Patent Publication Number: US-2010122795-A1

Title: Heat dissipation device

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The disclosure relates generally to heat dissipation devices and, more particularly, to a heat dissipation device having heat pipes and a mounting member for mounting the heat pipes on a bottom of the heat dissipation device. 
     2. Description of Related Art 
     Computer electronic components, such as central processing units (CPUs), generate great amounts of heat during normal operation. If the heat is not properly dissipated, it can deteriorate an operational stability of the electronic components and damage associated electronic devices. Thus, the heat must be removed quickly to ensure normal operation of these electronic components. A heat dissipation device is often attached to a surface of a CPU to remove heat therefrom. 
     A typical heat dissipation device attached to a CPU includes a base, a plurality of fins arranged on the base, and a plurality of heat pipes extending in the base and the fins. A plurality of grooves is defined in the base, and a plurality of holes is defined in the fins. Each heat pipe has a bent configuration and includes an evaporating section received in a corresponding groove of the base and a condensing section extending from the evaporating section. The condensing section is inserted into a corresponding hole of the fins. However, the heat pipes are often directly secured in the grooves of the base by soldering or adhering, and results in a poor stability between the heat pipes and the base, particularly when the number of the heat pipes increases. Additionally, when the base of the heat dissipation device has a small contacting surface with the heat pipes and a large space between the base and the fins is required, the heat pipes directly attached to the base can not satisfy the demand, whereby a mounting member for reliably and securely mounting the heat pipes on the base is needed. 
     What is needed, therefore, is a heat dissipation device with an enhanced mounting member. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the present disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
         FIG. 1  is an exploded, isometric view of a heat dissipation device in accordance with an embodiment of the present disclosure. 
         FIG. 2  is an inverted view of the heat dissipation device in  FIG. 1 . 
         FIG. 3  is a partially assembled view of the heat dissipation device in  FIG. 1 . 
         FIG. 4  is an assembled view of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Referring to  FIGS. 1-4 , a heat dissipation device in accordance with one embodiment of the present invention comprises a heat sink  10 , a plurality of heat pipes  20 ,  50  thermally extending in the heat sink  10 , a heat-conducting plate  30  attached to the heat pipes  20  and a mounting member  40  located between the heat sink  10  and the heat-conducting plate  30  for mounting the heat pipes  20  on the heat-conducting plate  30 . The heat-conducting plate  30  is adapted for removing heat from a first heat-generating electronic component (not shown) attached to a bottom surface of the heat-conducting plate  30 . 
     The heat sink  10  comprises a plurality of fins  12  substantially parallel to and stacked with each other. Each fin  12  may be formed from a metal sheet with high heat conductivity, such as an aluminum or a copper sheet. Each fin  12  defines a plurality of through holes  120  therein, for extension of the heat pipes  20 . 
     The plurality of heat pipes  20 ,  50  comprises three first heat pipes  20  and a second heat pipe  50  spaced from the first heat pipes  20 . Each first heat pipe  20  comprises an evaporating section  22 , a condensing section  24 , and a curving section  26  connecting the evaporating section  22  and the condensing section  24 . The evaporating sections  22  are parallel and juxtaposed with each other. The condensing sections  24  are substantially perpendicular to the evaporating sections  22  and extend into the through holes  120  of the heat sink  10 . The curving sections  26  of the two outermost first heat pipes  20  extend away from the middle one of the first heat pipes  20 . The second heat pipe  50  comprises a heat-absorbing portion  52  and a pair of heat-dissipating portions  54  extending substantially perpendicularly from opposite ends of the heat-absorbing portion  52 . The heat-absorbing portion  52  is substantially parallel to the evaporating sections  22  of the first heat pipes  20  and the heat-dissipating portions  54  are substantially parallel to the condensing sections  24  of the first heat pipe  20 . The heat-dissipating portions  54  extend into the heat sink  10 . 
     The heat-conducting plate  30  may have a rectangular shape and may be made of copper or copper alloy. The heat-conducting plate  30  defines three receiving slots  32  in a top surface, for receiving the evaporating sections  22  of the first heat pipes  20 . The three receiving slots  32  are located in a middle portion of the top surface of the heat-conducting plate  30  and substantially parallel to each other. A bottom surface of the heat-conducting plate  30  is attached to the first heat-generating electronic component. 
