Bearing unit for a rotor unit of a wind turbine and wind turbine

Abstract

The invention relates to a bearing unit for a rotor unit of a wind turbine, comprising a first bearing ring, a second bearing ring, a plurality of rolling elements and a sealing member, the sealing member comprising a sealing member base portion, a first sealing member tip portion and a second sealing member tip portion, wherein the first sealing member tip portion abuts a first wall of the first bearing ring and the second sealing member tip portion abuts a second wall of the bearing unit, wherein the sealing member is configured and arranged so that a first contact pressure between the first sealing member tip portion and the first wall is transmitted to the second sealing member tip portion through the sealing member to increase a second contact pressure between the second sealing member tip portion and the second wall. The invention further relates to a wind turbine.

Description

Technical Field

[0001] The invention relates to a bearing unit for a rotor unit of a wind turbine. Furthermore, the invention relates to a wind turbine comprising the bearing unit. Background Art

[0002] A common wind turbine comprises a rotor unit with a plurality of rotor blades and a rotor shaft, a transmission unit for converting a low rotation speed of the rotor shaft into a high rotation speed of a high-speed shaft, and a generator unit for generating electricity by the rotational movement of the high-speed shaft. The rotor unit is pivotally mounted to a housing unit of the wind turbine by means of a bearing unit, wherein the transmission unit and the generator unit are located inside the housing unit. The housing unit is also denoted as a "nacelle".

[0003] The bearing unit is usually configured as a roller bearing with an inner bearing ring, an outer bearing ring and a set of rolling elements arranged in a free space between the inner bearing ring and the outer bearing ring. The rolling elements may be cylindrically shaped and arranged at an angle relative to the axis of rotation of the bearing unit. To ensure less friction and wear, a lubricant, such as grease or the like, is provided in the free space.

[0004] In order to avoid grease leakage and contamination of the grease, a sealing member is provided for sealing the side of the free space facing the environment of the bearing unit. Such a sealing member is usually configured as a radial shaft sealing member. The sealing member has a grease side facing the grease and an environment side facing the environment of the bearing unit.

[0005] Typically, the sealing member is clamped to the outer bearing ring, wherein the first sealing lip is in close contact with the inner bearing ring. In addition, such a sealing member may include a second sealing lip, which is spaced apart from the first sealing lip on the environmental side of the first sealing lip and also contacts the inner bearing ring. The contact pressure of the second sealing lip is typically provided only by the material of the second sealing lip.

[0006] To ensure sufficient contact pressure between the first sealing lip and the inner bearing ring, a spring member, in particular a garter spring, is provided at the first sealing lip. The garter spring is located on the grease side of the first sealing lip in a circumferential groove of the first sealing lip.

[0007] Conventional bearing units have several disadvantages. Firstly, the garter spring is difficult to assemble, since it is located on the grease side of the sealing member. Secondly, it is difficult to control the correct placement of the garter spring when the sealing member is already in the assembled state. Thirdly, during operation, the garter spring may slip out of the groove of the first sealing lip due to poor assembly, material failure, wear, etc. As a result, the first sealing lip and the inner bearing ring may lose their mutual contact pressure. As a result, the sealing member may lose its sealing properties and the bearing unit may be very easily damaged. Summary of the invention

[0008] Therefore, it is an object of the present invention to provide a bearing unit for a rotor unit of a wind turbine and a wind turbine which do not have the disadvantages of prior art solutions. In particular, it is an object of the present invention to provide a bearing unit and a wind turbine which are easier to assemble and / or have a reduced risk of grease leakage due to failure of sealing components.

[0009] This problem is solved by the claims. Therefore, this problem is solved by a bearing unit for a rotor unit of a wind turbine according to independent claim 1 and a wind turbine according to independent claim 10. Further details of the invention emerge from the dependent claims as well as the description and the drawings.

