US3697193A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluidfoil section
Assignee: Individual
•
Filing: 1970-12-10
•
Granted: 1972-10-10
•
Expires: 1990-12-10
Abstract
Abstract Airfoil sections having improved lift characteristics are described for use as propeller blades for air or marine craft for wings of aircraft for hydrofoil sections of hydrofoil vessels and for rotor blades in compressor stages of gas turbine engines. The improved section is characterized by a planar upper portion and convex face extending rearwardly of the leading edge for approximately one-third of the chord length of the section whereupon the face assumes a planar shape terminating at the trailing edge in either convergent or parallel relation with the upper surface of the section. The camber line of the trailing edge may be deflected in a direction away from the upper surface at an angle to the mean camber line of the section. Such improved airfoils provide lift by generation of a large positive pressure on the face of the section and only a small negative pressure on the upper surface of the section.
Inventors
- 👤 Adrian Phillips
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:45
CPC Classifications
F; F04; F04D; F04D29/00; F04D29/26; F04D29/32; F04D29/321; F04D29/324; B; B63; B63B; B63B1/00; B63B1/16; B63B1/24; B63B1/248; B63H; B63H1/00; B63H1/02; B63H1/12; B63H1/14; B63H1/26; B64; B64C; B64C11/00; B64C11/16; B64C11/18; B64C3/00; B64C3/10; B64C3/14; B64C2003/144; B64C2003/147; Y; Y02; Y02T; Y02T50/00; Y02T50/10
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
119 words
A fluidfoil section having a leading edge and a trailing edge and an upper surface and a face, said face being the high pressure working surface, said face of said section having a convex shape commencing at the leading edge and terminating intermediate the leading edge and trailing edge whereupon the face assumes a planar shape extending over at least part of said face rearward of said termination, said upper surface of the section having a substantially planar shape extending from the leading edge to adjacent the trailing edge whereby the major portion of lift provided by the section moving through a fluid medium is produced by positive pressure exerted on said face of the section by said medium.
Claim 2
Dependent Claim
119 words
A fluidfoil section having a leading edge and a trailing edge and an upper surface and a face, said face being the high pressure working surface, said face of said section having a convex shape commencing at the leading edge and terminating intermediate the leading edge and trailing edge whereupon the face assumes a planar shape extending over at least part of said face rearward of said termination, said upper surface of the section having a substantially planar shape extending from the leading edge to adjacent the trailing edge whereby the major portion of lift provided by the section moving through a fluid medium is produced by positive pressure exerted on said face of the section by said medium.
Claim 3
Dependent Claim
47 words
A fluidfoil section as claimed in claim 1 wherein: said planar shape of both said upper surface and face extends to the trailing edge of the section, said upper surface and face being convergent towards one another at the trailing edge providing a wedge-shaped cross-sectional configuration thereto.
Claim 4
Dependent Claim
72 words
A fluidfoil section as claimed in claim 1 wherein: said planar shape of the upper surface extends to the trailing edge of the section, said planar edge of the face extends rearwardly from said termination of said convex shape to a position forward of the trailing edge in a plane convergent towards the upper surface whereupon said face assumes a further planar shape parallel to said upper surface at the trailing edge.
Claim 5
Dependent Claim
34 words
A fluidfoil section as claimed in claim 3 wherein: said face assumes a concave shape intermediate those said planar shapes of the face which are respectively convergent towards and parallel to said upper surface.
Claim 6
Dependent Claim
48 words
A fluidfoil section as claimed in claim 1 wherein: the camber line of the trailing edge of said section on both said upper surface and face thereof is deflected in a direction away from the upper surface at an angle to the mean camber line of the section.
Claim 7
Dependent Claim
50 words
A fluidfoil section as claimed in claim 5 wherein: said face has a said convex shape for approximately one-third of the chord length between the leading edge and trailing edge thereof and, said camber line deflection extends forward of said trailing edge for approximately one-sixth of the said chord length.
Claim 8
Dependent Claim
54 words
A fluidfoil section as claimed in claim 2 wherein: said face has a said convex shape for approximately one-third of the chord length between the leading edge and trailing edge thereof and, said upper surface of the section has a convex shape extending from the leading edge for approximately one-sixth of said chord length.
Claim 9
Dependent Claim
69 words
A fluidfoil section as claimed in claim 3 wherein: said face has a said convex shape for approximately one-third of the chord length between the leading edge and trailing edge thereof, said planar shape extends for approximately one-half of said chord length after the termination of said convex shape and, said further planar shape extends approximately one-sixth of said chord length in said parallel relation with said upper surface.
Claim 10
Dependent Claim
31 words
A fluidfoil section as claimed in claim 8 wherein: said upper surface of the section has a convex shape extending from the leading edge for approximately one-sixth of said chord length.
Claim 11
Dependent Claim
96 words
A fluidfoil section as claimed in claim 1 wherein: said planar shape of both the upper surface and face terminate at a position forward of the trailing edge and, said upper surface and face are curved aft of said position towards the trailing edge providing a convex shape to the upper surface and a concentric concave shape to the face whereby the camber line of the trailing edge on both said upper surface and face is deflected in a direction away from the uppeR surface at an angle to the mean camber line of the section.
Claim 12
Dependent Claim
34 words
A fluidfoil section as claimed in claim 10 wherein: said camber line deflection extends forward of said trailing edge for approximately one-sixth of the chord length between the leading edge and trailing edge thereof.
Claim 13
Dependent Claim
52 words
A fluidfoil section as claimed in claim 11 wherein: said face has a said convex shape for approximately one-third of the chord length between the leading edge and the trailing edge thereof and, said planar shape extends for approximately one-half of said chord length aft of the termination of said convex shape.
Claim 14
Dependent Claim
31 words
A fluidfoil section as claimed in claim 12 wherein: said upper surface of the section has a convex shape extending from the leading edge for approximately one-sixth of said chord length.
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) | 1975-10-10 | 1976-04-10 | 1976-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-10 | 1980-04-10 | 1980-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-10 | 1984-04-10 | 1984-10-10 | $7700.00 | Window Closed / Lapsed |