ROTOR OF SMALL-SIZED MOTOR

摘要

A rotor (10) for a miniature electric motor includes a magnet (12) having a rotation axis (14) and a shaft (16) fixed concentrically to the magnet. The magnet (12) includes a through hole (20) extending coaxially with the rotation axis (14). The shaft (16) includes a portion (24) fitted in the through hole (20). The portion (24) has an axial interengagement length (t1) shorter than an axial length (T1) of the through hole (20). The rotor (10) also includes reinforcing means provided at least inside the through hole (20). The magnet (12) comprises an annular magnet material (18), and a coating (22) formed on a surface of the magnet material and arranged at least inside the through hole (20). The reinforcing means is formed as the coating (22) of the magnet (12), and acts to ensure a fixing force to securely hold the shaft (16) in a predetermined position on the magnet.