Vertical axis windmill and self-erecting structure therefor

1. A wind system of the type having a rotating shaft perpendicular to the ground, comprising:

a plurality of blades positioned in a pre-strained rigid configuration as the wind system is at rest;

a top set of horizontal tensioned wing-beams, said top set of horizontal tensioned wing-beams having a triangular configuration and connecting the blades to a top end of the rotating shaft; and

a bottom set of horizontal tensioned wing-beams, said bottom set of horizontal tensioned wing-beams having a triangular configuration and connecting the blades to a bottom end of the rotating shaft;

wherein said blades and sets of horizontal tensioned wing-beams form a flexible blade attachment assembly, which tends to get flattened under a centrifugal force and adopts a troposkein shape at a target speed of rotation, said troposkein shape being then maintained by the sets of horizontal tensioned wing-beams.

2. The wind system according to claim 1 , further comprising a top set of securing elements having a triangular configuration and a bottom set of securing elements having a triangular configuration respectively securing the blades to the rotating shaft.

3. The wind system according to claim 1 , wherein each one of said plurality of blades comprises a stress-absorbing member inserted into a sheathing.

4. The wind system according to claim 3 , wherein said sheathing is aerodynamically profiled.

5. The wind system according to claim 3 , said stress-absorbing member is a leaf spring.

6. The wind system according to claim 3 , said sheathing is directly molding onto said stress-absorbing member.

7. The wind system according to claim 3 , said sheathing is made of a material that can be easily attached around said stress-absorbing member.

8. The wind system according to claim 3 , wherein said sheathing is made of a material selected in the group comprising rubber and fiberglass.

9. The wind system according to claim 3 , wherein said stress-absorbing member is pre-shaped to a generally troposkein geometry.

10. The wind system according to claim 9 , further comprising a generator assembly to produce electricity.

11. The wind system according to claim 10 , wherein said generator assembly comprises a generator connected to a rotation increasing device, said rotation increasing device having a driven shaft mounted to the rotating shaft of the wind system.

12. The wind system according to claim 11 , wherein said rotation increasing device is a cycloid speed-increasing gear.

13. The wind system according to claim 12 , further comprising an enclosure provided with a base and a top, and enclosing said generator.

14. The wind system according to claim 10 , wherein said generator assembly comprises a stator and a rotating casing supported by a stationary base.

15. The wind system according to claim 14 , wherein said rotating casing is connected to the rotating shaft by securing elements.

16. The wind system according to claim 14 , wherein said rotating casing supports a cover.

17. The wind system according to claim 14 , wherein said rotating shaft is shorter than at least one of the blades and the wing beams.

18. The wind system according to claim 1 , wherein said wind system is a vertical axis windmill.

19. The wind system according to claim 1 , provided with a structure comprising a lower portion; a middle portion, which can telescope in said lower portion; and a top portion holding the rotating shaft, which can telescope in said middle portion.

20. The wind system according to claim 19 , wherein said structure further comprises removable hydraulic jacks, each provided with an erecting cable having a mobile end connected to a base of a portion to be erected, and a stationary end attached to a base of a corresponding jack.

21. A blade attachment structure for a windmill, comprising blades connected to a rotating shaft by wing-beams arranged in sets of horizontal wing-beams under tension, said sets of horizontal wing-beams under tension having a triangular configuration and holding a spatial distribution of the blades, and by sets of securing elements, said sets of securing elements having a triangular configuration and being mounted respectively to each sets of horizontal wing-beams, wherein said blades are positioned in a pre-strained rigid configuration as the windmill is at rest.

22. The blade attachment structure according to claim 21 , wherein said sets of horizontal wing-beams comprise a first set of honzontal wing-beams and a second set of horizontal wing-beams and said sets of securing elements comprise a first set of securing elements securing the first set of horizontal wing-beams on top of the blade attachment structure and a second set of securing elements securing the second set of horizontal wing-beams at the bottom of the blade attachment structure.

23. The blade attachment structure according to claim 21 , comprising three (3) blades.

24. The blade attachment structure according to claim 21 , wherein said rotating shaft is shorter than at least one of the blades and the wing beams

25. The blade attachment structure according to claim 21 , having at all times a troposkein geometry.

26. A blade attachment structure for a windmill comprising blades mounted to a driving shaft by means of tensioning means and positioned in a pre-strained rigid configuration as the windmill is at rest, said blades being connected in a spatial distribution to at least one set of horizontal wing-beams under tension, said at least one set of horizontal wing-beams having a triangular configuration by said at least one set of securing elements, said at least one set of securing elements having a triangular configuration, in such a way as to form a flexible assembly, which tends to get flattened under a centrifugal force and adopts a troposkein shape at a target speed of rotation, said troposkein shape being maintained by the tensioning means.

27. A generator assembly for the windmill according to claim 1 , comprising a generator connected to a rotation-increasing device, said rotation-increasing device having a driven shaft mounted to a rotating shaft of the windmill.

28. The generator assembly according to claim 27 wherein said rotation increasing device is a cycloid speed-increasing gear.

29. The generator assembly according to claim 27 , further comprising an enclosure provided with a base and a top, for enclosing said generator.

30. A generator assembly for the windmill according to claim 1 , comprising a rotating casing supported by a stationary base through steady bearings, brake shoes, and a stator, wherein said rotating casing is connected to a rotating shaft of the windmill.

31. A self erecting structure for the windmill according to claim 1 , comprising a lower portion, a middle portion able to telescope in said lower portion, and a top portion in the form of a stationary enclosure holding a rotating shaft of the windmill and able to telescope in said middle portion.

32. The self erecting structure according to claim 31 , wherein a first, a second and a third hydraulic jack, each having an erecting cable with a mobile end connected to a base of the windmill to be erected, and a stationary end attached to a base of the first, second and a third hydraulic jack respectively.

33. The self erecting structure according to claim 31 , wherein said erecting cable of the first hydraulic jack passes through a pulley of said first hydraulic jack and has a stationary end attached to the base of said first hydraulic jack; said erecting cable of the second hydraulic jack passes through a pulley of said second hydraulic jack and has a stationary end attached to the base of said second hydraulic jack; said erecting cable of the third hydraulic jack passes through a pulley of said third hydraulic jack and has a stationary end attached to the base said third hydraulic jack.

34. The self erecting structure according to claim 31 , wherein a first and a second removable hydraulic jacks are mounted by a respective base thereof on a base of said lower portion, and a third removable hydraulic jack is mounted on a base of said middle portion, said first, second and third removable hydraulic jacks being each provided with a piston rod, each piston rod being provided with a pulley at a distal end thereof respectively.

35. A method for erecting the windmill according to claim 1 , said windmill being made of a plurality of telescoping portions, from a lying position comprising successively lifting the telescoping portions to a fully extended position thereof.