Patent Publication Number: US-2010108362-A1

Title: Electronic system with heat dissipation device

Description:
BACKGROUND 
     1. Technical Field 
     The present disclosure relates to an electronic system with a heat dissipation devices and, particularly, to an electronic system with a heat sink capable of being conveniently assembled to and disassembled from a printed circuit board. 
     2. Description of Related Art 
     A heat sink is usually placed in thermal contact with a heat generating electronic device, which is mounted on a printed circuit board (PCB), such as a central processing unit (CPU), and transfers heat through conduction away from the heat generating electronic device so as to prevent over-heating of the heat generating electronic device. 
     Conventionally, the heat sink and the PCB are assembled together by a number of screws. The screws may be assembled to and disassembled from the heat sink and the PCB one by one. This is very time-consuming and trouble. The PCB is prone to be destroyed by assembling or disassembling the heat sink repeatedly. 
     What is needed, therefore, is a heat dissipation device overcoming the above-described problems. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded, isometric view of an electronic system in accordance with an embodiment of the present disclosure. 
         FIG. 2  is a partly assembled view of the electronic system in  FIG. 1 . 
         FIG. 3  is an assembled view of the electronic system in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1-2 , an electronic system of the present disclosure comprises a printed circuit board  50  (PCB) and a heat dissipation device (not labeled) thermally contacting the PCB  50 . The PCB  50  comprises an electronic component  51 , two first hooks  531  and two second hooks  532  around the electronic component  51 . The heat dissipation device comprises a base  10  contacting the electronic component  51 , a heat sink  40  mounted on a top surface of the base  10 , a wire clip  30  is mounted on the base  10  and engaging with two first hooks  531  and two second hooks  532  which are around the electronic component  51  of the PCB  50 . 
     The heat sink  40  comprises a fin group  44  and four U-shaped heat pipes  42 . The fin group  44  is located at the top surface of the base  10 . The heat pipes  42  extend through the fin group  44  and are thermally connected to the base  10 . 
     The fin group  44  comprises a number of first fins  441  and a number of second fins  442 . The first and second fins  441 ,  442  are substantially parallel to each other and engage with each other via locking members (not labeled) formed at corners thereof. Air passages are defined between the first and second fins  441 ,  442 . Each of the first fins  441  and the second fins  442  is a rectangular sheet. A length of the second fin  442  is equal to that of the first fin  441 . A width of the second fin  442  is smaller than that of the first fin  441 . The second fins  442  are located at top of the first fins  441 . Right ends of the second fins  442  and right ends of the first fins  441  are coplanar. Thus, the first fins  441  and the second fins  442  cooperatively form an L-shaped configuration. 
     Each of the heat pipes  42  comprises two parallel heat-conductive sections  421  and a connecting section  423  interconnecting the two heat-conductive sections  421 . Four heat-conductive sections  421  of the two heat pipes  42  extend through the first and second fins  441 ,  442  from bottom to top. Four heat-conductive sections  421  of another two heat pipes  42  extend through the first fins  441  from bottom to top and are located beside the second fins  442 . The connecting sections  423  are located at a bottom end of the fin group  44 . 
     The base  10  is made of aluminum or copper. The top surface of the base  10  defines four parallel grooves  11  to receive the connecting sections  423  of the four heat pipes  42 . First and third grooves  11  are located near a right end of the base  10 , as viewed from  FIG. 1 . Second and fourth grooves  11  are located near a left end of the base  10 . Two baffling portions  13  extend upwardly from the right and left ends of a rear side of the base  10 , respectively. The two baffling portions  13  restrict the wire clip  30  therebetween. Two engaging portions  15  are mounted on the right and left ends of a front side of the base  10 , respectively. The engaging portion  15  comprises a rectangular mounting plate  151  and an L-shaped clasp  153  extending from a central portion of a lateral side of the mounting plate  151 . Two screws  155  extend through the mounting plate  151  and engage with the base  10  to mount the engaging portion  15  on the base  10 . The clasp  153  and the mounting plate  151  cooperatively define a U-shaped opening therebetween to receive the wire clip  30 . The two engaging portions  15  are mounted on the right and left ends of the base  10  with the two openings thereof facing to each other. The two clasps  153  of the two engaging portions  15  restrict the wire clip  30  therebetween. 
