Hybrid step motor with greater number of stator teeth than rotor teeth to deliver more torque

Abstract

A step motor comprises both a rotor and a stator winding assembly. The rotor has a plurality Nr of rotor teeth. The rotor fits within the stator winding assembly and is seated by bearings on an axial shaft to rotate within the stator winding assembly. The stator winding assembly includes a stator with a plurality of stator poles and is wound with coils that can be driven in a series of phases to magnetically interact with the rotor. Each stator pole has a plurality of stator teeth. The total number Ns of stator teeth on all poles of the stator is equal to or greater than the number of rotor teeth (Ns≥Nr) to deliver more torque. Various embodiments of two-phase, three-phase and five-phase bipolar step motors having 8, 9 and 10 stator poles, respectively, and different numbers of teeth are provided, including two embodiments with nonuniform stators.

Dependencies are inferred from the claim text.