Abstract: A rotor blade actuation system is disclosed for controlling extension and retraction of an outboard blade section of a rotor blade by varying the speed and direction of rotation between a main rotor shaft and a blade actuation shaft. The rotor blade actuation system includes a drive gear on the main rotor shaft and a blade actuation drive gear on the blade actuation drive shaft. A primary drive unit is engaged with and transmits rotary motion from the main rotor shaft to the blade actuation shaft. The primary drive unit includes an input gear engaged with the drive gear. A primary drive is engaged with the drive gear through an input gear and a master clutch. An output drive is engaged with the blade actuation drive gear. A forward clutch controls engagement of a forward planetary gearset with the primary drive and the output drive. The engagement of the forward planetary gearset causes the blade actuation shaft to rotate in the same direction as the rotation of the main rotor shaft.

Abstract: A variable pitch propeller apparatus for use with a motor is disclosed. The apparatus includes a housing having a plurality of blades mounted therein for rotation. Adjustable high pitch and low pitch stop rings are connected to the housing and a synchronizer ring is slidably received by the housing and positioned between the stop rings. The synchronizer ring is limited in movement by the desired position of the adjustable high pitch stop ring and adjustable low pitch stop ring. A plurality of springs are used to bias the blades in a low pitch position for trolling and when the spring force is overcome by the thrust on the blades, the blades pivot to a high pitch position. The springs are cooperatively connected to the synchronizer ring or to the blades so that blade movement is coordinated and simultaneous. A tensioning ring is connected to the housing for simultaneously adjusting the tension on the springs.

Abstract: A Variable Diameter Rotor (VDR) system (4) having telescoping odd and even blade assemblies (O.sub.b, E.sub.b) wherein the odd blade assemblies define a radial length R.sub.O and the even blade assemblies define a radial length R.sub.E. Each blade assembly (O.sub.b, E.sub.b) defines an internal chamber (64) for accepting a positioning means (70) operative to effect telescopic translation of the blade assemblies (O.sub.b, E.sub.b) such that the radial length R.sub.E of the even blade assemblies (E.sub.b) is equal to the radial length R.sub.O of the odd blade assemblies (O.sub.b) in a first operating mode, and such that the radial length R.sub.E is between about 70% to about 95% of the length R.sub.O in a second operating mode. The positioning means (70) includes a centrifugal restraint assembly (80) disposed within each internal chamber (64) of the rotor blade assemblies (O.sub.b, E.sub.

Abstract: A mounting arrangement (100) for a Variable Diameter Rotor blade assembly (16) having an outer blade segment telescopically mounting to a torque tube member (24), and connecting means (70) for transferring centrifugal loads of the outer blade segment (22) to a rotor hub assembly (18). The outer blade segment (22) includes a spar member (30) having a longitudinal axis (26) and defining an internal channel (62) for accepting the torque tube member (24) and the connecting means (70). The mounting arrangement (100) couples the connecting means (70) to the spar member (30) and includes a restraint surface (86) formed within the spar member (30) and a restraint assembly (68) disposed in combination therewith. The restraint surface (86) is disposed inboard of the tip end (90) of the spar member (30) and in a plane oriented transversely of the longitudinal axis (26).

Abstract: A torque tube/spar assembly (100) for transferring operational loads of a Variable Diameter Rotor blade assembly (16) to a rotor hub assembly (18) and includes a torque tube member (24), a spar member (30) and a bearing assembly (40a, 40b) for telescopically mounting the spar member (30) to the torque tube member (24) and furthermore defines an internal channel (62) for housing a retraction/extension mechanism (64) which mounts to an internally formed restraint surface (86) of the spar member (30) and is operative to vary the length of the rotor blade assembly (18). The torque tube member (30) has a substantially constant external geometry along the length of bearing assembly engagement and defines a root end region (102), a tip end region (106) and an intermediate transition region (104) disposed therebetween.

