Abstract: A fuel nozzle metering valve that includes a spool having an inlet port and an outlet flow port, and a retainer assembled to one end of the spool. A valve liner houses a portion of the spool. The spool is configured to move back and forth within the valve liner. The metering valve is biased in a closed position in which the outlet flow port is disposed entirely within the valve liner. The valve is opened when the spool slides within the valve liner such that some portion of the outlet flow port extends beyond an end of the valve liner. The retainer has a stepped portion configured to abut an end of the retainer at a fuel flow pressure below the expected maximum fuel flow pressure to be used in the fuel nozzle metering valve.

Abstract: A passive flow splitting system for use in a turbine engine control system to provide split fuel flow to two fuel manifolds to supply primary and secondary fuel injectors for the particular combustion zones thereof utilizing intentionally different split ratios dependent on ascending or descending combustion fuel flow is provided. The system includes a passive fuel divider valve (FDV) that includes a primary piston and a secondary piston. The primary piston is moveable independently from the secondary piston during a portion of its stroke, and is hydro-locked to the secondary piston during another portion of its stroke. An ecology valve is also provided to purge the fuel from the primary and/or secondary manifolds during different modes of operation. A transfer valve is included to control the position of ecology piston of the ecology valve.

Abstract: A flame arrestor screw for a solenoid operated gas admission valve. The flame arrestor screw may include a screw body having a first end and an open end. The flame arrestor screw may include a gas passage extending from the open end along a longitudinal axis of the screw body and terminating at a terminal end within the screw body. A through hole may extend through the screw body transverse to the gas passage and in fluid communication with the gas passage.

Abstract: Embodiments of the disclosure relate to a system designed to compensate for flow disturbances when changing a flow rate in the system. The system includes a flow source device having an inlet and an outlet. The inlet is configured to receive fluid at a first pressure, and the outlet is configured to output the fluid at a second pressure that is higher than the first pressure. The system also includes a fluid control device having an inlet port and a drain port. The inlet port of the fluid control device is configured to receive flow from the outlet of the flow source device. Further, the system includes a constant flow regulator configured to provide a leakage flow to a drain output. The constant flow regulator is configured to decrease the leakage flow in response to the drain port of the fluid control device.

Abstract: A housing defines a gaseous fuel inlet and a gaseous fuel outlet. A rotor defines an internal flow passage therethrough that rotates with the rotor to, alternately, allow gaseous fuel flow, or to block gaseous fuel flow, between the inlet and the outlet, based on a position of the rotor. A seal is biased to abut an exterior surface of the rotor. The seal is between the rotor and the outlet. An actuator is rotably coupled to the rotor. The driver is configured to rotate the rotor. A controller is in communication with the driver and is configured to control the driver to rotate at a rate based on an engine speed of the engine.

Abstract: The subject matter of this specification can be embodied in, among other things, a rotary lock assembly that includes a first epicyclic gear assembly having a first sun gear assembly, a first ring gear assembly, and a first planet gear assembly mechanically engaged to the first sun gear assembly and the first ring gear assembly, and a second epicyclic gear assembly having a second sun gear assembly configured to be rotated by the first ring gear assembly, a second ring gear assembly, and a second planet gear assembly mechanically engaged to the second sun gear assembly and the second ring gear assembly.

Abstract: A damped check valve having multi-pressure operation is provided. The check valve includes a liner with a poppet movable within the liner. The liner defines a flow passage aligned along a longitudinal axis defined by the liner. A biasing element is operably coupled between the poppet and the liner to bias a first flow face of the poppet against an annular seat. The first flow face is configured such that a first fluid pressure is required to move the poppet from the closed position to an open position wherein the poppet is unseated from the annular seat and a second fluid pressure is required to hold the poppet in the open position, the second pressure being less than the first pressure. There is a sufficient diametrical clearance between the poppet and the liner which allows for flow control at pressures which are less than the initial opening pressure.

Abstract: Methods and systems for nacelle door electromechanical actuation may include a power distribution unit comprising a motor and differential gears; and a plurality of electromechanical actuators, each coupled to an output of a corresponding one of the differential gears. Each of the electromechanical actuators may include a configurable brake and a mechanical output, where the power distribution unit may provide mechanical torque to one of the electromechanical actuators via the motor and the differential gears based on configuration of the configurable brakes in each of the electromechanical actuators. At least one of the configurable brakes may be an electrically configurable brake. At least one of the configurable brakes may be a mechanically configurable brake. The differential gears may include two or more differential gears for receiving an input torque and supplying an output torque to one of a plurality of outputs of the differential gears.

Abstract: The subject matter of this specification can be embodied in, among other things, a method for controlling a turbine engine that includes receiving a predetermined arming threshold signal, receiving a predetermined triggering threshold signal, receiving a periodic signal from a speed sensor, determining a frequency signal based on the periodic signal, the predetermined arming threshold signal, and the predetermined triggering threshold signal, determining a speed value based on the determined frequency signal, and controlling a speed of a turbine based on the determined speed value.

Abstract: A fuel nozzle metering valve that includes a spool having an inlet port and an outlet flow port, and a retainer assembled to one end of the spool. A valve liner houses a portion of the spool. The spool is configured to move back and forth within the valve liner. The metering valve is biased in a closed position in which the outlet flow port is disposed entirely within the valve liner. The valve is opened when the spool slides within the valve liner such that some portion of the outlet flow port extends beyond an end of the valve liner. The retainer has a stepped portion configured to abut an end of the retainer at a fuel flow pressure below the expected maximum fuel flow pressure to be used in the fuel nozzle metering valve.

