Heat sink assembly

Abstract

A heat sink assembly includes a heat sink and two fixing members. The heat sink includes a board and a number of fins extending substantially perpendicularly up from the board. A first fixing portion and two second fixing portions at opposite sides of the first fixing portion are formed at each of opposite sides of the board. Each fixing member includes a driving portion, a fixing bolt, and two positioning poles. Each driving portion defines an installing hole and two positioning holes at opposite sides of the installing hole. The fixing bolts extend through the installing holes, the first fixing portions, and a circuit board to engage with the circuit board. The positioning poles are inserted into the second fixing portions and the positioning holes. A spring is fitted about each positioning pole and is sandwiched between the corresponding second fixing portion and the corresponding driving portion.

What is claimed is: 
     
         1 . A heat sink assembly to be mounted to a circuit board, the heat sink assembly comprising:
 a heat sink comprising a base board, a plurality of fins extending up from the base board, and two fixing portion sets extending from opposite sides of the base board, each fixing portion set comprising a first fixing portion and two second fixing portions at opposite sides of the first fixing portion, each first fixing portion and second fixing portion defining a through hole; and   two fixing members, each fixing member comprising a driving portion, a fixing bolt, two positioning poles, and two springs fitted about the positioning poles, each driving portion defining an installing hole and two positioning holes at opposite sides of the installing hole;   wherein the fixing bolts extend through the installing holes and the through hole of the first fixing portions and engage in the circuit board; the positioning poles are respectively inserted into the through holes of the second fixing portions and the positioning holes; each spring is sandwiched between a corresponding second fixing portion and a corresponding driving portion.   
     
     
         2 . The heat sink assembly of  claim 1 , wherein each first fixing portion is spaced from the corresponding second fixing portions substantially the same distances. 
     
     
         3 . The heat sink assembly of  claim 1 , wherein each positioning pole comprises an elongated body and a blocking portion protruding from a circumference of the elongated body to abut against a top of the corresponding second fixing portion, and each spring is sandwiched between a corresponding blocking portion and the driving portion. 
     
     
         4 . The heat sink assembly of  claim 1 , wherein each fixing bolt comprises a connecting pole, and a head and a tapered locking portion connected to opposite ends of the connecting pole, and the locking portion is pliable to extend through the corresponding installing hole. 
     
     
         5 . The heat sink assembly of  claim 4 , wherein a slot is defined in the locking portion.