Abstract: A device for converting wind flow energy into mechanical energy has a base construction and a rotor with an essentially horizontal axis mounted on the base construction. The rotor has a number of elongated rotor blades which are connected to a rotary support and extend essentially radially therefrom. Each rotor blade or a part thereof is connected to the rotor support by a hinge connection for tilting the longitudinal axis of the rotor blade or part thereof to a predetermined orientation relative to the axis of rotation of the support. A hinge axis of the hinge connection between the rotor blade and the rotary support is directed at an acute angle both to the longitudinal axis of the rotor blade and to the axis of rotation of the support.

Abstract: A rotor system (4) having odd and even blade assemblies (O.sub.b, E.sub.b) mounting to and rotating with a rotor hub assembly (6) wherein the odd blade assemblies (O.sub.b) define a radial length R.sub.O, and the even blade assemblies (E.sub.b) define a radial length R.sub.E and wherein the radial length R.sub.E is between about 70% to about 95% of the radial length R.sub.O. Other embodiments of the invention are directed to a Variable Diameter Rotor system (4) which may be configured for operating in various operating modes for optimizing aerodynamic and acoustic performance. The Variable Diameter Rotor system (4) includes odd and even blade assemblies (O.sub.b, E.sub.b) having inboard and outboard blade sections (10, 12) wherein the outboard blade sections (12) telescopically mount to the inboard blade sections (10). The outboard blade sections (12) are positioned with respect to the inboard blade sections (10 such that the radial length R.sub.E of the even blade assemblies (E.sub.

Abstract: A Variable Diameter Rotor (VDR) system (4) having telescoping odd and even blade assemblies (O.sub.b, E.sub.b) wherein the odd blade assemblies define a radial length R.sub.O and the even blade assemblies define a radial length R.sub.E. Each blade assembly (O.sub.b, E.sub.b) defines an internal chamber (64) for accepting a positioning mechanism (70) operative to effect telescopic translation of the blade assemblies (O.sub.b, E.sub.b) such that the radial length R.sub.E of the even blade assemblies (E.sub.b) is equal to the radial length R.sub.O of the odd blade assemblies (O.sub.b) in a first operating mode, and such that the radial length R.sub.E is between about 70% to about 95% of the length R.sub.O in a second operating mode.

Abstract: A variable pitch propeller assembly is disclosed for a power boat. Three blades are mounted on a housing carried by the propeller shaft. Each blade has an axle received in the housing. Each axle has a slot receiving a dowel carried in the housing so the blade can rotate about 5.degree. between two pitch positions. A centrifugally-operated, spring biased latch carried in the housing locks the shaft in each pitch position. The blade is released from the latch by a predetermined change in the hydrodynamic force acting on the blade surface. The propeller shaft is connected to the propeller assembly by three plastic keys which shear to permit the propeller assembly to spin with respect to the propeller shaft when the propeller assembly strikes a predetermined resistance, such as a rock or the like.

Abstract: A sleeve 18 spline-fitted in an outer periphery of a propeller shaft 4 is connected to a propeller boss 12 for surrounding the outer periphery of the sleeve by a damper rubber 20 interposed in superposed relation therebetween, and in a recess formed in the outer periphery of the propeller boss 12 so that a bottom surface thereof comes near the outer periphery of the damper rubber 20, propeller blades are rotatably supported on a blade shaft 33 parallel to the propeller shaft 4. With this arrangement, it is possible to provide a compact variable propeller for a boat which can be mounted on a relatively short propeller shaft and which is provided with a torque limiting device.

Abstract: There is provided a self-actuating variable pitch marine propeller which incorporates two or more blades, each independently rotatable, relative to the propeller hub, between a first lower and a second higher pitch. The blades are preferably mechanically linked by coordinating devices and are caused to move preferably by a combination of centrifugal force effect resulting from inertial masses means and the hydrodynamic forces acting upon the blade hydrodynamic surface. The rotation of the blades relative to the propeller hub is restrained until the restraint is overcome by the forces acting to pivot the blades to the higher pitch position. Most preferably there is also provided a mechanical bias, such as a spring to hold the blades in the lower pitch position. Initially, the hydrodynamic force can also tend to hold in the blades in the lower pitch position, or to move the blades towards the higher pitch.

