US3772882A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fuel control systems for gas turbine engines
Assignee: ZF International UK Ltd
•
Filing: 1971-12-02
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Granted: 1973-11-20
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Expires: 1991-12-02
Abstract
Abstract A fuel control system includes an acceleration control sensitive to a plurality of engine parameters means sensitive to a socalled hot re-slam condition of the engine and producing an electrical output and means actuable by this output to reduce the maximum fuel flow to the engine.
Inventors
- 👤 E Warne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:29
CPC Classifications
F; F02; F02C; F02C9/00; F02C9/26; F02C9/32
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
101 words
A fuel control system for a gas turbine engine including acceleration control means sensitive to a plurality of engine operating parameters for controlling the rate of flow of fuel to the engine in accordance with said parameters during acceleration of the engine, means sensitive to an engine condition in which air passing through the compressor of the engine is heated by heat stored in the compressor during previous deceleration and arranged to produce an electrical output during such a condition and means actuable by said output for reducing the maximum fuel flow to the engine permitted by said acceleration control means.
Claim 2
Dependent Claim
101 words
A fuel control system for a gas turbine engine including acceleration control means sensitive to a plurality of engine operating parameters for controlling the rate of flow of fuel to the engine in accordance with said parameters during acceleration of the engine, means sensitive to an engine condition in which air passing through the compressor of the engine is heated by heat stored in the compressor during previous deceleration and arranged to produce an electrical output during such a condition and means actuable by said output for reducing the maximum fuel flow to the engine permitted by said acceleration control means.
Claim 3
Dependent Claim
43 words
A fuel control system as claimed in claim 1 in which said means sensitive to said engine condition comprises an amplifier producing a signal which corresponds to the difference between the values of two engine parameters which differ only when said condition exists.
Claim 4
Dependent Claim
67 words
A fuel control system as claimed in claim 2 in which said amplifier produces a signal corresponding to the difference between the actual measureD value of a parameter which fluctuates as a result of heat stored in the engine compressor and the computed value of the same parameter determined by measurement of other parameters which do not fluctuate as a result of heat stored in the compressor.
Claim 5
Dependent Claim
53 words
A fuel control system as claimed in claim 3 wherein the parameter which fluctuates as a result of heat stored in the compressor is the temperature of the air leaving the compressor, and said other parameters being the air temperature at the engine air intake and the speed of rotation of the engine.
Claim 6
Dependent Claim
85 words
A fuel control system as claimed in claim 4 which said amplifier has inputs from means for generating a first electrical signal of magnitude proportional to the square of the engine speed, means for producing a second electrical signal of magnitude proportional to the air intake temperature and means for producing a third electrical signal proportional to the temperature of air leaving the compressor and said amplifier produces an output signal proportional to the sum of the first and second signals less the third signal.
Claim 7
Dependent Claim
50 words
A fuel control system as claimed in claim 3 wherein the para-meter which fluctuates as a result of heat stored in the compressor is the temperature of the compressor and, said other parameters are the air temperature at the engine air intake and the speed of rotation of the engine.
Claim 8
Dependent Claim
27 words
A fuel control system as claimed in claim 2 in which the amplifier produces an output corresponding to the difference between two measured temperatures within the engine.
Claim 9
Dependent Claim
27 words
A fuel control system as claimed in claim 7 in which said temperatures are those of the compressor of the engine and the air leaving the compressor.
Claim 10
Dependent Claim
50 words
A fuel control system as claimed in claim 1 in which the means sensitive to said engine condition includes a difference amplifier supplied with a signal corresponding to the temperature of the air leaving the compressor and a delayed signal corresponding to the temperature of the air leaving the compressor.
Claim 11
Dependent Claim
35 words
A fuel control system as claimed in claim 9 including a pair of temperature probes for providing said signals, one of said probes measuring the actual temperature and the other having an increased thermal inertia.
Claim 12
Dependent Claim
16 words
A fuel control system as claimed in claim 10 in which said other probe is lagged.
Claim 13
Dependent Claim
39 words
A fuel control system as claimed in claim 10 in which said other probe is arranged to serve the temperature in a chamber connected to the compressor delivery end and arranged to receive a slow flow of air therefrom.
Claim 14
Dependent Claim
28 words
A fuel control system as claimed in claim 7 in which said means actuated by the output of the amplifier provides a stabilizing feedback signal to the amplifier.
Claim 15
Dependent Claim
55 words
A fuel control system as claimed in claim 13 in which said means actuated by said output comprises a servo-motor connected to a stop arranged to limit movement of a part which is movable in response to one or more of said engine operating parameters and which controls the flow of fuel to the engine.
Claim 16
Dependent Claim
53 words
A fuel control system as claimed in claim 1 in which said acceleration control means includes pressure sensing means connected to the engine compressor and in which said means actuable by said output includes a valve connected to said pressure sensing means for varying the pressure applied thereto when said engine condition occurs
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-19 | 1977-05-21 | 1977-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-19 | 1981-05-21 | 1981-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-19 | 1985-05-21 | 1985-11-20 | $7700.00 | Window Closed / Lapsed |