Abstract: A variable blade pitch wind turbine and method of passively varying the blade pitch is presented. Each blade of the turbine rotor can individually and passively rotate about a respective blade axis to continuously vary the pitch of the blades to adjust to the ever changing wind speed and direction without active controls or other mechanical or electrical induced inputs to force rotational movement of the blades. Sections of each blade can respectively rotate to change the blade twist. In one example, a second rotor is used to increase the electrical generation and efficiency of the blade turbine.

Abstract: A rotor hub has a yoke with radial arms allowing flapping of connected blades about a flap axis. A grip is rigidly attached to each blade, and a lead-lag bearing connects each grip to one of the arms, the bearing defining a lead-lag axis outboard of the flap axis. Each arm has a pair of straps located on opposite sides of the rotor plane for transferring centrifugal force from the blades to the central portion of the yoke. A pair of lead-lag dampers is provided for each grip, the dampers of each pair being located on opposite sides of the rotor plane and connecting an inboard end portion of the grip to the adjacent strap. In-plane motion of a blade causes rotation of the attached grip about the lead-lag axis, causing opposite motion of an inboard end portion of the grip. The dampers act to oppose rotation of the grip.

Abstract: A stiff in-plane gimbaled rotor head for a rotorcraft, such as a helicopter, includes a vertically extending rotor shaft, a center hub disposed on the rotor shaft for conjoint rotation therewith, and an outer hub surrounding the center hub and coupled thereto through a spherical gimbal bearing for conjoint rotation therewith, and such that the outer hub is also capable of an angular range of gimbaling movement relative to the center hub. A plurality of rotor blades, which may include three or more blades, is coupled to the rotor shaft through the inner and outer hubs by a constant velocity joint that enables the blades to be rotated in a common plane about the axis of the rotor shaft while controlling the respective pitches of the blades and such that any other relative in-plane and out-of-plane movements of the blades during rotation is prevented.

Abstract: The rotary damper for controlling helicopter motions includes an outer canister with an inner paddle wheel receiving cavity which receives an inner paddle wheel with upper and lower elastomeric tubular intermediate members between the inner paddle wheel and the outer canister. The canister and inner paddle wheel form neighboring variable volume chambers in liquid communication through liquid damping conduits. A clockwise rotation of the inner paddle wheel about the center of rotation axis relative to the outer canister pumps damper liquid from a second variable volume chamber through a first liquid conduit towards a first variable volume chamber, and a counterclockwise rotation of the paddle wheel relative to the outer canister pumps the damper liquid from the first variable volume chamber through the first liquid conduit towards the second variable volume chamber with the elastomeric tubular intermediate members providing for the relative rotation and containing the damper liquid in the damper.

Abstract: A combined ceiling fan and light fitting (fan/light) (1) having folding fan blades (12) is provided. The fan light (1) has a blade support (13) arranged to be rotated by an electric motor (6), with blades (12) being secured to the blade support (13), a root end of each blade (12) being pivotable between folded and operative positions about a blade pivot axis-(14) fixed in the blade support (13). In one aspect of the invention, an improved mechanism is provided for synchronizing movement of the blades. This uses a sun gear (16) mounted to the blade support and arranged to mesh with planet gears (17) that rotate about the blade pivot axes (14). In addition improvements are provided to blades (12, 33, 60) and blade mounting arrangements that balance compact folding of the blades (12, 33, 60) and good air moving effectiveness.

Abstract: A fan device having simultaneously foldable blades includes a rotatable driving unit. A plurality of supporting frames extend outwardly from the driving unit, each supporting frame has a pivot mounted on one end thereof. A plurality of shells are respectively mounted on the supporting frames, each shell has a center hole defined therein. A plurality of blades are respectively disposed on the shells. Each blade has an assembling portion disposed thereon. Each assembling portion has a through hole defined therein. A plurality of coupling rods respectively positioned between every two adjacent shells. When the driving unit rotates, the shells synchronously rotate and driving the coupling rods to be moved for simultaneously driving the blades to retractably fold/unfold.

