.

[0049] The bearing bracket can be attached to the nacelle housing.

[0050] In an alternative design variant, it is also conceivable for the bearing support to be formed directly in the nacelle housing. Thus, the outer ring element can also be formed directly in the nacelle housing.

[0051] According to a further development, it is possible for a removal opening to be formed in the outer ring element, which, starting from a first end face of the outer ring element, interrupts the counter surface of the outer ring element. This has the advantage that this measure makes it easy to replace the individual plain bearing pads without having to disassemble the entire plain bearing into its individual parts. In particular, it is conceivable that this measure makes it possible to replace the individual plain bearing pads while the plain bearing is installed, without having to completely disassemble it. Furthermore, it can be provided that the removal opening extends from a first end face of the outer ring element at least to the apex of the plain bearing element.

[0052] Furthermore, it is conceivable that a porous material, such as a sponge, is placed in the removal opening during the operating state of the plain bearing to temporarily absorb lubricating oil. This measure can ensure that the sliding surface of the individual plain bearing pads is evenly covered with a film of lubricating oil.

[0053] The individual plain bearing pads can be easily removed from their operating position through the removal opening.

[0054] Furthermore, the removal opening can be designed to widen radially toward the first end face. This offers the advantage that the outer ring element can have the highest possible stability while simultaneously allowing the plain bearing pad to be removed as easily as possible through the removal opening.

[0055] Furthermore, it can be provided that a plain bearing pad retaining ring is formed, which serves to secure the plain bearing pads, wherein the plain bearing pad retaining ring is received on the inner ring element. This has the advantage that this measure allows the plain bearing pads to be firmly coupled to the inner ring element.

[0056] In addition, the plain bearing pad retaining ring can be shrunk onto the inner ring element. This represents an extremely durable and practical connection, especially for rotor shafts. During the shrink-fitting process, the plain bearing pad retaining ring is heated and / or the inner ring element is cooled to facilitate axial pressing. After temperature equalization and thus compensation of thermal expansion, a tight fit of the plain bearing pad retaining ring on the inner ring element can be achieved.

[0057] In an alternative embodiment or additionally, it can be provided that the plain bearing pad receiving ring is coupled to the inner ring element by means of a material connection, such as a welded connection.

[0058] In yet another embodiment variant, it can be provided that the plain bearing pad receiving ring is coupled to the inner ring element by means of a positive connection, such as a screw connection.

[0059] Furthermore, it can be provided that a plurality of threaded holes are formed in the plain bearing pad retaining ring, which are arranged in the axial direction of the plain bearing pad retaining ring and serve to accommodate fastening screws. Through holes are formed in the plain bearing pads through which the fastening screws are inserted in order to clamp the plain bearing pads to the plain bearing pad retaining ring using the fastening screws. Such a connection between the plain bearing pads and the plain bearing pad retaining ring is easy to establish.

[0060] In a further development, the plain bearing pads can have a shoulder on their inner side, which rests against one end face of the plain bearing pad retaining ring, with the through holes located in the area of ​​the shoulder. This measure achieves a sufficiently resilient connection between the plain bearing pads and the inner ring.

[0061] In a first embodiment, the plain bearing may be designed as a hydrodynamic bearing. In a further embodiment, the plain bearing may be designed as a hydrostatic bearing.

[0062] In yet another embodiment, the plain bearing can be designed as a self-lubricating bearing.

[0063] For a better understanding of the invention, it is explained in more detail using the following figures.

[0064] They show in a highly simplified, schematic representation:

[0065] Fig. 1 is a schematic representation of a wind turbine;

[0066] Fig. 2 is a longitudinal sectional view of a first embodiment of a plain bearing;

[0067] Fig. 3 a perspective view of the plain bearing;

[0068] Fig. 4 is a perspective view of a plain bearing pad;

[0069] Fig. 5 is a cross-sectional view along section line VV of Fig. 2;

[0070] Fig. 6 a perspective view of a torus with a drawn sliding surface;

[0071] Fig. 7 a detailed view of the longitudinal section from Fig. 2;

[0072] Fig. 8 is a longitudinal sectional view of a second embodiment of a plain bearing;

[0073] Fig. 9 is a longitudinal sectional view of a third embodiment of a plain bearing.

