US3804048A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydrofoil watercraft
Assignee: DYNAFOIL
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Filing: 1973-03-15
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Granted: 1974-04-16
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Expires: 1993-03-15
Abstract
Abstract A hydrofoil watercraft utilizing forward and rearward struts and foils configured and oriented to provide lateral stability. The forward strut is freely rotatable about its longitudinal axis and mounts the forward foils. The strut and foils are configured and oriented such that the resultant of the lift, pressure, and drag forces therein tends to stabilize the watercraft in a turn and generate righting forces.
Inventors
- 👤 D Cline
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 19:38
CPC Classifications
B; B63; B63B; B63B1/00; B63B1/16; B63B1/24; B63B1/28; B63B1/283
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
182 words
A hydrofoil watercraft comprising: an elongated hull having a longitudinal center gravity axis; propulsion means for driving said hull; forward strut means mounted to the forward portion of said hull for rotation about a support axis extending downwardly and forwardly relative to said center of gravity axis, said forward strut means being characterized by side surfaces having a center of pressure located rearwardly of said support axis whereby, upon tipping of said watercraft to one side during propulsion thereof, water pressure acting upon said forward strut means tends to turn said forward strut means in the direction of said one side; non-surface piercing forward hydrofoil means carried by said forward strut means and characterized by surfaces operative to develop lift forces collectively acting upwardly along a lift axis which intersects said support axis below said center of gravity axis whereby turning of said forward strut means tends to develop a righting force tending to move the watercraft to an upright position; rearward strut means mounted to the rearward portion of said hull; and rearward hydrofoil means carried by said rearward strut means.
Claim 2
Dependent Claim
182 words
A hydrofoil watercraft comprising: an elongated hull having a longitudinal center gravity axis; propulsion means for driving said hull; forward strut means mounted to the forward portion of said hull for rotation about a support axis extending downwardly and forwardly relative to said center of gravity axis, said forward strut means being characterized by side surfaces having a center of pressure located rearwardly of said support axis whereby, upon tipping of said watercraft to one side during propulsion thereof, water pressure acting upon said forward strut means tends to turn said forward strut means in the direction of said one side; non-surface piercing forward hydrofoil means carried by said forward strut means and characterized by surfaces operative to develop lift forces collectively acting upwardly along a lift axis which intersects said support axis below said center of gravity axis whereby turning of said forward strut means tends to develop a righting force tending to move the watercraft to an upright position; rearward strut means mounted to the rearward portion of said hull; and rearward hydrofoil means carried by said rearward strut means.
Claim 3
Dependent Claim
29 words
A hydrofoil watercraft according to claim 1 and including steering means coupled to said forward strut means and operable to rotate said forward strut means about said support axis.
Claim 4
Dependent Claim
39 words
A hydrofoil watercraft according to claim 1 wherein said side surfaces of said forward strut means are generally vertically oriented, and said forward hydrofoil means comprise a pair of laterally extending foils disposed substantially normal to said side surfaces.
Claim 5
Dependent Claim
31 words
A hydrofoil watercraft according to claim 3 wherein said foils are each generally delta-shaped in configuration whereby the effective impact of foreign objects against the raked leading edge thereof is lessened.
Claim 6
Dependent Claim
30 words
A hydrofoil watercraft according to claim 1 wherein said rearward hydrofoil means comprise a pair of anhedral foils extending laterally and downwardly from opposite sides of said rearward strut means.
Claim 7
Dependent Claim
46 words
A hydrofoil watercraft according to claim 1 wherein said forward and rearward strut means each comprise a depending fin-like strut having generally vertically disposed sides, the rear said strut lying generally in the plane which includes said longitudinal axis of said hull and said support axis.
Claim 8
Dependent Claim
16 words
A hydrofoil watercraft according to claim 6 wherein said struts each include a blunt trailing edge.
