US4069662A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Clearance control for gas turbine engine
Assignee: RTX Corp
•
Filing: 1975-12-05
•
Granted: 1978-01-24
•
Expires: 1995-12-05
Abstract
Abstract The clearance between the outer air seal of a gas turbine engine and the tip of the turbine rotor is controlled by selectively turning on and off or modulating the cool air supply which is directed in proximity to the air seal supporting structure so as to control its thermal growth. The cooling causes shrinkage thereby holding the clearance low and effectively reducing fuel consumption.
Inventors
- 👤 Ira H. Redinger, Jr.
- 👤 David Sadowsky
- 👤 Philip S. Stripinis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:51
CPC Classifications
F; F01; F01D; F01D11/00; F01D11/08; F01D11/14; F01D11/20; F01D11/24
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
79 words
For a turbine type power plant having an engine case and a rotating machinery section rotatably supported therein and seal means adjacent the tip of the rotating machinery and attached to said engine case, means for controlling the gap between the tip of the rotating machinery and said seal means, said means includes means for squirting cool air on said engine case for impingement cooling thereof, and control means for turning on and off said cool air squirting means.
Claim 2
Dependent Claim
79 words
For a turbine type power plant having an engine case and a rotating machinery section rotatably supported therein and seal means adjacent the tip of the rotating machinery and attached to said engine case, means for controlling the gap between the tip of the rotating machinery and said seal means, said means includes means for squirting cool air on said engine case for impingement cooling thereof, and control means for turning on and off said cool air squirting means.
Claim 3
Dependent Claim
20 words
For a turbine type power plant as claimed in claim 1 wherein said squirting means is external of said casing.
Claim 4
Dependent Claim
20 words
For a turbine type power plant as claimed in claim 1 including means for supporting said seal to said casing.
Claim 5
Dependent Claim
21 words
For a turbine type power plant as claimed in claim 1 wherein said control means responds to an engine operating parameter.
Claim 6
Dependent Claim
27 words
For a turbine type power plant as claimed in claim 1 including means responsive to altitude for rendering said gap control means inoperative below a predetermined altitude.
Claim 7
Dependent Claim
19 words
For a turbine type power plant as claimed in claim 4 wherein said engine operating parameter is compressor speed.
Claim 8
Dependent Claim
30 words
For a turbine type of power plant as claimed in claim 1 including a fan discharge duct and connection between said fan discharge duct and said cool air squirting means.
Claim 9
Dependent Claim
150 words
For an aircraft powered by a turbine type power plant having a turbine and operable over a given power range, a turbine case an air seal circumferentially mounted around the turbine, and attached to the turbine case means for controlling the opening of the clearance between the tip of the turbine and said air seal, said means including a source of cooling air, connection means connected to said source for conducting the cooling air to impinge on the turbine case in proximity of said air seal, valve means operable from an on to off position in said connection means for regulating the flow therein and blocking off flow from said source when in the closed position, and means responsive to an engine operating parameter for controlling said valve means and including turning on said valve means when said power plant is at a power less than that required for take-off.
Claim 10
Dependent Claim
150 words
For an aircraft powered by a turbine type power plant having a turbine and operable over a given power range, a turbine case an air seal circumferentially mounted around the turbine, and attached to the turbine case means for controlling the opening of the clearance between the tip of the turbine and said air seal, said means including a source of cooling air, connection means connected to said source for conducting the cooling air to impinge on the turbine case in proximity of said air seal, valve means operable from an on to off position in said connection means for regulating the flow therein and blocking off flow from said source when in the closed position, and means responsive to an engine operating parameter for controlling said valve means and including turning on said valve means when said power plant is at a power less than that required for take-off.
Claim 11
Dependent Claim
16 words
For an aircraft as claimed in claim 8 wherein said engine operating parameter is compressor speed.
Claim 12
Dependent Claim
37 words
For an aircraft as in claim 8 wherein said control means turns on said valve means substantially at a power level commensurate with propelling the aircraft at its maximum cruise condition and remains on during said condition.
Claim 13
Dependent Claim
17 words
For a turbine type power plant as in claim 1 wherein said rotating machinery is the turbine.
References Cited (Backward Citations)
US2811833A
Cited
US2994472A
Cited
US3141651A
Cited
US3301526A
Cited
US3453825A
Cited
US3736069A
Cited
US3583824A
Cited
US3736751A
Cited
US3751909A
Cited
US3742705A
Cited
US3869222A
Cited
US3975901A
Cited
US3966354A
Cited
US3957391A
Cited
US3986720A
Cited
US4005946A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-01-23 | 1981-07-25 | 1982-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-23 | 1985-07-25 | 1986-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-23 | 1989-07-25 | 1990-01-24 | $7700.00 | Window Closed / Lapsed |