Pliant mechanisms for extracting power from moving fluid

• US 7,696,634 B2
• Filed: 09/30/2008
• Issued: 04/13/2010
• Est. Priority Date: 05/01/2007
• Status: Active Grant

• Current Assignee: Pliant Energy Systems LLC
• Original Assignee: Pliant Energy Systems LLC
• Inventors: Filardo, Benjamin Pietro
• Primary Examiner(s): Ponomarenko; Nicholas
• Application Number:
  US12/242,144
• Publication Number:
  US 20100045036A1
• Time in Patent Office: 560 Days
• Field of Search: 290/42, 290/43, 290/44, 290/53, 290/54, 416/1, 416/189
• US Class Current: 290/54
• CPC Class Codes: F03B 17/06 using liquid flow with predominantly kinetic energy conversion, e.g. of swinging-flap type , "run-of-river", "ultra-low head" F03B13/264 takes precedence
• CPC Class Codes: F05B 2240/311 flexible or elastic
• CPC Class Codes: H02N 2/185 using fluid streams
• CPC Class Codes: Y02E 10/20 Hydro energy
• CPC Class Codes: Y02E 10/30 Energy from the sea, e.g. using wave energy or salinity gradient

Abstract

Flexible and elastic mechanisms for extracting power from a moving fluid. Sheet-like material is deformed during fabrication through an applied force so as to create undulations in said material, whose stresses are maintained through restraining components, thereby maintaining the occurrence of said deformations in the material. When placed in moving fluid, the resulting pressure differentials cause the positions of the undulations within the material to travel along said material in the same direction as the moving fluid. Power is extracted in one of two principle ways. The first is via a mechanical coupling of the sheet-like material to a rotating mechanism, which turns an electro-magnetic dynamo or other output device. The second is via the utilization of a flexible material which exhibits an electrical response to mechanical strain, whereby the strains caused by the travel of undulations along the material create an electrical current which is extracted via two or more electrodes.

Claims

1. A power generator for extracting power from fluid motion, said power generator having a structure adapted to be disposed in a flowing fluid which comprises, in combination:

a. a plurality of restraining components;

b. a plurality of fronds for converting fluid motion into power, each of said fronds having a longitudinal axis, being made of a flexible sheet material and being attached to at least one of said restraining components to maintain said material in a deformed state under continuous internal stress by securing different sections of said fronds, said material being configured in the deformed state so as to create wave-shaped undulations in the respective frond, such that, when the fronds are subjected to the forces of a moving fluid directed along their longitudinal axes, the positions of the undulations in said fronds move in unison and in the direction of the moving fluid; and

c. a device for extracting power from undulations of said fronds.

2. The power generator defined in claim 1, wherein said restraining components and said fronds are arranged to hold the plurality of fronds in a prescribed pattern, when viewed in a plane perpendicular to the direction of the moving fluid, said pattern being selected from the group consisting of an array, an asterisk, a polygonal ring, and a honeycomb.

3. The power generator defined in claim 1, wherein the flexible material is elastic.

4. The power generator defined in claim 1, wherein the flowing fluid is selected from the group consisting of air and water.

5. The power generator defined in claim 1, wherein undulations form traveling waves in the fronds.

6. The power generator defined in claim 1, wherein one or more of the fronds form electrical transducers for converting mechanical motion into-electrical energy, wherein the undulations of such fronds create a voltage potential therein and wherein said power extracting device includes at least two electrodes, coupled to such fronds, for extracting electrical power from such fronds.

7. The power generator defined in claim 1, wherein the power extracting device is at least one mechanical component, configured for movement by the undulations of said fronds.

8. The power generator defined in claim 7, wherein said power extracting device includes a drive shaft mounted for rotation about a longitudinal axis and at least one mechanical device configured to translate the undulations of said fronds into rotational movement of said shaft about its axis.

9. The power generator defined in claim 8, wherein said mechanical device includes at least one ratchet mechanism for rotating said shaft in one direction in response to the undulations of said fronds.

10. The power generator defined in claim 8, wherein said at least one ratchet mechanism includes a plurality of ratchet mechanisms configured to continuously rotate said shaft in said one direction.

11. The power generator defined in claim 1, wherein pairs of said fronds are further mechanically coupled to each other along a common longitudinal edge such that they undulate in unison.

12. The power generator defined in claim 1, wherein said restraining components and said fronds are arranged in an array of one or more parallel frond lines, each of said frond lines comprises at least two of said fronds mechanically coupled to each other along a common longitudinal edge, such that said frond lines undulate in unison.

