Sectional wind turbine blade

Patent metadata

Field	Value
Publication number	US-9388789-B2
Application number	US-201013513002-A
Country	US
Kind code	B2
Filing date	Dec 2, 2010
Priority date	Dec 2, 2009
Publication date	Jul 12, 2016
Grant date	Jul 12, 2016

Abstract

The invention relates to a sectional blade for a wind turbine, the blade comprising at least a first blade section and a second blade section extending in opposite directions from a blade joint, where each blade section comprises a spar section forming a structural member and extending in the longitudinal direction of the blade, and where the first and second blade sections are connected by fastening means restraining any movement of the first blade section relative to the second blade section length ways. The first and the second blade sections are structurally connected by a spar bridge protruding from one of the blade sections and terminating axially in an end portion, which is received in the spar section of the other blade section. The spar bridge and the spar section have interlocking shapes by which rotation of the spar bridge in the spar section is prevented thereby preventing rotation of one of the blade sections relative to the other. Further, the spar section of the other blade section comprises a receiving section extending from the blade joint and inwards into the spar section of that blade, which receiving section holds the spar bridge such that movement of the end portion of the spar bridge relative to the receiving section is enabled in the longitudinal direction. The invention further relates to a method of manufacturing a sectional blade as mentioned above.

First claim

The invention claimed is:

1. A sectional blade for a wind turbine, the blade comprising at least a first blade section and a second blade section extending in opposite directions from a blade joint,
wherein each blade section comprises a spar section forming a structural member of the blade and extending in the longitudinal direction of the blade,
the first and second blade sections being connected by a fastener arranged to restrain movement of the first blade section relative to the second blade section in the longitudinal direction of the blade,
the first blade section and the second blade section being structurally connected by a spar bridge protruding from one of the blade sections and terminating axially in an end portion which is received in the spar section of the other blade section,
the spar bridge and the spar section having interlocking shapes by which rotation of the spar bridge in the spar section is prevented thereby preventing rotation of one of the blade sections relative to the other blade section,
the spar section of the other blade section comprising a receiving section extending from the blade joint and inwards into the spar section of that blade, and
the receiving section holding the spar bridge such that movement of the end portion of the spar bridge relative to the receiving section is enabled in the longitudinal direction.

2. The sectional blade according to claim 1 , wherein the receiving section forms contact with the spar bridge over a first contact section and forms distance to the spar bridge over a second non-contact section.

3. The sectional blade according to claim 1 , wherein the receiving section holds the spar bridge via at least one bearing member.

4. The sectional blade according to claim 3 , wherein at least one bearing member is provided in proximity of an end of the spar bridge.

5. The sectional blade according to claim 3 , wherein said at least one bearing member is provided in proximity to the blade joint.

6. The sectional blade according to claim 3 , wherein the receiving section holds the spar bridge via a number of bearing members provided at intervals inwards into the spar section of that blade.

7. The sectional blade according to claim 3 , wherein said at least one bearing member comprises a liner material formed from one of Ekonol, PTFE, or polyethylene.

8. The sectional blade according to claim 3 , wherein said at least one bearing member comprises an elastic material formed from one of an elastomer, polyurethane, or natural rubber.

9. The sectional blade according to claim 1 , wherein the spar bridge comprises at least one shaft of an oval shaped cross section.

10. The sectional blade according to claim 1 , wherein the spar bridge comprises a tapered portion of decreasing cross sectional area towards an end of the spar bridge.

11. The sectional blade according to claim 1 , wherein the spar bridge comprises at least two substantially aligned shafts.

12. The sectional blade according to claim 11 , further comprising a connection member arranged at least partly between two of said shafts and adapted to take up shear and/or compression forces between the shafts.

13. The sectional blade according to claim 12 , wherein the connection member is positioned lengthways between the blade joint and the end portion of the spar bridge.

14. The sectional blade according to claim 1 , further comprising a spigot extending across the blade joint and arranged to restrain movements in a plane transverse to the longitudinal direction of the blade, and of the trailing edge of the first blade section relative to the trailing edge of the second blade section.

15. The sectional blade according to claim 1 , wherein said fastener comprises a tension member arranged to provide tension in the longitudinal direction of the blade between the first blade section and the second blade section to establish a pre-tensioned connection between the blade sections.

16. The sectional blade according to claim 1 , wherein the spar bridge forms an integral part of the spar section of the first blade section.

17. The sectional blade according to claim 1 , wherein the spar bridge forms a separate member, and each of the spar sections of the first and second blade sections are adapted to receive the spar bridge so as to hold the spar bridge.

18. The sectional blade according to claim 17 , wherein the spar sections of the first and second blade sections both comprise receiving sections extending from the blade joint and inwards into each of the spar sections, the receiving sections both holding the spar bridge such that movement of each end portions of the spar bridge relative to the corresponding receiving section is enabled in the longitudinal direction.

19. The sectional blade according to claim 17 , wherein the spar bridge protruding from the one of the blade sections is bonded into the spar section in said one blade section.

20. The sectional blade section according to claim 1 , wherein the blade joint facilitates disassembling of the blade sections from each other.

21. A method of manufacturing a sectional blade according to claim 1 , the method comprising the steps of:
providing a first blade section and a second blade section;
arranging the blade sections so that they extend in opposite directions from a joint; and
structurally connecting the blade sections by use of a spar bridge.

22. A wind turbine comprising a sectional blade according to claim 1 .

Assignees

• Hibbard Paul
• Hancock Mark
• Vestas Wind Sys As

Inventors

• Hibbard Paul
• Hancock Mark

Classifications

• F05B2240/302

  Segmented or sectional blades · CPC title

• Y10T29/49316

  Impeller making · CPC title

• F03D1/0675 Primary

  of the blades · CPC title

• Y02E10/721

  Cross-Sectional Technologies · mapped topic

• Y02P70/523

  Cross-Sectional Technologies · mapped topic