Rotor for a cooling fan

Abstract

A rotor for a cooling fan has a hollow hub having an open lower end. A permanent magnet is received in the hub. A rod is received in the hub and extends downwards. Multiple vanes are evenly formed around the periphery of the hollow hub and extend radially. Multiple notches are respectively defined at edges of the vanes and adjacent to the hollow hub. When the airflow is compressed by the rotation of the vanes, the airflow can be led to a desired direction via the notches. Whereby, the pressures between adjacent vanes are even thereby preventing the collision between the airflow and interior components of the cooling fan, so that the noise is avoided.

1 . A rotor ( 10 ) for a cooling fan comprising: 
 a hollow hub ( 11 ) having an open lower end, a permanent magnet received in the hub ( 11 ), and a rod ( 111 ) axially received in the hub ( 11 ) and extending downwards;    multiple vanes ( 12 ) evenly formed around an outer periphery of the hollow hub ( 11 ) and extending radially; and    multiple notches ( 13 ) respectively defined in the vanes ( 12 ) and adjacent to the outer periphery of the hollow hub ( 11 ).    
   
   
       2 . The rotor ( 10 ) for the cooling fan as claimed in  claim 1 , wherein the notches ( 13 ) are defined in a top edge of the respective vanes ( 12 ).  
   
   
       3 . The rotor ( 10 ) for the cooling fan as claimed in  claim 2 , wherein a bevel ( 131 ) is formed at a bottom of each notch ( 13 ).  
   
   
       4 . The rotor ( 10 ) for the cooling fan as claimed in  claim 1 , wherein a bevel ( 131 ) is formed at a bottom of each notch ( 13 ).