Patent ID: 8839503

Claim:
A method for manufacturing a stator assembly for an electric water pump, wherein the stator assembly generates a magnetic field according to a control signal and a rotor is rotated by the magnetic field generated at the stator assembly to pressurize coolant, the method for manufacturing the stator assembly comprising: a) stacking a plurality of pieces made of a magnetic material to form a core stack; b) molding an insulator to the core stack; c) coiling a coil to the insulator to form a single core-insulator assembly so as to form a magnetic path; and d) connecting a plurality of single core-insulator assemblies in an annular shape in sequence in a circumferential direction to form the stator assembly; wherein a mounting groove and a mounting protrusion are formed to the insulator with the step b) or between the steps of b) and c); wherein the insulator includes an interior circumferential portion, wherein one lateral side of the interior circumferential portion of the insulator is provided with the mounting groove along a full length of the lateral side in an axial direction of the stator assembly, and wherein the other lateral side of the interior circumferential portion of the insulator is provided with the mounting protrusion along a full length of the other lateral side thereof in the axial direction of the stator assembly; and wherein the plurality of single core-insulator assemblies are connected with each other by inserting, in the axial direction of the stator assembly, the mounting protrusion of one single core-insulator assembly in into the mounting groove of an adjacent single core-insulator assembly.