Abstract: Wind turbine comprising one or more blades, incorporating in each blade a damping device comprising a first damping element tuned at the main resonance frequency of the blade ? o and K additional damping elements tuned at frequencies ? 1, ? 2, . . . ? k so that in the event of blade vibrations its amplitude A is reduced in a percentage Y of the amplitude Ao at the main resonance frequency of the blade ? o in a band extended above and below the main resonance frequency of the blade ? o in a percentage X of ? o, said frequencies ? 1, ? 2, . . . ? k being comprised within said band.

Abstract: A blade support limb structure of a vertical axis wind power generator includes a fixed support limb (1) and a rotatable support limb (2), one end (21) of the rotatable support limb is connected with one end (22) of the fixed support limb and the rotatable support limb may rotate around it. The structure keeps a wind wheel at stable rotation speed in the case the environmental wind speed exceeds the rated wind speed, thereby to ensure that vertical axis wind power generator outputs constant power. The structure solves a problem of constant power output of the vertical axis wind power generator from hundreds watts to thousands watts, so its applications are wide.

Abstract: A wind turbine system includes a shaft, a rotor for driving the shaft, and a first fluidic teeter control assembly. The rotor includes a first blade engaged to the shaft by a hub, and has a degree of freedom to pivot relative to the shaft. A first teeter angle is defined between an instantaneous position of the first blade and a time-averaged plane of rotation of the first blade. The first fluidic teeter control assembly is engaged between the rotor and the shaft for providing a first dynamic teeter restraining force as a function of the first teeter angle and a fluidic resistance. The first dynamic restraining force is relatively low when the first teeter angle is within a first teeter operation range, and the first dynamic restraining force is higher when the first teeter angle is outside that range.

Abstract: A ring element for a turbomachine, in particular for an aircraft gas turbine, is disclosed. The ring element has a ring element main body that has two adjacently arranged ring ends, the ring ends being connected to one another in a form-locking manner with respect to an axial plane. Also disclosed is a turbomachine having at least one such ring element.

Abstract: A method of counteracting a rotor moment of one or more rotors of a concentric dual-rotor helicopter includes sensing angular velocity and angular acceleration of a helicopter during a flight maneuver. The angular velocity and angular acceleration are compared to a set of control parameters and one or more control servos change the cyclic pitch of the one or more rotors to counteract the rotor moment. A control system for counteracting a rotor moment of one or more rotors of a concentric dual-rotor helicopter includes one or more sensors configured to sense angular velocity and angular acceleration of a helicopter during a flight maneuver. A computer is operably connected to the one or more sensors and configured to compare sensor data to a set of control parameters. A plurality of control servos change the cyclic pitch of the one or more rotors to counteract the rotor moment.

Abstract: A rotor damper for a tail rotor of a helicopter. A main body of a resilient material is to be arranged between a drive shaft for the tail rotor and a hub on which rotor blades for the tail rotor are coupled. A flange is connected to the main body of the rotor damper. The flange includes an abutment surface for abutting an outer surface of the hub. A tail rotor including the rotor damper.

Abstract: A frequency-dependent damper for creating a damping force in response to a variable-frequency disturbance includes an outer damper body having an internal cavity, an inner damper body for receiving the variable-frequency disturbance extending into the internal cavity, a first fluid chamber and a second fluid chamber defined inside the internal cavity, a piston separating the first and second fluid chambers, a selected orifice for transferring fluid between the first and second fluid chambers, and a selected spring element arranged serially between the piston and the inner damper body such that the piston can move relative to the inner damper body through deformation of the spring element.

Abstract: A wind turbine includes a hub comprising at least three spaced projections and a hub cap; at least three blades each comprising a root plate at one end, the root plate including a sleeve having a hole on a windward side; at least three shaft members each interconnecting the root plate and a corresponding projection; at least three sets of four abutment plates each secured to either side of the root plate or either side of the projection; U-shaped steel torsion bars each having both ends at an inclined angle of about 15 to 25 degrees fastened in the abutment plate and disposing the root plate at an angle of about 4 to 10 degrees with respect to the corresponding projection; a spring put on the rotation shaft on a leeward side of the hub; and pins each installed in a hub cap and sticking into the hole.