Claim 9
Dependent Claim
32 words
A hydrofoil watercraft according to claim 1 wherein said rearward hydrofoil means comprise a pair of foils on opposite sides of said rearward strut means and oriented to define an inverted V-shape.
Claim 10
Dependent Claim
49 words
A hydrofoil watercraft according to claim 1 wherein said forward hydrofoil means comprise a pair of dElta-shaped foils extending laterally of said forward strut means, the chord line of each of said foils being shorter at its outer portion than at its inner portion adjacent said forward strut means.
Claim 11
Dependent Claim
25 words
A hydrofoil watercraft according to claim 1 wherein at least a portion of said rearward hydrofoil means is movable to aid in turning the watercraft.
Claim 12
Dependent Claim
44 words
A hydrofoil watercraft according to claim 1 wherein said rearward hydrofoil means comprise a pair of laterally extending foils each of which includes an aileron portion; and including steering means operative to oppositely move the aileron portions and thereby aid in turning the watercraft.
Claim 13
Dependent Claim
34 words
A hydrofoil watercraft according to claim 11 and including means coupling said steering means and said forward strut means whereby rotation of said forward strut means is accompanied by movement of said aileron portions.
Claim 14
Dependent Claim
34 words
A hydrofoil watercraft according to claim 1 wherein said hull includes upper and lower substantially V-shaped hull portions, said lower hull portion having a deeper and narrower V-shape section than said upper hull portion.
Claim 15
Dependent Claim
171 words
A hydrofoil watercraft comprising: an elongated hull adapted for propulsion through water; forward strut means mounted to the forward portion of said hull and including a generally flat-sided, vertically oriented forward strut rotatable about a support axis extending downwardly and forwardly relative to the longitudinal axis of said hull, a greater portion of the side surface area of said forward strut being located rearwardly of said support axis whereby upon tipping of said watercraft to one side during propulsion thereof water pressure acting upon said side surface area of said forward strut tends to turn said forward strut means in the direction of said one side; forward hydrofoil means of the fully submerged type carried by said forward strut and including a pair of forward foils extending laterally from opposite sides of said forward strut, the surfaces of said foils having centers of lift located rearwardly of said support axis; rearward strut means mounted to the rearward portion of said hull; and rearward hydrofoil means carried by said rearward strut means.
Claim 16
Dependent Claim
171 words
A hydrofoil watercraft comprising: an elongated hull adapted for propulsion through water; forward strut means mounted to the forward portion of said hull and including a generally flat-sided, vertically oriented forward strut rotatable about a support axis extending downwardly and forwardly relative to the longitudinal axis of said hull, a greater portion of the side surface area of said forward strut being located rearwardly of said support axis whereby upon tipping of said watercraft to one side during propulsion thereof water pressure acting upon said side surface area of said forward strut tends to turn said forward strut means in the direction of said one side; forward hydrofoil means of the fully submerged type carried by said forward strut and including a pair of forward foils extending laterally from opposite sides of said forward strut, the surfaces of said foils having centers of lift located rearwardly of said support axis; rearward strut means mounted to the rearward portion of said hull; and rearward hydrofoil means carried by said rearward strut means.
Claim 17
Dependent Claim
32 words
A hydrofoil watercraft according to claim 14 wherein said rearward strut means includes a generally flat sided, vertically oriented rearward strut and said rearward hydrofoil means are mounted to said rearward strut.
Claim 18
Dependent Claim
23 words
A hydrofoil structure according to claim 15 wherein said forward and rearward struts are longitudinally aligned during straight, non-turning travel of the watercraft.
Claim 19
Dependent Claim
26 words
A hydrofoil structure according to claim 15 wherein said rearward hydrofoil means include a pair of anhedral foils extending from opposite sides of said rearward strut.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-15 | 1977-10-15 | 1978-04-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-15 | 1981-10-15 | 1982-04-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-15 | 1985-10-15 | 1986-04-16 | $7700.00 | Window Closed / Lapsed |