[0010] According to a first aspect of the invention, the problem is solved by a bearing unit for a rotor unit of a wind turbine. The bearing unit comprises a first bearing ring for mounting to a first rotor unit part of the rotor unit, a second bearing ring for mounting to a second rotor unit part of the rotor unit, a plurality of rolling elements located in a free space between the first bearing ring and the second bearing ring for supporting a relative rotational movement between the first bearing ring and the second bearing ring about the axis of rotation of the bearing unit, and a sealing member for sealing the free space on the side facing the environment of the bearing unit, preferably by contacting the first bearing ring and the second bearing ring. The sealing member comprises a sealing member base portion and a first sealing member tip portion protruding from the sealing member base portion in the direction of the first bearing ring. According to the invention, the sealing member comprises a second sealing member tip portion protruding from the sealing member base portion in the direction of the first bearing ring. The first sealing member tip portion abuts a first wall of the first bearing ring, and the second sealing member tip portion abuts a second wall of the bearing unit, wherein the second wall faces the first wall. The sealing member is configured and arranged so that a first contact pressure between the first sealing member tip portion and the first wall is transmitted to the second sealing member tip portion through the sealing member, preferably through the sealing member base portion, to increase a second contact pressure between the second sealing member tip portion and the second wall.

[0011] The bearing unit is configured as a roller bearing unit of standard components having a first bearing ring, a second bearing ring and rolling elements. By means of the rolling elements, a rotational movement between the first bearing ring and the second bearing ring about the axis of rotation is ensured. Since the first bearing ring is configured for mounting to a first rotor unit component and the second bearing ring is configured for mounting to a second rotor unit component, the bearing unit is configured for a pivoting arrangement of the first rotor unit component to the second rotor unit component.

[0012] To prevent grease leakage and contamination of the grease by environmental influences such as water, dust, etc., the bearing unit comprises a sealing member. Preferably, the bearing unit comprises at least one sealing member on each open side of the free space towards the environment. Thus, preferably, the bearing unit comprises two or at least two sealing members. The sealing members are preferably arranged coaxially with respect to the axis of rotation.

[0013] The sealing member comprises a sealing member base portion, which is configured to be clamped to the second bearing ring. Therefore, preferably, the sealing member base portion is made of a complete material to ensure sufficient clamping force. In addition or alternatively, the cross-section of the sealing member base portion may include pores, passages, etc. The cross-section of the sealing member base portion is preferably rectangular or at least roughly rectangular. According to the present invention, roughly rectangular means a rectangle with at least one difference from a rectangular shape (such as a curve, an edge, etc.). The sealing member base portion may be a trapezoid, wherein the bottom of the trapezoid faces away from the first sealing member tip portion. According to the present invention, the sealing member can be clamped to the second bearing ring directly or by means of a mounting unit, and the mounting unit is preferably fixedly attached to the second bearing ring by screws, bolts, etc.

[0014] The first sealing member tip portion and the second sealing member tip portion each protrude from the sealing member base portion in the direction of the first bearing ring. Preferably, in a stress-free state, for example, before the sealing member is assembled in the bearing unit, the first sealing member tip portion and the second sealing member tip portion are arranged in a spread out manner from the sealing member base portion. Further preferably, in a stressed state, when the sealing member is assembled in the bearing unit, the first sealing member tip portion and the second sealing member tip portion are arranged in parallel or at least approximately in parallel. Preferably, the first wall is parallel or at least approximately parallel to the second wall. Preferably, the first sealing member tip portion and the second sealing member tip portion are configured so that they form a u-shape or a v-shape.

[0015] According to the present invention, the first sealing member tip portion and the second sealing member tip portion are mechanically interconnected with each other in the following manner: the lateral force acting on the first sealing member tip portion is transferred to the second sealing member tip portion, and vice versa. In other words, the first sealing member tip portion and the second sealing member tip portion constitute a force transmission unit, such as a spring member. Preferably, the sealing member base portion is a part of this force transmission unit. Additionally or alternatively, an additional force transmission unit for transmitting this force can be integrated in the sealing member. Therefore, the sealing unit is configured to provide sufficient contact pressure between the first sealing member tip portion and the first wall and between the second sealing member tip portion and the second wall. No additional clamping spring is required, and therefore the additional clamping spring will not be mispositioned and / or fall off. The sealing member preferably comprises HNBR, NBR and / or PUR.

[0016] The bearing unit according to the invention has the following advantages over standard bearing units for rotor units of wind turbines: the sealing unit is easier to install, the correct placement of the sealing unit is easier to determine, and the possibility of grease leakage due to contact pressure loss is significantly reduced. Furthermore, the sealing member of the bearing unit provides suitable sealing properties in the axial and radial directions, wherein the sealing member of the standard bearing unit provides suitable sealing properties only in the radial direction.