     The clip  30  is integrally made of a metal wire. The clip  30  comprises a first straight connecting portion  31 , two straight extending portions  32 , two straight second connecting portions  33 , two bended pressing portions  34 , two straight third connecting portions  35  and two operating portions  36 . One extending portion  32 , second connecting portion  33 , pressing portion  34 , third connecting portion  35  and operating portion  36  are connected to one end of the first connecting portion  31  in series. Similarly, the other extending portion  32 , second connecting portion  33 , pressing portion  34 , third connecting portion  35  and operating portion  36  are connected to another end of the first connecting portion  31  in series. 
     The extending portions  32  perpendicularly extend from opposite ends of the first connecting portion  31 . The first connecting portion  31  and the two extending portions  32  form a U-shaped configuration. The two second connecting portions  33  perpendicularly extend outwardly from rear ends of the two extending portions  32 , respectively, and are oriented toward opposite directions. The two pressing portions  34  extend rearwards from free ends of the two second connecting portions  33  respectively. The two third connecting portions  35  extend inwardly from two free ends of the two pressing portions  34 . The two operating portions  36  extend perpendicularly and rearwards from two free ends of the two third connecting portions  35  respectively. 
     Each of the pressing portion  34  includes a first section close to the second connecting portions  33 , a second section close to the third connecting portions  35 , and a downward protruded portion  344  connected between the first and second sections. When the clip  30  is assembled to the base  10 , the two first sections of the two opposite pressing portions  34  engage with the two clasps  153  of the two engaging portions  15  of the base  10 , and the two second sections thereof are restricted between the two baffling portions  13  of the base  10 . Thus, the two pressing portions  34  of the clip  30  are restricted regarding lateral movement thereof. 
     The first hooks  531  of the printed circuit board  50  engage with the two second connecting portions  33  of the wire clip  30  and the second hooks  532  engage with the two third connecting portions  35 . The two first hooks  531  are positioned at a front side of the PCB  50 , and the two second hooks  532  are positioned at a rear side of the PCB  50 . When the assembly of the clip  30  and the base  10  is assembled to the PCB  50 , the two first hooks  531  clasp the two second connecting portions  33  and the two second hooks  532  clasp the two third connecting portions  35 . As a result, the assembly of the clip  30  and the base  10  is fixed on the PCB  50 . 
     Referring to  FIG. 3  also, in assembling, the operating portions  36  are pressed inwardly to enable the pressing portions  34  of the wire clip  30  be sandwiched between the clasps  153  of the engaging portions  15  and the baffling portions  13 . Thereafter, the operating portions  36  are released, and the first sections of the pressing portions  34  enter the clasps  153  of the engaging portions  15  and the second sections of the pressing portions  34  abut against the baffling portions  13  due to the resilience of the pressing portions  34 . The protruded portion  344  of the pressing portion  34  abuts against the top surface of the base  10 . Thus, the base  10  and the wire clip  30  are assembled together. 
     The heat-conductive sections  421  of the heat pipes  42  extend through the fin group  44  and the connecting sections  423  of the heat pipes  42  are received in the grooves  11  of the base  10 . Thus, the heat sink  40  is mounted on the base  10 . The base  10  thermally contacts with the electronic component  51  of the PCB  50 . The second connecting portions  33  of the clip  30  are clasped by the two first hooks  531  of the PCB  50 . The operating portions  36  of the clip  30  are pressed inwardly and downwardly until the third connecting portions  35  of the clip  30  are located at lower portions of the two second hooks  532  of the PCB  50 . The operating portions  36  are released, and the third connecting portions  35  are clasped by the two second hooks  532 . Therefore, the electronic system is assembled completely. 
     It is to be understood, however, that even though numerous characteristics and advantages of the disclosure have been set forth in the foregoing description, together with details of the structure and function of the disclosure, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.