[0074] By way of introduction, it should be noted that in the variously described embodiments, identical parts are provided with identical reference symbols or component designations. The disclosures contained throughout the description can be applied analogously to identical parts with identical reference symbols or component designations. Furthermore, the positional information chosen in the description, such as top, bottom, side, etc., refers to the directly described and illustrated figure, and these positional information must be applied analogously to the new position in the event of a change in position.

[0075] Fig. 1 shows a schematic representation of a first embodiment of a wind turbine 1 for generating electrical energy from wind power. The wind turbine

[0076] 1 comprises a nacelle 2, which is rotatably mounted on a tower 3. The nacelle 2 comprises a nacelle housing 4, which forms the main structure of the nacelle 2. The electrical components, such as a generator of the wind turbine 1, are arranged in the nacelle housing 4 of the nacelle 2.

[0077] Furthermore, a rotor 5 is formed, which has a rotor hub 6 with rotor blades 7 arranged thereon. The rotor hub 6 is considered part of the nacelle 2. The rotor hub 6 is rotatably mounted on the nacelle housing 4 by means of a rotor bearing 8. In particular, it is provided that a plain bearing 9 according to the invention and described in more detail below is used as the rotor bearing 8.

[0078] The rotor bearing 8, which is used to support the rotor hub 6 on the nacelle housing 4 of the nacelle

[0079] 2, is designed to absorb a radial force 10 and an axial force 11. The axial force 11 is caused by the force of the wind. The radial force 10 is caused by the weight of the rotor 5 and acts on the center of gravity of the rotor 5. Since the center of gravity of the rotor 5 lies outside the rotor bearing 8, a tilting moment 12 is caused in the rotor bearing 8 by the radial force 10. The tilting moment 12 can also be caused by an uneven load on the rotor blades 7. This tilting moment 12 can be absorbed by means of a second plain bearing, which is arranged at a distance from the plain bearing 9 according to the invention.

[0080] The rotor bearing 8 according to the invention can, for example, have a diameter between 0.5 m and 5 m. Of course, it is also conceivable for the rotor bearing 8 to be smaller or larger.

[0081] Fig. 2 shows a first embodiment of the gondola 2 with the sliding bearing 9. The sliding bearing 9 is shown in Fig. 2 in a longitudinal section.

[0082] Of course, the plain bearing 9 shown in Fig. 2 can also be used in all other industrial applications outside of wind turbines. As can be seen from Fig. 2, the plain bearing 9 can be provided with an inner ring element 13 and an outer ring element 14. Between the inner ring element 13 and the outer ring element 14, a plain bearing element 15 is arranged, which serves to provide rotational plain support for the inner ring element 13 relative to the outer ring element 14. The inner ring element 13 and the outer ring element 14 are rotatable relative to one another about a rotation axis 16.

[0083] In the embodiment shown in Fig. 2, the inner ring element 13 is formed directly by a rotor shaft 17.

[0084] The rotor shaft 17 is shown schematically in Fig. 2. As can be seen from Fig. 2, the rotor shaft 17 can be provided with a rotor side 18. The rotor side 18 serves to accommodate the rotor hub 6, or the rotor hub 6 can be formed directly on the rotor side 18.

[0085] As further evident from Fig. 2, it can be provided that a first rotor shaft bearing 19 and a second rotor shaft bearing 20 are formed. The first rotor shaft bearing 19 can be arranged closer to the rotor hub 6 or to the rotor side 18 than the second rotor shaft bearing 20. In particular, it can be provided that the second rotor shaft bearing 20 is designed as a plain bearing 9 in accordance with the following explanations. The first rotor shaft bearing 19 can be designed as a loose bearing. The second rotor shaft bearing 20 can be designed as a fixed bearing.