[0017] According to a preferred embodiment of the present invention, the base portion of the sealing member is clamped to the second bearing ring by means of a clamping plate. Preferably, the base portion of the sealing member is arranged at the shoulder portion of the second bearing ring. The clamping plate is preferably mounted to the second bearing ring by means of screws, bolts, etc. Preferably, the clamping force is limited by the axial width of the shoulder portion. By these means, the maximum clamping force can be achieved when the clamping plate contacts the shoulder portion of the second bearing ring. This has the advantage of improving the assembly of the sealing member. Therefore, the production cost of the bearing unit can be reduced. In addition, since the sealing member can be easily replaced by removing the clamping plate, maintenance is improved.

[0018] Preferably, the first sealing member tip portion and the second sealing member tip portion protrude into the first groove of the first bearing ring, and the sealing member base portion is fixedly attached to the second bearing ring, wherein the first wall is the first side wall of the first groove, and the second wall is the second side wall of the first groove. In other words, both the first sealing member tip portion and the second sealing member tip portion protrude into the groove of the first bearing ring and contact the opposite side walls of the groove to provide a suitable seal. Preferably, the sealing member is assembled to the first bearing ring so that the first sealing member tip portion and the second sealing member tip portion are bent toward each other to fit into the groove, wherein the groove has a width to establish a tension between the first wall and the first sealing member tip portion and between the second wall and the second sealing member tip portion. Preferably, the opening of the first groove is chamfered to improve the assembly of the sealing member into the first groove. Further preferably, the sealing member base portion is assembled into the second groove of the second bearing ring, especially in a press-fit configuration. Preferably, the opening of the second groove is chamfered to improve the assembly of the sealing member into the second groove. This has the advantage of improving the sealing effect of the sealing member. In addition, the sealing member is easy to assemble.

[0019] Advantageously, the second wall is provided by a clamping plate. The clamping plate can be fixed to the first bearing ring or the second bearing ring. In other words, according to a first embodiment, the first sealing member tip portion contacts the first wall of the first bearing ring and the second sealing member tip portion contacts the second wall of the clamping plate, which is fixedly attached to the first bearing ring. In this case, both sealing member tip portions contact the section of the bearing unit that has the same movement relative to the second bearing ring. According to a second embodiment, the first sealing member tip portion contacts the first wall of the first bearing ring and the second sealing member tip portion contacts the second wall of the clamping plate, which is fixedly attached to the second bearing ring. In this embodiment, only the first sealing member tip portion contacts the section of the bearing unit that moves relative to the second bearing ring and the second sealing member tip portion. In this embodiment, preferably, the first bearing ring is configured as an outer ring of the bearing unit, and the second bearing ring is configured as an inner ring of the bearing unit. This has the advantage of improving the assembly of the sealing member.

[0020] Preferably, a lip seal is provided at the gap between the clamping plate and the first bearing ring for sealing the gap. The bottom end of the lip seal is preferably attached to the clamping plate, in particular clamped in a third groove of the clamping plate. The third groove is preferably located at the short side of the clamping plate, which extends circumferentially and axially relative to the rotation axis. Further preferably, the tip end of the lip seal contacts the front side of the first bearing ring. This has the advantage of further improving the sealing of the free space.

[0021] According to a preferred embodiment of the invention, the first bearing ring is configured as an inner ring of the bearing unit and the second bearing ring is configured as an outer ring of the bearing unit. Thus, the sealing member is attached to the outer ring of the bearing unit, wherein both the first sealing member tip portion and the second sealing member tip portion protrude in the direction of the axis of rotation. The first wall is part of the inner ring. In operation, the outer ring rotates relative to the sealing member. This configuration is advantageous for special types of wind turbines with a hollow rotor and a fixed rotor shaft.

[0022] Preferably, the first sealing member tip portion includes a first tip main section adjacent to the sealing member base portion and terminating at the first tip end section, wherein the first tip end section has a larger width and / or includes less flexible material than the adjacent portion of the first tip main section. Preferably, the first tip main section has a width that is constantly reduced from the sealing member base portion to the first tip end section. Further preferably, the width of the first tip end section adjacent to the first tip main section has at least twice the size of the size of the adjacent first tip main section. Preferably, the first tip end section includes a reinforcement, such as a protective layer and / or embedded reinforcing fibers, etc. Preferably, the flexibility of the first tip end section is less than the flexibility of the adjacent first tip main section. The preferred material of the first tip end section and / or the first tip main section is PTFE or the like. Additionally or alternatively, the second sealing member tip portion can be configured in the same manner. This has the advantage of being able to improve the life of the sealing member and thus the sealing effect.

