Blade pitch

About: Blade pitch is a research topic. Over the lifetime, 5321 publications have been published within this topic receiving 63134 citations.

Rotary wing system

Abstract: A ROTARY WING SYSTEM FOR AIRCRAFT WHICH COMPRISES A RATATABLY MOUNTED HUB, AND A PLURALITY OF BLADES EACH CONNECTED TO THE HUB FOR ROTATION THEREWITH BY A RESPECTIVE BALL JOINT TO PERMIT MOVEMENT ABOUT THREE COORDINATE AXES INCLUDING THE LONGITUDINAL AXIS OF THE BLADE. BLADE PITCH CONTROL MEANS ROTATABLE WITH THE HUB IS CONNECTED TO THE BLADES TO HOLD EACH BLADE IN PREDETERMINED POSITION WITH RESPECT TO ITS LONGITUDINAL AXIS AS THE BLADES ARE ROTATED. THE BLADE PITCH CONTROL MEANS IS LONGITUDINALLY SPACED FROM THE HUB AND MOUNTED FOR RECIPROCABLE MOVEMENT IN A PLANE PARALLEL TO THE LONGITUDINAL AXIS OF THE HUB. THE BLADE PITCH CONTROL MEANS INCLUDES A LINKAGE CONNECTED TO EACH BLADE AT A POINT SPACED FROM THE BLADE''S BALL JOINT CONNECTION TO THE HUB AND SPACED FROM THE LONGITUDINAL AXIS OF THE BLADE.

Pitch control mechanism for bladed rotor

Abstract: Two Z-crank mechanisms connect at different stations to a rotor swashplate so that translation of the mechanisms causes collective pitch variation of the blades and so that rotation of the mechanisms either together or separately causes cyclic pitch variations of the blades.

Individual blade control system for helicopters

Abstract: A control system for providing individual blade control inputs to a four-bladed helicopter rotor. Limited authority series actuators located in a non-rotating portion of the helicopter are driven by a computer which receives inputs from individual blade sensors and aircraft stabilization sensors, summed with cockpit control inputs, and the resultant motions transmitted to the rotor blades through a conventional swashplate which drives four blades of the rotor and a translatable differential sleeve and summing linkage which drives only two blades. The differential sleeve is adapted for axially raising or lowering the swashplate. The combined motion of swashplate and differential sleeve is shown mathematically to result in individual blade control in pitch. Computer individual blade commands are converted from the rotating reference frame to cyclic, collective and differential blade pitch commands in the fixed reference frame through a coordinate transformation matrix.

Methods and systems for removing and/or installing wind turbine rotor blades

Abstract: A method for removing a rotor blade from a wind turbine may generally include installing a blade sock around an outer perimeter of the rotor blade, coupling a support cable to the blade root, lowering the rotor blade relative to the hub using the support cable, coupling at least one pulley cable between the rotor blade and a winch using at least one pulley, moving the pulley cable relative to the pulley to lower the rotor blade relative to the hub, applying a force through the blade sock as the pulley cable is moved relative to the pulley in order to control an orientation of the rotor blade and further lowering the rotor blade to a location on or adjacent to the support surface.