COOLING FAN WITH DAMPING STRUCTURE SUPPORTING A SHAFT OF THE COOLING FAN

摘要

A cooling fan includes a fan frame ( 10 ) having a central tube ( 12 ) defining a central hole (120) therein, a bearing ( 30 ) received in the central hole and a rotor ( 20 ) being rotatable with respect to the stator. The rotor includes a rotary shaft ( 24 ). A top end ( 240 ) of the shaft connects to a fan blade set. A free bottom end ( 242 ) of the shaft extends through the bearing into the central hole. A counter plate ( 40 ) made of high abrasion resistant material is located to face and supportively engage the free bottom end of the rotary shaft. A damping spring ( 70 ) exerts a force resiliently urging the counter plate against the free bottom end of the rotary shaft. The damping structure is capable of providing a cushion to a collision between the shaft and the bearing.