US3786992A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable area nozzle for a gas turbine engine
Assignee: Rolls Royce PLC
•
Filing: 1972-05-31
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Granted: 1974-01-22
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Expires: 1992-05-31
Abstract
Abstract A variable area nozzle for a gas turbine engine comprises an annular array of primary flap members pivoted at their upstream ends for movement of their downstream ends towards or away from the axis of the array. The primary flap members are provided with roller tracks which co-operate with roller tracks of adjacent primary flap members to define tapered roller trackways. Rollers are positioned in the roller trackways such that relative axial movement between the rollers and roller trackways urges the downstream ends of the primary flap members towards or away from the axis of the array.
Inventors
- 👤 N Robinson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:52
CPC Classifications
F; F02; F02K; F02K1/00; F02K1/06; F02K1/12
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
173 words
Variable area nozzle for a gas turbine engine comprising an annular array of primary flap members pivoted at one end for pivotal movement oF their opposite ends towards or away from the central axis of said array, said primary flap members being provided with roller tracks which co-operate with roller tracks of adjacent primary flap members to define tapered roller trackways, roller means being positioned in said tapered roller trackways and means being provided for effecting relative axial movement between said roller means and said tapered roller trackways such as to cause the said opposite ends of said primary flap members to be urged towards or away from the axis of said array wherein the improvement comprises said roller means comprising four parallel rollers mounted such that their centres define a trapezium, the non-parallel sides of which substantially correspond with the taper on said roller trackway, and such that the two upstream rollers are in peripheral contact with each other, with said roller trackway and in peripheral contact with the two downstream rollers.
Claim 2
Dependent Claim
173 words
Variable area nozzle for a gas turbine engine comprising an annular array of primary flap members pivoted at one end for pivotal movement oF their opposite ends towards or away from the central axis of said array, said primary flap members being provided with roller tracks which co-operate with roller tracks of adjacent primary flap members to define tapered roller trackways, roller means being positioned in said tapered roller trackways and means being provided for effecting relative axial movement between said roller means and said tapered roller trackways such as to cause the said opposite ends of said primary flap members to be urged towards or away from the axis of said array wherein the improvement comprises said roller means comprising four parallel rollers mounted such that their centres define a trapezium, the non-parallel sides of which substantially correspond with the taper on said roller trackway, and such that the two upstream rollers are in peripheral contact with each other, with said roller trackway and in peripheral contact with the two downstream rollers.
Claim 3
Dependent Claim
61 words
A variable area nozzle as claimed in claim 1 wherein said primary flap members are pivotally connected at their upstream ends to an axially translatable shroud member, and said rollers are mounted at the downstream end of an axially elongate arm member, the upstream end of which arm member is pivotally connected to the jet pipe of said gas turbine engine.
Claim 4
Dependent Claim
57 words
A variable area nozzle as claimed in claim 1 characterised in that said roller tracks are mounted on axially extending and radially disposed surfaces on said primary flap members by way of extension members such that each roller track faces the axially extending and radially disposed surface of the primary flap member to which it is attached.
Claim 5
Dependent Claim
22 words
A variable area nozzle as claimed in 1 wherein secondary flap members are interposed in overlapping relationship between said primary flap members.
Claim 6
Dependent Claim
40 words
A variable area nozzle as claimed in claim 4 wherein the upstream ends of said primary and secondary flap members are in sliding engagement with the downstream end of said jet pipe so as to provide a gas-tight seal therewith.
Claim 7
Dependent Claim
27 words
A variable area nozzle as claimed in claim 4 wherein said primary and secondary flap members are shaped so as to define a convergent-divergent type of nozzle.
Claim 8
Dependent Claim
29 words
A variable area nozzle as claimed in claim 1 wherein each of said primary flap members has a primary outer flap member fixedly located on its radially outer surface.
Claim 9
Dependent Claim
25 words
A variable area nozzle as claimed in claim 7 wherein secondary outer flap members are interposed in overlapping relationship between said primary outer flap members.
Claim 10
Dependent Claim
31 words
A variable area nozzle as claimed in claim 8 wherein said secondary outer flap members are pivotally mounted by their downstream ends to the downstream ends of said secondary flap members.
Claim 11
Dependent Claim
37 words
A variable area nozzle as claimed in claim 9 characterised in that secondary outer flap members extend across the radially outer surface of said secondary flap members and in overlapping relationship with said primary outer flap members.
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) | 1977-01-21 | 1977-07-23 | 1978-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-21 | 1981-07-23 | 1982-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-21 | 1985-07-23 | 1986-01-22 | $7700.00 | Window Closed / Lapsed |