US3834158A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Voltage generating circuit for a gas turbine fuel control system
Assignee: Motors Liquidation Co
•
Filing: 1973-03-21
•
Granted: 1974-09-10
•
Expires: 1993-03-21
Abstract
Abstract In a fuel control system for a gas turbine engine, a fuel flow limiting signal is obtained from the difference between a voltage proportional to turbine inlet temperature and a voltage produced by an ambient temperature modified speed reference circuit. In the latter circuit, a first differential comparator passes the greater of a voltage proportional to compressor speed and a first reference voltage. A second differential comparator passes to the circuit output the lowest of the output of the first differential comparator, a second reference voltage and a third reference voltage which varies with ambient air temperature.
Inventors
- 👤 R Oppmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:44
CPC Classifications
F; F02; F02C; F02C9/00; F02C9/26; F02C9/32
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
121 words
In a fuel control system for a gas turbine engine including compressor speed signal voltage generating means, a circuit for generating an output voltage comprising, in combination: first reference voltage generating means; first comparator means responsive to the compressor speed signal voltage and first reference voltage for generating at its output a voltage equal to the larger of said voltages to which it is responsive; second reference voltage generating means; ambient air temperature signal voltage generating means; and second comparator means responsive to the output voltage of the first comparator means, the second reference voltage and the ambient air temperature signal voltage for generating at its output a voltage equal to the smallest of the voltages to which it is responsive.
Claim 2
Dependent Claim
121 words
In a fuel control system for a gas turbine engine including compressor speed signal voltage generating means, a circuit for generating an output voltage comprising, in combination: first reference voltage generating means; first comparator means responsive to the compressor speed signal voltage and first reference voltage for generating at its output a voltage equal to the larger of said voltages to which it is responsive; second reference voltage generating means; ambient air temperature signal voltage generating means; and second comparator means responsive to the output voltage of the first comparator means, the second reference voltage and the ambient air temperature signal voltage for generating at its output a voltage equal to the smallest of the voltages to which it is responsive.
Claim 3
Dependent Claim
220 words
In a fuel control system for a gas turbine engine including compressor speed signal voltage generating means, a circuit for generating an output voltage comprising, in combination: first reference voltage generating means; a first differential comparator having a pair of transistors of NPN conductivity with collectors connected in common to a first potential and emitters connected in common through a resistance to a second potential, the base of one NPN transistor being connected to the compressor speed signal voltage generator and the base of the other NPN transistor being connected to the output of the first reference voltage generating means; second reference voltage generating means; ambient air temperature signal voltage generating means; a second differential comparator comprising first, second and third transistors of PNP conductivity with collectors connected in common to the second potential and emitters connected in common through a resistance to the first potential, the base of the first PNP transistor being connected to the common emitter connection of the first differential comparator, the base of the second PNP transistor being connected to the output of the second reference voltage generating means and the base of the third PNP transistor being connected to the output of the ambient air temperature signal generating means; and circuit output means connected to the common emitter connection of the second differential comparator.
Claim 4
Dependent Claim
220 words
In a fuel control system for a gas turbine engine including compressor speed signal voltage generating means, a circuit for generating an output voltage comprising, in combination: first reference voltage generating means; a first differential comparator having a pair of transistors of NPN conductivity with collectors connected in common to a first potential and emitters connected in common through a resistance to a second potential, the base of one NPN transistor being connected to the compressor speed signal voltage generator and the base of the other NPN transistor being connected to the output of the first reference voltage generating means; second reference voltage generating means; ambient air temperature signal voltage generating means; a second differential comparator comprising first, second and third transistors of PNP conductivity with collectors connected in common to the second potential and emitters connected in common through a resistance to the first potential, the base of the first PNP transistor being connected to the common emitter connection of the first differential comparator, the base of the second PNP transistor being connected to the output of the second reference voltage generating means and the base of the third PNP transistor being connected to the output of the ambient air temperature signal generating means; and circuit output means connected to the common emitter connection of the second differential comparator.
Claim 5
Independent Claim
206 words
A system for controlling fuel flow to a gas turbine engine, the system comprising, in combination: means for generating a throttle demand signal; means for generating an engine speed signal voltage; electrical circuit means responsive to said engine speed signal voltage to generate a modified engine speed signal voltage, said circuit means comprising first reference voltage generating means, first comparator means responsive to said engine speed sIgnal voltage and first reference voltage for generating at its output a voltage equal to the larger of said voltages to which it is responsive, second reference voltage generating means, ambient air temperature signal voltage generating means, and second comparator means responsive to the output voltage of the first comparator means, the second reference voltage and the ambient air temperature signal voltage for generating at its output said modified engine speed signal voltage signal corresponding to the smallest of the voltages to which it is responsive; means for generating an engine temperature signal; means responsive to said modified engine speed signal voltage and said engine temperature signal for generating a third reference voltage; fuel control valve means responsive to said throttle demand signal, engine speed signal voltage, and third reference voltage to control the flow of fuel to said engine.