Abstract: A helicopter rotor damper system including a torsional damper with a damper centering bearing providing a damper center of rotation axis, a first elastomeric torsional damper with a first elastomeric torsional damper torsional elastomer bonded between a first elastomeric torsional damper first torsional damper nonelastomeric bonding surface and a first elastomeric torsional damper second torsional damper nonelastomeric bonding surface, and a second elastomeric torsional damper with a second elastomeric torsional damper torsional elastomer bonded between a second elastomeric torsional damper first torsional damper nonelastomeric bonding surface and a second elastomeric torsional damper second torsional damper nonelastomeric bonding surface.

Abstract: A wind turbine active damping arrangement for damping forces exerted on a component connected to a main shaft of a wind turbine is proposed. The damping arrangement comprises a smart fluid damper and a control device for controlling a field generator of the smart fluid damper to control the extent of damping according to a performance parameter of the wind turbine. The smart fluid damper comprises a closed chamber containing a smart fluid and a piston. The piston travels along a direction in the chamber and comprises a channel through which the smart fluid can flow. The smart fluid damper comprises a field generator for generating a field across the smart fluid and an input for a field generator control signal for controlling the field generator to alter the field according to the performance parameter of the wind turbine.

Abstract: A turbomachine vane damper constructed so as to be housed between the lower face of the platforms of two adjacent turbomachine vanes and the rim of the rotor disk on which the vanes are mounted is disclosed. The damper includes a weight, a bearing plate and a spring. The spring connects the weight to the bearing plate.

Abstract: A rotary wing system with a troublesome motion when rotating about a rotation axis, including a fluid tubular damper with a damper fluid for controlling the troublesome motion. The damper has an inboard and an outboard end, the inboard end attached to a rotary wing system inboard member proximate the rotation axis and the outboard end attached to a rotary wing system outboard member. The damper is terminated with a nonelastomeric end cap and contains damper fluid in at least an inboard and an outboard variable volume nonelastomeric working chamber which is worked by a nonelastomeric damper piston and a relative motion between the rotary wing system members. The damper includes a dynamically variable elastomeric volume compensator chamber in fluid communication with the working chambers, with the communication a controlled communication with the fluid flowed through control valves towards the working chambers.

Abstract: The present invention relates to an improvement to rotorcraft rotors (1) fitted with inter-blade drag dampers (15) such that for each blade (4), the two joints (16) connecting said blade (4) to two inter-blade drag dampers (15) are disposed on either side of the pitch variation axis (101) of said blade, at least one of the two joints (16) being offset to above the plane P containing the pitch variation axis (101) and the vertical flapping axis (102).

Abstract: A vertical-axis wind turbine for use with an electrical generator for producing power by converting the energy of wind currents into mechanical rotational energy which is then used to operate the electrical generator. In an embodiment, a rotor is responsive to wind currents by imparting rotation upon a central vertical shaft. Preferably, the rotor is designed with functional curved surfaces for efficient operation.

Abstract: A damping system for damping vibrations of a rotor blade of a rotor of a turbomachine is disclosed. A damping element is guided on a support such that the damping element is radially outwardly movable during a rotation of the rotor and is contactable with a lower platform area of a rotor blade. A circumferential contact surface is formed by an elevation on the lower platform area, where the circumferential contact surface is a limit stop for a movement of the damping element.

Abstract: A lift-type wind turbine having a substantially vertical rotating shaft and a plurality of substantially vertical blades secured to the shaft. Each blade includes a front portion, a rear portion, and a pivot axis pivotally securing the rear and front portions. The rear portion pivots relative the front portion. The blades additionally include bottom and top edges positioned on each of the front portions. Each bottom edge is arranged substantially equidistant from the shaft proximate a first circumference extending substantially horizontally about the shaft, whereas each top edge is arranged substantially equidistant from the shaft proximate a second circumference extending substantially horizontally about the shaft. The blades are angled relative to the rotating shaft. The blades have an open, drag means position as well as a closed, lift means position, and passively switch between the positions based on wind speed for efficient rotation.

