Abstract: A fuel flow dividing ecology valve conveys fuel from a fuel source to at least a secondary gas turbine engine intake manifold during engine operation and withdraws fuel therefrom upon cessation of engine operation. The valve includes a flow dividing valve portion having an inlet coupled to the fuel source and an outlet coupled to the secondary manifold. The valve also includes an ecology valve portion controlled by the fuel pressure differential between the fuel source and the flow restricting inlet. The ecology valve portion includes a housing with a movable piston disposed therein. The piston defines, in conjunction with the housing, a variable volume chamber for withdrawing fuel from the engine intake manifolds. When the engine is de-energized, the piston moves from a first position toward a second position thereby purging the manifolds of fuel.

Abstract: A method and apparatus for an electro-hydraulic actuator (1) having mechanical feedback provide closed loop control with a high degree of accuracy. The electro-hydraulic actuator (1) includes a current versus load generator (10), a single-stage servomechanism (20, 21, 22, 23), and a device (24, 25, 40, 41) for providing a mechanical feedback force for offsetting an input force (Fsol) of the current versus load generator (10).

Abstract: A fuel metering device (101) and method for metering fuel to an engine (129) provides bumpless transfer to a backup mode. A common cavity (125) provides pressure relief, fuel metering and bypass of fuel flow. A metering valve (120) for scheduling fuel flow to the engine (129) and the metering valve (120) is controlled in either a primary mode or a backup mode. A pressure relief valve (123) limits the maximum pump discharge pressure of a fuel pump. A bypass valve (122) maintains a constant pressure across the metering valve (120) by redirecting non-metered fuel flow back to a pump stage inlet. An electrical clutch (131) determines whether the metering valve (120) function is accomplished by said primary mode or said backup mode. Bumpless transfer to a backup is accomplished automatically.

Abstract: A fuel flow dividing ecology valve conveys fuel from a fuel source to at least a secondary gas turbine engine intake manifold during engine operation and withdraws fuel therefrom upon cessation of engine operation. The valve includes a flow dividing valve portion having an inlet coupled to the fuel source and an outlet coupled to the secondary manifold. The valve also includes an ecology valve portion controlled by the fuel pressure differential between the fuel source and the flow restricting inlet. The ecology valve portion includes a housing with a movable piston disposed therein. The piston defines, in conjunction with the housing, a variable volume chamber for withdrawing fuel from the engine intake manifolds. When the engine is de-energized, the piston moves from a first position toward a second position thereby purging the manifolds of fuel.

Abstract: A method and apparatus for an electro-hydraulic actuator (1) having mechanical feedback provide closed loop control with a high degree of accuracy. The electro-hydraulic actuator (1) includes a current versus load generator (10), a single-stage servomechanism (20, 21, 22, 23), and a device (24, 25, 40, 41) for providing a mechanical feedback force for offsetting an input force (Fsol) of the current versus load generator (10).

Abstract: A fuel metering device (101) and method for metering fuel to an engine (129) provides bumpless transfer to a backup mode. A common cavity (125) provides pressure relief, fuel metering and bypass of fuel flow. A metering valve (120) for scheduling fuel flow to the engine (129) and the metering valve (120) is controlled in either a primary mode or a backup mode. A pressure relief valve (123) limits the maximum pump discharge pressure of a fuel pump. A bypass valve (122) maintains a constant pressure across the metering valve (120) by redirecting non-metered fuel flow back to a pump stage inlet. An electrical clutch (131) determines whether the metering valve (120) function is accomplished by said primary mode or said backup mode. Bumpless transfer to a backup is accomplished automatically.

