Vertical axis wind turbine system

• US 20080145224A1
• Filed: 08/09/2007
• Published: 06/19/2008
• Est. Priority Date: 08/09/2006
• Status: Active Grant

• Current Assignee: Sri Vawt, Inc.
• Original Assignee: Sri Vawt, Inc.
• Inventors: Detenbeck, Michael James, Scott, George Arthur, Mitchell, John Sinclair
• Granted Patent: US 7,896,609 B2
• Time in Patent Office: Days
• US Class Current: 416/132B
• CPC Class Codes: F03D 3/005 the axis being vertical
• CPC Class Codes: F03D 7/06 the wind motors having rotation axis substantially perpendicular to the air flow entering the rotor
• CPC Class Codes: F05B 2240/212 of the Darrieus type
• CPC Class Codes: F05B 2240/311 flexible or elastic
• CPC Class Codes: F05B 2240/313 with adjustable flow intercepting area F05B2240/312 takes precedence
• CPC Class Codes: Y02E 10/74 Wind turbines with rotation axis perpendicular to the wind direction

Abstract

The present invention is a vertical wind turbine having a turbine with a plurality of blades or wind vanes. The blades are constructed and attached to the shaft of the turbine so as to allow them to twist open to present more surface area to wind currents when a threshold rotational velocity is reached. Also presented are a novel outer shell that is placed over at least part of the shaft and a novel turbine blade.

Claims

1. A wind turbine system comprising:

a base, said base standing in a substantially vertical orientation in relation to a foundation or ground and having a bottom end and a top end;

a rotating shaft extending from said top end of said base in a substantially vertical orientation;

a lower shaft attachment means attached to said shaft;

an upper shaft attachment means attached to said shaft above said lower attachment means;

a turbine comprising a plurality of blades, each of said blades formed from a curved 27-2012 airfoil and having a first end fabricated from a rubber or elastomer and attached to said upper shaft attachment means and a second end fabricated from elastomer or rubber and attached to said lower shaft attachment means, wherein each of said first ends is attached to said upper shaft attachment means by a swivel connection and each of said second ends is fixedly attached to said lower shaft attachment means using a plurality of bolts;

wherein said second end is curved toward said first end to form a peak wherein the length of said airfoil from said peak to said second end is less than the length of said airfoil from said peak to said first end; and

,

wherein the angle between said peak and said second end is more acute than the angle between said peak and said first end; and

,

wherein each of said vanes twists on said swivel connection when rotating at a velocity above a first threshold velocity.

2. The wind turbine system as recited in claim 1 further comprising an outer shell surrounding said shaft and extending at least between said upper attachment means and said lower attachment means.

3. The wind turbine system as recited in claim 2 wherein said outer shell possesses a diameter at least 20 percent of the diameter of said turbine.

4. The wind turbine system as recited in claim 2, wherein said outer shell is rotated using at least one motor.

5. The wind turbine system as recited in claim 1 wherein at least part of the outer surface of said rotating shaft extending below said turbine includes a plurality of facings.

6. The wind turbine system as recited in claim 5, where each of said plurality of facings has a central depression and helical-shaped edges wherein said central depression and said helical-shaped edges extend the longitudinal length of said facing.

7. The wind turbine system as recited in claim 5 wherein said plurality of facings comprises three facings.

8. The wind turbine system as recited in claim 1 wherein said shaft possesses a diameter at least 20 percent of the diameter of said turbine.

9. The wind turbine system as recited in claim 1 wherein said lower attachment is a hub surrounding said shaft and comprises a plurality of receivers to receive said second end of one of said plurality of said blades, each of said receivers including a plurality of nut and bolt assemblies to attach said second end to said receiver.

10. The wind turbine system as recited in claim 9 wherein each of said plurality of nut and bolt assemblies comprises four nut and bolt assemblies.

11. The wind turbine system as recited in claim 1 wherein said upper assembly is a hub having a plurality of receivers to receive said first end of one of said blades, said receiver including said swivel connection.

12. The wind turbine system as recited in claim 1 wherein said swivel connection comprises a bolt and a castle nut.

13. The wind turbine system as recited in claim 1 wherein at least one of said blades is fabricated from a composite material.

14. The wind turbine system as recited in claim 1 wherein at least one of said blades is fabricated from metal.

15. The wind turbine system as recited in claim 1 wherein at least one of said blades is fabricated from wood.

16. The wind turbine system as recited in claim 1 wherein said plurality of blades comprises an odd number of blades.

17. The wind turbine system as recited in claim 16 wherein said plurality of blades comprises five blades.

18. The wind turbine system as recited in claim 1 further comprising a generator, said generator operatively attached to said rotating shaft.

19. The wind turbine system as recited in claim 1 wherein said base is a tower.

20. A wind turbine system comprising:

a base, said base standing in a substantially vertical orientation in relation to a foundation or ground and having a bottom end and a top end;

a rotating shaft extending from said top end of said base in a substantially vertical orientation;

an extension of said rotating shaft, wherein said extension extends above said turbine and includes a plurality of facings on the outer surface of said extension, each of said plurality of facings having a central depression and helical-shaped edges wherein said central depression and said helical-shaped edges extend the longitudinal length of said facing;

a lower shaft attachment means attached to said shaft;

an upper shaft attachment means attached to said shaft above said lower attachment means;

a turbine comprising a plurality of blades, each of said blades formed from a curved 27-2012 airfoil and having a first end fabricated from a rubber or elastomer and attached to said upper shaft attachment means and a second end fabricated from elastomer or rubber and attached to said lower shaft attachment means, wherein each of said first ends is attached to said upper shaft attachment means by a swivel connection and each of said second ends is fixedly attached to said lower shaft attachment means using a plurality of bolts;

wherein said second end is curved toward said first end to form a peak wherein the length of said airfoil from said peak to said second end is less than the length of said airfoil from said peak to said first end;

wherein the angle between said peak and said second end is more acute than the angle between said peak and said first end;

wherein each of said vanes twists on said swivel connection when rotating at a velocity above a first threshold velocity; and

,

wherein said rotating shaft includes a modified portion, said modified portion extending below said turbine and including a plurality of facings has a central depression and helical-shaped edges wherein said central depression and said helical-shaped edges extend the longitudinal length of said facing.

21. A modified 27-2012 airfoil comprising:

a tapered first end having an endpiece, said end piece being flexible to allow twisting of said airfoil; and

,

a tapered second end, said tapered second end having an endpiece;

wherein said second end is curved toward said first end to form a peak, and;

wherein the length from said peak to said second end is less than the length from said peak to said first end; and

,

wherein said that angle between said peak and said second end is more acute than the angle between said peak and said first end.

22. The flexible blade for a vertical axis wind turbine as recited in claim 21 wherein said airfoil is a composite comprising:

an outer skin fabricated from a fabric material; and

,

an inner core fabricated from a combination of foam and fiberglass material.

23. The flexible blade for a vertical axis wind turbine as recited in claim 22 wherein said composite is vacuum injection molded.

24. The flexible blade for a vertical axis wind turbine as recited in claim 22 wherein said fabric material is KEVLAR®

.

25. The flexible blade for a vertical axis wind turbine as recited in claim 22 wherein said fabric material is formed from carbon graphite.

26. The flexible blade for a vertical axis wind turbine as recited in claim 21 wherein said first end of said flexible blade includes a rubber or elastomer.

27. The flexible blade for a vertical axis wind turbine as recited in claim 22 wherein said foam is polyurethane.

28. The flexible blade for a vertical axis wind turbine as recited in claim 22 wherein said fiberglass is formed from vinyl ester.