Tap changing autotransformer

Claim 1

IN AN AUTOTRANSFORMER HAVING HIGH VOLTAGE TERMINAL, A GROUNDED TERMINAL ALTERNATIVELY CONNECTED TO A NEUTRAL POINT AND A MEDIUM VOLTAGE TERMINAL, TWO ALIKE SYMMETRICALLY DISPOSED WINDING HALVES ELECTRICALLY CONNECTED IN PARALLEL BETWEEN SAID HIGH VOLTAGE TERMINAL AND SAID GROUNDED TERMINAL FORMING THE WINDING OF THE AUTOTRANSFORMER, SAID WINDING HAVING TWO LIKE SYMMETRICALLY DISPOSED TAPPED WINDING SECTIONS EACH IN A RESPECTIVE WINDING HALF, EACH HAVING RESPECTIVE TAPS SO ANY ONE OF SEVERAL VOLTAGES MAY BE SELECTED THEREFROM AND THE TAPS OF THE TWO SAID TAPPED WINDING SECTIONS BEING CONNECTED IN PARALLEL, FOR EACH WINDING HALF TWO WINDING SECTIONS DISPOSED ON EACH SIDE OF THE TAPPED SECTION AND CONNECTED IN SERIES THEREWITH, TWO CORRESPONDING SECTIONS OF THE HALVES BEING CONNECTED TO THE HIGH VOLTAGE TERMINAL AND THE TWO OTHER CORRESPONDING SECTIONS BEING CONNECTED TO THE GROUNDED TERMINAL, FOR EACH WINDING HALF AND A PAIR OF ELECTROSTATIC SHIELDS ELECTRICALLY CONNECTED TO THE MEDIUM VOLTAGE TERMINAL AND SANDWICHING THE TAPPED WINDING SECTION IN THEIR RESPECTIVE WINDING HALF, AN ELECTROSTATIC SHIELD ELECTRICALLY CONNECTED TO THE HIGH VOLTAGE TERMINAL AND DISPOSED BETWEEN THE TWO CORRESPONDING WINDING SECTIONS CONNECTED TO SAID HIGH VOLTAGE TERMINAL, EACH OF SAID TAPPED WINDING SECTIONS COMPRISING A PAIR OF FLAT COILS IN SERIES, SAID WINDING SECTIONS DISPOSED IN EACH HALF ON EACH SIDE OF THE TAPPED SECTION COMPRISING FLAT COILS IN SERIES MADE OF SPIRALLY WOUND CONDUCTORS, THE DIAMETERS OF THE DIFFERENT COILS INCREASING PROGRESSIVELY AS THEIR POTENTIAL DECREASES, AND SWITCHING MEANS ELECTRICALLY CONNECTED TO SAID MEDIUM VOLTAGE TERMINAL AND SELECTIVELY OPERABLE TO DIFFERENT POSITIONS FOR ELECTRICALLY CONNECTING INDIVIDUAL ONES OF THE TAPS TO THE MEDIUM VOLTAGE TERMINAL.