A system and method for determining a position of a feedback ring of a propeller of an aircraft engine are provided. The feedback ring is coupled to the propeller to rotate with the propeller and to be displaced along a longitudinal axis with adjustment of a blade angle. An engagement member is configured to engage the feedback ring and to be displaced along a longitudinal direction substantially parallel to the longitudinal axis with displacement of the feedback ring. A sensor comprises a first member coupled to the engine and a second member coupled to the engagement member. The second member is moveable relative to the first member along the longitudinal direction as the engagement member is displaced. The sensor generates a signal indicative of a longitudinal position of the second member relative to the first member. A controller determines an axial position of the feedback ring from the sensor signal.

A measurement system for determining an angular position of a component of a gas turbine engine includes one or more proximity sensors positioned at a fixed structure of the gas turbine engine and one or more sensor targets positioned at a rotatable component of the gas turbine engine. Each sensor target of the one or more sensor targets includes a target surface having a variable distance between the target surface and the proximity sensor with rotation of the rotatable component about a component axis of rotation. A measurement of distance between the proximity sensor and the target surface as measured by the proximity sensor is indicative of an angular position of the rotatable component relative to the component axis of rotation.

A fan of a turbine engine includes a disc provided with blades at the periphery thereof, the blades being mounted so as to pivot on the disc about a pivot axis, and a mechanism for changing the pitch of the blades. The mechanism is configured to adjust an angular position of each blade around the pivot axis. The angular position is in an angular setting range no greater than 20.

A variable vane assembly may comprise a first vane and a second vane. The first vane may comprise a first strut portion and a first flap portion. The first flap portion may be configured to pivot relative to the first strut portion. The second vane may comprise a second strut portion and a second flap portion. The second flap portion may be configured to pivot relative to the second strut portion. The first flap may be configured to pivot independently of the second flap.

An after-fan system for a gas turbine engine includes a variable pitch fan exit guide vane array. An after-fan turbine downstream of the variable pitch fan exit guide vane array and a control operable to vary a pitch of the variable fan exit guide vane array. A method of generating thrust for a gas turbine engine includes rotating a fan section with an array of fan blades; rotating an after-fan turbine downstream of the fan section; and varying a pitch of a variable fan exit guide vane array downstream of the fan section and upstream of the after-fan turbine.

A variable pitch fan assembly includes variable pitch fan blades circumscribed about engine centerline axis coupled to a drive shaft centered about the engine centerline axis. Each blade pivotable about pitch axis perpendicular to centerline axis and having blade turning lever connected thereto. One or more linear actuators non-rotatably mounted parallel to engine centerline axis and operably linked to fan blades for pivoting fan blades and connected to spider ring through thrust bearings for transmission of axial displacement of non-rotatable actuator rods of actuators while the fan blades are rotating. Spider arms extending away from spider ring towards blade roots and each spider arm connected to one of the turning levers. Turning levers may be connected and caromed to spider arms by pin and slot joint. Each spider arm may include joint pin disposed through joint slot of turning lever. Joint slot may be angled or curved.

A hub for a propeller having variable-pitch blades for a turbomachine with longitudinal rotation axis, including a plurality of blade platforms, each one being designed to receive a blade root, the platforms being distributed around the annular outer periphery of the hub concentrically with the longitudinal rotation axis, wherein each blade platform has the general geometric shape of a spherical cap, and wherein, between two adjacent blade platforms around the longitudinal rotation axis, the transverse dimension, in particular the diameter, of the hub can vary axially and radially.

A pitch actuating system for a turbomachine propeller including an actuator having a movable portion configured to be connected to propeller blades for displacement thereof in rotation with respect to the pitch axes of the blades. A first pitch control system for the blades, includes a first transmission screw movable in rotation, a first nut traversed by the first transmission screw and configured to cooperate with the blades for their displacement, an auxiliary system for feathering the blades, which comprise a second fixed transmission screw, a second nut traversed by the second transmission screw and movable in translation on the second nut, and wherein the pitch actuation system is configured so that a translational movement of the second nut causes a translational movement of the first transmission screw.

A pitch actuation system for a turbine engine propeller includes an actuator with movable part configured to rotate the blades of the propeller relative to the blade pitch axes. The actuator includes a transmission screw that is rotatable and movable in translation along a longitudinal axis, and a nut that engages the screw to move in translation along the longitudinal axis to adjust the pitch of the propeller blades. The actuator further includes non-rotatable decoupler for decoupling the rotation between the propeller and the nut. A blade feathering device has at least one electric drive motor and is configured to translate a member along the longitudinal axis. A blade pitch control device includes at least one electric motor configured to drive a rotor about the longitudinal axis, wherein that rotation rotates the screw and transmits translation of the member.

Apparatus for actuating and controlling the rotation, about their longitudinal axis (Y-Y), of blades (20) of cooling fans (10) for operating machines and/or vehicles, in particular agricultural tractors and off-road vehicles, said fan being mounted on a hub (11) which can be rotationally driven about its axis (X-X) by associated driving means (3,3a) suitable for connection to the heat engine (1) and mounted on a fixed support (5) by means of a bearing (3b) the apparatus comprising a ring (71) provided with a radial seat (71a) inside which a radial pin (72), eccentrically engaged in a base (73) integral with the shank (20a) of the blade (20), is inserted; an electric motor (30) which is coaxial with the axis (X-X) of the hub (11) and the shaft (31) of which is coaxially connected to a reduction gear (40), the kinematic output element (143) of which is coaxially connected by means of a screw (51a)/female thread (76a) coupling to a slider (76) displaceable in both directions along the axis (X-X) and kinematically connected to the ring (71) with an eccentric pin (72) driving the base (73) of the shank of the blade, an electromagnetic clutch (80; 180; 280) being arranged between the pulley (3) and the hub (11) of the fan.