[0086] Furthermore, it can be provided that the outer ring element 14 is coupled to the nacelle housing 4 by means of a bearing holder 21. In the exemplary embodiment shown in Fig. 2, it is thus provided that the outer ring element 14 is rigidly coupled to the nacelle housing 4 and the inner ring element 13 is rotatable relative to the outer ring element 14 with respect to a rotation axis 16 by means of the plain bearing element 15. Since in this exemplary embodiment the rotor shaft 17, which can be coupled to the rotor hub 6 and thus to the rotor 5, directly forms the inner ring element 13, the rotor shaft 17 can thus be rotatably received in the nacelle housing 4 by means of the plain bearing 9.

[0087] Fig. 3 shows the plain bearing 9 of Fig. 2 in a perspective view. For the sake of clarity, the outer ring element 14 has been axially displaced in an exploded view in Fig. 3 to illustrate the details of the plain bearing 9. The bearing holder 21 has also been hidden. The plain bearing 9 will be described below using a combined view of Figs. 2 and 3.

[0088] As can be seen from Fig. 3, the sliding bearing element 15 comprises a plurality of individual sliding bearing pads 22, which are arranged distributed over the circumference between the inner ring element 13 and the outer ring element 14.

[0089] The individual plain bearing pads 22 can each be coupled to the inner ring element 13 by means of a fastening means 23.

[0090] In particular, it can be provided that the individual plain bearing pads 22 have a shoulder 25 on their inner side 24. The shoulder 25 can form a contact surface so that the plain bearing pad 22 can bear against an axial stop 26 of the inner ring element 13 in the region of the shoulder 25. This allows the plain bearing pad 22 to be positioned in the axial direction relative to the inner ring element 13.

[0091] In particular, it can be provided that the fastening means 23 is designed in the form of a fastening screw, by means of which the individual plain bearing pads 22 can be pressed in the axial direction against the axial stop 26 and can thus be fixed.

[0092] The individual plain bearing pads 22 can thus, due to the described structure, be firmly connected to the inner ring element 13 in the operating state of the plain bearing 9 and thus rotate with it relative to the outer ring element 14. To enable the rotational movement between the inner ring element 13 and the outer ring element 14, a bearing surface 27 is formed on each of the individual plain bearing pads 22, which, in the ready-to-use state of the plain bearing 9, rests at least partially against a counter surface 28 of the outer ring element 14.

[0093] The counter surface 28 is arranged on an inner side 29 of the outer ring element 14. The bearing surface 27 of the plain bearing pad 22 and the counter surface 28 of the outer ring element 14 are designed as sliding surfaces that slide against each other during operation of the plain bearing 9. In particular, it can be provided that the counter surface 28 of the outer ring element 14 is designed as a hard, wear-resistant surface, which can be formed, for example, from hardened steel. The bearing surface 27 of the plain bearing pad 22 can be formed from a plain bearing material that is softer than the counter surface 28. Of course, it is also conceivable for the bearing surface 27 to have a sliding coating.

[0094] As can be seen from Figs. 2 and 3, it can be provided that a removal opening 30 is formed, which can serve for the removal of individual plain bearing pads 22. The removal opening 30 can interrupt the counter surface 28 formed in the outer ring element 14, at least in sections. In particular, it can be provided that the removal opening 30 extends from a first end face 31 of the outer ring element 14. In particular, it can be provided that the removal opening 30 does not extend to a second end face 32 of the outer ring element 14. Rather, the removal opening 30 can extend only to an axial apex 33.

[0095] To replace the individual plain bearing pads 22, it is not necessary for the shaft load to be absorbed by an external bearing. Instead, it can be provided that only a single plain bearing pad 22 is replaced with a new plain bearing pad 22 at a time. This process is repeated until all plain bearing pads 22 have been replaced. In this case, the fastening means 23 can be loosened, and after removing the fastening means 23, the free plain bearing pad 22 can be pulled out of the inner ring element 13 in the axial direction.

