Heat dissipation device

Abstract

A heat dissipation device includes a heat sink, a fan including a fixing member, and a positioning member. The heat sink includes a supporting portion and a number of fins. The supporting portion defines a positioning hole including an access hole and a locking hole communicating with the access hole. The positioning member includes a neck connected to a bottom of the fan, and a head connected to a bottom end of the neck and having a diameter greater than a diameter of the neck. When fixing the fan, the head extends through the access hole, the fan is slid to move the neck into the locking hole, and the fixing member is fixed to the heat sink.

What is claimed is: 
     
         1 . A heat dissipation device, comprising:
 a heat sink comprising a supporting portion and a plurality of fins, the supporting portion defining a positioning hole, the positioning hole comprising an access hole, and a locking hole communicating with the access hole and less than the access hole in width;   a fan comprising a fixing member; and   a positioning member comprising a neck connected to a bottom of the fan, and a head connected to a bottom end of the neck and having a diameter greater than a diameter of the neck; and   wherein, when fixing the fan, the head extends through the access hole, the fan is slid to make the neck move into the locking hole hole, the fixing member is then fixed to the heat sink, to fix the fan to the heat sink.   
     
     
         2 . The heat dissipation device of  claim 1 , wherein a diameter of the head is less than the width of the access hole, but greater than the width of the locking hole, when the neck is engaged in the locking hole, the head abuts against a bottom of the supporting portion. 
     
     
         3 . The heat dissipation device of  claim 1 , wherein a protrusion protrudes from the supporting portion and defines an engaging hole, the fixing member comprises an inserting portion to detachably engage in the engaging hole. 
     
     
         4 . The heat dissipation device of  claim 1 , wherein the fan defines a depressed portion, the fixing member is mounted in the depressed portion. 
     
     
         5 . The heat dissipation device of  claim 4 , wherein the fixing member comprises a base fixed in the depressed portion, a shaft slidably extending through the base, and a spring fitted about the shaft, and an inserting portion connected to a bottom end of the shaft, the fan defines a receiving hole extending through a top side of the base and a bottom of the fan, a blocking portion is formed at the top of the base, opposite ends of the spring respectively abut against an inner surface of the blocking portion and the inserting portion, the spring biases the inserting portion to extend out of the receiving hole through the bottom of the fan to engage in an engaging hole defined in the supporting portion. 
     
     
         6 . The heat dissipation device of  claim 5 , wherein the fixing member further comprises an operation portion connected to a top end of the shaft, facilitating pull the inserting portion out of the engaging hole. 
     
     
         7 . The heat dissipation device of  claim 6 , wherein when the inserting portion is engaged in the engaging hole, the operation portion is received in the depressed portion.