Micro stepping motor

A micro stepping motor for use in compact electronic timepieces and the like comprising:

• a magnetic core;
• a coil winding wound on said magnetic core;
• a stator having opposite end portions thereof connected to said magnetic core to define therewith a closed magnetic flux path, said stator having a region of reduced cross-sectional area along its length and having a hole extending through said stator at said region defining two stator magnetic poles one on either side of said hole along the stator length with the end faces of said stator magnetic poles defining stator pole faces;
• a rotor having at least a pair of magnetic poles and being rotatably disposed for rotation about a given axis in said hole with an air gap between said rotor and stator pole faces;
• and means defining two protrusions on respective ones of said stator magnetic poles at diametrically opposite sites around the circumference of said hole and coacting with said rotor for determining the rotor rest or stationary positions, said protrusions extending into and being coterminous with said hole and having a sufficiently small circumferential extent with respect to the remaining hole circumference so as to be ineffective as independent stator pole faces.