A variable pitch propeller assembly operatively coupled with an engine and methods for controlling the pitch of a plurality of propeller blades thereof is provided. In one example aspect, the variable pitch propeller assembly includes features for combining overspeed, feathering, and reverse functionality in a single secondary control valve. The secondary control valve is operable to selectively allow a controlled amount of hydraulic fluid to flow to or from a pitch actuation assembly such that the pitch of the propeller blades can be adjusted to operate the variable pitch propeller assembly in one of a constant speed mode, a feather mode, and a reverse mode.

A variable pitch propeller assembly operatively coupled with an engine and methods for controlling the pitch of a plurality of propeller blades thereof is provided. In one example aspect, the variable pitch propeller assembly includes features for combining overspeed, feathering, and reverse functionality in a single secondary control valve. The secondary control valve is operable to selectively allow a controlled amount of hydraulic fluid to flow to or from a pitch actuation assembly such that the pitch of the propeller blades can be adjusted to operate the variable pitch propeller assembly in one of a constant speed mode, a feather mode, and a reverse mode.

A system for controlling the modification of the pitch of the blades of a fan of a turbine engine, in particular for an aircraft. The turbine engine comprising blades mounted radially in a drive shaft and a setting device configured to modify the pitch of the blades on the basis of an axial force applied to said setting device. The control system comprises a hydraulic actuator, a hydraulic pump, a connecting ring connected mechanically to the hydraulic pump such that the flow rate of the hydraulic pump is proportional to the relative speed between the drive shaft and the connecting ring, and a magnetic coupling device designed to control the drive speed of the connecting ring in order to control the pitch of the blades independently of the speed of the drive shaft.

A propeller blade angle control circuit for a turboprop engine includes a propeller control unit controlling a supply of oil to modify an angle of propeller blades, a pump located upstream of the propeller control unit and providing the supply of oil from an engine oil return system to the propeller control unit, and a flow regulator between the pump and the propeller control unit, the flow regulator modulating a supply of oil to the propeller control unit. A bypass, downstream of the pump in the propeller blade angle control circuit, has an inlet fluidly coupled to the pump. The bypass is operable between a closed position and an open position in which a portion of the oil supplied to the propeller control unit is diverted away from the propeller blade angle control circuit. The open position is engaged when an oil pressure reaches a predetermined threshold.

A rotor blade control system includes a main control valve having an inlet for receiving liquid and an outlet for issuing liquid to a rotor pitch change actuator. The main control valve is configured to control flow of liquid from the inlet to the outlet to modify pitch angle of rotor blades. A feathering system has a first conduit in fluid communication with the outlet of the main control valve, a second conduit in fluid communication with the rotor pitch change actuator, and a drain conduit in fluid communication with a liquid return system. The feathering system has a normal operation mode for supplying liquid from the main control valve to the rotor pitch change actuator, and a feathering mode for allowing drainage from the rotor pitch change actuator to the drain conduit across a range of flow rates.

A variable pitch fan for gas turbine engine is provided. The variable pitch fan includes a plurality of fan blades rotatably coupled to a disk and an actuation assembly for changing a pitch of each of the plurality of fan blades. The actuation assembly generally includes an actuation member operably connected to at least one of the plurality of fan blades and a pin. The pin is movable between a first position in which the pin is positioned at least partially in a channel defined in the actuation member, and a second position. The pin blocks movement of the actuation member relative to the pin past a range defined by the channel when in the first position. The actuation assembly further includes a retraction system for selectively engaging the pin in moving the pin from the first position to the second position.

An actuation system is provided for varying the pitch of the blades of a variable pitch fan or propeller. The actuation system includes a first actuator and a second actuator. The actuation system further includes a first linkage which operably connects the first actuator to the blades such that operation of the first actuator varies the pitch of the blades via the first linkage. The actuation system further includes a second linkage which operably connects the second actuator to the first actuator such that operation of the second actuator varies the pitch of the blades by series connection of the second linkage to the first linkage.

An actuation system is provided for varying the pitch of the blades of a variable pitch fan or propeller. The actuation system includes a first actuator and a second actuator. The actuation system further includes a first linkage which operably connects the first actuator to the blades such that operation of the first actuator varies the pitch of the blades via the first linkage. The actuation system further includes a second linkage which operably connects the second actuator to the first actuator such that operation of the second actuator varies the pitch of the blades by series connection of the second linkage to the first linkage.

A device for controlling a propeller, having variable-pitch blades, of a turboprop engine, has a first hydromechanical device for controlling the pitch of the blades of the propeller and a second hydromechanical device for controlling the speed of rotation of the propeller. The device includes a single electromechanical actuator with a movable actuator member mechanically connected both to the first hydromechanical device for controlling the pitch, in order to manage the pitch setpoint, and to the second hydromechanical device for controlling the speed, in order to manage the speed setpoint.

A device for controlling a propeller, having variable-pitch blades, of a turboprop engine, has a first hydromechanical device for controlling the pitch of the blades of the propeller and a second hydromechanical device for controlling the speed of rotation of the propeller. The device includes a single electromechanical actuator with a movable actuator member mechanically connected both to the first hydromechanical device for controlling the pitch, in order to manage the pitch setpoint, and to the second hydromechanical device for controlling the speed, in order to manage the speed setpoint.