A pitch angle indicator system indicates a pitch angle of blades of a propeller of a marine propulsion unit. A mechanical link couples at least one of the blades to a first end of a first rod. An indicator is coupled to a second end of the first rod. The mechanical link is configured to convert a change in the pitch angle into a rotation of the first rod about its longitudinal axis. The indicator is configured to provide an indication of the amount of rotation of the first rod about the longitudinal axis.

A system and method for providing feedback for an aircraft-bladed rotor about a longitudinal axis and having an adjustable blade pitch angle. At least one position marker is provided at the rotor, extends along an axial direction, from a first end to a second end, and has varying magnetic permeability from the first end to the second end. At least one sensor is coupled to the rotor and configured for producing, as the rotor rotates about the longitudinal axis, at least one sensor signal in response to detecting passage of the at least one position marker. A control unit is communicatively coupled to the at least one sensor and configured to generate a feedback signal indicative of the blade pitch angle in response to the at least one sensor signal received from the at least one sensor.

In an apparatus for controlling an outboard motor mounted on a boat and having an internal combustion engine and a variable pitch propeller, characteristics defining a desired pitch angle of the propeller that makes fuel consumption minimum relative to a navigation speed of the boat are memorized and the pitch angle of the propeller is controlled to the desired pitch angle that is corresponding to the navigation speed detected by a navigation speed detector in accordance with the characteristics.

The object of the invention is a method and an apparatus in an electric propulsion arrangement of a sailing vessel, wherein the sailing vessel has a traction device provided with an electric motor and with a propeller mechanism, the electric motor of traction device is arranged to be used, if necessary, in forward drive and reverse drive as well as during sailing as a generator for charging the accumulators of the sailing vessel. The propeller mechanism comprises a propeller hub with blades, a hollow propeller shaft fixed at its first end to the propeller hub, a shaft controlling the pitch angles of the propeller blades, said control shaft rotating inside the propeller shaft, and a servomotor rotating the control shaft. The servomotor is fixed to the second end of the propeller shaft to be rotatable along with the propeller shaft.

There is provided a blade angle feedback system for an aircraft-bladed rotor rotatable about a longitudinal axis and having an adjustable blade pitch angle. A feedback device is coupled to rotate with the rotor and to move along the axis with adjustment of the blade pitch angle. The feedback device comprises a body having position marker(s) embedded therein, the body made of a first material having a first magnetic permeability and the position marker(s) comprising a second material having a second magnetic permeability greater than the first. Sensor(s) are positioned adjacent the feedback device and configured for producing, as the feedback device rotates about the axis, sensor signal(s) in response to detecting passage of the position marker(s). A control unit is communicatively coupled to the sensor(s) and configured to generate a feedback signal indicative of the blade pitch angle in response to the sensor signal(s) received from the sensor(s).

A feedback device for use in a gas turbine engine, and methods and systems for controlling a pitch for an aircraft-bladed rotor, are provided. The feedback device is composed of a circular disk and a plurality of position markers. The circular disk is coupled to rotate with a rotor of the gas turbine engine, to move along a longitudinal axis of the rotor, and has first and second opposing faces defining a root surface that extends between and circumscribes the first and second faces. The plurality of position markers extend radially from the root surface, are circumferentially spaced around the circular disk, and extending along the longitudinal axis from a first end portion to a second end portion. At least part of the first end portion and/or of the second end portion comprises a material having higher magnetic permeability than that of a remainder of the position markers.

There is provided a blade angle feedback system for an aircraft-bladed rotor rotatable about a longitudinal axis and having an adjustable blade pitch angle. A feedback device is coupled to rotate with the rotor and to move along the axis with adjustment of the blade pitch angle. The feedback device comprises a body having position marker(s) embedded therein, the body made of a first material having a first magnetic permeability and the position marker(s) comprising a second material having a second magnetic permeability greater than the first. Sensor(s) are positioned adjacent the feedback device and configured for producing, as the feedback device rotates about the axis, sensor signal(s) in response to detecting passage of the position marker(s). A control unit is communicatively coupled to the sensor(s) and configured to generate a feedback signal indicative of the blade pitch angle in response to the sensor signal(s) received from the sensor(s).

A feedback device for use in a gas turbine engine, and methods and systems for controlling a pitch for an aircraft-bladed rotor, are provided. The feedback device is composed of a circular disk and a plurality of position markers. The circular disk is coupled to rotate with a rotor of the gas turbine engine, to move along a longitudinal axis of the rotor, and has first and second opposing faces defining a root surface that extends between and circumscribes the first and second faces. The plurality of position markers extend radially from the root surface and are circumferentially spaced around the circular disk. The position markers have a top surface elevated with respect to the root surface and opposing first and second side surfaces. The side surfaces of the position markers have a curved concave profile extending toward the root surface.

There is provided a blade angle feedback system for an aircraft-bladed rotor rotatable about a longitudinal axis and having an adjustable blade pitch angle. A feedback device is coupled to rotate with the rotor and to move along the axis with adjustment of the blade pitch angle. The feedback device comprises a body having position marker(s) embedded therein, the body made of a first material having a first magnetic permeability and the position marker(s) comprising a second material having a second magnetic permeability greater than the first. Sensor(s) are positioned adjacent the feedback device and configured for producing, as the feedback device rotates about the axis, sensor signal(s) in response to detecting passage of the position marker(s). A control unit is communicatively coupled to the sensor(s) and configured to generate a feedback signal indicative of the blade pitch angle in response to the sensor signal(s) received from the sensor(s).

There is provided a blade angle feedback system for an aircraft-bladed rotor rotatable about a longitudinal axis and having an adjustable blade pitch angle. A feedback device is coupled to rotate with the rotor and to move along the axis with adjustment of the blade pitch angle. The feedback device comprises a body having position marker(s) embedded therein, the body made of a first material having a first magnetic permeability and the position marker(s) comprising a second material having a second magnetic permeability greater than the first. Sensor(s) are positioned adjacent the feedback device and configured for producing, as the feedback device rotates about the axis, sensor signal(s) in response to detecting passage of the position marker(s). A control unit is communicatively coupled to the sensor(s) and configured to generate a feedback signal indicative of the blade pitch angle in response to the sensor signal(s) received from the sensor(s).