Abstract: The windmill includes a vertically positioned support shaft, a plurality of elongated, molded arcuate plastic vanes which are vertically positioned and operatively connected to the support shaft, which vanes are slightly flexible so winds engaging the vanes will flatten the arc of some vanes and will make the arc of other vanes tighter to provide unbalanced rotational forces on the vanes, and means operatively connect to the shaft to provide power therefrom on shaft rotation.

Abstract: A composite rotor blade has a nose spar of fiber reinforced plastic with the fibers extending spanwise the length of the spar and at the root encircling a transverse hub attachment structure with the spar provided with a tubular inner liner of cross ply filament wound fiberglass forming a closure for the nose spar with a blad afterbody structure including skins for integrating the afterbody with the nose spar and liner. Preferably the spar has an inner liner and an outer liner both of cross ply filament wound fiberglass in multi layers. The blade afterbody structure includes honeycomb filler having cells extending in the direction of blade thickness.

Abstract: A wind turbine blade in the form of a semi-spar in which the outer portion of the finished blade shape is the filament wound spar itself and the remainder of the blade incorporates a trailing edge portion, increasing in dimension toward the blade base, this part of the blade being filament wound around the spar.

Abstract: A helicopter rotor blade is constructed at least in part of composite material of the type in which fibres (such as glass or carbon fibres) are embedded in a matrix. The stiffness in the flapping plane, the lagging plane, or both are modified at one or more positions along the blade to provide advantageous resonance frequencies. Modification of the stiffness is achieved by diverting a substantial number of fibres inwardly towards the relevant spanwise neutral bending plane.

Abstract: An article such as a blade fabricated from a plurality of high-strength, reinforcing filaments embedded in a matrix material and characterized by a portion of the filaments oriented transverse to the blade longitudinal axis in a direction through the blade to enhance transverse shear strength. In one embodiment, a plurality of columnar filament cores are each wrapped with a filament sheet and bonded together laterally to form the blade primary structure. The orientation of the filaments within the sheet forms an angle with the core longitudinal axes such that at least a portion of the sheet filaments runs transverse to the blade from one aerodynamic surface to the other. In an alternative embodiment, a blade is formed of a plurality of bonded filament laminates accordian folded with the fold lines angled with respect to the longitudinal axes of the filaments, the distance between fold lines being equal to or greater than the blade thickness.

Abstract: Disclosed is a multi-blade fan assembly and method for manufacture, the fan assembly having a central hub having means for being attached to a driving assembly and having a plurality of fan blades connected therewith and extending radially therefrom; and further characterized by having the fan blades manufactured in accordance with subcritical aerodynamic air foil criteria so as to be efficient for moving ambient air at low relative speeds between the fan blade assembly and the air and for minimum power consumption and noise at high relative such speeds. Each of the fan blades has a length to width ratio L/W within the range of 1-9; has a length L in the range of 6-18 inches; has an artificially reduced chord thickness to length ratio within the range of 0.03-0.12; has a chord that is totally contained within a perpendicular planar cross section of the blade at the chord location and has a twist for obtaining a substantially uniform flow of air throughout the length of the blade.

Abstract: A rotor apparatus comprising a blade having a root adapted to swing laterally within a supporting spindle under impact loading is provided with a flow path defining platform. The platform comprises an inner shroud extending generally laterally of the blade airfoil portion and adapted to swing laterally therewith. In one embodiment wherein the blade primarily comprises a laminate of composite filament plies, the inner shroud is bonded to the laminate. An outer shroud, fixed with respect to the supporting spindle, forms a lateral extension of the inner shroud with the blade in its normal operating position. The inner and outer shrouds are provided with a pair of complementary adjacent surfaces contoured to pass in relatively close-fitting relationship to each other when the blade swings under impact loadings.

Abstract: The composite filament laminates of a composite blade are splayed at the root thereof to receive metallic inserts therebetween. A transition material having a modulus of elasticity greater than that of the inserts and less than that of the laminates is bonded therebetween to more uniformly distribute the blade loadings into the root region.

Abstract: A turbomachinery rotor comprising a rotatable hub and a composite blade attached to the periphery thereof. The blade comprises a plurality of bonded filament laminates extending between, and wrapped around, a pair of hollow, semicylindrical inserts at the blade root. The laminates are bonded to the inserts so as to form a cylindrical blade root profile for insertion into a complementary cylindrical groove in the periphery of the hub. A slotted pin is positioned within the inserts to prevent the root from collapsing under loadings and to retain the blade in the hub.

Abstract: A flexure for connecting the root end of a rotor end of a rotor blade to a rotor hub in a bearingless rotor assembly. The flexure inherently induces a change in pitch angle in accordance with a change in flap angle. The flexure, which may form an integral portion of the rotor blade, is constructed of a composite material made of fibers secured to one another by a bonding agent. The fibers are arranged in two sets. The variation of the blade pitch angle in accordance with the blade flap angle is accomplished by either varying the number of fibers between the two sets or varying the angle of each set to the longitudinal axis of the flexure, or both.

Abstract: A torsionally compliant helicopter rotor blade with maximum blade torsional flexibility at the blade tip portion and so shaped at the blade root portion that the locus of shear centers and the locus of centers of lift are substantially coincident, and so shaped at the tip portion so that the locus of shear centers is selectively forward of the locus of centers of lift to establish an aerodynamic restoring moment in response to blade tip torsional excursions, thereby improving blade torsional stability.

