Patent US4350008A successfully refreshed from Google Patents.
US4350008A
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US
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Method of starting turbine engines
Assignee: RTX Corp
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Filing: 1979-12-26
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Granted: 1982-09-21
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Expires: 1999-12-26
Abstract
Abstract A method of starting a gas turbine engine, particularly one having a high inertia rotor, in which the engine is cranked until sufficient air flow is available for lightoff, at which time fuel is injected at a fixed rate until ignition occurs, and fuel flow is then increased at a rate that is a function of rotor speed and ambient temperature. During the acceleration to operating speed, the turbine temperature is compared to a temperature reference that is based on rotor speed and ambient temperature and a lower fuel flow rate is selected, if necessary, to prevent overheating within the engine.
Inventors
- 👤 Herbert C. Zickwolf, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:38
CPC Classifications
F; F02; F02C; F02C7/00; F02C7/26
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
65 words
A method of starting a turbine engine including the steps of: cranking the engine until sufficient air flow is available for lightoff; admitting fuel at a fixed flow rate to the engine; igniting the fuel; and then increasing the rotor speed to operating speed by increasing the fuel flow at a rate of change that is a function of both rotor speed and ambient temperature.
Claim 2
Independent Claim
65 words
A method of starting a turbine engine including the steps of: cranking the engine until sufficient air flow is available for lightoff; admitting fuel at a fixed flow rate to the engine; igniting the fuel; and then increasing the rotor speed to operating speed by increasing the fuel flow at a rate of change that is a function of both rotor speed and ambient temperature.
Claim 3
Dependent Claim
27 words
The method of claim 1 including the step of detecting ignition of the fuel by sensing the resulting temperature rise in the combustion chamber of the engine.
Claim 4
Dependent Claim
39 words
The method of claim 1 including the additional step of protecting the engine against turbine overtemperature by causing a fuel flow reduction if the sensed turbine exit temperature exceeds a reference temperature derived from ambient temperature and rotor speed.
Claim 5
Dependent Claim
37 words
The method of claim 3 in which the speed function and ambient temperature generate a signal and the turbine exit temperature generates another signal, the method including selecting the lower value signal for controlling the fuel flow.
References Cited (Backward Citations)
US3520133A
Cited
US3686859A
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US3793825A
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US3793826A
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US3844111A
Cited
US4044554A
Cited
US4274255A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-09-20 | 1986-03-22 | 1986-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-09-20 | 1990-03-22 | 1990-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-09-20 | 1994-03-22 | 1994-09-21 | $7700.00 | Window Closed / Lapsed |