Abstract: A wind turbine for generating electricity has been developed. The turbine includes a housing for securement to a support. A wheel is mounted within the housing and is rotatable about a horizontal axis. The wheel has an axle assembly and a number of blade assemblies affixed thereto. Each of the blade assemblies has a frame with a spaced-apart pair of uprights and a crosspiece connecting the uprights. Each of the blade assemblies also having a pair of movable blades positioned within the frame with each of the blades being hingedly fastened to a respective one of the uprights. A brake actuator assembly is associated with each of the blades for relieving pressure imparted by strong winds on the blades. A brake operator assembly, disposed principally within said axle assembly, synchronizes the movement of the blades. An electrical current generator is connected to the wheel so as to be powered thereby.

Abstract: The lifetime of plural shock absorbing resilient inserts of an adjustable pitch propeller with feathering blades may be increased. According to an embodiment, stops are implemented between metal surfaces that may be reached only in the event of shocks of great violence and following a certain elastic deformation of the shock absorbing inserts, which remain partially compressed. At the bottom of each circular cavity housing a respective annular insert of elastomer of the flange of a first cylindrical sleeve directly keyed on the drive shaft of the propeller a hole coaxial and of greater diameter than the diameter of a central hole of the annular insert and of the relative engaging pin is formed. Pins projecting from the face of the terminal flange of a second circular sleeve extend through the coaxially formed holes at the bottom of the respective circular cavities of the flange of the first sleeve.

Abstract: A vertical axis wind turbine comprising: a rotatable vertical shaft; a first horizontal shaft attached to the vertical shaft, and extending on either side of the vertical shaft; a first wind turbine blade fixedly attached to the first horizontal shaft, the first wind turbine extending in a generally perpendicular direction from the first horizontal shaft; a second wind turbine blade fixedly attached to the first horizontal shaft, the second wind turbine blade extending in a generally perpendicular direction from the first horizontal shaft, the second wind turbine blade fixed at an operational angle with respect to the first wind turbine blade; a first and second motion limiting means attached to the vertical shaft, where each motion limiting means extends into the rotational travel of a turbine blade.

Abstract: A turbine with vanes and tethers that adjust to the wind includes: an axle, adapted to be positioned perpendicular to the airflow; a radial spar attached to the axle; a vane rotatably attached to the spar; and a positioning element to limit the vane from rotating substantially more than a perpendicular angle away from the spar. The device retains the vane in a position that utilizes the airflow to rotate the axle. The positioning element is a tether attached to the distal point of the vane.

Abstract: An assembly for providing flexure to a blade of a rotary blade system includes an upper support plate having an upper curved surface, a lower support plate having a lower curved surface, and a yoke positioned therebetween. At least one of the upper and lower yoke surfaces has a layer of cushioning material positioned thereon and secured thereto. An alternate embodiment includes an assembly for providing flexure to a blade of a rotary blade system, including, an upper support plate having an upper curved surface, a lower support plate having a lower curved surface, and a yoke positioned therebetween and directly contacting the support plates wherein one of the curved surfaces is a non-circular arc that does not form part of the circumference of a circle. Another alternate embodiment includes a similar assembly having a twist-shank type of yoke for providing rotation of attached blades about their respective pitch axes.

Abstract: The invention relates to a wind power plant, comprising a rotor that can be rotated about a vertical axis, said rotor between two horizontal bearing planes disposed at a distance on top of each other comprising a plurality of rotor blades, which are disposed distributed on a circumferential circle, can each be pivoted about a vertical pivot axis, and the pivot range of which is delimited on both sides by a stop. In such a wind power plant, an improvement in the energy yield, while simultaneously ensuring another operation, is enabled in that the width of the rotor blades is smaller than approximately ? the radius of the circumferential circle.

