Patent US4487148A successfully refreshed from Google Patents.
US4487148A
Expired / Lapsed
US
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Sailboat
Assignee: UM Corp 4-5-15 ROPPONGI MINATO-KU TOKYO 106 JAPAN A CORP OF JAPAN
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Filing: 1982-09-28
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Granted: 1984-12-11
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Expires: 2002-09-28
Abstract
Abstract A sailboat has a rotatable mast having a pivot mast for holding a sail and a slat member broadening backward from a leading edge to have a streamline section of a wing section together with the pivot mast and arranged along the pivot mast. The mast is rotated to be fixed at a desired position. Not only the sail but also the slat member produces a lift. The production of vortex and exfoliation of laminar layer are suppressed. Reefing and folding of the sail is facilitated.
Inventors
- 👤 Kazuhiro Umeda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:42
CPC Classifications
B; B63; B63B; B63B15/00; B63B15/0083; B63H; B63H9/00; B63H9/04; B63H9/08; B63H9/10; B63H9/1021; B63H2009/105; B63H2009/1057
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
119 words
A sailboat comprising: (a) rotatable mast having a pivot mast for holding the front part of a sail, and for winding said sail therearound and a slat member broadening backward from a leading edge to have a section corresponding to a fore portion of a wing section working together with said pivot mast and arranged along said pivot mast; (b) base for rotatably supporting said pivot mast and said slat member, said slat member being detachably mounted on said base; and (c) means for rotating said base around the axis of said pivot mast, so that said mast can be directed to a direction of maximum lift and for fixing said base after the rotation at a desired position.
Claim 2
Dependent Claim
119 words
A sailboat comprising: (a) rotatable mast having a pivot mast for holding the front part of a sail, and for winding said sail therearound and a slat member broadening backward from a leading edge to have a section corresponding to a fore portion of a wing section working together with said pivot mast and arranged along said pivot mast; (b) base for rotatably supporting said pivot mast and said slat member, said slat member being detachably mounted on said base; and (c) means for rotating said base around the axis of said pivot mast, so that said mast can be directed to a direction of maximum lift and for fixing said base after the rotation at a desired position.
Claim 3
Dependent Claim
33 words
A sailboat as claimed in claim 1, wherein said slat member is provided on the side of said pivot mast opposite to the side that the expanded surface of said sail is held.
Claim 4
Dependent Claim
19 words
A sailboat as claimed in claim 1, wherein said slat member and said pivot mast form a streamline section.
Claim 5
Dependent Claim
21 words
A sailboat as claimed in claim 1, wherein said sail has a wrapping sail as said front part of said sail.
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) | 1987-12-11 | 1988-06-11 | 1988-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-11 | 1992-06-11 | 1992-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-11 | 1996-06-11 | 1996-12-11 | $7700.00 | Window Closed / Lapsed |