Claim 6
Independent Claim
206 words
A system for controlling fuel flow to a gas turbine engine, the system comprising, in combination: means for generating a throttle demand signal; means for generating an engine speed signal voltage; electrical circuit means responsive to said engine speed signal voltage to generate a modified engine speed signal voltage, said circuit means comprising first reference voltage generating means, first comparator means responsive to said engine speed sIgnal voltage and first reference voltage for generating at its output a voltage equal to the larger of said voltages to which it is responsive, second reference voltage generating means, ambient air temperature signal voltage generating means, and second comparator means responsive to the output voltage of the first comparator means, the second reference voltage and the ambient air temperature signal voltage for generating at its output said modified engine speed signal voltage signal corresponding to the smallest of the voltages to which it is responsive; means for generating an engine temperature signal; means responsive to said modified engine speed signal voltage and said engine temperature signal for generating a third reference voltage; fuel control valve means responsive to said throttle demand signal, engine speed signal voltage, and third reference voltage to control the flow of fuel to said engine.
Claim 7
Independent Claim
310 words
A system for controlling fuel flow to a gas turbine engine, the system comprising, in combination: means for generating a throttle demand signal; means for generating an engine speed signal voltage; electrical circuit means responsive to said engine speed signal voltage to generate a modified engine speed signal voltage, said circuit means comprising first reference voltage generating means, a first differential comparator having a pair of transistors of NPN conductivity with collectors connected in common to a first potential and emitters connected in common through a resistance to a second potential, the base of one NPN transistor being connected to the engine speed signal voltage generating means and the base of the other NPN transistor being connected to the output of the first reference voltage generating means, second reference voltage generating means, ambient air temperature signal voltage generating means, a second differential comparator comprising first, second and third transistors of PNP conductivity with collectors connected in common to the second potential and emitters connected in common through a resistance to the first potential, the base of the first PNP transistor being connected to the common emitter connection of the first differential comparator, the base of the second PNP transistor being connected to the output of the second reference voltage generating means and the base of the third PNP transistor being connected to the output of the ambient air temperature signal generating means, and circuit output means connected to the common emitter connection of the second differential comparator for supplying said modified engine speed signal voltage; means for generating an engine temperature signal; means responsive to said modified engine speed signal voltage and said engine temperature signal for generating a third reference voltage and fuel control valve means responsive to said throttle demand signal, engine speed signal voltage, and third reference voltage to control the flow of fuel to said engine.
Claim 8
Independent Claim
310 words
A system for controlling fuel flow to a gas turbine engine, the system comprising, in combination: means for generating a throttle demand signal; means for generating an engine speed signal voltage; electrical circuit means responsive to said engine speed signal voltage to generate a modified engine speed signal voltage, said circuit means comprising first reference voltage generating means, a first differential comparator having a pair of transistors of NPN conductivity with collectors connected in common to a first potential and emitters connected in common through a resistance to a second potential, the base of one NPN transistor being connected to the engine speed signal voltage generating means and the base of the other NPN transistor being connected to the output of the first reference voltage generating means, second reference voltage generating means, ambient air temperature signal voltage generating means, a second differential comparator comprising first, second and third transistors of PNP conductivity with collectors connected in common to the second potential and emitters connected in common through a resistance to the first potential, the base of the first PNP transistor being connected to the common emitter connection of the first differential comparator, the base of the second PNP transistor being connected to the output of the second reference voltage generating means and the base of the third PNP transistor being connected to the output of the ambient air temperature signal generating means, and circuit output means connected to the common emitter connection of the second differential comparator for supplying said modified engine speed signal voltage; means for generating an engine temperature signal; means responsive to said modified engine speed signal voltage and said engine temperature signal for generating a third reference voltage and fuel control valve means responsive to said throttle demand signal, engine speed signal voltage, and third reference voltage to control the flow of fuel to said engine.
References Cited (Backward Citations)
US3098356A
Cited
US3421317A
Cited
US3381470A
Cited
US3413806A
Cited
US3587230A
Cited
US3686859A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-09-09 | 1978-03-11 | 1978-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-09 | 1982-03-11 | 1982-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-09 | 1986-03-11 | 1986-09-10 | $7700.00 | Window Closed / Lapsed |