Abstract: A drive system for varying the diameter of a variable diameter rotor has a gear drive system associated with a single coaxial shaft lower end which includes a gear set for increasing or decreasing the speed of rotation of the coaxial shaft relative to the rotor drive shaft to change the length of two or more variable length blades. Utilizing a single shaft system allows a variable diameter rotor drive system to be adapted to gimballed rotors which require shaft flexibility. Since only a single shaft extends through the rotor drive shaft, hub complexity is reduced.

Abstract: An automatic centrifugal force variable pitch propeller assembly includes a plurality of propeller blades mounted within a housing, each of the propeller blades being mounted to permit limited radial travel in its entirety and simultaneous incremental rotation about its longitudinal axis, the limited radial travel of each of the propeller blades in its entirety being caused by a centrifugal force developed by rotation of the propeller assembly and extending between an inward position corresponding to rotation of the propeller assembly at an idle speed and outward position corresponding to rotation at a maximum speed.

Abstract: A variable diameter rotor for a tilt rotor aircraft has an inboard section having a linear twist from a root end to an outboard end thereof, and an outboard section telescoped over the inboard section which additionally has a linear twist from a root end to an outboard end thereof. The outboard section is disposed at an offset of about 4.degree. to 15.degree. relative to the inboard section to provide a step wise change in twist angle when in the extended condition, such that the rotor when operated in the helicopter mode, can be operated at high blade pitch angles without premature stalling along the inboard airfoil surfaces This allows efficient operation at high thrust coefficient/solidarity ratios. Optionally, the trailing edge of the outboard section is rotated along the aft 30% of chord of the airfoil section to provide an equivalent twist increase in the offset at the transition between the blade sections.

Abstract: There is provided a self-actuating variable pitch marine propeller which incorporates two or more blades, each independently rotatable, relative to the propeller hub, between a first lower and a second higher pitch. The blades are preferably mechanically linked by coordinating means and are caused to move preferably by a combination of centrifugal force effect resulting from inertial mass means and the hydrodynamic forces acting upon the blade hydrodynamic surface. The rotation of the blades relative to the propeller hub is limited primarily as to speed of rotation by restricted viscous fluid flow damping means operably connected to the blades. In one preferred embodiment, the viscous flow means further acts as an initial restraint against all motion by closing off the viscous flow orifice until a certain minimum propeller rotational speed is achieved.

Abstract: An automatic variable pitch propeller including a central hub defining an axis of propeller rotation and a plurality of blades connected to and extending from the central hub substantially normal to the axis of rotation, each blade being mounted for rotation about a pitch axis, a cam mechanism to translate centrifugal forces imposed on that blade into a force tending to rotate that blade toward a course pitch, that force being opposed by water pressure tending to decrease blade pitch. The cam mechanism including a cam groove formed in an insert, of a material harder than the blades, in each blade shaft and the propeller being provided with variable minimum and maximum blade pitch stops, resilient bias toward minimum blade pitch and manual a pitch-up shift mechanism.

Abstract: A mechanism for varying the cycle of a power plant comprising a turbine ene having a housing connected to the rotating spool of the turbine engine with a plurality of propeller blades slideably attached to the housing such that at maximum rotational speed of the turbine engine the blades are extended beyond the cowling of the engine providing external airflow. A nonlinear spring is used for causing the propeller blades to stow within the confines of the cowling of the engine at minimum rotational speed of the engine thus providing no external airflow.

Abstract: Pitch of a blade (12) on an aircraft engine propulsor (14) is determined by employing a shaft (22) and a bevel gear (23) to alter relative circumferential distance between a first set of teeth (25) and a second set of teeth (26). Said teeth (25,26) creates fluctuations in a magnetic field generated by a magnetic poll piece (28a) wherein said fluctuations are converted to a signal (30) by a coil (28) located on a subsequent engine section (8). The time between pulses of the signal (30) is a function of said relative circumferential distance whereby the time between pulses is a function of the pitch of the blade (12).