     The mounting member  40  comprises a mounting base  42  and a mounting board  44  engaging with the mounting base  42  to fix the first heat pipes  20  to the heat-conducting plate  30 . The mounting base  42  may be rectangular and has an area larger than an area of the heat-conducting plate  30  so as to cover the heat-conducting plate  30 . An opening  420 , corresponding to the receiving slots  32  of the heat-conducting plate  30 , is defined in a center portion of the mounting base  42 . A pair of strips  421  is formed at opposite inner lateral sides of the opening  420 , for pressing the heat-conducting plate  30  towards the first heat-generating electronic component. Each strip  421  defines a mounting hole  422  in a center portion, for extension of a screw  80 . The mounting base  42  further comprises a fixing flange  424  extending substantially perpendicularly from a long lateral side thereof, for facilitating to engage with the mounting board  44 . An elongated slot  426  is defined in a top surface of the mounting base  42 , adjacent to the fixing flange  424 , for receiving the heat-absorbing portion  52  of the second heat pipe  50  therein. 
     The mounting board  44  may be strip-shaped and engages with the mounting base  42  to fix the first heat pipes  20  on the heat-conducting plate  30  and the second heat pipes  50  on the mounting base  42 . The mounting board  44  comprises a projecting part  440  extending substantially perpendicularly and downwardly from a short lateral side edge thereof, for clasping the fixing flange  424  of the mounting base  42 . Three grooves  442  corresponding to the receiving slots  32  of the heat-conducting plate  30  are defined in a bottom surface of the mounting board  44 , for receiving the evaporating sections  22  of the first heat pipes  20 . A pair of screw holes  444  in alignment with the mounting holes  422  of the mounting base  42  is defined in the mounting board  44 , adjacent to the grooves  442  and, for extension of the screws  80  therethrough to secure the mounting board  44  to the mounting base  42 . 
     In operation, the mounting base  42  is located between the heat pipes  20 ,  50  and the heat-conducting plate  30 , wherein the heat pipes  20 ,  50  extend into the heat sink  10 . The strips  421  of the mounting base  42  are mounted on opposite side edges of the heat-conducting plate  30 , for example, by soldering or adhering. The evaporating sections  22  of the first heat pipes  20  extending through the opening  420  of the mounting base  42  are received in the receiving slots  32  of the heat-conducting plate  30 , for example, by soldering or adhering. The mounting board  44  spans the evaporating sections  22  of the first heat pipes  20  and the heat-absorbing portion  52  of the second heat pipe  50 , with the projecting part  440  abutting against the fixing flange  424  of the mounting base  42 . The evaporating sections  22  of the first heat pipes  20  are pressed towards the heat-conducting plate  30  when the mounting board  44  is mounted on the mounting base  42  via the screws  80  extending through the mounting hole  422  and screwed into the screw holes  444 . Thus, the evaporating sections  22  of the first heat pipes  20  are kept in intimate contact with the top surface of the heat-conducting plate  30  and absorb heat generated by the first heat-generating electronic component attached to the bottom surface of the heat-conducting plate  30 . The heat-absorbing portion  52  of the second heat pipe  50  absorbs heat generated by a second heat-generating electronic component (not shown) attached to a bottom surface of the mounting base  42  adjacent to the fixing flange  424 . 
     Since the mounting member  40  having the mounting base  42  engaging with the mounting board  44  has a compact structure, a space between the heat sink  10  and heat-conducting plate  30  is larger, when the mounting member  40  secures the heat pipes to the heat-conducting plate  30 . Moreover, because of the mounting member  40 , the first heat pipes  20  are mounted on the heat-conducting plate  30 , thereby enabling the first heat pipes  20  to have an intimate contact with the heat-conducting plate  30 . Due to a provision of the mounting member  40 , stability of the first heat pipes  20  on the heat-conducting plate  30  greatly increases. In addition, the stability of the second heat pipe  50  is also increased. 
     It is believed that the present disclosure and its advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the disclosure or sacrificing all of its material advantages, the examples hereinbefore described merely being preferred or exemplary embodiments.