Step motor

Claim 1

A STEP MOTOR HAVING A PLURALITY OF STEPS PER REVOLUTION COMPRISING A PAIR OF CONCENTRIC STATOR MEANS INCLUDING A PAIR OF COAXIAL ANNULAR STATOR COIL MEANS FOR DEFINING A MAIN COIL AND AN AUXILIARY COIL, SAID COIL MEANS BEING SEPARATED BY A FIRST PLATE OF FERROMAGNETIC MATERIAL HAVING A PLURALITY OF PAIRS OF MAIN STATOR POLES AND ALSO A PLURALITY OF PAIRS OF AUXILIARY STATOR POLES, THE PLURALITY OF PAIRS OF SAID MAIN STATOR POLES BEING EQUAL TO SAID PLURALITY OF STEPS, SAID STATOR POLES BEING ORTHOGONAL WITH SAID FIRST PLATE AND ANNULARLY ARRANGED IN CONCENTRIC SPACED RELATION ABOUT THE PERIPHERY OF SAID AUXILIARY COIL, A PAIR OF END PLATES IN SANDWICHED RELATION WITH SAID STATOR COILS, EACH SAID END PLATE HAVING A PLURALITY OF PAIRS OF STATOR POLES, SAID STATOR POLES OF EACH SAID END PLATE BEING ORTHOGONAL AND IN ANNULAR ARRANGEMENT THEREWITH, SAID PLURALITY OF STATOR POLES OF ONE SAID END PLATE SURROUNDING SAID MAIN STATOR COIL AND EXTENDING INTO NESTING RELATION BETWEEN SAID MAIN STATOR POLES OF SAID FIRST PLATE SURROUNDING SAID AUXILIARY STATOR COIL, SAID PLURALITY OF STATOR POLES OF THE OTHER SAID END PLATE CONCENTRICALLY SURROUNDING SAID AUXILIARY STATOR COIL AND BEING IN CONCENTRIC STAGGERED RELATION WITH THE AUXILIARY POLES OF SAID FIRST PLATE, SAID MAIN STATOR POLES AND SAID AUXILIARY STATOR POLES DEFINING AN ANNULAR GAP THEREBETWEEN, AN ANNULAR PERMANENT MAGNET ROTOR IN SAID ANNULAR GAP, SAID ROTOR HAVING INNER AND OUTER CIRCUMFERENCE SURFACES ADJACENT SAID STATOR POLES, EACH SAID CIRCUMFERENTIAL SURFACE HAVING A PLURALITY OF MAGNETIC POLES OF ALTERNATE OPPOSITE POLARITY EQUAL IN NUMBER TO SAID PLURALITY OF MAIN STATOR POLE PAIRS, MEANS FOR SHIFTING THE EXCITATION OF THE POLES OF SAID AUXILIARY STATOR 90 ELECTRICAL DEGREES IN A LEADING SENSE WITH RESPECT TO THE POLES OF SAID MAIN STATOR THEREBY TO DETERMINE THE DIRECTION OF ROTATION OF SAID ROTOR.