Abstract: The invention concerns a system for reducing the resisting torque which must be overcome in changing pitch of aircraft propeller blades. The resisting torque includes gas twisting moment and centrifugal twisting moment. The invention includes a bearing system which derives a torque from radial motion of the blade, the radial motion being induced by centrifugal force. The derived torque opposes the resisting torque. The derived torque can also be used to not only oppose, but also overcome, the resisting torques. Such overcoming can be desirable because the resisting torques can drive the propeller blades into a flat pitch position if the pitch change mechanism fails.

Abstract: A blade attachment between a propfan blade and a propfan hub in a propfan propulsion system for a tube-launched expendable aircraft, the attachment including a hinger on a rotatable propfan hub on the aircraft, a stem of the propfan blade rotatably supported on the hinge, a pitch control arm rigidly attached to the propfan blade, and a pitch control link universally articulated at opposite ends to the pitch control arm and to the propfan hub. When the hinge is extended, the pitch control arm and pitch control link locate the propfan blade in a folded position generally flat against the fuselage of the aircraft for storage in and launch from a tube. After launch, the hinge rotates to a retracted position and the pitch control arm and pitch control link concurrently rotate the propfan blade to an unfolded position for propelling the aircraft forward when the propfan hub rotates.

Abstract: A multi-blade, variable pitch wind driven propeller in which a shock absorber is connected with each blade to dampen movement in both the radially inward and radially outward movements of the blade. Tension springs are connected with the blades to move them inwardly against centrifugal force, and in a preferred form of the invention, the tension spring has a variable rate so that it exerts greater resistance near its limit of outward travel. A coil compression spring may also be connected with each blade to absorb loads at the inner limit of travel of the blade and to impart an initial impetus to outward movement of the blade. In addition, retrofit lock nut means is provided for attachment to the ball stud connected to the butt end of each blade to extend along substantially the entire length of the stud and achieve a ratio of ball stud diameter, in inches, to rotor radius, in feet, of least as much as 0.100, thereby minimizing the risk of failure of the stud.

Abstract: By mounting an axle (18,19) in a wind mill wing (1) having a wing tip (22) capable of swinging out by means of a mounting (2,7,8) which may be bolted to the wing and which can furthermore squeeze about the axle (18), it is possible to mount this mounting on new wings as well as old wings in case the mountings thereof have become loose.

Abstract: An adjustable diameter screw propeller includes a hub having a plurality of spindles, each mounted in the hub for rotation about an axis disposed radially of the hub axis and a mechanism for synchronously turning the spindles in a common direction. A plurality of propeller blades having a fixed pitch contour and a skew in the range of 60.degree. to 90.degree. are attached to respective ones of the spindles, such that as the spindles are turned, the blades rotate between a first disposition in which the diameter of the propeller is maximum and a second disposition in which the diameter of the propeller is reduced. In addition, the pitch of the propeller increases as the propeller diameter decreases to compensate for the loss of power that would otherwise occur as the propeller diameter is decreased.

Abstract: An automatic variable pitch propeller comprising a central hub defining an axis of propeller rotation and a plurality of blades connected to and extending from said central hub substantially normal to the axis of rotation, each blade being mounted for rotation about a pitch axis, means to translate outward movement of that blade resulting from centrifugal forces imposed on that blade by rotation of the propeller into a force tending to rotate that blade about its pitch axis toward a feathered pitch condition, the force being opposed by a feathering force acting at a center pressure of the blade offset from the pitch axis, caused by resistance to rotation of said propeller and tending to decrease blade pitch toward a feathered condition.

Abstract: A ceiling fan is provided and includes articulated fan blades such that when the fan is off the blades will hang vertically downwardly by force of gravity and when the fan is turned on the blades will rise radially to a horizontal pitched angled position due to the coaction of centrifugal force, and wind reaction force.

Abstract: A variable-pitch bladed rotor including a plurality of blades extending outwardly from a hub in which they are each mounted by a respective ball-screw device. Each device comprises inner and outer races each provided with at least one helical groove, a plurality of balls co-operable with the grooves, and a cylindrical cage disposed between the races which is suitably apertured for accommodation of the balls. The cage supports gearing so associated with the inner and outer races that on pitch-change movement of the respective blade the cage is positively driven, thereby to turn about the blade longitudinal axis.

