Abstract: A laminated iron core includes a plurality of stacked iron core pieces punched out from a thin steel sheet material, each iron core piece including a plurality of slot holes for receiving coil windings. At least one electrically insulating sheet piece is stacked on an outer surface of a lowermost iron core piece. The electrically insulating sheet pieces include a spindle hole and a plurality of slot holes which have a substantially similar configuration to, but are smaller than, the slot holes of the iron core pieces whereby edges of slot holes of electrically insulating sheet pieces extend outwardly beyond edges of slot holes of iron core pieces. Burrs formed at edges of slot holes of iron core pieces are covered with edges of slot holes of electrically insulating sheet pieces so that a coil can be wound safely without directly contacting the burrs.