Vertical windmill with omnidirectional diffusion

A windmill for producing power in a moving body of air comprising:

• a support frame having an upper support bar and vertical steel tubes;
• a central shaft rotatably mounted to said support frame along a vertical axis of the support frame;
• a plurality of elongate airfoils rotatably mounted on the ends of radial struts at a fixed radial distance from the central shaft;
• a plurality of vertical elongate stators mounted between said upper support bar and the ground radially outwardly from said airfoils, each stator being mounted on the vertical steel tubes equally spaced circumferentially around, and at a uniform radial distance from, the central shaft and each stator having an elongate cross-section with the major dimension of said elongate cross-section extending substantially radially from the central shaft to form an omnidirectional diffuser;
• each stator being attached to the steel tubes through bearing connections at a position offset from the centroid of the stators to allow the stators to rotate from radial alignment to variable alignment to increase efficiency and to withstand high winds;
• a weight movably attached to each stator at a point offset from the steel tube and the centroid by a cable passing through pulleys, said weight and cable forming a means for resisting rotational movement of the stator and a means for returning the stator to a predetermined radial alignment in predetermined respective wind conditions;
• a central disc that is mounted around the central shaft of the windmill;
• a plurality of cam-cable braking mechanisms, one connected to each airfoil and associated radial strut, for rotating the airfoils and reducing the lift on the airfoils, each cam-cable braking mechanism comprising:
• a flat cam plate lying in a horizontal plane and pivotably mounted on the radial strut with a rotational axis parallel to, but offset from, the axis of rotation of the airfoil;
• a vertical shaft attached to the cam plate;
• a rail attached to the bottom of the airfoil;
• a rail bearing rotatably mounted on the vertical shaft and removeably inserted within a slot in the rail;
• a first cable attached at one end to the cam plate offset from the rotational axis of the cam plate and at the other end to the central disc;
• and
• a second cable attached at one end to the cam plate offset from the rotational axis of the cam plate in a relative position opposite that of the first cable, and at the other end to a spring that is affixed to the radial strut radially inwardly of the cam plate, said spring acting to hold the cam plate and the airfoil in a position to provide maximum lift when tension in the first cable is relatively small;
• a disc brake positioned to exert pressure against the central disc and slow the relative rotational speed of the central disc with respect to the rotational speed of the central shaft, thereby increasing the tension in the first cables and rotating each of the cam plates and each of the airfoils to reduce the lift of each of the airfoils;
• a retaining spring attached between the central disc and a stop on one of the struts to hold the central disc in the null operational condition except when the central disc is acted on by an external force sufficient to overcome the tension in the spring and cause the central disc to rotate relative to the rotation of the central shaft;
• a stop/release mechanism comprising:
• a sleeve mounted on the central shaft;
• a plate mounted on the central shaft above the sleeve;
• a right angle bracket pivotally mounted to the sleeve;
• a gate shaft mounted by two pillow blocks to the bottom of the right angle bracket;
• a first stop mounted to the central disc at a predetermined angle with respect to the position of the gate shaft during rotation of the central shaft at a predetermined rotational speed range;
• a third cable attached to the right angle bracket and to a spring attached to the plate, said spring thereby creating a force that, if not overcome by centrifugal force exerted against the right angle bracket when the central shaft is rotating, pivots the right angle bracket radially toward the central shaft and lifts the gate shaft over the first stop when the central disc rotates relative to the central shaft and causes the first cables to pivot the cam plates and remove the rail bearings from the rails;
• a second stop mounted on the central disc that contacts an angle bracket mounted to the bottom of the sleeve as the rotation of the central shaft slows;
• means for applying the disc brake to slow rotation of the airfoils comprising:
• a series of joints connecting the disc brake to the radially inward end of a lever arm;
• a weighted block on the outward end of the lever arm;
• a line connected between the weighted block and a winch;
• and
• means for activating the winch to release the line and to lower the block and thereby to cause the disc brake to exert pressure against the central disc;
• a centrifugally actuated braking mechanism comprising:
• a weighted lever pivotally mounted to one of the radial struts;
• a spring connecting an inner portion of the strut to the weighted lever;
• a target on the end of a piece of angle iron;
• a notch in the angle iron that holds a stop that is fixed to a bar;
• a spring that pushes against a fixed housing and pulls the bar and a connecting tether;
• and
• a winch release attached to one end of the tether that activates the winch when the weighted lever, acting under the influence of centrifugal force caused by rotation of the central shaft, radially pivots through a predetermined angle toward the circumference of the windmill and strikes the target, pivoting the angle iron about a rod, causing the spring to pull the bar and the tether, and thereby lowering the weighted block and activating the disc brake;
• means for slowing the rotation of the central disc relative to the rotation of the central shaft, thereby activating the cam-cable braking mechanism to govern and maintain rotational speed of the windmill within a structurally safe range, comprising:
• a centrifugal arm pivotably attached to a first one of the radial struts at a hinge point and extending therefrom radially toward the central shaft;
• a spring attached at one end to a second one of the radial struts and at the other end to the centrifugal arm at a point proximate to the hinge point;
• and
• a fourth cable attached to the centrifugal arm and to the central disc, said fourth cable designed to cause the central disc to rotate relative to the central shaft when the centrifugal arm is pivoted about the hinge point in response to centrifugal force caused by a high rotational speed of the central shaft and tension is thereby created in the cable;
• means for transferring power from the central shaft comprising:
• a transmission drivingly connected to the central shaft;
• a main generator drivingly linked to the transmission by a first V-belt and mounted remote from the transmission in a first direction;
• a motor/generator drivingly linked to the transmission by a second V-belt and mounted remote from the transmission in a second direction;
• a retention spring to hold the transmission against a low torque stop;
• means for pivoting the transmission away from the low torque stop towards a high torque stop under the influence of a predetermined torque thereby loosening the first V-belt and tightening the second V-belt;
• and
• an electronic tachometer switch that activates the motor/generator and deactivates the main generator at a predetermined main generator speed and that deactivates the motor/generator and activates the main generator at a predetermined main generator speed.