[0023] Further preferably, the first wall comprises a first formed section, wherein the first tip end section contacts the first formed section. Alternatively or in addition, the second wall comprises a second formed section, wherein the second tip end section of the second sealing member tip portion contacts the second formed section. According to the present invention, the formed section comprises at least one shape different from a flat plane. Preferably, the formed section comprises a circular, elliptical, rectangular, trapezoidal, etc. cross section. The formed section can be configured as a bump, a dent, a ramp, a socket, etc. Further preferably, the edge of the formed section is rounded to prevent contamination and / or damage to the sealing member. The first formed section is preferably configured so that the first tip main section is spaced apart from the first wall, or at least partially spaced apart from the first wall. The second formed section is preferably configured so that the second tip main section of the second sealing member tip portion is spaced apart from the second wall, or at least partially spaced apart from the second wall. Preferably, the bearing unit is configured so that most of the contact force between the first sealing member tip portion and the first wall is transmitted via the first tip end section, and / or most of the contact force between the second sealing member tip portion and the second wall is transmitted via the second tip end section. The shaped section has the advantage of improving the sealing effect of the sealing member.

[0024] Preferably, the sealing member comprises an integrated spring member, wherein the spring member extends from the first sealing member tip portion to the second sealing member tip portion. Preferably, the spring member extends from the first sealing member tip portion through the sealing member base portion to the second sealing member tip portion. Preferably, the spring member terminates in the first tip end section or next to the first tip end section and / or in the second tip end section or next to the second tip end section. In other words, the spring member can terminate adjacent to one or two tip end sections. The spring member is configured to provide a reaction force when the first tip end section and the second tip end section are pressed toward each other. Preferably, the spring member has a u-shaped cross section. Further preferably, the spring member comprises stainless steel or is composed of stainless steel. The spring member has the advantage of providing an additional contact force between the sealing member and the first wall and the second wall. Therefore, the sealing effect of the sealing member is improved.

[0025] According to a second aspect of the invention, the problem is solved by a wind turbine. The wind turbine comprises a rotor unit with at least two rotor blades and a rotor shaft, a generator unit for generating electricity by movement of the rotor unit and a bearing unit arranged at the rotor shaft. According to the invention, the bearing unit is configured as a bearing unit according to the first aspect of the invention. Preferably, the rotor shaft is fixed to an outer bearing ring of the bearing unit. Further preferably, the inner bearing ring is fixedly mounted to a housing of the wind turbine. Preferably, the rotor unit comprises three rotor blades, wherein adjacent rotor blades form an angle of 120°. Further preferably, the wind turbine comprises a foundation and a tower, wherein the bottom end of the tower is preferably fixedly attached to the foundation and the housing is rotatably attached to the top end of the tower.

[0026] The wind turbine according to the second aspect of the invention has the same advantages as the bearing unit according to the first aspect of the invention. Therefore, the wind turbine according to the invention has advantages over conventional wind turbines: the sealing unit of the bearing unit is easier to install, it is easier to determine the correct placement of the sealing unit, and the possibility of grease leakage due to contact pressure loss is significantly reduced. In addition, the sealing member of the bearing unit provides appropriate sealing properties in the axial and radial directions, wherein the sealing member of the standard bearing unit only provides appropriate sealing properties in the radial direction. Therefore, the wear of the rotor unit of the wind turbine is reduced, wherein the mountability and reliability of the rotor unit are improved. In addition, the maintenance of the rotor unit of the wind turbine is also improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Further advantages, features and details of the invention are developed from the following description, in which a working example of the invention is described in detail with reference to the accompanying drawings. Thus, the features from the claims as well as the features mentioned in the description may be essential to the invention alone or in any combination. In the drawings:

[0028] Figure 1 shows a schematic cross-sectional side view of a bearing unit according to the prior art,

[0029] Figure 2 shows a schematic cross-sectional side view of a bearing unit according to a first preferred embodiment of the present invention,

[0030] Figure 3 shows a schematic cross-sectional side view of a bearing unit according to a second preferred embodiment of the present invention,

[0031] Figure 4 shows a schematic cross-sectional side view of a sealing unit according to the invention, and

[0032] Figure 5 A schematic side view of a wind turbine according to a preferred embodiment of the invention is shown.

