Abstract: A cold gas thruster having a two-stage solenoid is provided. Pressurized gas from the inlet flows to the back side of the piston to hold the piston closed. The pressure is maintained by a check ball held by the solenoid armature. When the solenoid is energized, the armature allows the check ball to move to bleed off the pressure holding the piston closed. The piston moves away from its seat and allows the pressurized gas to flow to the outlet creating thrust. When the solenoid coil is de-energized, the check ball is forced against its seat, which blocks the escape of pressure on the back side of the piston, so that it can re-pressurize back up to the inlet pressure. This creates a force imbalance and moves the piston to close the valve and stop the thrust. Different nozzles can be used for different thrust profiles without changing the solenoid.

Abstract: An inline variable sonic valve is provided that includes a housing defining an inlet and an outlet positioned inline along a gas flow axis. A contoured metering plug is fixed within the housing and a diverging sleeve is movably positioned within the housing downstream of the contoured metering plug. An actuator is positioned offline from the gas flow axis and is configured to move the diverging sleeve within the housing relative to the contoured metering plug fixed therein to vary a gas metering area defined between the contoured metering plug and the diverging sleeve. The actuator may be hydraulic, fueldraulic, pneumatic, or electric, and may drive the diverging sleeve discretely to an open or a closed position, or to a variable position between the open and closed position when a position senor is included to meter the flow therethrough.

Abstract: An inline variable sonic valve is provided that includes a housing defining an inlet and an outlet positioned inline along a gas flow axis. A contoured metering plug is fixed within the housing and a diverging sleeve is movably positioned within the housing downstream of the contoured metering plug. An actuator is positioned offline from the gas flow axis and is configured to move the diverging sleeve within the housing relative to the contoured metering plug fixed therein to vary a gas metering area defined between the contoured metering plug and the diverging sleeve. The actuator may be hydraulic, fueldraulic, pneumatic, or electric, and may drive the diverging sleeve discretely to an open or a closed position, or to a variable position between the open and closed position when a position senor is included to meter the flow therethrough.

Abstract: A combined ball valve for compressor bleed air modulation is provided. The combined ball valve includes a housing defining an inlet, and first and second outlets. A metering element is positioned within the housing and within a flow path extending from the inlet to the first and second outlets. The metering element includes first and second flow ports and is rotatable within the housing to modulate compressor bleed air from the inlet to neither, one, or both of the first and second outlets. The combined ball valve utilizes high temperature materials in a relatively lightweight package.

Abstract: The subject matter of this specification can be embodied in, among other things, a positioning device that includes an actuator assembly configured to actuate an output shaft based on an input signal, and a position sensor assembly. The position sensor assembly includes a position sensor configured to detect a position of an input shaft not directly coupled to the output shaft, a first input receiver configured to receive the input signal, a first output transmitter configured to provide an output signal based on the position of the input shaft, and a second output transmitter configured to provide another output signal indicative of a failure of at least one of the input shaft and the output shaft. A moveable member is coupled to both the output shaft and the input shaft and is configured to alter the positional configuration of the input shaft and to be actuated by the output shaft.

Abstract: The subject matter of this specification can be embodied in, among other things, a positioning device that includes an actuator assembly configured to actuate an output shaft based on an input signal, and a position sensor assembly. The position sensor assembly includes a position sensor configured to detect a position of an input shaft not directly coupled to the output shaft, a first input receiver configured to receive the input signal, a first output transmitter configured to provide an output signal based on the position of the input shaft, and a second output transmitter configured to provide another output signal indicative of a failure of at least one of the input shaft and the output shaft. A moveable member is coupled to both the output shaft and the input shaft and is configured to alter the positional configuration of the input shaft and to be actuated by the output shaft.

Abstract: A block valve includes a valve body having an interior chamber between an inlet port and an outlet port, with the valve body including a vent port positioned in the valve body. The block valve further includes a valve closure element located within the chamber, with the valve closure element having a fluid passage therethrough. The valve closure element is movable relative to the valve body between a first position, where the fluid passage is at least partially alignable with the inlet port and the outlet port, and a second position, where a sealing surface of the valve closure element seals the inlet port and the outlet port from the chamber. The valve closure element includes a vent channel positioned in fluid communication with the vent port and the fluid passage of the valve closure element.

Abstract: A combined ball valve for compressor bleed air modulation is provided. The combined ball valve includes a housing defining an inlet, and first and second outlets. A metering element is positioned within the housing and within a flow path extending from the inlet to the first and second outlets. The metering element includes first and second flow ports and is rotatable within the housing to modulate compressor bleed air from the inlet to neither, one, or both of the first and second outlets. The combined ball valve utilizes high temperature materials in a relatively lightweight package.

Abstract: A fail safe mechanism having a return member, valve stem extension, energy storage member, and locking assembly. The valve stem extension is driven by an electrical actuator and configured to drive the return member in a first direction and to be driven by the return member in a second direction. The energy storage member is configured to store energy when the electrical actuator causes the valve stem extension to drive the return member in the first direction and to release the energy stored therein when a disruption of power causes the return member to drive the valve stem extension in the second direction. The locking assembly is configured to hold the return member in a cocked position such that the valve stem extension rotates with the valve independently of the return member and free of influence from the energy storage member while the power is applied to the electrical actuator.

Abstract: A fail safe mechanism having a return member, valve stem extension, energy storage member, and locking assembly. The valve stem extension is driven by an electrical actuator and configured to drive the return member in a first direction and to be driven by the return member in a second direction. The energy storage member is configured to store energy when the electrical actuator causes the valve stem extension to drive the return member in the first direction and to release the energy stored therein when a disruption of power causes the return member to drive the valve stem extension in the second direction. The locking assembly is configured to hold the return member in a cocked position such that the valve stem extension rotates with the valve independently of the return member and free of influence from the energy storage member while the power is applied to the electrical actuator.

Abstract: A redundant sealing system with secondary containment for preventing leakage of fluid along a valve shaft is provided. The system comprises a first set of dynamic seals, a second set of dynamic seals, an auxiliary barrier fluid chamber, and a barrier fluid indicator. The first and second set of dynamic seals are in spaced relation to each other a distance equal to or further than a maximum stroke length of an actuatable valve stem. The auxiliary barrier fluid chamber is interposed between the first and second sets of dynamic seals. The barrier fluid indicator has a piston in a primary barrier fluid chamber. A first face of the piston is exposed to the auxiliary barrier fluid chamber. A second face of the piston is exposed to a barrier fluid and inhibited from fluid communication with the auxiliary barrier fluid chamber by a dynamic seal in the first set of dynamic seals.