Patent ID: 7841832
Filing Date: 2010-11-30
Classification: F04D

Abstract:
1. A fan comprising: a substantially cylindrical rotor holder with a lid rotatable about an axis; a substantially annular rotor magnet secured on the inner peripheral surface of the rotor holder; an armature arranged inside the rotor holder and facing the rotor magnet; a substantially cylindrical hub extending along the axis and having a circumferential wall secured to an outer surface of the rotor holder; and a plurality of blades arranged on the hub and turnable by the torque to generate an airflow, wherein a weight adjusting portion is provided at one of axial ends of the hub to project inward in a radial direction substantially perpendicular to the axis, the weight adjusting portion and the hub covering at least an outer periphery of the lid of the rotor holder, and the weight adjusting portion is axially spaced away from the rotor holder.