Patent ID: 6169349
Filing Date: 2001-01-02
Classification: H02K

Abstract:
A pancake type d-c motor comprising: a motor drive shaft, two or more rotor assemblies secured along the motor drive shaft each of the two or more rotor assemblies comprising at least two pairs of rotor legs being uniformly spaced about and extending radially outwardly from said motor drive shaft, a number of stator poles surrounding of said two or more rotor assemblies, the number being at least twice the total number of rotor legs of each of said two or more rotor assemblies, the stator poles being uniformly spaced about each of said rotor assemblies, with all of said stator poles associated with a given rotor assembly being of the same polarization, wherein an angular spacing between each of the rotor legs of each of said two or more pairs of rotor legs being equal to or less than an angular spacing between adjacent stator poles, said rotor legs having associated excitation windings which, when energized, cause the two legs of each pair of rotor legs to be oppositely polarized whereby outward ends of said rotor legs are rendered alternately south and north poles about the periphery of said rotor assembly, said rotor assemblies and their associated stator poles being uniformly spaced along said motor drive shaft, their rotor and stator poles being aligned with the corresponding rotor and stator poles of adjacent of said rotor and stator assemblies, and said corresponding rotor and stator poles of said adjacent rotor and stator assemblies being oppositely polarized as north and south poles, a rotor position sensor reporting instant rotor positions to a sequencing and control system, the sequencing and control system responding to identified rotor positions, selectively energizing and de-energizing said excitation windings of said stator poles as appropriate for sustaining the operation of said motor.