[0096] A new plain bearing pad 22 can then be inserted into the position of the old plain bearing pad 22 according to the above description. The newly inserted plain bearing pad 22 can then be secured, and the inner ring element 13 can then be rotated so that the next plain bearing pad can be replaced according to the steps described above. This process can be repeated until all plain bearing pads 22 have been replaced.

[0097] Fig. 4 shows a perspective view of the plain bearing pad 22, wherein the same reference numerals or component designations are used for the same parts as in the preceding Figures 1 to 3. To avoid unnecessary repetition, reference is made to the detailed description in the preceding Figures 1 to 3.

[0098] Fig. 5 shows a cross-sectional view of the plain bearing 9, wherein the same reference numerals or component designations are used for the same parts as in the preceding Figures 1 to 4. To avoid unnecessary repetition, reference is made to the detailed description in the preceding Figures 1 to 4.

[0099] In Fig. 6, a segment of the bearing surface 27 is drawn on a structurally represented torus, with the first radius 34 and the second radius 35 being drawn.

[0100] For the cross-sectional view of Fig. 5, a cutting line according to VV in Fig. 2 was chosen, whereby the cutting line runs exactly through the axial vertex 33.

[0101] The inventive design of the plain bearing pad 22 is described with reference to a synopsis of Figures 2 to 5.

[0102] As can be seen from Figs. 2 to 6, it can be provided that the bearing surface 27 has a first radius 34 and a second radius 35. The second radius 35 extends from the rotation axis 16 to the axial vertex 33. In particular, it can be provided that the second radius 35 runs in the circumferential direction of the bearing surface 27.

[0103] The first radius 34 extends in the axial direction. As can be seen from the figures, the first radius 34 can have a first center point 36. The first center point

[0104] 36 may lie in the plane of the axial vertex 33 and be spaced from the rotation axis 16 at a center distance 38.

[0105] The second radius 35 may have a second center point 37. The second center point

[0106] 37 can lie on the rotation axis 16. In particular, it can be provided that, through the formation of the first radius 34 and the second radius 35, the bearing surface 27 forms a segment of an envelope surface of a torus with a circular cross-sectional area.

[0107] As further apparent from Figures 2 to 6, the plain bearing pad 22 can be provided to extend in the axial direction from the axial vertex 33 in a first axial extension 39 and from the axial vertex 33 in a second axial extension 40. The first axial extension 39 and the second axial extension 40 together result in a plain bearing pad width 41.

[0108] As can be seen particularly clearly in Fig. 2, the first axial extension 39 can be larger than the second axial extension 40. This measure draws the plain bearing pad 22 further inward on the first end face 31 of the outer ring element 14 than on the second end face 32 of the outer ring element 14. Thus, the plain bearing 9 can absorb a higher axial force in a first axial direction than in a second axial direction. The reasons for this and the advantages of the inventive design are explained with reference to Fig. 7.

[0109] Fig. 7 shows a detailed view of the plain bearing 9, as shown in Fig. 2, wherein the same reference numerals or component designations are used for the same parts as in the preceding Figs. 1 to 6. To avoid unnecessary repetition, reference is made to the detailed description in the preceding Figs. 1 to 6.

[0110] As can be seen from Fig. 7, the selection of the first radius 34 and the first axial extension 39 results in a first axial overlap 42. The first axial overlap 42 determines the projected axial bearing surface, whereby the axial load capacity of the plain bearing 9 can be determined.

[0111] Analogously, a second axial overlap 43 is determined by the first radius 34 and the second axial extension 40. The second axial overlap 43 determines a projected axial bearing surface and thus defines the possible load capacity of the plain bearing 9 in a second axial direction.

[0112] The possible load capacity of the plain bearing 9 in the radial direction is determined by the plain bearing pad width 41.

[0113] To illustrate the advantages over a plain bearing pad with a spherical cap surface, a comparable spherical cap surface 44 is shown schematically in Fig. 7. The spherical cap surface 44 would have a spherical cap radius 45 which would be the same size as the second radius 35. As can be seen particularly well from Fig. 7, a third axial overlap 46 of the spherical cap surface 44 would thus be significantly smaller than the first axial overlap 42. A plain bearing designed in this way with a spherical cap surface 44 could therefore absorb only a lower axial load with the same plain bearing pad width 41.

