Laminated core manufacturing method

A laminated core manufacturing method for producing a stator core including a predetermined number of split stator pieces, each of the split stator pieces including a split yoke piece and a tooth piece, a plurality of the split yoke pieces defining an annular yoke piece when connected in a circumferential direction of a center axis, the tooth piece being made of a material that is same as a material of the split yoke piece and being formed continuously from the split yoke piece and extending radially inward of the yoke piece, the predetermined number of the split stator pieces are connected endlessly in the circumferential direction and are laminated in an axial direction, the method comprising:

• punching a center hole including the center axis from a center portion of a processing region provided in a workpiece, the processing region including a yoke piece formation region in which the yoke piece is formed and a tooth piece formation region in which the tooth piece is formed;
• extruding the yoke piece formation region and the tooth piece formation region in a thickness direction of the workpiece in a shape that is same as a shape of the split stator piece, and molding split stator piece portions adjacently in the circumferential direction around the center axis;
• pushing back and molding the split stator piece portions extruded;
• punching a contour of a portion that is molded in the workpiece and becomes the stator piece;
• and
• laminating, in the axial direction, and connecting the split yoke pieces and the tooth pieces;
• wherein
• in the molding the split stator piece portions, the split stator piece portions are extruded in parallel with the workpiece.