[0033] exist Figures 1 to 5 Elements having the same function and effect are respectively denoted by the same reference numerals. DETAILED DESCRIPTION

[0034] exist Figure 1 , a bearing unit 1 according to the prior art is shown in a schematic cross-sectional side view. The bearing unit 1 comprises a first bearing ring 4 configured as an inner ring of the bearing unit 1, a second bearing ring 6 configured as an outer ring of the bearing unit 1, and a plurality of rolling elements 8 located in a free space 9 between the first bearing ring 4 and the second bearing ring 6. The bearing unit 1 further comprises a sealing member 11 clamped to a mounting unit 30 by means of a clamping plate 17. The mounting unit 30 is fixed to the second bearing ring 6, and the clamping plate 17 is fixed to the mounting unit 30 by means of screws.

[0035] The sealing member 11 comprises a sealing member base portion 12, a first sealing member tip portion 13 and a lip seal 19, the sealing member base portion being clamped between the mounting unit 30 and the clamping plate 17. The first sealing member tip portion 13 is pressed against the first bearing ring 4 by means of a garter spring 29. The lip seal 19 is in contact with the first bearing ring 4. The first sealing member tip portion 13 is located between the rolling element 8 and the lip seal 19.

[0036] Figure 2A bearing unit 1 according to a first preferred embodiment of the present invention is shown in a schematic cross-sectional side view. The bearing unit 1 comprises a first bearing ring 4 configured as an inner ring of the bearing unit 1, a second bearing ring 6 configured as an outer ring of the bearing unit 1, and a plurality of rolling elements 8 located in a free space 9 between the first bearing ring 4 and the second bearing ring 6. The bearing unit 1 further comprises a sealing member 11 clamped to the second bearing ring 6 by means of a clamping plate 17. The clamping plate 17 is fixed to the second bearing ring 6 by means of screws.

[0037] The sealing member 11 comprises a sealing member base portion 12, a first sealing member tip portion 13 with a first tip end section 21, and a second sealing member tip portion 14 with a second tip end section 24. The first tip end section 21 is in contact with a first wall 15 of a first groove 18 of the first bearing ring 4. The second tip end section 24 is in contact with a second wall 16 of the first groove 18, wherein the second wall 16 faces the first wall 15. Therefore, the first sealing member tip portion 13 and the second sealing member tip portion 14 are bent toward each other.

[0038] Figure 3 A bearing unit 1 according to a second preferred embodiment of the present invention is shown in a schematic cross-sectional side view. The bearing unit 1 comprises a first bearing ring 4 configured as an outer ring of the bearing unit 1, a second bearing ring 6 configured as an inner ring of the bearing unit 1, and a plurality of rolling elements 8 located in a free space 9 between the first bearing ring 4 and the second bearing ring 6. The bearing unit 1 further comprises a sealing member 11 clamped to the second bearing ring 6 by means of a clamping plate 17. The clamping plate 17 is fixed to the second bearing ring 6 by means of screws.

[0039] The sealing member 11 comprises a sealing member base portion 12, a first sealing member tip portion 13 with a first tip end section 21, and a second sealing member tip portion 14 with a second tip end section 24. The first tip end section 21 is in contact with a first shaped section 22 of a first wall 15 of a recess of the first bearing ring 4. The second tip end section 24 is in contact with a second shaped section 23 of a second wall 16 of the clamping plate 17, wherein the second wall 16 faces the first wall 15. Thus, the first sealing member tip portion 13 and the second sealing member tip portion 14 are bent towards each other.

[0040] exist Figure 4 In the figure, a sealing member 11 according to the present invention is shown in a schematic cross-sectional side view. The sealing member 11 can be the same as the reference Figure 2 and Figure 3The sealing member 11 is the same as the sealing member shown in the preferred embodiment of the present invention. The sealing member 11 includes a u-shaped spring member 25, which extends from a section of the first sealing member tip part 13 near the first tip end section 21 through the sealing member base part 12 to a section of the second sealing member tip part 14 near the second tip end section 24. In the illustrated state, the spring member 25 is in a stress-free state. With the help of the spring member 25, the force introduced into the first tip end section 21 is transmitted to the second tip end section 24.