Abstract: The subject matter of this specification can be embodied in, among other things, an electrohydraulic positioning control system that includes a shuttle valve configured to direct fluid flow between a selectable one of a first fluid port and a second fluid port, and a fluid outlet configured to be fluidically connected to a fluid actuator, a first servo valve controllable to selectably permit and block flow between the first fluid port, a fluid source, and a fluid drain, a second servo valve controllable to selectably permit and block flow between the second fluid port, the fluid source, and the fluid drain, a first servo controller configured to provide a first health signal and control the first servo valve based on a second health signal, and a second servo controller configured to provide the second health signal and control the second servo valve based on the first health signal.

Abstract: An enhanced safety coil that prevents crack formation and propagation to the coil windings from external sources and prevents exposure to fuel is provided. The enhanced safety coil may be used in a solenoid operated gas admission valve (SOGAV), and includes a plastic encapsulation body having at least one body de-stress feature, a coil wound on the plastic encapsulation body, a sleeve forming an outermost side protective wall configured to accommodate the plastic encapsulation body and coil therewithin, and potting provided between the plastic encapsulation body and the sleeve to seal the coil therein. The body de-stress feature is configured to reduce at least one of a formation or a propagation of a crack through the potting to the coil. The plastic encapsulation body forms retention latches configured to mate with a stator.

Abstract: The subject matter of this specification can be embodied in, among other things, an assembly that includes a piston having a piston inner surface defining a cylindrical cavity and includes a first axial portion, a piston face at a first end of the first axial portion, a second axial portion at a second end of the first axial portion, and a helical piston thread defined upon the piston inner surface, a bushing configured to contact the piston inner surface, and a lock nut configured to engage the piston and the bushing.

Abstract: Methods and systems for an epicyclic gear mechanism that includes a primary differential assembly to selectively drive the fore secondary differential assembly and the aft secondary differential assembly. The fore secondary differential assembly selectively drives one or more fore interfaces (e.g., output gears), whereas the aft secondary differential assembly selectively drives one or more aft interfaces (e.g., output gears). Each of the primary differential assembly, the fore and aft secondary differential assemblies, and the interfaces rotate about a common central axis. The primary differential assembly drives the fore secondary differential assembly via a first sun gear, and drives the aft secondary differential assembly via a second sun gear, both of which rotate about the common central axis. Further, one or more actuators are to activate or deactivate in order to drive or be driven by a selected interface.

Abstract: The subject matter of this specification can be embodied in, among other things, an electric actuator driver that includes a first input port configured to receive an analog electrical servo control signal, a second input port configured to receive a position feedback signal, a first output port, a second output port, and a conversion circuit configured to determine one or more electric motor coil control current levels based on the analog electrical servo control signal and the position feedback signal, provide the one or more electric motor coil control currents based on the determined electric motor coil control current levels at the first output port, determine a feedback signal based on the analog electrical servo control signal, and provide the determined feedback signal at the second output port.

Abstract: A stepper motor driven actuator system is provided. The system includes a stepper motor, a cam, and a gearbox system. The gearbox system operatively connects the stepper motor to the cam. The cam rotates in response to stepping of the stepper motor. The system also includes a valve having a control piston located therein. The control piston is configured to translate in response to rotation of the cam. The system further includes a rotary actuator. The rotary actuator is fluidly connected to the valve, and the rotary actuator is configured to rotate the cam in response to translation of the control piston.

Abstract: A lock and release mechanism includes a primary ring with a first surface and a second surface, each surface including a plurality of channels of varying depths. A secondary ring has first and second surfaces, the first surface including a plurality of channels of varying depths. The channels of the secondary ring are aligned with a portion of an opposing channel of the primary ring. Arranged between the primary and secondary rings are a plurality of low friction elements partially arranged within a channel of the primary ring and partially arranged within an opposing channel of the secondary ring. In order to lock and release the mechanism, the primary ring translates relative to the secondary ring such that the bearing balls move within each channel from a first depth to a second depth greater than the first depth.

Abstract: The subject matter of this specification can be embodied in, among other things, a rotary actuator that includes a housing defining a first arcuate chamber portion and comprising a first cavity, a first open end, a first seal carrier assembly defining a second arcuate chamber portion and comprising a second cavity in fluid communication with the first cavity, a first piston seal, a second open end, and a third open end opposite the second open end, a first face seal in sealing contact with the housing proximal to the first open end and the second open end, a rotary output assembly, and an arcuate-shaped first piston disposed in said housing for reciprocal movement in the first arcuate chamber portion and in the second arcuate chamber portion.

Abstract: Methods and systems for electronic engine control (EEC) systems are disclosed. An EEC monitors and controls operation of an end effector, such as a torque motor. The EEC is configured to command a switchover from an active channel to a standby channel, or vice versa, in response to a trigger (e.g., a command or a fault). The switchover is executed automatically upon identification of the trigger due to the detection of a fault without the need of a command, over a predetermined time or number of cycles within a command signal.

Abstract: The subject matter of this specification can be embodied in, among other things, a fluid valve assembly that includes a first fluid port, a second fluid port, a third fluid port, a valve spool configured to be positioned at a first position, a second position away from the first position, a third position away from the first position opposite the second valve position, the valve spool defining a first fluid duct configured to fluidly connect the first fluid port to the second fluid port in the first valve position, a second fluid duct configured to fluidly connect the first fluid port to the third fluid port in the second valve position, and a third fluid duct configured to fluidly connect the first fluid port to the second fluid port in the third valve position.