WIND TURBINE BLADE

• US 20130129518A1
• Filed: 01/03/2013
• Published: 05/23/2013
• Est. Priority Date: 07/08/2010
• Status: Active Grant

• Current Assignee: Blade Dynamics Limited (GE Aerospace)
• Original Assignee: Blade Dynamics Limited (GE Aerospace)
• Inventors: Hayden, Paul Trevor, Behmer, Harald
• Granted Patent: US 8,764,401 B2
• Time in Patent Office: Days
• US Class Current: 416/226
• CPC Class Codes: B29C 70/40 Shaping or impregnating by compression B29C70/34 takes precedencenot applied
• CPC Class Codes: B29C 70/84 by moulding material on preformed parts to be joined joining plastic parts by moulding B29C65/70
• CPC Class Codes: F03D 1/0633 of the blades
• CPC Class Codes: F03D 1/0675 of the blades
• CPC Class Codes: F05B 2240/302 Segmented or sectional blades
• CPC Class Codes: Y02E 10/72 Wind turbines with rotation axis in wind direction
• CPC Class Codes: Y10T 29/49339 Hollow blade

Abstract

A wind turbine blade comprising an aerodynamic fairing supported along at least a portion of its axial length by a spar (12). The spar comprises at least two spar segments (12) joined end-to-end at an interface (9), each spar segment comprising a shear web (3) with a spar cap (4) on each side. The outer face (6) of each spar cap tapers inwardly towards the interface such that its depth is reduced towards the interface creating a recess on each side of the interface formed by the tapered faces of adjacent spar caps. A respective connection piece (8) is sized to fit into each recess. Each connection piece (8) is sized to fit into each recess. Each connection piece (8) being fixed to the tapered faces of adjacent spar caps to form a double scarf joint.

Claims

1. A wind turbine blade comprising an aerodynamic fairing supported along at least a portion of its axial length by a spar, the spar comprising at least two spar segments joined end-to-end at an interface, each spar segment comprising a shear web with a spar cap on each side;

wherein the outer face of each spar cap tapers inwardly towards the interface such that its depth is reduced towards the interface creating a recess on each side of the interface formed by the tapered faces of adjacent spar caps; and

a respective connection piece sized to fit into each recess, each connection piece being fixed to the tapered faces of adjacent spar caps to form a double scarf joint.

2. A blade according to claim 1, wherein the end of each shear web is substantially perpendicular to the axial direction such that the ends of the shear webs support one another.

3. A blade according to claim 1, wherein there is no double scarf joint between the shear webs.

4. A blade according to claim 1, wherein the connection piece is bonded to the tapered faces of adjacent spar caps.

5. A blade according to claim 4, wherein the connection piece is a pre-cured component.

6. A blade according to claim 1, wherein the connection piece is formed in situ from a plurality of laminations.

7. A blade according to claim 1, wherein the shear webs of adjacent spar segments are connected together.

8. A blade according to claim 7, wherein the shear webs of adjacent spar segments are bonded together with adhesive.

9. A blade according to claim 1, further comprising a support member which receives and aligns the shear webs relatively to one another.

10. A blade according to claim 6, wherein adjacent spar segments are bonded together with adhesive that is applied to the support member.

11. A method of making a blade according to claim 1 comprising the steps of inserting spar caps of adjacent segments into a U-shaped channel with their tapered surface uppermost;

and fitting the connection piece to the tapered surfaces of the adjacent spar caps.

12. A method according to claim 11, further comprising subsequently joining additional spar caps with additional connection pieces to the subassembly formed by the method of claim 11.

13. A method according to claim 12, further comprising repeating the steps of claim 12 to form a second spar cap, joining the two spar caps with at least one shear web to form a first spar beam.

14. A method according to claim 13, further comprising repeating the steps of claim 11 to form a second spar beam and joining the first and second beams side by side to form a spar.

15. A method according to claim 11, where the U-shaped channel is the channel used to form the spar caps.