BEARING HOUSING

Abstract

A bearing housing is configured as an end-side cover for a nacelle of a fluid-flow power plant and includes a cylindrical section having an interior and a bearing unit in the interior. The bearing unit includes at least one rolling-element bearing having an inner ring and an outer ring rotatably disposed with respect to each other about a bearing rotational axis and a plurality of rolling elements between the rings. A pressure line of the bearing intersects the bearing rotational axis at a first angle. An angled section of the housing extends from the cylindrical section of the housing at a second angle that is related to, and preferably substantially equal to, the first angle.

Claims

1. A bearing housing configured as an end-side cover for a nacelle of a fluid-flow power plant, the bearing housing comprising: a cylindrical section having an interior; a bearing unit in the interior, the bearing unit including a first rolling-element bearing having an inner ring and an outer ring rotatably disposed with respect to each other about a bearing rotational axis and defining a rolling space between them, and a first plurality of rolling elements disposed in the rolling space, a pressure line of the first bearing intersecting the bearing rotational axis at a first angle, and an angled section extending radially outward from the cylindrical section at a second angle, the second angle being related to the first angle.

2. The bearing housing according to claim 1, wherein the first angle is substantially equal to the second angle.

3. The bearing housing according to claim 2, wherein the angled section is positioned relative to the first bearing such that the pressure line of the first bearing extends through the angled section.

4. The bearing housing according to claim 3, wherein the angled section has a first end at the cylindrical section and a second end spaced from the first end, and a flange attached to the second end, and wherein the pressure line of the first bearing extends through the first end and the second end.

5. The bearing housing according to claim 3, wherein the pressure line of the first bearing is parallel to an outer surface of the angled section or is parallel to an inner surface of the angled section or is parallel to an axial centerline of the angled section.

6. The bearing housing according to claim 2, wherein the bearing unit includes a second rolling-element bearing, the second rolling-element bearing including an inner ring and an outer ring that are disposed rotatably with respect to each other about the bearing rotational axis and define a second rolling space between them, and a second plurality of rolling elements in the second rolling space, a pressure line of the second bearing intersecting the bearing rotational axis at a second angle, and wherein the second rolling-element bearing is disposed such that the pressure line of the second bearing intersects the pressure line of the first bearing at a location radially outward of the cylindrical section.

7. The bearing housing according to claim 6, wherein the angled section has a first end at the cylindrical section and a second end spaced from the first end, and a flange attached to the second end, and wherein the angled section extends from the cylindrical section to the location.

8. The bearing housing according to claim 2, wherein the angled section has a first end at the cylindrical section and a second end spaced from the first end, and wherein a plurality of stiffening ribs extend from the cylindrical section to the second end of the angled section.

9. The bearing housing according to claim 8, wherein an angle between the cylindrical section and one of the plurality of stiffening ribs is substantially equal to an angle between the bearing rotational axis and the pressure line of the second bearing.

10. The bearing housing according to claim 8, wherein an angle between the cylindrical section and one of the plurality of stiffening ribs is based on an angle between the bearing rotational axis and the pressure line of the second bearing.

11. The bearing housing according to claim 10, wherein each of the plurality of stiffening ribs has a concave edge.

12. The bearing housing according to claim 10, wherein each of the plurality of stiffening ribs has a elliptically concave edge.

13. The bearing housing according to claim 11, wherein at least one of the plurality of stiffening ribs is reinforced.

14. A nacelle for a fluid-flow power plant comprising: a nacelle housing having a circular end opening, and the bearing housing according to claim 2 mounted at the end opening to close the opening; wherein the angled section has a first end at the cylindrical section and a second end connected to the circular opening of the nacelle housing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] FIG. 1 is a partial sectional view through a fluid-flow power plant including a bearing housing according to one embodiment of the present disclosure.

DETAILED DESCRIPTION

[0025] In the following, identical or functionally equivalent elements are designated by the same reference numbers.

[0026] FIG. 1 shows a partial section through a fluid-flow power plant 1. The fluid-flow power plant 1 comprises a rotor 3 including a blade hub 2 on which a plurality of rotor blades 4 are disposed. Due to a flow of a fluid, such as, for example, water or air, the blade hub 2 is set into rotation via the rotor blades 4, wherein the rotation is transmitted to a rotor shaft 6. Forces F.sub.x, F.sub.y, F.sub.z which result from the flow of fluid against the rotor blades 4, blade bending moments M.sub.y, M.sub.z, and the drive moment M.sub.x, are transmitted via the blade hub 2 onto the rotor shaft 6 and its bearing assembly.

[0027] The rotor shaft 6 can be attached, for example, via a screw connection 8 to the blade hub 2. On the end of the rotor shaft 6 opposite the blade hub 2, the rotor shaft 6 is coupled via a shaft coupling 10 to a transmission 12, which is in turn connected to a generator (not shown). Here the shaft coupling 10 produces the fixed connection between the rotor shaft 6 and the transmission 12. Furthermore, the fluid-flow power plant 1 has a nacelle 11, in which the rotor shaft 6, the shaft coupling 10, the transmission 12, and also the generator are received.

[0028] In order to cover an opening in the nacelle 11 and simultaneously form a cover for the bearing assembly of the rotor shaft 6, a bearing housing 14 is provided that includes a cylindrical section 16. The cylindrical section 16 is configured to carry a bearing unit 18 that includes a first rolling-element bearing 20 and a second rolling-element bearing 22. Each of the rolling-element bearings 20, 22 includes an inner ring and an outer ring that are rotatably disposed with respect to each other about a bearing rotational axis 24 and that define a rolling space between them in which a plurality of rolling elements are disposed. In the exemplary embodiment depicted in FIG. 1, the rolling-element bearings are tapered roller bearings, and the rolling elements are tapered rollers. Tapered roller bearings are highly loadable both in both the axial and radial direction and are therefore well-suited for a use in the shaft bearing assembly of the rotor. Of course, other bearing types, such as, for example, angular contact ball bearings or axial spherical roller bearings can also be used in combination with an additional radial bearing.

