Abstract: A piston assembly includes a housing, a piston positioned within the valve housing, and an inductive proximity probe sensor positioned on the housing configured to detect a position of the piston with the housing. The piston is configured to at least one of rotate or translate axially relative to the housing. The piston includes a variable surface. A fuel control system includes the piston assembly, a servo valve in fluid communication with the piston assembly, and an engine controller. The engine controller is operatively connected to the inductive proximity probe sensor.

Abstract: A piston assembly includes a housing, a piston positioned within the valve housing, and an inductive proximity probe sensor positioned on the housing configured to detect a position of the piston with the housing. The piston is configured to at least one of rotate or translate axially relative to the housing. The piston includes a variable surface. A fuel control system includes the piston assembly, a servo valve in fluid communication with the piston assembly, and an engine controller. The engine controller is operatively connected to the inductive proximity probe sensor.

Abstract: A fuel pumping system of an aircraft, having a first boost pump; a main pump; a main pump feed conduit fluidly coupled to the main pump and configured to receive fuel after it has passed through the first boost pump; a main pump discharge conduit fluidly coupled to the main pump; an ejector fluidly coupled to the main pump feed conduit, between the first boost pump and the main pump; a bypass conduit fluidly coupled to the main pump discharge conduit and the ejector such that the bypass conduit is configured to provide fluid to the ejector drawn from the output of the first boost pump into the main pump; and a backpressure regulating valve fluidly coupled to the bypass conduit, and configured to transition to an open state when pressure in the main pump discharge conduit is above a threshold.

Abstract: A vibration-resistant, flexible metallic seal for use in an electrohydraulic servo valve (EHSV), the EHSV comprising an armature, an armature support comprising a base, and a flapper, the seal surrounding a portion of the flapper, the seal having a first end, a second end, a thickness along a length of the seal between the first end and the second end, the thickness being defined between first and second outer surfaces of the seal, and one or a plurality of convolutions between the first end and the second end, the first end disposed between and hermetically connected to the flapper and the armature, the second end disposed within the first opening and hermetically connected to the base, wherein the seal comprises: a non-porous metal that comprises a first fraction of the thickness; a porous metal comprising a plurality of pores that comprises a second fraction of the thickness; and an elastomeric material encompassed by the pores of the second fraction of the thickness, wherein the second fraction comprises

Abstract: A torque motor valve actuator for use with a valve assembly is provided. The torque motor valve actuator includes an armature spring having a first end portion, a second end portion and a rigid central portion. The first end portion and the second end portion are coupled to the rigid central portion by a respective flexible portion, and the rigid central portion defines a bore that extends along a first axis. The torque motor valve actuator includes an armature having a first end and a second end. The armature extends along a longitudinal axis that is substantially parallel to the first axis of the bore, and the armature is coupled to the bore of the armature spring between the first end and the second end.

Abstract: A torque motor valve actuator for use with a valve assembly is provided. The torque motor valve actuator includes an armature spring having a first end portion, a second end portion and a rigid central portion. The first end portion and the second end portion are coupled to the rigid central portion by a respective flexible portion, and the rigid central portion defines a bore that extends along a first axis. The torque motor valve actuator includes an armature having a first end and a second end. The armature extends along a longitudinal axis that is substantially parallel to the first axis of the bore, and the armature is coupled to the bore of the armature spring between the first end and the second end.

Abstract: A vibration-resistant, flexible metallic seal for use in an electrohydraulic servo valve (EHSV), the EHSV comprising an armature, an armature support comprising a base, and a flapper, the seal surrounding a portion of the flapper, the seal having a first end, a second end, a thickness along a length of the seal between the first end and the second end, the thickness being defined between first and second outer surfaces of the seal, and one or a plurality of convolutions between the first end and the second end, the first end disposed between and hermetically connected to the flapper and the armature, the second end disposed within the first opening and hermetically connected to the base, wherein the seal comprises: a non-porous metal that comprises a first fraction of the thickness; a porous metal comprising a plurality of pores that comprises a second fraction of the thickness; and an elastomeric material encompassed by the pores of the second fraction of the thickness, wherein the second fraction comprises

Abstract: Armature springs configured to be coupled to and bias an armature of a torque motor valve actuator to a null position are provided. The armature spring comprises a rigid central portion, opposed end portions, and a flexible portion intermediate the rigid central portion and each end portion. The rigid central portion, the opposed end portions, and the flexible portions define a variable cross section torsion bar with the flexible portions comprising reduced cross-sectional portions of the torsion bar relative to the rigid central portion and opposed end portions. Armature assemblies and torque motor valve actuators are also provided.

Abstract: Armature springs configured to be coupled to and bias an armature of a torque motor valve actuator to a null position are provided. The armature spring comprises a rigid central portion, opposed end portions, and a flexible portion intermediate the rigid central portion and each end portion. The rigid central portion, the opposed end portions, and the flexible portions define a variable cross section torsion bar with the flexible portions comprising reduced cross-sectional portions of the torsion bar relative to the rigid central portion and opposed end portions. Armature assemblies and torque motor valve actuators are also provided.

Abstract: A torque motor valve actuator includes a first magnetic pole piece, a second magnetic pole piece, an armature, and a coil. The first magnetic pole piece is of a first magnetic polarity. The second magnetic pole piece is of a second magnetic polarity, and is spaced apart from the first magnetic pole piece to define a gap. The armature is rotationally mounted and disposed in the gap between the first and second magnetic pole pieces. The coil surrounds at least a portion of the armature and is disposed such that it is not surrounded by either the first magnetic pole piece or the second magnetic pole piece. The coil is adapted to receive electric current and is configured, upon receipt thereof, to generate a magnetic force that causes the armature to rotate.

Abstract: A torque motor valve actuator includes a first magnetic pole piece, a second magnetic pole piece, an armature, and a coil. The first magnetic pole piece is of a first magnetic polarity. The second magnetic pole piece is of a second magnetic polarity, and is spaced apart from the first magnetic pole piece to define a gap. The armature is rotationally mounted and disposed in the gap between the first and second magnetic pole pieces. The coil surrounds at least a portion of the armature and is disposed such that it is not surrounded by either the first magnetic pole piece or the second magnetic pole piece. The coil is adapted to receive electric current and is configured, upon receipt thereof, to generate a magnetic force that causes the armature to rotate.