Insertion of pre-fabricated concentrated windings into stator slots

1. A method of manufacturing a motor stator including:

a stator core provided, in an inner surface thereof, with a plurality of slots and a plurality of teeth each radially inwardly extending and tapering toward the center of the stator core, the teeth including at least a first tooth, a second tooth, and a third tooth, and the slots and the teeth being arranged alternately; and

a plurality of trapezoidal coils having the same shape, each of which is inserted in each slot, each coil being formed of a rectangular conductor that has a rectangular cross-section and is concentrated-wound into a trapezoidal shape,

wherein the method comprises:

individually mounting the coils on the second and third teeth located on both sides of the first tooth;

elastically deforming one of the coils having an air core before it is mounted on the first tooth, and inserting a first part of the elastically deformed coil into the slot on one side of the first tooth; and

inserting a second part of the elastically deformed coil into the slot on the other side of the first tooth while returning to an original shape by its elasticity resulting from elastic deformation.

2. The method of manufacturing the motor stator according to claim 1 further comprising:

mounting one of the coils on an initial one of the teeth;

inserting another coil in the slots on both sides of a next tooth by sliding the coil along one side surface of the next tooth; and

sequentially inserting the coils in the remaining slots but a last one.

3. The method of manufacturing the motor stator according to claim 1 further comprising:

elastically deforming the flat rectangular conductor of the trapezoidal coil obliquely to provide a narrower width of the rectangular conductor in a direction of inserting the coil into the slot.