Abstract: A rotor hub assembly for a rotary-wing aircraft has a central member and a plurality of blade grips adapted for attaching rotor blades to the central member. The blade grips are pivotally attached to the central member and are capable of pivoting about a pivot axis generally normal to a plane of rotation of the blades. The pivoting allows for in-plane motion of the blades relative to the central member. A damper is operably connected to each blade grip for damping the in-plane motion of the associated blade, each damper being selectively switchable between at least two spring rates.

Abstract: A wind driven energy source is providing utilizing a turbine wheel comprising a peripheral rim attached to a central hub via a series of spokes. A plurality of airfoil blades are assembled to the wheel, each blade being secured to a pair of spokes and positioned proximate an interior edge of the rim and extend only partially down the length of the spoke. This provides a central opening allowing airflow through the innermost region of the wheel. The blades are pivotally assembled to the spokes and can include an incident angle adjusting mechanism as well as a breakaway feature.

Abstract: A design for a scalable advanced design vertical shaft wind turbine power generator which incorporates a superior symmetrical blade configuration and a unique blade mounting approach which utilizes aerodynamic forces to provide wide changes in blade positions o optimize efficiency and eliminates the need for expensive mechanical control devices while minimizing manufacturing, operational and maintenance costs.

Abstract: A rotor for a helicopter, having a drive shaft rotating about a first axis; a hub angularly integral with the drive shaft about the first axis; and at least two blades projecting from the hub, on the opposite side to the first axis, and extending along respective second axes crosswise to the first axis; each blade is movable with respect to the hub and the other blades about a respective fourth axis parallel to the first axis, about the respective second axis, and about a respective third axis crosswise to the first and respective second axis; the rotor also has a number of first dampers for damping vibration associated with at least oscillation of the relative blades about the respective fourth axes; the first dampers are connected to one another and each to a relative blade; and, in a radial direction with respect to the first axis, at least one first damper is located between the first axis and the fourth axis of the relative blade.

Abstract: In the absence of centrifugal force produced during rotation of helicopter blades, damage may result if a blade is rotated upward by wind or other forces. Lock units removably appended between the rotor assembly and each blade pitch housing attached to a helicopter blade are usable to restrict upward rotation. A base portion of a lock unit may be configured to be held in position by a removable pin device. An extendible device extending from the base portion to a surface of a blade pitch housing can be adjusted to press the base portion back against a surface of the rotor assembly. The lock unit thereby restricts these surfaces of the blade pitch housing and rotor assembly from moving closer to each other and thereby restricts upward rotation of the blade pitch housing and its attached helicopter blade. The lock units are readily removable in preparation for returning a helicopter to active use.

Abstract: A wind turbine, having: (a) a rotatable frame; (b) a plurality of first air panels mounted to the rotatable frame, the plurality of first air panels extending in a direction parallel to an axis of rotation of the rotatable frame; (c) a plurality of second air panels mounted to the rotatable frame, the plurality of second air panels extending in directions radial to the axis of rotation of the rotatable frame; and (d) a base shaped to direct air flow received from a direction radial to the axis of rotation of the rotatable frame into a direction parallel to the axis of rotation of the rotatable frame.

Abstract: A method for limiting blade pitch is provided. The method includes providing a brake assembly that is actuatable to limit blade pitch, providing a limit stop assembly including a stop wheel and a traveler movable relative to the stop wheel, and coupling the limit stop assembly to the brake assembly such that the limit stop assembly actuates the brake assembly when the traveler engages the stop wheel.

Abstract: The invention teaches a turbine capable of receiving wind power and transferring wind power into mechanical energy, and capable of coupling with a generator. The turbine includes a generally flat horizontally mountable support plate capable of rotation about a central axis, the support plate having a plurality of pivot modifications located proximate to an outside circumference, and vanes coupled to the support plate at the pivot modification, each vane having a vane shaft coupled between a pivot modification on the first support plate and a pivot modification on a cap plate, each vane supported by a first rib and a second rib having an exterior edge defined as the exterior circumference edge of the head and the interior circumference edge of the tail, and a material attached between the exterior of the first rib and the exterior of the second rib.

