Patent ID: 7234229

Claim:
A process for the preparation of a motor coil which is penetrated and retained by a column-shaped motor core and which has a ribbon conductor which is disposed such that a width direction of the ribbon conductor is extended in a radius direction of the motor core, the ribbon conductor being helically superposed on one another in an axis direction of the motor core and along an outer peripheral surface of the motor core, comprising: a first step for molding a mother material to prepare a first molded product comprising a column part, and a fin part projected in the form of flat plate from an outer peripheral surface of the column part to an outer side in a radial direction of the column part and helically continuing in an axis direction of the column part at predetermined intervals along the outer peripheral surface of column part; a second step for punching out the column part from the first molded product in an axis direction of the column part with retaining the fin part to remove the column part to prepare a second molded product helically formed by the fin part; a third step for coating the second molded product with an insulating film to prepare a third molded product; and a fourth step for pressurizing both sides of the third molded product in a direction having punched out the column part to deform the third molded product such that flat plate portions of the fin part are superposed on one another.