Patent ID: 7094039
Filing Date: 2006-08-22
Classification: F04D,F05D

Abstract:
1. A heat-dissipating fan, comprising: an axle, having a cylindrical shape and made from a ceramic material; a bearing having a cylindrical wall, a top side and a bottom side, a disk-shaped base disposed under the bottom side, wherein a central hole is formed through the top side and the bottom side, wherein the axle is engaged in the central hole of the top side and the bottom side and extends down to the disk-shaped base and wherein the diameter of the axle is smaller than the inner diameter of the cylindrical wall forming a space between the axle and the cylindrical wall, and wherein an end of the axle engages the disk-shaped base; a rotor, including a motor casing, a plurality of blades and a magnetic bar, wherein the motor casing is a casing that has a down-facing opening and a blind hole at a central location of an interior of the motor casing for accommodating the axle, the blades being mounted on an external surface of the motor casing, and the magnetic bar being mounted inside the motor casing; and a stator, including a base, an upper coil frame, a lower coil frame, a coil and a silicon steel sheet, wherein an annular wall extends upward from a central portion of the base for mounting the bearing, the upper coil frame and the lower coil frame being mounted outside the annular wall, the silicon steel sheet being mounted between the upper and lower coil frames, a magnetic force center of the silicon steel sheet being at a level lower than that of the magnetic bar, and the coil being wrapped around the upper coil frame, the silicon steel sheet and the lower coil frame; wherein the surface of the base where the bearing and the axle contact each other is flat.