Patent ID: 8102090

Claim:
A brushless rotary motor comprising: a rotor having a rotor axis and first and second magnet assembly that include a plurality of permanent magnets that are held together such that same magnetic poles contact one another; and a stator including magnetic coils encircling the rotor, the rotor and the stator being changeable in position relative to one another; wherein each of the plurality of permanent magnets is a fan-shaped magnet that is magnetized in a circular direction on a plane vertical to the rotor axis, an upper part of the first magnet assembly and a lower part of the second magnet assembly are held by magnetic yokes such that the plurality of fan-shaped magnets of the first and second magnet assembly are in a circular disc shape while the same magnetic poles contact one another, the first and second magnet assembly generate a strongest magnetic field along a magnetic field direction lying in multiple radial directions along each homopolar contact plane at which the same magnetic poles contact one another, the magnetic coils are positioned so that current flows in a direction intersecting the magnetic field direction, and the magnetic coils include a plurality of A phase coils and a plurality of B phase coils, the plurality of A phase coils is located in the vicinity of and faces the first magnetic assembly, the plurality of B phase coils is located in the vicinity of and face the second magnet assembly, and the plurality of A phase coils and the plurality of B phase coils are sandwiched by the first and second magnet assembly in a rotor axis direction.