Device for assembling sections of wind-turbine blades and method for linking sections of wind-turbine blades

1. A device for assembling sections of wind turbine blades provided with composite casings, including at least one tie comprising a first portion and a second portion, the first portion being a portion for assembly with a casing of a first section and the second portion being a portion for mounting with a complementary tie supported by a casing of a second section, wherein the first portion includes at least one composite/metal shear link provided with a continuous metallic fitting element on at least one flat side of the casing, said fitting element receiving one end of said flat side of the casing, provided with several rows and lines of attachment pins passing through the fitting and the end of the flat side, wherein the composite/metal link has at least double shear and is additionally provided with back-fitting element, the end of said flat side of the casing being received between the fitting and the back fitting element, the rows and lines of attachment pins passing through the fitting, the end of the flat side and the back fitting element, the back fitting being attached to casing and the fitting.

2. A device for assembling sections of wind turbine blades according to claim 1 , wherein the composite/metal link is a multi-shear link perpendicular to the attachments and comprises into the composite material a metallic doubler adapted to carry forces between the composite portion and said metallic fitting element.

3. A wind turbine blade comprising at least two sections, each provided with a casing wherein the sections are assembled by means of a pair of assembly devices according to claim 1 .

4. A wind turbine blade according to claim 3 , wherein an end of said side terminates with a reinforced monolithic structure.

5. A wind turbine blade according to claim 4 , wherein the reinforced monolithic structure is essentially reinforced by carbon layers.

6. A wind turbine blade according to claim 4 , wherein said central casing comprises a composite structure progressively replaced by the reinforced monolithic structure at the terminal point of the section.

7. A wind turbine blade according to claim 3 , wherein said composite/metal link comprises a local reinforcing element for the end of the casing surface in the form of composite plies.

8. A wind turbine blade according to claim 3 , wherein the fitting element is comprised from a continuous, closed frame supporting surfaces and fins of the end of the casing.

9. A wind turbine blade according to claim 3 , wherein said blade comprises two of said ties, the assembly portions of which are constituted from a plate supporting one side of an end of the casing.

10. A wind turbine blade according to claim 9 , wherein said ties are positioned on an upper-flat side and a lower flat side of the casings located underneath an upper surface and a lower surface of the section of the blade.

11. A wind turbine blade according to claim 10 , wherein ends of the sides of the casing, located between the upper surface and the lower surface, receive connecting squares.

12. A wind turbine blade according to claim 3 , wherein the ends of the casing surfaces comprise a terminal point with a skin to skin terminal.

13. A wind turbine blade according claim 12 , wherein the ends of the casing surfaces comprise a terminal point with reinforcement of the skin to skin terminal.

14. A wind turbine blade according to claim 3 , wherein ends of the casing surfaces comprise a terminal point with the filling of a honeycomb and/or a densified honeycomb.

15. A wind turbine blade according to claim 3 , wherein the portions for mounting the ties with the complementary ties comprise surfaces adapted for attachment by axial link using tensile bolt means.

16. A wind turbine blade according to claim 3 , wherein the ties are positioned within the aerodynamic profile of the blade.