Abstract: A blade for use in a fluid flow machine such as a compressor or fan is fabricated by laying up and bonding together a plurality of filament laminates. The filaments of at least a portion of the laminates are skewed, in a chordwise direction, forward and aft of a non-radial blade axis, thus forming a biased layup with the blade center of twist biased forward or aft of the blade radial axis. This significantly increases the torsional frequency of the blade. In one embodiment, the filaments are skewed forward such that no filaments run from the blade leading edge to the blade tip but, rather, from the blade leading edge to the blade root. This orientation permits more strain produced by foreign object impact to be transmitted to the blade root where it can be more easily absorbed and dissipated by the blade supporting disc.

Abstract: A rotor for a rotating wing aircraft has a star-shaped hub each arm of which supports a blade. The yoke between each blade and arm is a two tine fork constituted by a continuation of the blade root.

Abstract: A fan comprises a flat disc sandwiched between two hub members, together with two or more blades, ech blade having a boss with a slit so that the boss straddles the peripheral portion of the disc and is gripped by the hub members. Fans can readily be assembled with any required number of blades and the blades can be set at any required angle by cutting the slits at the appropriate angle.

Abstract: A blade fabricated of a plurality of bonded filament laminates, at least one of the laminates characterized by a plurality of continuous, collimated filaments embedded in a different matrix at the blade tip than at the blade root. The matrices are characterized by different relative impact strengths.

Abstract: There is disclosed a propeller adapted for driving a vehicle, such as a boat. The propeller comprises a pair of pivotally mounted propeller blades which are adapted to assume an inactive position wherein the blades are substantially aligned with the direction of vehicle movement, and a working position wherein the blades are at an angle with respect to the direction of vehicle movement. A stop means on the propeller limits the forward pivotal movement of the propeller blades to those locations between the inactive position and a stop position wherein the propeller blades each forms an oblique angle with respect to the inactive position so the propeller blades can each assume a working position which is located on either side of a perpendicular position wherein the propeller blades are perpendicularly disposed to the direction of vehicle movement.

Abstract: An improved rotor for a helicopter comprises a yoke at the inner end of each arm engaging the rotor hub by way of a spherical abutment.

Abstract: Methods for forming a composite ring having unidirectional filaments embedded in a polymer matrix is disclosed. The filaments are spirally wound within the ring to form a plurality of essentially circular hoops which are in coaxial alignment with the expected lines of principle force. In one embodiment the formed ring is structurally integrated into the rotor of a gas turbine engine to reinforce the rotor and to restrain the rotor blades which extend outwardly of the ring.

Abstract: A radial flow fan of short axial length and large radial dimensions and of the type having the drive motor arranged coaxially with respect to the fan wheel and at least partly inside of the fan wheel. The housing for the fan wheel and motor includes a flat metallic square plate forming an axial end face and a synthetic resinous material circumferential housing attached to the metal plate. The circumferentially extending housing portion also includes a portion defining the opposite end wall of the casing with respect to the metal plate end wall, which opposite end wall has a central opening for inlet of air. The synthetic resinous housing portion includes an exit port for radial exit of the air. The metal plate is connected with good heat conductivity with the stator of the drive motor by way of a flange of a bearing for the shaft of the drive motor and by way of a contact disc which axially supports the rotor shaft at the metal plate.

Abstract: An automotive engine cooling fan assembly including asymmetrical plastic fan blades and a torsion bar interconnecting each blade to the hub of the assembly, the asymmetrical blades responding to both aerodynamic and centrifugal forces to reduce the pitch thereof at high fan speeds, the entire fan blade subassembly being rotated as a result of the twisting of the torsion bar.

Abstract: A composite flywheel assembly for an air-cooled internal combustion engine including a cast iron flywheel which provides the inertial drive for the engine and a separate blower member having a circumferential array of vanes for propelling a flow of cooling air past cooling fins of the engine. The blower member is a one-piece molded impeller of flexible plastic material and is releasably retained on the inertia wheel by a snap-on interlocking engagement about the outer periphery of the flywheel. The closed end of a starter cup is received over an engine crankshaft and engages a conical skirt extending inwardly from the impeller base to spring bias the impeller against the flywheel.

Abstract: A plastics rotor blade, particularly for a helicopter, is formed with elongate filaments or rovings forming a loop for securing to a hub pin. The loop contains a metal socket secured to an extension extending between the loop walls.

Abstract: An air impeller of molded plastic construction includes a plurality of similar circumaxially arranged air moving blades and a central hub section. At the hub section, a plurality of similar axially projecting flexible fingers are formed integrally and arranged in a circumaxially spaced series to form a collet which defines a cylindrical hub cavity. A metal hub of cylindrical form and apertured centrally is disposed in the cavity and has a set screw for positive connection with a drive shaft entered in its central aperture. An arcuate clamping ring disposed about the fingers urges the fingers radially inwardly into engagement with the hub and thus retains the hub in the cavity. Radially aligned gaps in the fingers and the clamping ring receive an outer end portion of the set screw to lock the hub and clamping ring against rotation relative to the fingers. Lips may be provided at outer end portions of the fingers and a radial wall at an opposite end of the hub cavity cooperates to secure the hub axially.

Abstract: An improved blower blade for electric motors is disclosed. The blower blade comprises from about 50 to about 75% polypropylene, from about 5 to about 10% glass fibers and from about 15 to about 45% inert filler.