Abstract: A cooling fan includes a fan housing and a stator and an impeller received in the fan housing. The fan housing includes a frame and a mounting portion located in the frame. The stator is received in the frame and mounted to the mounting portion. The impeller is mounted to the stator and rotatable with respect to the stator. The impeller includes a hub and a plurality of blades extending radially and outwardly from the hub. Each of the blades includes an inner end connected with the hub and an outer end distant from the hub. Each of the blades forms a tab on the outer end at the end surface.

Abstract: A cooling fan includes a fan housing and a stator and an impeller received in the fan housing. The fan housing includes a frame and a mounting portion located in the frame. The stator is received in the frame and mounted to the mounting portion. The impeller is mounted to the stator and rotatable with respect to the stator. The impeller includes a hub and a plurality of blades extending radially and outwardly from the hub. Each of the blades includes an inner end connected with the hub and an outer end distant from the hub. Each of the blades forms a tab on the outer end at the end surface.

Abstract: A cooling fan includes a fan housing and a rotor. The fan housing includes an inner surface defining an inner space therein. The inner surface expands along a direction parallel to a central axis of the fan housing. The rotor is received in the inner space and surrounded by the inner surface of the fan housing. The rotor includes a hub and a plurality of rotary blades extending outwardly from the hub. Each of the rotary blades has an outer edge confronting the inner surface of the fan housing. The outer edge of each rotary blade slants towards the central axis of the fan housing.

Abstract: A fan assembly includes a first fan and a second fan mounted on the first fan. The first fan includes a plurality of locking units and a plurality of positioning dots extending upwardly therefrom. Each of the locking units includes a perpendicular portion and a horizontal portion. The second fan defines a plurality of through holes therein corresponding to the locking units of the first fan, and a plurality blind holes therein corresponding to the positioning dots of the first fan. Each of the locking units of the first fan extends into a corresponding through hole of the second fan with the horizontal portion thereof engaging with the second fan near an edge of the through hole. Each of the positioning dots of the first fan is received in a corresponding blind hole of the second fan.

Abstract: A cooling fan includes a base forming a central tube at a central portion thereof, a stator mounted around the central tube and a rotor rotatable relative to the stator. The central tube defines at least one engaging slot therein. The stator includes a stator core, an upper insulating frame attached to a top side of the stator core and a lower insulating frame attached to a bottom side of the stator core. The upper insulating frame forms a plurality of protrusion tabs extending inwardly from an inner circumferential surface of the upper insulating frame. The protrusion tabs extend into and engage in the at least one engaging slot to securely mount the stator core around the central tube.

Abstract: A heat dissipation device (1) includes an electric fan (20) and a heat sink (10). The fan includes a fan impeller (40) which includes a hub (41) and a plurality of blades (42) extending radially and outwardly from the hub (41). The hub (41) includes an upper portion (417) and a bottom portion (413). An air inlet (411) is formed near the upper portion (417) and an air outlet (412) is formed near the bottom portion (413). The blades (42) have portions on the bottom portion of the hub which are extended toward a center of the air outlet for driving more air to the center of the air outlet (412), whereby more air can flow to a center of the heat sink.

Abstract: A heat dissipation device (1) includes an electric fan (20) and a heat sink (10). The fan includes a fan impeller (40) which includes a hub (41) and a plurality of blades (42) extending radially and outwardly from the hub (41). The hub (41) includes an upper portion (417) and a bottom portion (413). An air inlet (411) is formed near the upper portion (417) and an air outlet (412) is formed near the bottom portion (413). The blades (42) have portions on the bottom portion of the hub which are extended toward a center of the air outlet for driving more air to the center of the air outlet (412), whereby more air can flow to a center of the heat sink.