US3871791A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Blade for fluid flow machines
Assignee: Rolls Royce PLC
•
Filing: 1973-02-20
•
Granted: 1975-03-18
•
Expires: 1993-02-20
Abstract
Abstract The disclosure of this invention relates to a rotor blade for a fan for a gas turbine engine. The blade has in succession an aerofoil, a shank and a root, and the shape of the aerofoil is continued into the shank but at progressively reducing camber so that, whereas adjacent the aerofoil the camber of the shank is the same as that of the aero-foil, adjacent the root the camber of the shank is zero. This leads to a reduction in the stresses produced by a torsion couple arising in operation and acting in the sense tending to reduce the twist of the blade.
Inventors
- 👤 Kenneth Ronald Guy
- 👤 Robert Burns Hood
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:24
CPC Classifications
F; F01; F01D; F01D5/00; F01D5/12; F01D5/14; F01D5/141; Y; Y02; Y02T; Y02T50/00; Y02T50/60
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
176 words
A fan rotor for gas turbine engines comprising: a disc having an axis of rotation, fan blades connected to the disc and extending radially from the periphery thereof, means defining a wall extending circumferentially about said axis in spaced apart relationship to the periphery of the disc, each of said blades comprising an aerofoil of given camber and twist extending radially outwardly of said wall and having a radially inner end adjacent said wall, the chord of said aerofoil generally increasing radially outwardly, a shank extending between the inner end of the aerofoil and a location adjacent the periphery of the disc, said shank having a radially outer end of a cross-section similar in stagger, camber and aerofoil shape to that of the inner end of the aerofoil, and the camber of the shank gradually progressively decreasing from the outer end to the inner end thereof so as to be zero at the inner end of the shank, and means provided at the radially inner end of the shank for connecting the blade to the disc.
Claim 2
Dependent Claim
176 words
A fan rotor for gas turbine engines comprising: a disc having an axis of rotation, fan blades connected to the disc and extending radially from the periphery thereof, means defining a wall extending circumferentially about said axis in spaced apart relationship to the periphery of the disc, each of said blades comprising an aerofoil of given camber and twist extending radially outwardly of said wall and having a radially inner end adjacent said wall, the chord of said aerofoil generally increasing radially outwardly, a shank extending between the inner end of the aerofoil and a location adjacent the periphery of the disc, said shank having a radially outer end of a cross-section similar in stagger, camber and aerofoil shape to that of the inner end of the aerofoil, and the camber of the shank gradually progressively decreasing from the outer end to the inner end thereof so as to be zero at the inner end of the shank, and means provided at the radially inner end of the shank for connecting the blade to the disc.
Claim 3
Dependent Claim
55 words
A fan rotor for gas turbine engines according to claim 1, said connecting means comprising a root portion directly adjacent the radially inner end of the shank and radially inwardly thereof, and the disc including, with respect to each root portion, a recess engageable by the root poRtion to connect the blade to the disc.
Claim 4
Dependent Claim
83 words
A fan rotor for gas turbine engines according to claim 2, wherein the root portion has a plane of symmetry, the shank and aerofoil each having a trailing edge, and the trailing edge of the shank, at the radially outer end thereof, has a common tangent with the trailing edge of the aerofoil at the radially inner end thereof, and the trailing edge of the shank intersects the plane of symmetry of the root portion at the radially inner end of the shank.
Claim 5
Dependent Claim
73 words
A fan rotor for gas turbine engines according to claim 3, the shank and aerofoil each having a leading edge, the leading edge of the shank at the radially outer end thereof has a common tangent with the leading edge of the aerofoil at the radially inner end thereof, and the leading edge of the shank intersects the plane of symmetry of the root portion at the radially inner end of the shank.
References Cited (Backward Citations)
US1772876A
Cited
US1981392A
Cited
US2193616A
Cited
US2327453A
Cited
US2391623A
Cited
US2421890A
Cited
US3012709A
Cited
US2974728A
Cited
US2999668A
Cited
US3173490A
Cited
US3477795A
Cited
US3490852A
Cited
US3576377A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-17 | 1978-09-16 | 1979-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-17 | 1982-09-16 | 1983-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-17 | 1986-09-16 | 1987-03-18 | $7700.00 | Window Closed / Lapsed |