Abstract: An assembly for providing flexure to a blade of a rotary blade system, the assembly including an upper support plate having an upper curved surface, a lower support plate having a lower curved surface, and a yoke positioned therebetween. At least one of the upper and lower yoke surfaces having a layer of cushioning material positioned thereon and secured thereto. The layer of cushioning material extending along and following the general contour of yoke surface, and the layer of cushioning material directly contacting a support plate. Another embodiment is an assembly for providing flexure to a blade of a rotary blade system, including, an upper support plate having an upper curved surface, a lower support plate having a lower curved surface, and a yoke positioned therebetween and directly contacting the support plates wherein one of the curved surfaces is a non-circular arc that does not form part of the circumference of a circle.

Abstract: A sculpted throat spool of a tension-torsion strap assembly is disclosed. Using the sculpted throat spool minimizes the stress riser typically present at the edge of the spool when a tension-torsion strap is articulated.

Abstract: Described is a blade (10) extending longitudinally from a root (11) of the blade (10) to a free end (12) of the blade (10), the blade (10) being provided with an incorporated resonator (20) for reducing the drag movements (F1, F2) of the blade (10), the resonator (20) being provided with a closed tank (30) that is partially filled with a liquid (50). Furthermore, the resonator (20) includes a central tube (40) immersed inside the tank (30), the tank (30) and the central tube (40) being arranged in a longitudinal direction (Y) of the blade (10), the central tube (40) having first and second ends (41, 42) that communicate with the tank (30) so that the liquid (50) can move from the tank (30) into the central tube (40), and vice versa.

Abstract: An adjusting apparatus (9) for adjusting the pitch angle of propeller blades (1, 2, 3, 4, 5, 6, 7, 8) of a variable-pitch propeller • in a first blade pitch-angle range with positive pitch angles at which the propeller blades (10) produce thrust, • in a second blade pitch-angle range, • in a third blade pitch-angle range with negative pitch angles, at which the propeller blades produce reverse thrust with the propeller rotating in the same direction, with the second blade pitch-angle range being a pitch-angle intermediate range located between the first and the second blade pitch-angle range, which includes the pitch-angle range in which the blade drag is a minimum, as well as a range of positive pitch angles with low thrust and a range of negative pitch angles with low reverse thrust, and with the adjusting apparatus being able to provide adjustment of the propeller blades (1, 2, . . .

Abstract: A wind driven power system employing multiple arms adapted to rotate about a central structure, each arm having a series of panels pivotally connected thereto and adapted to open and close as the system rotates to perpetuate the rotational movement and to produce energy.

Abstract: The invention relates to a rotorcraft rotor comprising a hub and at least two blades hinged relative to the hub about respective pitch axes and about respective flap axes, and about respective lag axes; each blade is secured to a respective pitch lever; the rotor includes a respective pitch control rod connected to each pitch lever by a first ball joint, and a common lag damper system centered substantially on the axis of rotation of the rotor and connected to each of the blades; the damper system is secured to a respective lateral projection from each blade via a respective second ball joint that is sufficiently close to the first ball joint connecting the pitch rod to the pitch lever for the lag damper system to be relatively insensitive to flap oscillations of the hinged blades.

Abstract: The Prentice Wind Engine will operate 100% from “wind power” from any direction to produce both air pressure as well as hydraulic pressure at the same time to work together to generate electricity. In the case of the Prentice Wind Engine, assuming that the wind is coming from the north direction, panel #1 is facing north in the closed position and receives the full force from the north wind. As it rotates, the wind spills out and air and gravity push the panel away from its based hinged position and in doing so, produces two functions, wind force from its rotation and pressure force from the hydraulic cylinder. As it proceeds through the 360° circle it gradually “feathers” back to its first closed position, ready to repeat the sequence, and the other wind panels follow the same sequence. Also, these units can be stacked one above the other to function as one unit.