13. The power generator defined in claim 12, wherein undulations of each frond in a frond line from said frond lines are out-of-phase with undulations of adjacent fronds in the frond line.

14. The power generator defined in claim 2, wherein the pattern of arrangement of said restraining components and said fronds is in the shape of an asterisk, and wherein an inner longitudinal edge of each of said fronds is mechanically coupled to a first restraining component from said restraining components, an outer longitudinal edge of each of said fronds is mechanically coupled to at least a second restraining component from said restraining components, such that undulations of said fronds are in-phase.

15. The power generator defined in claim 14, wherein mechanical coupling of inner longitudinal edges of said fronds to the first restraining component forms a polygonal cross-section, mechanical couplings of outer longitudinal edges of said fronds to the second restraining component form V-shaped cross-sections.

16. The power generator defined in claim 15, wherein the polygonal cross-section is closed by a plurality of plates stacked along a longitudinal axis, the first restraining component is a hollow tube passing through the plurality of plates along the longitudinal axis.

17. The power generator defined in claim 15, wherein the V-shaped cross-sections are closed.

18. The power generator defined in claim 14, wherein the second restraining component comprises at least one of (a) rigid members attached to radial rings and (b) a tube covering said fronds.

19. The power generator defined in claim 2, wherein the pattern of arrangement of said restraining components and said fronds is in the shape of a polygonal ring, and wherein pairs of said fronds are mechanically coupled to each other along a common longitudinal edge, said fronds being surrounded by a third restraining component from said restraining components.

20. The power generator defined in claim 19, wherein undulations of each of said fronds are out-of-phase with undulations of adjacent fronds.

21. The power generator defined in claim 19, wherein the third restraining component is a polygonal outer-casing.

22. The power generator defined in claim 19, wherein junctions of two adjacent fronds from said fronds and the third restraining component form channels having triangular cross-sections.

23. The power generator defined in claim 21, wherein each of said channels is closed by a plurality of plates stacked along a longitudinal axis, and said restraining components comprise a plurality of hollow tubes passing through the plurality of plates of each of said channels along the longitudinal axis.

24. The power generator defined in claim 19, wherein the polygonal ring is restrained by a fourth restraining component from said restraining components, such that the polygonal ring surrounds the fourth restraining component, and the fourth restraining component comprises a closed polygonal tube.

25. The power generator defined in claim 2, wherein the pattern of arrangement of said restraining components and said fronds is in the shape of a honeycomb, said honeycomb comprising a plurality of polygonal rings parallel to each other, wherein each of said polygonal rings comprises more than two fronds from said fronds mechanically coupled to each other along longitudinal edges of each of the more than two fronds, and wherein the honeycomb is restrained by an additional restraining component from said restraining components.

26. The power generator defined in claim 25, wherein undulations of each of the more than two fronds are out-of-phase with undulations of adjacent fronds.

27. The power generator defined in claim 25, wherein undulations of each of the more than two fronds are in-phase with undulations of adjacent fronds.

28. The power generator defined in claim 25, wherein each of said polygonal rings is out-of-phase with adjacent polygonal rings.

29. The power generator defined in claim 25, wherein the additional restraining component is a polygonal outer-casing.

30. The power generator defined in claim 25, wherein junctions of more than two polygonal rings form channels having triangular cross-sections.

31. The power generator defined in claim 30, wherein each of said channels is closed by a plurality of plates stacked along a longitudinal axis, and said restraining components comprise a plurality of hollow tubes passing through the plurality of plates of each of said channels along the longitudinal axis.

32. The power generator defined in claim 31, further comprising:

at least one axle situated within and substantially concentric with one of the plurality of hollow tubes and ratchetedly coupled to a corresponding subset of the plurality of plates.

33. The power generator defined in claim 25, wherein junctions of more than three polygonal rings from channels having square cross-sections.

34. The power generator defined in claim 25, wherein one or more polygonal rings from said polygonal rings are restrained by one or more sixth restraining components from said restraining components, such that each of the one or more polygonal rings is surrounded by a corresponding sixth restraining component from said one or more sixth restraining components.

35. The power generator defined in claim 34, wherein said one or more sixth restraining components are closed polygonal tubes.

36. The power generator defined in claim 34, wherein one or more polygonal rings from said polygonal rings are additionally restrained by one or more seventh restraining components from said restraining components, such that each of the one or more polygonal rings surrounds a corresponding seventh restraining component from said one or more seventh restraining components.

37. The power generator defined in claim 36, wherein said one or more seventh restraining components are closed polygonal tubes.

38. The power generator defined in claim 25, wherein said polygonal rings comprise polygonal rings having different shapes and sizes.