[0041] Figure 5 A wind turbine 3 according to a preferred embodiment of the invention is shown in a schematic side view. The wind turbine 3 comprises a tower 32 resting on a foundation 33. On the tower 32, a housing 34 of the wind turbine 3 is pivotably arranged to rotate about a vertical axis. Within the housing 34, a rotor unit 2 of the wind turbine 3 with a rotatable first rotor unit part 5 configured as a rotor shaft 27, a second rotor unit part 7 fixed to the housing 34 and a bearing unit 1 according to the invention to pivot the first rotor unit part 5 at the second rotor unit part 7 about an axis of rotation 10. The rotor blades 26 of the wind turbine 3 are attached to the first rotor unit part 5. In order to convert a low rotation speed of the first rotor unit part 5 into a high rotation speed, the wind turbine 3 comprises a gear unit 31. In order to generate electricity, the wind turbine 3 further comprises a generator unit 28.

Claims

1. A bearing unit (1) for a rotor unit (2) of a wind turbine (3), comprising a first bearing ring (4) for mounting to a first rotor unit part (5) of the rotor unit (2), a second bearing ring (6) for mounting to a second rotor unit part (7) of the rotor unit (2), a plurality of rolling elements (8) located in a free space (9) between the first bearing ring (4) and the second bearing ring (6) for supporting a relative rotational movement between the first bearing ring (4) and the second bearing ring (6) about an axis of rotation (10) of the bearing unit (1), and a sealing member (11) for sealing a side of the free space (9) facing the environment of the bearing unit (1), wherein the sealing member (11) comprises a sealing member base part (12) and a first sealing member tip part (13) protruding from the sealing member base part (12) in the direction of the first bearing ring (4), It is characterized in that The sealing member (11) comprises a second sealing member tip portion (14) protruding from the sealing member base portion (12), wherein the first sealing member tip portion (13) abuts a first wall (15) of the first bearing ring (4), and the second sealing member tip portion (14) abuts a second wall (16) of the bearing unit (1), wherein the second wall (16) faces the first wall (15), and wherein the sealing member (11) is configured and arranged such that a first contact pressure between the first sealing member tip portion (13) and the first wall (15) is transmitted to the second sealing member tip portion (14) through the sealing member (11) to increase a second contact pressure between the second sealing member tip portion (14) and the second wall (16), Wherein, the sealing member (11) comprises an integrated spring member (25), wherein the spring member (25) extends from the first sealing member tip portion (13) to the second sealing member tip portion (14).

2. The bearing unit (1) according to claim 1, It is characterized in that The sealing member base portion (12) is clamped to the second bearing ring (6) by means of a clamping plate (17).

3. The bearing unit (1) according to claim 1 or 2, It is characterized in that The first sealing member tip portion (13) and the second sealing member tip portion (14) protrude into a first groove (18) of the first bearing ring (4), and the sealing member base portion (12) is fixedly attached to the second bearing ring (6), wherein the first wall (15) is a first side wall of the first groove (18), and the second wall (16) is a second side wall of the first groove (18).

4. The bearing unit (1) according to claim 2, It is characterized in that The second wall (16) is provided by the clamping plate (17).

5. The bearing unit (1) according to claim 4, It is characterized in that A lip seal (19) is provided at a gap between the clamping plate (17) and the first bearing ring (4) for sealing the gap.

6. The bearing unit (1) according to any one of claims 1, 2, 4 and 5, It is characterized in that The first bearing ring (4) is configured as an inner ring of the bearing unit (1), and the second bearing ring (6) is configured as an outer ring of the bearing unit (1).

7. The bearing unit (1) according to any one of claims 1, 2, 4 and 5, It is characterized in that The first sealing member tip portion (13) includes a first tip main section (20) starting adjacent to the sealing member base portion (12) and terminating at a first tip end section (21), wherein the first tip end section (21) has a greater width and / or includes less flexible material than adjacent portions of the first tip main section (20).

8. The bearing unit (1) according to claim 7, It is characterized in that The first wall (15) comprises a first formed section (22), wherein the first tip end section (21) is in contact with the first formed section (22), and / or the second wall (16) comprises a second formed section (23), wherein the second tip end section (24) is in contact with the second formed section (23).

9. A wind turbine (3) comprising a rotor unit (2) with a rotor shaft (27) and at least two rotor blades (26), a generator unit (28) for generating electricity by movement of the rotor unit (2), and a bearing unit (1) arranged at the rotor shaft (27), It is characterized in that The bearing unit (1) is configured as a bearing unit (1) according to any one of the preceding claims.

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