Resin molded stator and manufacturing method thereof

A method for manufacturing a resin molded stator, the method comprising:

• a) preparing a straight winding core comprising a plurality of core elements, a plurality of joints, and a plurality of windings,
• wherein the plurality of core elements are linearly arranged,
• the core elements each comprise a partial core back and a tooth,
• neighboring partial core backs of the partial core backs are coupled together by one of the joints, and
• the windings are wound around the respective teeth;
• b) bending the straight winding core at the plurality of joints into an annular shape in which the plurality of teeth are directed radially inward and
• causing distal ends of the plurality of teeth to face an outer peripheral surface of a columnar core metal to thereby obtain a core metal assembly in which a stator is mounted on the core metal, and
• arranging the core metal assembly in a mold, or
• causing distal ends of the plurality of teeth to face an outer peripheral surface of a columnar core metal in a mold provided with the core metal to thereby obtain a core metal assembly in which a stator is mounted on the core metal, and
• locating the core metal assembly in the mold;
• c) injecting a resin into the mold, covering at least the windings of the respective teeth with the resin, and curing the resin;
• and
• d) removing the stator molded with the resin from the mold and the core metal, wherein
• the core metal comprises a plurality of ribs that project radially outward from the outer peripheral surface, the number of the ribs being three or more and less than the number of the teeth,
• each of the plurality of ribs extends parallel to a center axis, and
• in the core metal assembly, each of the plurality of ribs is located in a gap between the distal ends of the teeth adjacent to each other.