Heat dissipation device

Abstract

A heat dissipation device includes a base, a fin group mounted on a top surface of the base, and a plurality of fasteners secured on the base. Each fastener includes a bolt extending through the base, and an elastic sleeve engaging with the bolt under the base. The sleeve defines a hole and the hole has a configuration such that the sleeve securely clasp the bolt. The bolt extends through the base and engages in the hole of the sleeve.

1 . A heat dissipation device adapted for dissipating heat generated by an electronic component mounted on a printed circuit board comprising:
 a base;   a fin group mounted on a top surface of the base; and   a plurality of fasteners secured on the base, each fastener comprising a bolt extending through the base and an elastic sleeve engaging with the bolt under the base;   wherein the sleeve defines a hole and the hole has a configuration such that the sleeve securely clasp the bolt, and the bolt extends through the base and engages in the hole of the sleeve.   
   
   
       2 . The heat dissipation device as claimed in  claim 1  further comprising a spring encircling the bolt of each of the fasteners, wherein the bolt has a head and a shaft extending from the head, and the spring is sandwich between the head of the bolt and the base. 
   
   
       3 . The heat dissipation device as claimed in  claim 2 , wherein the spring has an out diameter smaller than a diameter of the head and larger than a diameter of the shaft of the bolt of each of the fastener, and the diameter of the shaft is larger than that of the hole of the sleeve, the shaft extending through the base and engaging in the hole of the sleeve. 
   
   
       4 . The heat dissipation device as claimed in  claim 2 , wherein the base defines a plurality of counterbores receiving the fasteners therein, each counterbore having a first through hole located at a top portion of the base and a smaller second through hole located at a bottom portion of the base, a part of spring being received in the first through hole and the shaft of the bolt extending through the counterbore. 
   
   
       5 . The heat dissipation device as claimed in  claim 4 , wherein the sleeve has a diameter larger than that of the second through hole of the counterbore and is located under a bottom surface of the base. 
   
   
       6 . The heat dissipation device as claimed in  claim 1 , wherein the sleeve is made of elastic material. 
   
   
       7 . The heat dissipation device as claimed in  claim 1  further comprising a pair of heat pipes sandwiched between the fin group and the base. 
   
   
       8 . The heat dissipation device as claimed in  claim 7 , wherein each of heat pipe has a straight evaporating portion located at a centre of the base and two bent condensing portions extending from opposite ends of the evaporating portion, and a distance between the corresponding condensing portions is larger than that of between the evaporating portions. 
   
   
       9 . The heat dissipation device as claimed in  claim 7 , wherein each of the heat pipes is flattened and comprises a top surface, and the top surfaces of the heat pipes and the top surface of the base are coplanar. 
   
   
       10 . The heat dissipation device of  claim 8 , wherein the pair of heat pipes define an X-shaped configuration in the base. 
   
   
       11 . The heat dissipation device as claimed in  claim 1 , wherein the fin group comprises a plurality of fins and the fins are clasped each other by a clasp formed on a top edge of each of the fins. 
   
   
       12 . The heat dissipation device as claimed in  claim 11 , wherein each of the fins of the fin group further comprises an elongated flange formed on a bottom edge thereof, and the flange are assembled together to contact the top surface of the base. 
   
   
       13 . The heat dissipation device of  claim 1 , wherein the hole of the sleeve is rectangular in a cross section direction of the sleeve. 
   
   
       14 . The heat dissipation device of  claim 1 , wherein the sleeve comprises a base portion and mounting portion extending from the base, the hole extending through a centre of the mounting portion.