Abstract: A wind turbine control system for twin turbines mounted in common on an accelerator comprising a DC boost converter having pulse width capability, power, speed, current and voltage sensors responsive to an generator driven by one turbine, and a controller. The controller adjusts the PWM duty cycle to adjust generator output whereby to control turbine thrust and thereby adhere to a desired performance curve, and also changes thrust to adjust angular position of the accelerator and thus maintain optimum angle of attack of the wind on turbine blades.

Abstract: A method and apparatus for assembling permanent magnet segments and a back ring wherein a fixture holds segments in circumaxially spaced relationship, adhesive is applied to the segments, externally from pressure sensitive adhesive tape and the fixture then expands to urge the segments into firm bonding engagement with the back ring.

Abstract: A method of forming a composite panel with a facade comprising a planar arrangement of thin discrete facers on a body of structural backing material. The method comprises the steps of providing a horizontal casting bed, providing a plurality of facers each with chamfers at corners between side-rear and end-rear walls, arranging the facers in abutting relationship atop the casting bed and in a selected pattern in a face down planar configuration so that the chamfers on the facers open upwardly and define narrow elongated sealant channels at joints between contiguous facers. Depositing a sealant in the channels and pouring concrete as a structural backing material atop the facers, the rear surfaces of the facers and the concrete adhering to form a composite panel.

Abstract: A light-weight electric motor driven fluid pump assembly having a molded thermoplastic housing of two parts which form a fluid impervious rotor chamber, a stationary shaft journalled in the housing parts within the chamber and carrying a magnetic rotor and a fluid impeller driven thereby. The housing parts also define inlet and discharge ports in communication with the rotor chamber adjacent the impeller blades. One portion of the housing of one housing part defines a cylindrical thin walled tubular configuration with a cylindrical exterior surface for mounting a stator thereabout. The housing parts are welded together at mating surfaces with the result that neither static nor dynamic seals are required in the assembly.

Abstract: An axial flow fan comprises a hub rotatable on a central axis and a plurality of radial blades extending from the hub, each having a root portion adjacent the hub and each having tip portion space radially from the hub and surrounded by an annular band. The root portions are substantially equally spaced circumferentially at their junctions with the hub and at least some of the tip potions are substantially unevenly space circumferentially. The latter is due to the condition that blade centerlines are pivoted through unequal angles about points along the junctions between the hub and the blade root portions.

Abstract: A vertical stack—vertical draft fireplace grate which has a forwardly inclined log retaining portion with a lowermost log in close proximity to the floor of the fireplace and which cooperates with the rear wall of the fireplace to hold logs in a V-shaped stack immediately adjacent the wall. Undesired smoke is eliminated, starting facilitated and heat radiation forwardly through the fireplace opening greatly enhanced, while both safety and automatic feeding features are also enhanced.