SINGLE-PHASE SYNCHRONOUS MOTOR Russian patent published in 2000 - IPC

FIELD: stepping motors. SUBSTANCE: motor has stator with annular coil placed between butt-end assemblies of magnetic core carrying claw-shaped poles and rotor with multipole magnet. Rotor magnet carries as many poles as stator core. The latter are combined in even number of groups incorporating equal number of poles, mainly two poles per butt-end assembly of core. All poles of non- adjacent pole groups are provided with pole shaders. Pole arc in each pole group equals 0.6-0.7 of pole pitch; poles of each group are spaced 180 el deg. apart and groups of shaded and non-shaded poles are relatively shifted through 90-110 el. deg. Poles of opposing butt-end assemblies overlapping in width are made shorter and have axial clearance between them. Spacing shaded and non-shaded poles 90-110 el. deg. apart enables correction of pull-in torque reactive component. EFFECT: reduced power requirement at high starting and running characteristics. 3 cl, 3 dwg