[0114] In an embodiment not shown, contrary to the embodiment of Figures 2 to 7, it can be provided that the second radius 35 is smaller than the first radius 34. In such an embodiment, the bearing surface 27 has a basic shape similar to an “American football”.

[0115] Fig. 8 shows a further and possibly independent embodiment of the plain bearing 9, wherein the same reference numerals or component designations are used for the same parts as in the preceding Figs. 1 to 7. To avoid unnecessary repetition, reference is made to the detailed description in the preceding Figs. 1 to 7.

[0116] As can be seen from Fig. 8, it can be provided that the inner ring element 13 is designed as a structurally independent element which is received on the rotor shaft 17.

[0117] Fig. 9 shows a further and possibly independent embodiment of the plain bearing 9, wherein the same reference numerals or component designations are used for the same parts as in the preceding Figs. 1 to 8. To avoid unnecessary repetition, reference is made to the detailed description in the preceding Figs. 1 to 8.

[0118] As can be seen from Fig. 9, the plain bearing pads 22 can be attached to the outer ring element 14. The counter surface 28 can thus be formed on the inner ring element 13. In the exemplary embodiment shown in Fig. 9, the inner ring element 13 can be formed as part of the rotor shaft 17.

[0119] In an alternative embodiment variant not shown, based on the embodiment according to Fig. 9, it can also be provided that the inner ring element 13, on which the counter surface 28 is formed, is designed in the form of an independently formed component which is received on the rotor shaft 17.

[0120] The exemplary embodiments show possible embodiments. It should be noted at this point that the invention is not limited to the specifically illustrated embodiments. Rather, various combinations of the individual embodiments are also possible. This variation possibility, based on the teaching of technical action based on the invention in question, lies within the skill of the person skilled in the art. The scope of protection is determined by the claims. However, the description and drawings must be used to interpret the claims. Individual features or combinations of features from the various exemplary embodiments shown and described may represent independent inventive solutions in themselves. The problem underlying the independent inventive solutions can be derived from the description.

[0121] All information on value ranges in this description is to be understood as including any and all sub-ranges thereof, e.g. the information 1 to 10 is to be understood as including all sub-ranges starting from the lower limit of 1 and the upper limit of 10, ie all sub-ranges begin with a lower limit of 1 or greater and end with an upper limit of 10 or less, e.g. 1 to 1.7, or 3.2 to 8.1, or 5.5 to 10.

[0122] For the sake of clarity, it should finally be pointed out that, in order to better understand the structure, some elements have been shown out of scale and / or enlarged and / or reduced in size.

[0123] Reference symbol list

[0124] Wind turbine 30 Nacelle removal opening 31 first end face outer ring element

[0125] Tower ment

[0126] Nacelle casing 32 second end face outer ring element rotor element

[0127] Rotomabe 33 axial vertex

[0128] Rotor blade 34 first radius

[0129] Rotor bearing 35 second radius Plain bearing 36 first center point Radial force 37 second center point

[0130] Axial force 38 center distance

[0131] Tilting moment 39 First axial extent of inner ring element 40 Second axial extent of outer ring element 41 Plain bearing pad width of plain bearing element 42 First axial overlap of rotation axis 43 Second axial overlap

[0132] Rotor shaft 44 spherical cap surface

[0133] Rotor side 45 spherical cap radius first rotor shaft bearing 46 third axial overlap second rotor shaft bearing bearing holder plain bearing pad

[0134] Fasteners inside

[0135] Paragraph

[0136] Axial stop

[0137] Bearing surface Counter surface Inside

Claims

Patent claims 1. Plain bearing (9) comprising: - an inner ring element (13); - an outer ring element (14); - at least one plain bearing element (15) which is arranged between the inner ring element (13) and the outer ring element (14), wherein the outer ring element (14) and the inner ring element (13) are mounted rotatably relative to one another about a rotation axis (16) by means of the plain bearing element (15), wherein the plain bearing element (15) comprises a plurality of plain bearing pads (22), wherein the individual plain bearing pads (22) each have a curved bearing surface (27), characterized in that the curved bearing surface (27) has a first radius (34) in a longitudinal section along the rotation axis (16) and has a second radius (35) in a cross-section normal to the rotation axis (16), in particular that the second radius (35) is larger than the first radius (34).

