Patent US3847104A successfully refreshed from Google Patents.
US3847104A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Marine stern rudder blade
Assignee: Individual
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Filing: 1972-12-12
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Granted: 1974-11-12
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Expires: 1992-12-12
Abstract
Abstract A single blade stern rudder having divergent side wall surfaces near the trailing edge to provide the part of the rudder blade of maximum cross-sectional width near the rudder trailing edge and remote from the rudder pivot axis. Such a rudder may be of the partly-balanced type without a stationary stern post and may have a divergent-convergent cross-section away from the said divergent side wall surface region.
Inventors
- 👤 N Kaufer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 05:43
CPC Classifications
B; B63; B63H; B63H25/00; B63H25/06; B63H25/38
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
258 words
A single-blade rudder secured to the stern of a ship for motion about a vertical pivot axis into opposite extreme or hardabout positions, the ship having a screw that generates a screw wash extending parallel to the forward direction of straight-line travel of the ship, the screw having a radius and a rotational outline, the rudder being situated in its entirety rearwardly of said screw in central alignment therewith, comprising in combination: a. a leading part extending from said pivot axis forwardly thereof and having a horizontally measured length dimension at least as large as the screw radius; and b. a trailing part extending from said pivot axis rearwardly thereof, said trailing part having 1. a front portion extending from said pivot axis rearwardly thereof and having a horizontally measured length dimension at least as large as the screw radius, whereby a projection of said rotational outline of said screw onto said rudder parallel to said direction is substantially fully within the combined area of said leading part and said front portion of said trailing part in either extreme position of the rudder for receiving the entire screw wash, said leading part and said front portion of said trailing part effecting a first deflection of the screw wash; 2. a rear portion adjoining a rear terminus of said front portion and extending rearwardly thereof, said rear portion including rearwardly divergent lateral wall surfaces for effecting a second deflection of the screw wash subsequent to its said first deflection when said rudder is in either of its extreme positions.
Claim 2
Dependent Claim
258 words
A single-blade rudder secured to the stern of a ship for motion about a vertical pivot axis into opposite extreme or hardabout positions, the ship having a screw that generates a screw wash extending parallel to the forward direction of straight-line travel of the ship, the screw having a radius and a rotational outline, the rudder being situated in its entirety rearwardly of said screw in central alignment therewith, comprising in combination: a. a leading part extending from said pivot axis forwardly thereof and having a horizontally measured length dimension at least as large as the screw radius; and b. a trailing part extending from said pivot axis rearwardly thereof, said trailing part having 1. a front portion extending from said pivot axis rearwardly thereof and having a horizontally measured length dimension at least as large as the screw radius, whereby a projection of said rotational outline of said screw onto said rudder parallel to said direction is substantially fully within the combined area of said leading part and said front portion of said trailing part in either extreme position of the rudder for receiving the entire screw wash, said leading part and said front portion of said trailing part effecting a first deflection of the screw wash; 2. a rear portion adjoining a rear terminus of said front portion and extending rearwardly thereof, said rear portion including rearwardly divergent lateral wall surfaces for effecting a second deflection of the screw wash subsequent to its said first deflection when said rudder is in either of its extreme positions.
Claim 3
Dependent Claim
61 words
A rudder as defined in claim 1, wherein said divergent wall surfaces of said rear portion are spaced from said pivot axis at a distance that is greater than said screw radius, whereby said divergent wall surfaces of said rear portion are situated externally of said projection Of said screw outline when said rudder is in either of said extreme positions.
Claim 4
Dependent Claim
49 words
a rear portion adjoining a rear terminus of said front portion and extending rearwardly thereof, said rear portion including rearwardly divergent lateral wall surfaces for effecting a second deflection of the screw wash subsequent to its said first deflection when said rudder is in either of its extreme positions.
Claim 5
Dependent Claim
49 words
a rear portion adjoining a rear terminus of said front portion and extending rearwardly thereof, said rear portion including rearwardly divergent lateral wall surfaces for effecting a second deflection of the screw wash subsequent to its said first deflection when said rudder is in either of its extreme positions.
Claim 6
Dependent Claim
30 words
A rudder as defined in claim 1, wherein the horizontally measured maximum distance between said divergent lateral wall surfaces constitutes the horizontally measured maximum cross-sectional width of the entire rudder.
Claim 7
Dependent Claim
34 words
A rudder as defined in claim 1, wherein said leading part is formed of rearwardly divergent vertical wall surfaces, said front portion of said trailing part is formed of rearwardly convergent vertical wall surfaces.
Claim 8
Dependent Claim
36 words
A rudder as defined in claim 1, wherein the ratio of the length dimension of said trailing part to the length dimension of said leading part is smaller than 2:1, said length dimensions are horizontally measured.
Claim 9
Dependent Claim
36 words
A rudder as defined in claim 1, wherein said leading part has an extreme leading edge having a cutter-like configuration of a width substantially less than the mean blade width measured horizontally transversely to said direction.
Claim 10
Dependent Claim
28 words
A rudder as defined in claim 6, said rudder having a central longitudinal vertical plane, said leading edge includes a strip of sheet metal extending in said plane.
Claim 11
Dependent Claim
25 words
A rudder as defined in claim 1, wherein each of said divergent wall surfaces of said rear portion is formed by a free web plate.
Claim 12
Dependent Claim
21 words
A rudder as defined in claim 8, wherein said web plates have an airfoil cross section with a rearwardly tapering outline.
Claim 13
Dependent Claim
20 words
A rudder as defined in claim 8, including means defining throughflow slots between said outwardly projecting plates and said blade.
Claim 14
Dependent Claim
64 words
A rudder as defined in claim 1, including flow-guiding plate means extending laterally outwardly to either side of the rudder in planes transverse to said pivot axis, said flow-guiding plate means intersect said divergent wall surfaces of said rear portion, whereby in use of the rudder the screw wash is confined against movement clear of the influence of the rudder in a vertical direction.
Claim 15
Dependent Claim
54 words
A rudder as defined in claim 11, wherein said flow-guiding plate means extend in two vertically spaced planes each lying externally of said projection of said outline, said divergent wall surfaces of said rear portion are formed by free web plates projecting outwardly of the rudder blade and secured to said flow-guiding plate means.
Claim 16
Dependent Claim
115 words
A marine single blade stern rudder comprising a rudder blade having leading and trailing parts, means for receiving a pivot shaft on a pivot axis for mounting said rudder on a vessel, said rudder blade having at its trailing part divergent side wall surface means, said rudder blade having its maximum cross-sectional width at said divergent side wall surface means, flow-guiding plate means extending laterally outwardly to either side of the rudder in planes transverse to said pivot axis whereby in use of the rudder the screw wash is confined against movement clear of the influence of the rudder in a vertical direction, said flow-guiding plate means intersect said divergent side wall surface defining means.
Claim 17
Dependent Claim
115 words
A marine single blade stern rudder comprising a rudder blade having leading and trailing parts, means for receiving a pivot shaft on a pivot axis for mounting said rudder on a vessel, said rudder blade having at its trailing part divergent side wall surface means, said rudder blade having its maximum cross-sectional width at said divergent side wall surface means, flow-guiding plate means extending laterally outwardly to either side of the rudder in planes transverse to said pivot axis whereby in use of the rudder the screw wash is confined against movement clear of the influence of the rudder in a vertical direction, said flow-guiding plate means intersect said divergent side wall surface defining means.
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) | 1977-11-11 | 1978-05-13 | 1978-11-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-11 | 1982-05-13 | 1982-11-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-11 | 1986-05-13 | 1986-11-12 | $7700.00 | Window Closed / Lapsed |