Patent ID: 7598644
Filing Date: 2009-10-06
Classification: F16C,H02K

Abstract:
1. A heat dissipating fan comprising: a housing defining an accommodating space and comprising a hollow tube, the tube enclosing first and second bearings therein, one of the first and second bearings being moveable along an axial direction of the tube; a stator arranged in the accommodating space and around the tube; a rotor having a shaft rotatably disposed in the first and the second bearing; and a buffer structure comprising a pair of magnets received in the hollow tube and located between the first and second bearings, the magnets each having two opposite magnet poles vertically arranged along the shaft, one of the magnets contacting with one of end surfaces of the one of the first and second bearings, the one of the magnets attached to the one of the first and second bearings to move with the one of the first and second bearings, the other one of the magnets being spaced from the first and second bearings and located between the other one of the first and second bearings and the one of the magnets, repellent force being generated between the magnets along the axial direction of the tube for cushioning an accidental force exerted on the one of the first and second bearings thereby preventing the one of the first and second bearings from moving towards the other one of the magnets.