US3763811A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flexing hydrofoil
Assignee: Individual
•
Filing: 1972-08-03
•
Granted: 1973-10-09
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Expires: 1992-08-03
Abstract
Abstract This specification discloses a flexing hydrofoil that consists essentially of a thin flexible blade that is secured to the underside of a boat hull transversely thereof and in spaced relation thereto by three or more struts together with tensioning cables connected to the ends of the blade. Provision may also be made for the blade to be moved into engagement with the hull when the hydrofoil is to be ineffective. The present invention relates to hydrofoils that are mounted on a boat hull and is concerned primarily with a flexing hydrofoil that includes as a characteristic and essential element a flexing blade.
Inventors
- 👤 P Danahy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 01:07
CPC Classifications
B; B63; B63B; B63B1/00; B63B1/16; B63B1/24; B63B1/28; B63B1/30
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
168 words
For use with a boat hull having a bottom and sides, a hydrofoil comprising: a. a thin flexible metallic blade having a leading edge, a trailing edge and end edges; b. a center strut having an upper end in engagement with said bottom centrally thereof and a lower end engaging said blade; c. a pair of outboard struts each having an upper end portion secured to one of said sides and a lower end engaging said blade; d. two pairs of cables, one pair at each side of said hull, a cable of each pair being connected to one end of said blade adjacent to said leading edge with the other cable of that pair being connected to said blade end adjacent to said trailing edge, and e. means for applying various degrees of tension to said cables to cause said blade to flex between port and starboard ends in different amounts from said leading to trailing edges and thereby vary the angle of attack of said blade.
Claim 2
Dependent Claim
168 words
For use with a boat hull having a bottom and sides, a hydrofoil comprising: a. a thin flexible metallic blade having a leading edge, a trailing edge and end edges; b. a center strut having an upper end in engagement with said bottom centrally thereof and a lower end engaging said blade; c. a pair of outboard struts each having an upper end portion secured to one of said sides and a lower end engaging said blade; d. two pairs of cables, one pair at each side of said hull, a cable of each pair being connected to one end of said blade adjacent to said leading edge with the other cable of that pair being connected to said blade end adjacent to said trailing edge, and e. means for applying various degrees of tension to said cables to cause said blade to flex between port and starboard ends in different amounts from said leading to trailing edges and thereby vary the angle of attack of said blade.
Claim 3
Dependent Claim
29 words
The hydrofoil of claim 1 together with guide means for said cable on the hull sides and in which said tensioning means includes energy absorbing devices on said hull.
Claim 4
Dependent Claim
12 words
The hydrofoil of claim 2 together with devices for controlling the tension.
Claim 5
Dependent Claim
36 words
The hydrofoil of claim 2 in which said guide means comprises outwardly extending flanges on the upper ends of said outboard struts and tongues extending outwardly of said hull from the tops of the sides thereof.
Claim 6
Dependent Claim
33 words
The hydrofoil of claim 4 in which said flanges are formed with holes through which said cables pass, and pulleys are carried by said flanges at said holes over which said cables ride.
Claim 7
Dependent Claim
14 words
The hydrofoil of claim 1 in which said blade is removable from said hull.
Claim 8
Dependent Claim
14 words
The hydrofoil of claim 6 in which said struts are removable from said hull.
Claim 9
Dependent Claim
14 words
The hydrofoil of claim 1 in which said blade is of a laminated construction.
Claim 10
Dependent Claim
49 words
The hydrofoil of claim 1 in which said struts are hingedly connected at their upper ends to the bottom and sides respectively, the lower end of the center strut is fixedly secured to said blade and the lower ends of the outboard struts are slidably connected to said blade.
Claim 11
Dependent Claim
32 words
The hydrofoil of claim 9 in which the slidable connections are provided by nacelles at the lower ends of said outboard struts with the nacelles having slots through which said blade passes.
Claim 12
Dependent Claim
24 words
The hydrofoil of claim 1 in which the blade is collapsible into a position in which it substantially engages the bottom of the hull.
Claim 13
Dependent Claim
22 words
The hydrofoil of claim 1 in which the outboard struts bend and/or twist elastically thereby altering the tension within the foil blade.
References Cited (Backward Citations)
FR679106A
Cited
US2991747A
Cited
US3150626A
Cited
US3184187A
Cited
US3199484A
Cited
US3345968A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-08 | 1977-04-09 | 1977-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-08 | 1981-04-09 | 1981-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-08 | 1985-04-09 | 1985-10-09 | $7700.00 | Window Closed / Lapsed |