[0029] The first rolling-element bearing 20 is disposed on an end of the cylindrical section 16 facing the blade hub 2, such that its pressure line 28 defines an angle α with the bearing rotational axis. On the end of the cylindrical section 16 facing away from the blade hub 2, the second rolling-element bearing 22 is disposed at a spacing 21 from the first rolling-element bearing 20, and the pressure line 30 of the second bearing defines an angle β with the bearing rotational axis 24. Here the two rolling-element bearings 20, 22 are disposed such that the pressure line 28 of the first rolling-element bearing 20 and the pressure line 30 of the second rolling-element bearing intersect radially outwardly of the two rolling-element bearings 20, 22. The angles α and β are identical to each other in value in the exemplary embodiment shown in FIG. 1.

[0030] The bearing housing 14 furthermore has an angularly extending section 26. Here the angle α′ between the angularly extending section 26 and the cylindrical section 16 essentially corresponds to the angle α between the bearing rotational axis 24 and the pressure line 28 of the first rolling-element bearing 20. The angularly extending section 26 thereby extends radially outward along the pressure line 28 of the first rolling-element bearing 20.

[0031] On the side of the angularly extending section 26 facing away from the blade hub 2, a plurality of stiffening ribs 36 are provided that connect a free end 27 of the angularly extending section 26 and the cylindrical section 16. The plurality of stiffening ribs 36 are elliptically curved so that the stiffening ribs 36 are loaded over their entire length, and not only pointwise. Furthermore, each of the stiffening ribs 36 forms an angle (3′ with the cylindrical section 16 that essentially corresponds to the angle θ between the pressure line 30 of the second bearing 22 and the bearing rotational axis 24.

[0032] The curvature also allows a certain force dissipation to be effected so that a force acting toward the second pressure line can also be diverted toward the nacelle and introduced into the nacelle.

[0033] As can be seen in FIG. 1, the angularly extending section 26 extends up to the intersection point of the pressure lines 28, 30 of the two rolling-element bearings 20, 22. In the region of the intersection point of the pressure lines 28, 30 of the two rolling-element bearings 20, 22, the angularly extending section 26 is provided with a flange 32, by which the bearing housing 14 is connected to the nacelle 11 using a screw connection 34. The acting forces and moments can thereby be dissipated via the flange 32 onto the nacelle 11.

[0034] Furthermore, seals 38, 40 are provided on the side of the cylindrical section 16 facing the rotor 3 and on the side of the cylindrical section facing the nacelle 11, which seals seal the bearing housing outwardly and toward the nacelle 11.

[0035] In summary, providing a bearing housing 14 that has a section 26 extending angularly with respect to a cylindrical section 16 allows a steady flow of force to be directed to the nacelle 11 of the turbine. For this purpose an angle α′ of the angular section 26 is related to the angle α between the bearing rotational axis 24 and the pressure line 28 of the rolling-element bearing 20. Force is thereby dissipated in the direction of the pressure line 28 of the rolling-element bearing 20 and can be introduced via the flange 32 into the screw connection 34 to the housing 11. In addition, the force dissipation can be improved by providing stiffening ribs 36, whose angle (3′ with respect to the cylindrical section 16 is related to the angle β between the pressure line 30 of the second rolling-element bearing 22 and the bearing rotational axis 24. These stiffening ribs on the one hand support the angular section 26, and simultaneously allow a dissipation of the forces acting on the second rolling-element bearing toward the nacelle. For this purpose the stiffening ribs are preferably curved concavely, wherein the curvature is configured in particular elliptical.

[0036] Representative, non-limiting examples of the present invention were described above in detail with reference to the attached drawings. This detailed description is merely intended to teach a person of skill in the art further details for practicing preferred aspects of the present teachings and is not intended to limit the scope of the invention. Furthermore, each of the additional features and teachings disclosed above may be utilized separately or in conjunction with other features and teachings to provide improved bearing housings for fluid power plants.

[0037] Moreover, combinations of features and steps disclosed in the above detailed description may not be necessary to practice the invention in the broadest sense, and are instead taught merely to particularly describe representative examples of the invention. Furthermore, various features of the above-described representative examples, as well as the various independent and dependent claims below, may be combined in ways that are not specifically and explicitly enumerated in order to provide additional useful embodiments of the present teachings.

[0038] All features disclosed in the description and/or the claims are intended to be disclosed separately and independently from each other for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter, independent of the compositions of the features in the embodiments and/or the claims. In addition, all value ranges or indications of groups of entities are intended to disclose every possible intermediate value or intermediate entity for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter.

REFERENCE NUMBER LIST

[0039] 1 Fluid-flow power plant [0040] 2 Blade hub [0041] 3 Rotor [0042] 4 Rotor blade [0043] 6 Rotor shaft [0044] 8 Screw connection [0045] 10 Shaft coupling [0046] 11 Nacelle [0047] 12 Transmission [0048] 14 Bearing housing [0049] 16 Cylindrical section [0050] 18 Bearing unit [0051] 20, 22 Rolling-element bearing [0052] 21 Bearing spacing [0053] 24 Bearing rotational axis [0054] 26 Angled section [0055] 27 Free end of the angled section [0056] 28, 30 Pressure line [0057] 32 Flange [0058] 34 Screw connection [0059] 36 Stiffening ribs [0060] 38, 40 Seal [0061] α, α′, β, β′ Angles [0062] F.sub.x, F.sub.y, F.sub.z Forces [0063] M.sub.x, M.sub.y, M.sub.z Bending moments