Abstract: An improved method for creating cooling ducts in cast resin coils uses uniform cross section thermoplastic tooling segments. These segments are wound into windings between predetermined layers or radial sections, oriented parallel to the coil axis. They extend through the height of the coil. After the coil is cast, impregnated, or saturated with resin, and the resin is cured, the segments are withdrawn. The removal of a segment results in a continuous cooling duct. The thermoplastic segments are either solid machined from sheet or extruded with thin outer walls. Extrusion allows for uniform cross section relatively long somewhat flexible segments, which will cause the radius of curvature of the segment to conform to the shape of the coil due to the tension from the conductor and reinforcing material during the winding process. This will have the result of reducing the number of different segment designs required to support production of a variety of different diameter coils.

Abstract: The present invention relates to a transformer comprising a coil having an insulated wire formed into a plurality of turns defining a layer and a resistive element wrapped around the outer surface of the layer. The resistive element couples one of the plurality of turns with another of the plurality of turns. The resistive element not only increases the series capacitance of the transformer, but also increases the series conductance of the transformer circuit. The increase in the series resistance increases the dampening of the switching resonance.

Abstract: Disclosed is a method for making a laminate having utility in an electrical inductive apparatus, which first comprises coating at least one side of a metal substrate with a solventless liquid resin system comprising an ultraviolet radiation curable acrylic or vinyl monomer and a heat reactive thermoset adhesive resin. The resin system on the coated metal substrate is then exposed to ultraviolet radiation to cure the ultraviolet radiation curable monomer. The resin system is now a tacky solid layer. The laminates so formed can be assembled into components for use in applications such as electric power transformers, ignition coils, generators, chokes, reactors, solenoids ballasts, motors and electronics, in which prior art laminates have been utilized. The assembled laminates are then exposed to sufficient heat to cure the heat reactive thermoset resin and adhere the laminate layers together.