Patent ID: 6568066
Filing Date: 2003-05-27
Classification: H02K,Y10T

Abstract:
A method for manufacturing a miniature motor comprising a plurality of magnets serving as stator poles and attached to an inner surface of a motor casing having a closed-bottomed cylindrical shape, a salient-pole rotor having a core mounted on a rotor shah and windings placed on the core; and a commutator mounted on the rotor shaft, said method comprising the steps of:blanking core laminations from sheet steel, each of the core laminations including a center portion having a hole formed therein at a center for engagement with the rotor shall, a plurality of leg portions extending integrally and radially from the center portion in equal number with the salient poles, and a plurality of wing portions, each extending integrally and symmetrically from an end of each of the leg portions, a radius of a circumcircle of each of the wing portions which is curved slightly being greater than a designed final radius of curvature of outer circumferential surfaces of the salient poles of the rotor; superposing the core laminations on each other to thereby obtain a laminated core; mounting the laminated core and the commutator on the rotor shall; placing windings on the laminated core; and pressing the laminated core with windings from a radially outward direction to change the radius to the designed final radius of curvature of outer circumferential surfaces of the salient poles of the rotor by use of a forming jig having a pressing surface of a radius of curvature substantially equal to the designed final radius of curvature of outer circumferential surfaces of the salient poles of the rotor.