US3893291A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas turbine fuel control
Assignee: Motors Liquidation Co
•
Filing: 1973-08-29
•
Granted: 1975-07-08
•
Expires: 1993-08-29
Abstract
Abstract An electrical fuel control system for a gas turbine engine balances a turbine inlet temperature signal against an allowable turbine inlet temperature signal as means for limiting fuel flow to the engine during acceleration. The turbine temperature signal is generated by a thermocouple which has time lag. This signal is compensated for the time lag and for other parameters to improve engine response by a compensating circuit including an operational amplifier. The amplifier has an integrating feedback to compensate for thermocouple lag and it has a differentiating input of a fuel flow signal to provide damping. It has also a feedback of engine acceleration which reduces the temperature compensation to allow for increased fuel flow in anticipation of increased airflow resulting from the acceleration.
Inventors
- 👤 James L Davis
- 👤 Edward L Lopke
- 👤 Leslie Joseph Pechous
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 13:43
CPC Classifications
F; F02; F02C; F02C9/00; F02C9/26; F02C9/32; F05; F05D; F05D2270/00; F05D2270/01; F05D2270/11; F05D2270/112
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
122 words
A system for controlling fuel flow to a gas turbine engine comprising, in combination, means responsive to a temperature in the engine effective to generate a potential signal representative of the instantaneous temperature of the responsive means and compensating means for the said signal, the compensating means comprising means for adding a function of the derivative of the signal, means for adding a function of the derivative of fuel flow to the engine, and means for subtracting a function of acceleration of the engine; the compensating means including an operational amplifier with a non-inverting input receiving the first signal and a fuel flow derivative signal, and with an inverting input receiving an integrated signal from the amplifier output and an acceleration signal.
Claim 2
Independent Claim
122 words
A system for controlling fuel flow to a gas turbine engine comprising, in combination, means responsive to a temperature in the engine effective to generate a potential signal representative of the instantaneous temperature of the responsive means and compensating means for the said signal, the compensating means comprising means for adding a function of the derivative of the signal, means for adding a function of the derivative of fuel flow to the engine, and means for subtracting a function of acceleration of the engine; the compensating means including an operational amplifier with a non-inverting input receiving the first signal and a fuel flow derivative signal, and with an inverting input receiving an integrated signal from the amplifier output and an acceleration signal.
Claim 3
Independent Claim
156 words
A system for controlling fuel flow to a gas turbine engine comprising, in combination, means responsive to a temperature in the engine effective to generate a first potential signal representative of the instantaneous temperature of the responsive means, means effective to generate a second potential signal representative of a control value of the said engine temperature, and fuel control means responsive to the said signals, characterized by the combination therewith of compensating means for the first signal, the compensating means comprising means for adding a function of the derivative of the first signal, means for adding a function of the derivative of fuel flow to the engine, and means for subtracting a function of acceleration of the engine; the compensating means including an operational amplifier with a non-inverting input receiving the first signal and a fuel flow derivative signal, and with an inverting input receiving an integrated signal from the amplifier output and an acceleration signal.
Claim 4
Independent Claim
156 words
A system for controlling fuel flow to a gas turbine engine comprising, in combination, means responsive to a temperature in the engine effective to generate a first potential signal representative of the instantaneous temperature of the responsive means, means effective to generate a second potential signal representative of a control value of the said engine temperature, and fuel control means responsive to the said signals, characterized by the combination therewith of compensating means for the first signal, the compensating means comprising means for adding a function of the derivative of the first signal, means for adding a function of the derivative of fuel flow to the engine, and means for subtracting a function of acceleration of the engine; the compensating means including an operational amplifier with a non-inverting input receiving the first signal and a fuel flow derivative signal, and with an inverting input receiving an integrated signal from the amplifier output and an acceleration signal.
Claim 5
Independent Claim
162 words
A system for controlling fuel flow to a gas turbine engine comprising, in combination, means responsive to a temperature in the engine effective to generate a potential signal representative of the instantaneous temperature of the responsive means and compensating means for the said signal, the compensating means comprising an operational amplifier having a non-inverting input, an inverting input, and an output; means including a first resistor for transmitting the first signal to the non-inverting input; means generating a potential representative of engine fuel flow; a differentiating RC circuit connecting the last-named means to the non-inverting input; a second resistor equal in resistance to the first resistor connecting the output to the inverting input; an integrating capacitor connected to the inverting input and a resistor of relatively small resistance connecting the capacitor to ground; means generating a potential representative of engine speed and a differentiating RC circuit connecting the last-named means to the inverting input; the amplifier output delivering the compensated temperature signal.
Claim 6
Independent Claim
162 words
A system for controlling fuel flow to a gas turbine engine comprising, in combination, means responsive to a temperature in the engine effective to generate a potential signal representative of the instantaneous temperature of the responsive means and compensating means for the said signal, the compensating means comprising an operational amplifier having a non-inverting input, an inverting input, and an output; means including a first resistor for transmitting the first signal to the non-inverting input; means generating a potential representative of engine fuel flow; a differentiating RC circuit connecting the last-named means to the non-inverting input; a second resistor equal in resistance to the first resistor connecting the output to the inverting input; an integrating capacitor connected to the inverting input and a resistor of relatively small resistance connecting the capacitor to ground; means generating a potential representative of engine speed and a differentiating RC circuit connecting the last-named means to the inverting input; the amplifier output delivering the compensated temperature signal.
