Patent ID: 8407731

Claim:
A motor, comprising: a stationary unit comprising a stator; and a rotary unit comprising a rotor holder and a chucking device, wherein the rotor holder is made of a metal member, the rotor holder comprising: a circular plate portion having an upper surface; and a substantially cylindrical holder portion having a first outer surface extending downwards from a radial outer edge of the upper surface of the circular plate portion, the substantially cylindrical holder portion holding a magnet on an inner circumferential surface thereof, the stator radially opposed to the magnet, wherein the chucking device comprising: a turntable made of a resin having a substantially cylindrical outer peripheral wall extending downward, the substantially cylindrical outer peripheral wall having a second outer surface; and a plurality of balls arranged inside the substantially cylindrical outer peripheral wall to roll in a circumferential direction with respect to a center axis, wherein the turntable is secured to the circular plate portion, such that a lower end of the second outer surface is directly attached to the rotor holder, the lower end located below the upper surface.