Patent ID: 7919893

Claim:
A motor rotor comprising: a hub including a peripheral wall having an inner peripheral face; a metal ring including an engaging portion and an inner peripheral face, with the metal ring being formed by bending a strip of metal plate to form a cylindrical ring, with the metal plate including first and second positioning portions on two ends thereof, with the first and second positioning portions being coupled with each other to form the engaging portion, with the metal ring including a coupling section on an outer peripheral face thereof, with the coupling section extending from the first positioning portion to the second positioning portion, and with the coupling section being coupled to the inner peripheral face of the peripheral wall of the hub; and a magnet ring coupled to the inner peripheral face of the metal ring, wherein the coupling section includes a plurality of grooves, and the inner peripheral face of the peripheral wall of the hub includes a plurality of annular ribs coupled in the plurality of grooves.