Heat dissipation device

Abstract

An exemplary heat dissipation device includes a centrifugal fan and a fin assembly. An air outlet is defined in the centrifugal fan. The fin assembly is located at the air outlet of the centrifugal fan. The fin assembly includes a first fin unit and two second fin units. The first fin unit includes a plurality of first fins made of a first material. Each of the second fin units includes a plurality of second fins made of a second material. A heat conductive efficiency of the first material exceeds that of the second material.

1 . A heat dissipation device comprising:
 a centrifugal fan defining an air outlet therein; and   a fin assembly located at the air outlet of the centrifugal fan, the fin assembly comprising a first fin unit and at least one second fin unit juxtaposed with the first fin unit in a line, the first fin unit comprising a plurality of first fins made of a first material, the at least one second fin unit comprising a plurality of second fins made of a second material;   wherein a heat conductive efficiency of the first material exceeds that of the second material.   
     
     
         2 . The heat dissipation device of  claim 1 , wherein the first material is copper, and the second material is aluminum. 
     
     
         3 . The heat dissipation device of  claim 2 , wherein the first fin unit faces the center of the air outlet of the centrifugal fan, the at least one second fin unit comprises two second fin units respectively facing two opposite outer portions of the air outlet of the centrifugal fan, and the first fin unit is located between the two second fin units. 
     
     
         4 . The heat dissipation device of  claim 3 , wherein a surface area of each of the first fins exceeds that of each of the second fins, and two recesses are respectively defined below the two second fin units. 
     
     
         5 . The heat dissipation device of  claim 2 , wherein a surface area of each of the first fins exceeds that of each of the second fins, and a recess is defined below the at least one second fin unit. 
     
     
         6 . The heat dissipation device of  claim 1 , further comprising a heat absorbing plate and a heat pipe, wherein one end of the heat pipe is attached to the heat absorbing plate, and an opposite end of the heat pipe is attached to the fin assembly. 
     
     
         7 . A heat dissipation device comprising:
 a centrifugal fan defining an air outlet therein; the centrifugal fan adapted for generating airflow and outputting the airflow from the air outlet; and   a fin assembly located at the air outlet of the centrifugal fan, the fin assembly comprising a first fin unit and at least one second fin unit juxtaposed with the first fin unit in a line, the first fin unit comprising a plurality of first fins made of a first material, the at least one second fin unit comprising a plurality of second fins made of a second material;   wherein a heat conductive efficiency of the first material exceeds that of the second material, and the airflow at the first fin unit exceeds that at the at least one second fin unit.   
     
     
         8 . The heat dissipation device of  claim 7 , wherein the first material is copper, and the second material is aluminum. 
     
     
         9 . The heat dissipation device of  claim 8 , wherein the first fin unit faces the center of the air outlet of the centrifugal fan, the at least one second fin unit comprises two second fin units respectively facing two opposite outer portions of the air outlet of the centrifugal fan, and the first fin unit is located between the two second fin units. 
     
     
         10 . The heat dissipation device of  claim 9 , wherein a surface area of each of the first fins exceeds that of each of the second fins, and two recesses are respectively defined below the two second fin units. 
     
     
         11 . The heat dissipation device of  claim 7 , further comprising a heat absorbing plate and a heat pipe, wherein one end of the heat pipe is attached to the heat absorbing plate, and an opposite end of the heat pipe is attached to the fin assembly. 
     
     
         12 . A heat dissipation device comprising:
 a centrifugal fan defining an air outlet therein; and   a fin assembly comprising a first fin unit and a pair of second fin units at opposite sides of the first fin unit, the first and second fin units arranged in line facing the air outlet of the centrifugal fan, the first fin unit protruding below the second fin units and being made of a first material having high heat conductivity, the second fin units being made of a second material having lower heat conductivity.