2. Plain bearing (9) according to claim 1, characterized in that the bearing surface (27) of the plain bearing pads (22) is each designed as a torus segment of a torus with a circular cross-section.

3. Plain bearing (9) according to claim 1 or 2, characterized in that the first radius (34) is between 5% and 99%, in particular between 10% and 50%, preferably between 15% and 30% of the second radius (35).

4. Plain bearing (9) according to one of claims 1 to 3, characterized in that the second radius (35) is measured at an axial vertex (33).

5. Plain bearing (9) according to claim 4, characterized in that the plain bearing pads (22) have, starting from the axial apex (33), a first axial extension (39) in a first axial direction and a second axial extension (40) in a second axial direction, wherein the first axial extension (39) is greater than the second axial extension (40).

6. Plain bearing (9) according to claim 5, characterized in that the second axial extent (40) is between 5% and 99%, in particular between 20% and 95%, preferably between 50% and 80% of the first axial extent (39).

7. Plain bearing (9) according to claim 4, characterized in that the plain bearing pads (22) have, starting from the axial apex (33), a first axial extension (39) in a first axial direction and a second axial extension (40) in a second axial direction, wherein the first axial extension (39) is of the same size as the second axial extension (40).

8. Plain bearing (9) according to one of the preceding claims, characterized in that the plain bearing pads (22) have a plain bearing pad width (41), wherein the plain bearing pad width (41) is between 20% and 170%, in particular between 60% and 140%, preferably between 90% and 120% of the first radius (34).

9. Plain bearing (9) according to one of the preceding claims, characterized in that the second radius (35) has a different value from the first radius (34), wherein the first radius (34) has a constant value over the entire axial extent of the bearing surface.

10. Plain bearing (9) according to one of the preceding claims, characterized in that the second radius (35) is smaller than the first radius (34).

11. Nacelle (2) for a wind turbine (1), the nacelle (2) comprising: - a nacelle casing (4); - a rotor hub (6); - a rotor bearing (8) for supporting the rotor hub (6) on the nacelle housing (4), characterized in that the rotor bearing (8) comprises a plain bearing (9) according to one of the preceding claims, which has plain bearing pads (22).

12. Nacelle (2) according to claim 11, characterized in that the sliding bearing pads (22) of the sliding bearing (9) form a first Axial extension (39) in a first axial direction and a second axial extension (40) in a second axial direction, wherein the first axial extension (39) is greater than the second axial extension (40), wherein the plain bearing pads (22) are accommodated in the nacelle housing (4) in such a way that the first axial extension (39) is formed on a side of the axial apex (33) facing away from the rotor hub (6).

13. Nacelle (2) according to claim 11 or 12, characterized in that a first rotor shaft bearing (19) and a second rotor shaft bearing (20) are formed, wherein the first rotor shaft bearing (19) is arranged closer to the rotor hub (6) than the second rotor shaft bearing (20), wherein the second rotor shaft bearing (20) is designed as a plain bearing (9) according to one of claims 1 to 8.

14. Nacelle (2) according to one of claims 11 to 13, characterized in that the plain bearing pads (22) are attached to a rotor shaft (17).

15. Nacelle (2) according to one of claims 11 to 14, characterized in that the plain bearing pads (22) are fastened to the nacelle housing (4).

16. Wind turbine (1) with a nacelle (2), the nacelle (2) comprising: - a nacelle casing (4); - a rotor hub (6) with rotor blades arranged thereon; - a rotor bearing (8) for supporting the rotor hub (6) on the nacelle housing (4), characterized in that the rotor bearing (8) comprises a plain bearing (9) according to one of claims 1 to 10.

Images