Abstract: A rotor system includes a multiple of rotor blade yokes mounted to a rotor hub. A lead/lag damper is mounted to each of the rotor blade yokes and to a damper hub. An actuator system is operable to shift a damper hub axis of rotation relative the rotor axis of rotation to minimize 1P damper motions. A method of minimizing 1P damper motions within a rotor system includes shifting the damper hub axis of rotation relative the rotor axis of rotation to oscillate an inner connector of each lead/lag damper in phase with a 1P blade motion to minimize the 1P motion of the damper.

Abstract: A helicopter rotor damper system including a torsional damper with a damper centering bearing providing a damper center of rotation axis, a first elastomeric torsional damper with a first elastomeric torsional damper torsional elastomer bonded between a first elastomeric torsional damper first torsional damper nonelastomeric bonding surface and a first elastomeric torsional damper second torsional damper nonelastomeric bonding surface, and a second elastomeric torsional damper with a second elastomeric torsional damper torsional elastomer bonded between a second elastomeric torsional damper first torsional damper nonelastomeric bonding surface and a second elastomeric torsional damper second torsional damper nonelastomeric bonding surface.

Abstract: Tidal forces used for generation of electrical power has long been a solution to a recognized need. A really practical device to convert the energy of the fluid flow through tidal inlets into electrical power is the subject of this invention.

Abstract: A vertical-axis turbine is provided, which comprises two or more arc-shaped blades which can pivot so as to decrease drag and maximize the force collected by each blade from moving gas or liquid. These arc-shaped blades can also be capable of directing moving gas or liquid from one blade to another. Additionally, these blades can comprise thin strips along their outer edge, which can increase their strength and rigidity as well as increase the amount of force captured by each blade from the moving gas or liquid.

Abstract: A rotorcraft rotor with hinged blades, includes: a hub; a plurality of blades hinged to flap relative to the hub; bottom abutments of the hub, and bottom abutments of the blades suitable for co-operating with the bottom abutments of the hub; and top abutments of the hub, and top abutments of the blades suitable for co-operating with the top abutments of the hub; the top abutments of the hub being movable between a deployed position in which they extend facing the top abutments of the blades, and a retracted position in which they are offset angularly away from the top abutments of the blades. The rotor also includes elements for locking the top abutments of the hub in the deployed position, and inertial means for releasing the top abutments of the hub and for deactivating the locking means.

Abstract: A fluid-driven turbine includes a main driving shaft defining a shaft axis and a plurality of blade sets symmetrically disposed about the main driving shaft. Each of the plurality of blade sets includes a rod extending radially from the main driving shaft in a direction transverse to the shaft axis. The rod defines a rod axis. Each blade set also includes a fluid-tiltable blade connected to the rod and extending along the direction of the rod axis. It has an airfoil shape in cross-section with a leading edge, a trailing edge, and a maximum thickness. The blade is divided into first and second moment-inducing sections located on opposite sides of the rod with the first moment-inducing section being greater in area than the second moment-inducing section. Also, it is rotatable about the rod axis between an optimum pressure-receiving position and a least fluid-resistance position for receiving fluid energy from variable directions.

Abstract: A droop stop mechanism for a helicopter rotor blade includes a pair of opposing stops disposed on opposite sides of the blade's flap hinge. An interposer is mounted at the end of an arm on a rotatable shaft for rotation in a plane perpendicular to the hinge. A torsion spring disposed concentrically about the shaft has a first end that is fixed and a second end coupled to the shaft to bias the interposer to a position disposed between the stops, thereby limiting blade droop. A weight is attached to the shaft such that, with rotation of the rotor, centrifugal forces acting on the weight cause the shaft and arm to rotate so as to overcome the bias of the spring and urge the interposer out from between the stops, thereby allowing greater blade droop. The spring and shaft are sealed in a canister for protection from the elements.