Heat dissipation device

Abstract

A heat dissipation device used for dissipating heat from an electronic device mounted on a printed circuit board (PCB), includes a heat sink contacting with the electronic device, a locking device mounted on the heat sink and securing the heat sink onto the PCB. The locking device comprises a supporting plate extending through the heat sink, two arms respectively and slidably fixed on two opposite ends of the supporting plate and two fastening devices respectively slidably fixed to the two arms. The two arms can move along a first direction about the heat sink, and the two fastening devices can move along a second direction about the arms, thereby aligning the two fastening devices with two through holes defined in the printed circuit board, respectively.

1 . A heat dissipation device for dissipating heat generated by an electronic device mounted on a printed circuit board, the heat dissipation device comprising:
 a heat sink; and   a locking device for mounting the heat sink on the printed circuit board, the locking device comprising two arms respectively slidably mounted at two opposite lateral sides of the heat sink and two fastening devices respectively slidably mounted to the two arms, wherein the two arms can move on the heat sink along a first direction, and the two fastening devices can move on the arms along a second direction different from the first direction.   
   
   
       2 . The heat dissipation device as claimed in  claim 1 , wherein the first direction is perpendicular to the second direction. 
   
   
       3 . The heat dissipation device as claimed in  claim 1 , wherein the locking device further comprises a supporting plate attached to the heat sink, two ends of the supporting plate being respectively located out of the two opposite lateral sides of the heat sink and respectively connecting the two arms. 
   
   
       4 . The heat dissipation device as claimed in  claim 3 , wherein each of the two arms comprises a first mounting portion fixed on a corresponding one of the two ends of the supporting plate and a second mounting portion, the two fastening devices being respectively inserted thought the second mounting portions of the arms. 
   
   
       5 . The heat dissipation device as claimed in  claim 4 , wherein the first mounting portion and the second mounting portion respectively define an elongate first through hole and an elongate second through hole, and the elongate first holes of the two arms can move over the supporting plate, and the two fastening devices can move along the second elongate through holes of the two arms. 
   
   
       6 . The heat dissipation device as claimed in  claim 5 , wherein the two ends of the supporting plate each define a threaded hole, a screw extending through the elongate first through hole of the first mounting portion and engaging in the threaded hole of the supporting plate. 
   
   
       7 . The heat dissipation device as claimed in  claim 4 , wherein the first mounting portion and second mounting portion are perpendicular to each other, the two arms each further comprising a connecting portion interconnecting the first mounting portion and the second mounting portion. 
   
   
       8 . The heat dissipation device as claimed in  claim 7 , wherein the first mounting portion and the second mounting portion are respectively located at two adjacent sides of the heat sink. 
   
   
       9 . The heat dissipation device as claimed in  claim 8 , wherein the connecting portion extends slantwise and downwardly from the first mounting portion to connect with the second mounting portion. 
   
   
       10 . The heat dissipation device as claimed in  claim 4 , wherein the two fastening devices each comprise a head, a shaft extending downwardly from the head, a retaining portion formed at a distal end of the shaft and a spring encircling the shaft, the spring being compressed between the head and a top surface of the second mounting portion, the shaft extending through the second mounting portion. 
   
   
       11 . The heat dissipation device as claimed in  claim 3 , wherein the heat sink comprises a plurality of fins connected together, and the first direction is parallel to the plurality of fins. 
   
   
       12 . The heat dissipation device as claimed in  claim 11 , wherein the plurality of fins defines a channel along the second direction, the supporting plate being inserted into the channel in the plurality of fins, a fan being mounted on a top of the heat sink. 
   
   
       13 . The heat dissipation device as claimed in  claim 11 , wherein the heat sink further comprises a heat pipe which comprises an evaporating section and a condensing section, the evaporating section being inserted into a center of a bottom of the plurality of fins and having a bottom surface coplanar with that of the plurality of fins, the condensing section being inserted into the plurality of fins and located above the evaporating section. 
   
   
       14 . A heat dissipation device comprising:
 a heat sink; and   a locking device for mounting the heat sink on a printed circuit board, comprising an arm movably attached to the heat sink and a fastening device movably attached to the arm, wherein the arm and the fastening device are movable along different directions to align the fastening device with a selected part of the printed circuit board, whereby the fastening device can be accurately secured with the selected part of the printed circuit board.   
   
   
       15 . The heat dissipation device as claimed in  claim 14 , wherein the arm is movable along a first direction perpendicular to a second direction along which the fastening device is movable. 
   
   
       16 . The heat dissipation device as claimed in  claim 14 , wherein the arm comprises a first mounting portion slidably mounted to the heat sink and a second mounting portion to which the fastening device is slidably attached. 
   
   
       17 . The heat dissipation device as claimed in  claim 16 , wherein the second mounting portion is located at a level lower than that where the first mounting portion is located. 
   
   
       18 . The heat dissipation device as claimed in  claim 15 , wherein the locking device further comprises a plate horizontally extending through the heat sink along the second direction, the arm being attached to an end of the plate which extends beyond the heat sink.