Claim 7
Independent Claim
195 words
A system for controlling fuel flow to a gas turbine engine comprising, in combination, means responsive to a temperature in the engine effective to generate a first potential signal representative of the instantaneous temperature of the responsive means, means effective to generate a second potential signal representative of a control value of the said engine temperature, and fuel control means responsive to the said signals, characteriZed by the combination therewith of compensating means for the first signal, the compensating means comprising an operational amplifier having a non-inverting input, an inverting input, and an output; means including a first resistor for transmitting the first signal to the non-inverting input; means generating a potential representative of engine fuel flow; a differentiating RC circuit connecting the last-named means to the non-inverting input; a second resistor equal in resistance to the first resistor connecting the output to the inverting input; an integrating capacitor connected to the inverting input and a resistor of relatively small resistance connecting the capacitor to ground; means generating a potential representative of engine speed and a differentiating RC circuit connecting the last-named means to the inverting input; the amplifier output delivering the compensated temperature signal.
Claim 8
Independent Claim
195 words
A system for controlling fuel flow to a gas turbine engine comprising, in combination, means responsive to a temperature in the engine effective to generate a first potential signal representative of the instantaneous temperature of the responsive means, means effective to generate a second potential signal representative of a control value of the said engine temperature, and fuel control means responsive to the said signals, characteriZed by the combination therewith of compensating means for the first signal, the compensating means comprising an operational amplifier having a non-inverting input, an inverting input, and an output; means including a first resistor for transmitting the first signal to the non-inverting input; means generating a potential representative of engine fuel flow; a differentiating RC circuit connecting the last-named means to the non-inverting input; a second resistor equal in resistance to the first resistor connecting the output to the inverting input; an integrating capacitor connected to the inverting input and a resistor of relatively small resistance connecting the capacitor to ground; means generating a potential representative of engine speed and a differentiating RC circuit connecting the last-named means to the inverting input; the amplifier output delivering the compensated temperature signal.
Claim 9
Independent Claim
125 words
A system for controlling fuel flow to a gas turbine engine comprising, in combination, means responsive to a temperature in the engine effective to generate a first potential signal representative of the instantaneous temperature of the responsive means and compensating means for the said signal effective to provide a compensated temperature signal, the compensating means comprising means for adding a function of the derivative of the first signal of the same sign as the derivative of the first signal, means for adding a function of the derivative of the rate of fuel flow to the engine of the same sign as the derivative of fuel flow rate, and means for subtracting a function of acceleration of the engine of the same sign as the acceleration.
Claim 10
Independent Claim
125 words
A system for controlling fuel flow to a gas turbine engine comprising, in combination, means responsive to a temperature in the engine effective to generate a first potential signal representative of the instantaneous temperature of the responsive means and compensating means for the said signal effective to provide a compensated temperature signal, the compensating means comprising means for adding a function of the derivative of the first signal of the same sign as the derivative of the first signal, means for adding a function of the derivative of the rate of fuel flow to the engine of the same sign as the derivative of fuel flow rate, and means for subtracting a function of acceleration of the engine of the same sign as the acceleration.
Claim 11
Independent Claim
157 words
A system for controlling fuel flow to a gas turbine engine comprising, in combination, means responsive to a temperature in the engine effective to generate a first potential signal representative of the instantaneous temperature of the responsive means, means effective to generate a second potential signal representative of a control value of the said engine temperature, and fuel control means responsive to the said signals, characterized by the combination therewith of compensating means for the first signal effective to provide a compensated temperature signal, the compensating means comprising means for adding a function of the derivative of the first signal of the same sign as the derivative of the first signal, means for adding a function of the derivative of the rate of fuel flow to the engine of the same sign as the derivative of fuel flow rate, and means for subtracting a function of acceleration of the engine of the same sign as the acceleration.
Claim 12
Independent Claim
157 words
A system for controlling fuel flow to a gas turbine engine comprising, in combination, means responsive to a temperature in the engine effective to generate a first potential signal representative of the instantaneous temperature of the responsive means, means effective to generate a second potential signal representative of a control value of the said engine temperature, and fuel control means responsive to the said signals, characterized by the combination therewith of compensating means for the first signal effective to provide a compensated temperature signal, the compensating means comprising means for adding a function of the derivative of the first signal of the same sign as the derivative of the first signal, means for adding a function of the derivative of the rate of fuel flow to the engine of the same sign as the derivative of fuel flow rate, and means for subtracting a function of acceleration of the engine of the same sign as the acceleration.
References Cited (Backward Citations)
US2830437A
Cited
US2835450A
Cited
US3098356A
Cited
US3774395A
Cited
US3691405A
Cited
US3747340A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-07 | 1979-01-06 | 1979-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-07 | 1983-01-06 | 1983-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-07 | 1987-01-06 | 1987-07-08 | $7700.00 | Window Closed / Lapsed |