Patent US3807347A successfully refreshed from Google Patents.
US3807347A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Retractable thru-hull drive system for boats
Assignee: Individual
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Filing: 1972-10-20
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Granted: 1974-04-30
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Expires: 1992-10-20
Abstract
Abstract A propeller and drive assembly for boats in particular as an auxiliary power source for sail boats including a drive assembly which is extendible through the hull below the water line of the sail boat into operating position then retractable to a position within the hull. The assembly includes a trunk preferably cylindrical in shape extending from the hull upward and closed by a plate member secured to the bottom of the drive assembly. A plurality of upstanding shafts align the drive assembly for substantially vertical movement. One of said shafts is operably connected to a power source for driving the propeller when the assembly is extended.
Inventors
- 👤 W Baldwin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 09:34
CPC Classifications
B; B63; B63H; B63H5/00; B63H5/07; B63H5/18; B63H5/20; B63H25/00; B63H25/42; B63H2025/425
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
195 words
A retractable drive unit for boats comprising: a drive unit including a propeller, a housing, gear means for driving said propeller and a shaft extending generally upward from said housing when said drive unit is mounted for operation on a boat, a hollow trunk, means securing said trunk to the hull of a boat surrounding an opening therein, guide means secured to said trunk paralleling the shaft of said drive unit, said guide means engaging said drive unit, means coupled to said drive unit to extend and retract said drive unit out of and into said trunk, means coupling said drive unit to a power unit which is fixed relative to the boat, said drive unit at its lower end carrying a closure for the opening in said hull, said guide means comprising a plurality of longitudinally extending rods including an enlarged end engaging said drive unit at its lowermost extent of travel to securely position said drive unit in its operating position; said coupling means including a drive shaft operatively connected to move with said drive unit and to drivingly engage said power unit as said drive unit reaches its lowermost extent of travel.
Claim 2
Dependent Claim
195 words
A retractable drive unit for boats comprising: a drive unit including a propeller, a housing, gear means for driving said propeller and a shaft extending generally upward from said housing when said drive unit is mounted for operation on a boat, a hollow trunk, means securing said trunk to the hull of a boat surrounding an opening therein, guide means secured to said trunk paralleling the shaft of said drive unit, said guide means engaging said drive unit, means coupled to said drive unit to extend and retract said drive unit out of and into said trunk, means coupling said drive unit to a power unit which is fixed relative to the boat, said drive unit at its lower end carrying a closure for the opening in said hull, said guide means comprising a plurality of longitudinally extending rods including an enlarged end engaging said drive unit at its lowermost extent of travel to securely position said drive unit in its operating position; said coupling means including a drive shaft operatively connected to move with said drive unit and to drivingly engage said power unit as said drive unit reaches its lowermost extent of travel.
Claim 3
Dependent Claim
21 words
The combination in accordance with claim 1 wherein said trunk extends within the hull to above the waterline of the boat.
Claim 4
Dependent Claim
55 words
The combination in accordance with claim 1 wherein said trunk includes a mounting plate secured to the hull of said boat and including a generally isosceles triangular opening therethrough with one vertex extending in the direction of the bow of the boat and the triangular opening generally aligned with the center line of the boat.
Claim 5
Dependent Claim
25 words
The combination in accordance with claim 1 wherein said power unit iS mounted outside of said trunk and engages said coupling means above said trunk.
Claim 6
Dependent Claim
47 words
The combination in accordance with claim 1 wherein the end regions of said longitudinally extending rods are tapered outward to larger diameters and said drive unit includes tapered holes positioned to engage the tapered end regions of said rods to secure said drive unit in driving position.
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) | 1977-04-29 | 1977-10-29 | 1978-04-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-29 | 1981-10-29 | 1982-04-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-29 | 1985-10-29 | 1986-04-30 | $7700.00 | Window Closed / Lapsed |