Abstract: There is disclosed an axial flow fan having blades which may be rotated about their axes to permit their pitches to be adjusted and which may be moved in a radial direction to adjust the clearance between their tips and the fan ring in which they rotate.

Abstract: A wind turbine having the tips of the blades pivotable to a position in which they act as brakes to slow the turbine down. The pivoting is caused by relative axial movement of the tip and main blade portions which is caused by the action of a spring. The spring action is normally overcome by a hydraulic actuator 16. When the hydraulic pressure exceeds a threshold value corresponding to a desired limit rotational speed of the turbine a pressure switch 83 causes a pressure release valve 84 to dump the fluid pressure in the hydraulic actuator 16, thus allowing the spring to operate and cause the pivoting of the tip.

Abstract: A wind powered device on a support structure is provided with a drive shaft mounted for rotation about its axis on the support structure and is coupled to an electric generator connected to a utility power grid.A rotor is mounted on the support structure and is adapted to drive the shaft, hence the electric generator. The rotor has at least one rotor blade. The rotor is mounted to drive the shaft and also for limited relative rotational movement with respect to the drive shaft about the axis of the drive shaft as the wind velocity driving the rotor changes. The coupling between the shaft and rotor responds to increases and decreases in rotor torque so that as imbalances between shaft torque and rotor torque arise, the rotor tends to run ahead of or behind the shaft.

Abstract: An improved pump for lifting water from an underground source utilizes a wind motor for driving an oil-less air compressor eliminating oil contamination of ground water which is forced to the surface. The wind motor is movable to face the wind by means of a novel swivel assembly which also eliminates the formation and freezing of condensate within the airline from the compressor. The propeller blades of the wind motor and the tail section are formed from a pair of opposed convex air foil shaped surfaces which provide the propeller blades and the tail section with fast sensitivity to slight changes in wind direction and speed. A novel well tower for supporting the wind motor and compressor and for lifting the water from the underground source is an optional modification which requires no welding and eliminates the problem of condensate freezing in the airline going to the well.

Abstract: A windmill speed limiting device is provided to prevent the windmill blades from going too fast during conditions of heavy winds. In order to slow down the windmill blades, the tips of the blades are turned relative to the main blade portion at high speeds. After the tips are turned, the windmill blade must return to a safe speed before the tips are returned to their normal position. A hysteresis effect by which the tip portions are rotated to their normal angular position in alignment with the main blade portion is implemented by means of a cam track, a pivot point below the center of the blade and a central spring loaded drum to which each of the blades are connected.

Abstract: A propeller assembly is provided in which the propeller blades are adjustable both rotatably and longitudinally. Pitch angle of the propeller blades may be adjusted by rotating the blades in the hub of the assembly. The outer diameter of the propeller blades may be adjusted by sliding the shafts of the blades into the hub of the assembly to a desired position and locking the shafts thereat by means of set collars. The hub of this propeller assembly is split providing for disassembly and removal of the entire propeller assembly from the drive shaft without removing inboard or outboard shaft bearings or other components. The entire assembly is specially designed for simplified construction by the average amateur homebuilder or hobbyist using only a hack saw, drill press and grinder. No casting, welding or machining is necessary.

Abstract: A propeller type wind motor arrangement having a blade mounting hub, a plurality of air foil blades, and blade receiving means for mounting the blades to the hub for pivotal movement about a longitudinal axis of the blades is provided with a governor for retaining the blades at a first high torque, relatively low tip speed ratio forming angle during motor start-up and at rotational speeds below a minimum normal operational speed, and for abruptly shifting said blades to a second high efficiency, relatively high tip speed ratio forming angle when said operational value is reached.

