Patent US4083235A successfully refreshed from Google Patents.
US4083235A
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Compressor stall warning system
Assignee: United States Department of the Navy
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Filing: 1977-05-25
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Granted: 1978-04-11
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Expires: 1997-05-25
Abstract
Abstract A compressor stall warning system for jet aircraft gas turbine engines. Theurbine inlet temperature and the compressor rotor speed are monitored and signals representative of the ratio of these two functions and the inlet temperature itself are produced. If the turbine inlet temperature increases while the compressor rotor speed decreases their ratio would increase rapidly. When either this ratio or the turbine inlet temperature alone increase beyond predetermined thresholds, a signal is furnished to the aircraft pilot warning him of impending aircraft engine stall.
Inventors
- 👤 Richard Paul Gallant
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 07:03
CPC Classifications
G; G01; G01M; G01M15/00; G01M15/04; G01M15/042; G01M15/048
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
125 words
A stall warning system for a gas turbine engine having a compressor and turbine comprising: speed sensing means in communication with said compressor operably for providing a signal representative of the rotor rotational speed of said compressor; temperature sensing means in communication with air entering said turbine operably for providing a signal representative of the temperature of said air; means coupled to receive the outputs of said speed sensing means and temperature sensing means for computing the ratio of the turbine inlet temperature and the compressor rotor rotational speed, for providing output signals when either said ratio or the turbine inlet temperature exceeds prescribed thresholds; and signalling means coupled to receive said output signals for providing a warning signal indicative of impending aircraft engine stall.
Claim 2
Dependent Claim
125 words
A stall warning system for a gas turbine engine having a compressor and turbine comprising: speed sensing means in communication with said compressor operably for providing a signal representative of the rotor rotational speed of said compressor; temperature sensing means in communication with air entering said turbine operably for providing a signal representative of the temperature of said air; means coupled to receive the outputs of said speed sensing means and temperature sensing means for computing the ratio of the turbine inlet temperature and the compressor rotor rotational speed, for providing output signals when either said ratio or the turbine inlet temperature exceeds prescribed thresholds; and signalling means coupled to receive said output signals for providing a warning signal indicative of impending aircraft engine stall.
Claim 3
Dependent Claim
30 words
A stall warning system for a gas turbine engine as recited in claim 1, wherein: said temperature sensing means comprises a thermocouple; and said speed sensing means comprises a tachometer.
Claim 4
Dependent Claim
121 words
A stall warning system for a gas turbine engine as recited in claim 1, wherein said computing means comprises: a rectifier connected to said speed sensing means for converting an alternating current to a direct current signal representative of the rotor speed, means coupled to receive the output of said rectifier and said temperature sensing means for calculating said ratio and for providing a signal representative of said ratio; a first comparator coupled to receive one of said temperature representative signals and compare it with a first reference voltage; and a second comparator coupled to receive said ratio representative signal and compare it with a second reference voltage; said first and second comparators providing said output signals to said signalling means.
Claim 5
Dependent Claim
25 words
A stall warning system for a gas turbine engine as recited in claim 3, wherein: said prescribed ratio is 16° C per radian per second.
References Cited (Backward Citations)
US3426322A
Cited
US3872292A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-04-10 | 1981-10-10 | 1982-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-04-10 | 1985-10-10 | 1986-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-04-10 | 1989-10-10 | 1990-04-11 | $7700.00 | Window Closed / Lapsed |