Abstract: A fuel flow dividing ecology valve (35, 59) selectively conveys fuel from a fuel source (31) to at least a secondary gas turbine engine intake manifold (25) during engine operation and withdraws fuel therefrom upon cessation of engine operation. The valve includes a flow dividing valve portion (41) having an inlet (65) coupled to the fuel source and an outlet (67) coupled to the secondary manifold. The flow dividing valve portion transitions from a fuel flow blocking condition to a condition in which fuel may flow from the source to the manifold solely in response to the fuel pressure differential between the inlet and the outlet. The valve also includes an ecology valve portion (43) controlled solely by the fuel pressure differential between the dividing valve portion inlet and outlet for withdrawing fuel from the secondary engine intake manifold when the engine is de-energized thereby purging the manifold of fuel, and returning withdrawn fuel to the manifold during subsequent engine operation.

Abstract: A fuel metering device (101) and method for metering fuel to an engine (129) provides bumpless transfer to a backup mode. A common cavity (125) provides pressure relief, fuel metering and bypass of fuel flow. A metering valve (120) for scheduling fuel flow to the engine (129) and the metering valve (120) is controlled in either a primary mode or a backup mode. A pressure relief valve (123) limits the maximum pump discharge pressure of a fuel pump. A bypass valve (122) maintains a constant pressure across the metering valve (120) by redirecting non-metered fuel flow back to a pump stage inlet. An electrical clutch (131) determines whether the metering valve (120) function is accomplished by said primary mode or said backup mode. Bumpless transfer to a backup is accomplished automatically.

Abstract: A turbine engine (49) fuel delivery system of the type including a pneumatic governor has an electronic governor and an engine excess stress avoidance feature which disable the pneumatic governor (70) so long as the engine speed exceeds a prescribed value and an electronic control unit (45) continues to function properly. The system transfers governing responsibility to the electronic control unit (45) which controls a torque motor and solenoid valve fuel diversion line (22). The system monitors an engine (49) operating parameter such as gas generator speed (37), power turbine speed, engine output torque, or engine temperature and further diminishes fuel flow to the engine (49) when the monitored parameter exceeds a threshold value. The system resumes normal speed governoring flow when that parameter returns to an acceptable level.

Abstract: A turbine engine (49) fuel delivery system of the type including a pneumatic governor has an electronic governor and an engine excess stress avoidance feature which disable the pneumatic governor (70) so long as the engine speed exceeds a prescribed value and an electronic control unit (45) continues to function properly. The system transfers governing responsibility to the electronic control unit (45) which controls a torque motor and solenoid valve fuel diversion line (22). The system monitors an engine (49) operating parameter such as gas generator speed (37), power turbine speed, engine output torque, or engine temperature and further diminishes fuel flow to the engine (49) when the monitored parameter exceeds a threshold value. The system resumes normal speed governoring flow when that parameter returns to an acceptable level.

Abstract: A turbine engine fuel delivery system (10) and method has, in addition to the conventional fuel bypass (20) for diverting fuel exiting a fuel control (17) away from the engine (49) and back to a fuel pump (15) to maintain a relatively constant pressure differential across the fuel control (17), a separate controllable flow fuel bypass (21) for selectively diverting fuel exiting the fuel control (17) away from the engine (49) and back to the fuel pump (15) to decrease the rate of fuel flow to the engine (49) and correct an overtemperature condition, and an arrangement for enabling the controllable fuel flow bypass (21) during engine (49) start-up and disabling the controllable fuel flow bypass (21) when the engine (49) reaches normal idle speed. Once an engine (49) start or light off is detected, the system (10) automatically prevents turbine outlet temperature exceedences by reducing metered fuel flow to the engine nozzle. The controllable fuel bypass (21) includes a solenoid operable valve (29).

Abstract: A turbine engine (49) fuel delivery system of the type including a pneumatic governor has an electronic governor and an engine excess stress avoidance feature which disable the pneumatic governor (70) so long as the engine speed exceeds a prescribed value and an electronic control unit (45) continues to function properly. The system transfers governing responsibility to the electronic control unit (45) which controls a torque motor and solenoid valve fuel diversion line (22). The system monitors an engine (49) operating parameter such as gas generator speed (37), power turbine speed, engine output torque, or engine temperature and further diminishes fuel flow to the engine (49) when the monitored parameter exceeds a threshold value.