Motor provided with noncircular stator core, apparatus for production of motor, and method for production of motor

A motor comprising a stator core formed by stacking a plurality of noncircular core sheets, each of which is made from a rolled magnetic steel sheet, wherein

• the stator core includes:
• a first core sheet having a non-regular polygonal outside edge shape;
• and
• a second core sheet having an outside edge shape the same as the first core sheet, the second core sheet being stacked with respect to the first core sheet so that a rolling direction of the second core sheet becomes a direction rotated from a rolling direction of the first core sheet about a center axis of the stator core by an angle of an odd multiple of 360°/(number of poles of the motor×2), wherein
• the outside edge of the first core sheet is defined by:
• a first group of sides;
• and
• a second group of sides connected to the first group of sides, each of the second group of sides having a circumferential length less than the first group of sides, wherein
• the second group of sides includes a first and second sides at both ends in a direction perpendicular to the rolling direction of the first core sheet, the first and second sides being parallel to the rolling direction of the first core sheet, wherein
• the outside edge of the second core sheet is defined by:
• a third group of sides;
• and
• a fourth group of sides connected to the third group of sides, each of the fourth group of sides having a circumferential length less than the third group of sides, wherein the fourth group of sides includes a third and fourth sides at both ends in a direction perpendicular to the rolling direction of the second core sheet, the third and fourth sides being parallel to the rolling direction of the second core sheet, wherein
• a dimension in the direction perpendicular to the rolling direction of the first core sheet between the first side and the second side, and a dimension in the direction perpendicular to the rolling direction of the second core sheet between the third side and the fourth side are the same.