Abstract: A rotor blade extended radially from a hub, characterized by an elongated spar and a plurality of axially aligned shells pivotally mounted on the spar, each having an aerodynamic center located in trailing relation with the spar and supported thereby for simultaneous axial and angular displacement as centrifugal forces are applied thereto, and a pitch controller including a plurality of pivotal pitch limiting arms transversely related to the spar, each being characterized by a cam surface defined along one edge thereof, engaging in supporting relation a cam follower of a truck pivotally connected to a shell and supported thereby for pivotal motion about an axis coincident with a radius of said spar, and a push-pull link interconnecting the arms for imparting simultaneous pivotal motion thereto, whereby the angular relationship of the arms to the spar is varied for varying the motion of the trucks along the arms for thus limiting the pitch of the segments about the spar.

Abstract: A deployable stowed rotor having a rotor hub to which a pair of telescoping otor blades are connected is foldable into a package suitable for stowage prior to use. When the rotor is deployed, for example, as a lifting device for an ejection seat, positive preconing of the blades is provided by a spreading link arrangement connected to a drogue chute. Further coning during rotor spin-up is synchronized by intermeshed gears provided at respective one ends of the blades attached to the hub by teeter link hinges. Rotor speed is automatically regulated by a governing spring formed in conjunction with a helical spline arrangement between each of the blades and the hub and which varies the pitch of the spinning blades according to rotational velocity.

Abstract: A locking control system and an overtravel safety top system are presented for a variable length rotor blade system. The lock system has linkage and pawl apparatus operated by a pilot actuated lock shaft to lock and unlock the blade adjustment system. A traveling nut on the lock shaft actuates the lock linkage, either directly or through the lock shaft to lock the blade adjustment system to prevent overretraction or overextension in the event of malfunction of the extension control system.

Abstract: A locking control system and an overtravel safety stop system are presented for a variable length rotor blade system. The lock system has a lock mechanism operated by a pilot actuated lock shaft to lock and unlock the blade adjustment system. A traveling nut locks the blade adjustment system to prevent overretraction or overextension.

Abstract: A multiblade, wind-driven, variable pitch propeller is used in a wind electric plant for the generation of electrical power from wind forces, and the propeller is rotatable in a plane at an angle to the tower axis, enabling larger propellers to be used without propeller-tower interference and also reducing the distance between the propeller and gear case. A snubber arrangement is provided on the propeller blade return springs to slow the governor action and prevent abrupt pitch changes and damaging flutter of the blades, and a self-centering, double-acting pivot washer is provided between the propeller blades and the return springs to ensure free pivoting and long life of the spring connecting bolts. Adjustable positive blade stop bolts are engaged directly between the hub and the propeller blades to limit return movement thereof.

Abstract: A windmill having a plurality of pairs of diametrically opposed vanes mounted for rotation about a horizontal axis in alignment with the wind. The pairs of vanes are supported in uniformly spaced relationship to each other axially of the axis of rotation and each successive pair is indexed circumferentialy in the direction of rotation relative to the prior pair. The vanes are automatically moved to a less efficient position as the speed of the wind increases to limit the maximum speed of the windmill.

Abstract: A helicopter rotor having retractable blades each having a three dimensional truss including flexible cables which connect a blade member with a pitch member directly secured to a rotor hub, the cables providing for retraction of the blade member to a storage position and permitting the blade member to be adjustably extended to operative positions. With the rotor rotating normally, the resultant centrifugal force acting on the blade and more particularly the blade member, retains the cables under sufficient tension to form an operationally rigid truss which transmits the rotational force of the rotor to the blade member and also adjusts the pitch of the blade member responsive to operation of the pitch member. Two pairs of cables are provided, inner ends of each pair being spaced apart and retained by the pitch member, opposite ends of each pair being secured, one to each of opposite ends of a rigid rod transverse to the blade member and extending outwardly in opposite directions from the blade member.

Abstract: A variable length blade in telescopic form adapted to be used with similar blades to form a variable diameter rotor or propeller wherein the outer blade portion, at the will of the pilot, is caused to telescope with respect to the inner blade portion by jackscrew action and means are provided for limiting the extending and retracting movements of the blades and also for providing a continuing visual indication of the diameter of the rotor.