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 actuator converts linear motion into rotational motion. The actuator includes a power piston having a longitudinal axis. The power piston is configured to move back and forth along the longitudinal axis. A slider bearing is disposed within a cross-bore opening in the power piston. The cross-bore opening has a slider bearing axis orthogonal to the longitudinal axis. The slider bearing is configured to move back and forth within the cross-bore opening. An output shaft has a central axis orthogonal to both the longitudinal and the slider bearing axes. The output shaft includes an eccentric shaft pin inserted through a slot in the power piston and disposed within a cavity of the slider bearing. The eccentric shaft pin is offset from the central axis of the output shaft. The reciprocating movement of the power piston causes the slider bearing to move back and forth rotating the output shaft.

Abstract: A rotary actuator is provided. The rotary actuator includes a stator assembly centered along a longitudinal axis of the rotary actuator. The rotary actuator also includes a rotor assembly surrounding the stator assembly. The rotor assembly is rotatable about the longitudinal axis relative to the stator assembly. The rotary actuator also includes first and second bearing assemblies mounted at adjacent opposed axial ends of the stator assembly and connected between the stator assembly and rotor assembly to allow for the rotation of the rotor assembly about the longitudinal axis relative to the stator assembly. A hydraulic actuation arrangement is formed between the rotor assembly and the stator assembly. The hydraulic actuation arrangement includes at least one first pressure chamber and at least one second pressure chamber. At least one of the at least one first pressure chamber and the at least one second pressure chamber has a variable volume.

Abstract: A valve and valve assembly having a hybrid valve member are provided. The valve includes a housing, with an inlet, a primary outlet, and a secondary outlet. The hybrid valve member is rotatably positioned within the housing. The hybrid valve member has a fully closed position wherein the hybrid valve member prevents flow between the inlet and the primary outlet and prevents flow between the inlet and the secondary outlet. The hybrid valve member includes a planar portion and a hemispherical portion on a first side thereof. The planar portion faces the inlet in the fully closed position and the hemispherical portion faces the secondary outlet in the fully closed position.

Abstract: A valve and valve assembly having a hybrid valve member are provided. The valve includes a housing, with an inlet, a primary outlet, and a secondary outlet. The hybrid valve member is rotatably positioned within the housing. The hybrid valve member has a fully closed position wherein the hybrid valve member prevents flow between the inlet and the primary outlet and prevents flow between the inlet and the secondary outlet. The hybrid valve member includes a planar portion and a hemispherical portion on a first side thereof. The planar portion faces the inlet in the fully closed position and the hemispherical portion faces the secondary outlet in the fully closed position.

Abstract: A rotary actuator is provided. The rotary actuator includes a stator assembly centered along a longitudinal axis of the rotary actuator. The rotary actuator also includes a rotor assembly surrounding the stator assembly. The rotor assembly is rotatable about the longitudinal axis relative to the stator assembly. The rotary actuator also includes first and second bearing assemblies mounted at adjacent opposed axial ends of the stator assembly and connected between the stator assembly and rotor assembly to allow for the rotation of the rotor assembly about the longitudinal axis relative to the stator assembly. A hydraulic actuation arrangement is formed between the rotor assembly and the stator assembly. The hydraulic actuation arrangement includes at least one first pressure chamber and at least one second pressure chamber. At least one of the at least one first pressure chamber and the at least one second pressure chamber has a variable volume.

Abstract: A low energy stepper motor driven fuel metering valve (FMV) that eliminates the need for a position sensor is provided. The stepper motor rotates a cam that replaces the flapper valve used in conventional systems. The cam rotation increases the gap between the cam and nozzle on one side of the cam. The gap difference affects the pressures on the spool piston ends, which forces the piston in the direction that will return the cam-nozzle gap to a distance that results in a pressure balance to return. As a result, the relatively low energy stepper motor controls the relatively high energy hydromechanical system via the cam-nozzle-orifice system. The cam is precision machined and assures stroke/degree gain accuracy. The hydraulic system assures the piston tracks the cam essentially perfectly except for the effects of piston stiction forces.

Abstract: A low energy stepper motor driven fuel metering valve (FMV) that eliminates the need for a position sensor is provided. The stepper motor rotates a cam that replaces the flapper valve used in conventional systems. The cam rotation increases the gap between the cam and nozzle on one side of the cam. The gap difference affects the pressures on the spool piston ends, which forces the piston in the direction that will return the cam-nozzle gap to a distance that results in a pressure balance to return. As a result, the relatively low energy stepper motor controls the relatively high energy hydromechanical system via the cam-nozzle-orifice system. The cam is precision machined and assures stroke/degree gain accuracy. The hydraulic system assures the piston tracks the cam essentially perfectly except for the effects of piston stiction forces.

Abstract: A low energy stepper motor driven fuel metering valve (FMV) that eliminates the need for a position sensor is provided. The stepper motor rotates a cam that replaces the flapper valve used in conventional systems. The cam rotation increases the gap between the cam and nozzle on one side of the cam and decreases the gap between the cam and nozzle on the other side. The gap differences affect the pressures on the spool piston ends, which forces the piston in the direction that will re-equalize the cam-nozzle gaps. As a result, the relatively low energy stepper motor controls the relatively high energy hydromechanical system via the dual cam-nozzle-orifice system. The cam is precision machined and assures stroke/degree gain accuracy. The hydraulic system assures the piston tracks the cam essentially perfectly except for the effects of piston stiction forces.

Abstract: A method and apparatus to attenuate a flapper valve from oscillating is presented. An inertia tube is added to the flow path of the flapper valve nozzle, which effectively produces a stabilizing pressure force on the flapper at its natural frequency. The inertia tube has a length to area ratio of greater than approximately 1000 in/in2. The addition of an inertia tube to the nozzle makes the fixed size orifice of the nozzle behave like an orifice having a size that is a function of flow frequency. The inertia tube may be a straight tube, a coiled tube, a thread passage and the like.

Abstract: A latching valve, useable in a multiplexed fluid control system, is switchable between two positions to control working output fluid flow to a corresponding actuator. The valve is latched by deriving a holding force from the working output flow. The latching valve may reside in one of the channels of the multiplexed fluid control system and eliminates the required modulations to hold position and reduces system wear of modulating and multiplexing components. The latching valve includes a working output port coupled with an associated actuator and a control chamber connected to a 3-way multiplexing valve to receive fluid signals. To provide a latching force, the valve includes bleed conduit that bleeds a controlled amount of fluid between the working output port and the control chamber to maintain the pressure in the control chamber. The last position of the latching valve is held until the next selective fluid signal from the modulating valve and multiplexer is received.