US Patent 7688171 Transformer and rectifier circuit using such transformer

A transformer includes a primary winding coil, a winding frame member, multiple first three-dimensional conductive pieces, a second three-dimensional conductive piece, a magnetic core assembly and a fixing plate. The winding frame member includes a first winding frame and a second winding frame for winding the primary winding coil thereon. The first three-dimensional conductive pieces are respectively sheathed around the first winding frame and the second winding frame of the winding frame member. The second three-dimensional conductive piece is arranged between the first three-dimensional conductive pieces. The magnetic core assembly is partially embedded into the first three-dimensional conductive pieces, the first winding frame, the second winding frame and the second three-dimensional conductive piece. The fixing plate is connected with the first three-dimensional conductive pieces and the second three-dimensional conductive piece so as to fix the first three-dimensional conductive pieces and the second three-dimensional conductive piece.