Abstract: A P.M. d.c. motor in which the permanent magnets thereof are provided as arcuate segments of predetermined length which rotate about a circular locus of core component defining pole assemblies. The paired permanent magnets are magnetized in a radial polar sense and interact in radial fashion with three core components of each pole assembly which include a centrally disposed core component extending within a channel between the magnet pairs and to adjacent inwardly and outwardly disposed core components also interacting with the permanent magnet radially disposed surfaces. With the arrangement, localized rotor balancing is achieved and, additionally, discrete or localized magnetic circuits are developed with respect to the association of each permanent magnet pair with a pole assembly.

Abstract: A p.m. d.c. motor in which a stator is structured as a magnetically permeable base upon which stator pole components are mounted in upstanding fashion. Each of the stator pole components is formed as a laminar core of elongate rectangular shape about which a plastic bobbin is slideably positioned. The field windings of the stator are wound about this bobbin to provide a structure having no flared tips or the like and wherein winding can take place on bobbins separately from the stator structure. A disk-shaped rotor carrying a sequence of flat permanent magnets is positioned over the tips of the stator components and is rotatably driven by select energization of the latter. Select skewing of the stator poles and design of the geometry of the permanent magnets functions to significantly reduce detent torque phenomena.