Abstract:
A heat-dissipating assembly utilizes a heat conductor having a high thermal conductivity to stagedly and effectively dissipate the heat to the surrounding environment. The heat-dissipating assembly includes a plurality of heat portions, at least one fan being disposed on the surface or side of the heat-dissipating portions, and a heat conductor having a high thermal conductivity connected within the plurality of the heat-dissipating portions.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    (a) Field of the Invention  
           [0002]    The invention relates to a heat-dissipating assembly and, more particularly, to a multi-level heat sink for dissipating heat in electronic products (for instance, CPUs of computers), which can effectively dissipate heat generated by the electronic products to the surrounding environment.  
           [0003]    (b) Description of the Related Art  
           [0004]    Following continuous improvements in performance of electronic devices, heat-dissipating assemblys or systems have become indispensable components. If the heat generated by individual components within the electronic device cannot be appropriately dissipated, in a less serious situation, the performance thereof is reduced, and in a more serious situation, the electronic device may be burnt and damaged. As a result, the surfaces or sides of the electronic component (for instance, the CPU of a computer) which produced a great amount of heat is generally mounted on a heat sink so as to dissipate the generated heat.  
           [0005]    Conventionally, a heat-dissipating assembly  1  as shown in FIG. 1 is mounted on the surface of the heat-generating component (for instance, a CPU) to dissipate the heat generated in the component. An axial fan  12  is mounted on an upper surface of a heat sink  11 , and a bottom surface  111  of the heat sink  11  is mounted on the CPU. The heat generated during the operation of the CPU is rapidly transferred to the heat sink  11 , and by means of air flow from the axial fan  12 , the accumulated heat at the heat sink  11  is dissipated.  
           [0006]    However, if the heat sink  11  is made too high, the heat-dissipation effect is poor. Further, in the development or improvement of the heat sink, the fins of the heat sink cannot be optionally and unrestrictedly extended or lengthened. These methods not only affect the flowrate and the air pressure of the fan, but also affect the design of the fin thickness. Thus, it is an important subject of the invention to provide a heat-dissipating assembly which can effectively dissipate heat generated by the electronic components to the surrounding environment.  
         SUMMARY OF THE INVENTION  
         [0007]    Accordingly, it is an object of the invention to provide a heat-dissipating assembly, using a heat conductor with a high thermal conductivity and to stagedly and effectively dissipate the heat to the surrounding environment.  
           [0008]    The multiple-level heat-dissipating assembly in accordance with the invention includes a plurality of heat-dissipating portions, at least one fan mounted on a surface or a side of the plurality of the heat-dissipating portions, and at least one heat conductor with a high thermal conductivity connected within the plurality of heat-dissipating portions.  
           [0009]    Preferably, each of the plurality of heat-dissipating portion includes a plurality of fins, and the fins are made from a material selected from the group consisting of aluminum, an aluminum alloy, copper, a copper alloy and a mixture of the above.  
           [0010]    Preferably, the plurality of heat-dissipating portions are disposed by stacking form up to bottom or in a left and right arrangement (i.e. vertically or horizontally arranged) and are coupled with a bridge portion. The plurality of heat-dissipating portions and the bridge portion are integrally formed as a unit. The heat conductor is inserted in the plurality of heat-dissipating portions and the bridge portion.  
           [0011]    Preferably, the heat conductor is a heat pipe, and is made from a material selected from the group consisting of gold, silver, aluminum, copper and a mixture of the above. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]    [0012]FIG. 1 is a perspective view of a conventional heat-dissipating assembly.  
         [0013]    [0013]FIG. 2 is a perspective view of a heat-dissipating assembly in accordance with a preferred embodiment of the invention.  
         [0014]    [0014]FIG. 3 is a side view of the heat-dissipating assembly in FIG. 2. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0015]    Referring to FIG. 2 illustrating a heat-dissipating assembly  2  of the invention, the heat-dissipating assembly  2  includes a first heat-dissipating portion  21 , a second heat-dissipating portion  22 , a bridge portion  23 , and two fans  24 ,  25 . The first heat-dissipating portion  21  has a bottom surface mounted on a surface of a heat-generating component, for instance, a CPU (not shown). The second heat-dissipating portion  22  is stacked over the first heat-dissipating portion  21  by means of the bridge portion  23 . The two fans  24 ,  25  are disposed on the first heat-dissipating portion  21  and the second heat-dissipating portion  22 , respectively. The first heat-dissipating portion  21  and the second heat-dissipating portion  22  are respectively provided with a plurality of fins to increase the heat-dissipating area thereof. The fins are made from aluminum, an aluminum alloy, copper, a copper alloy, or a mixture thereof. The first and second heat-dissipating portion  21 ,  22  and the bridge portion  23  can be made integrally as a unit.  
         [0016]    Additionally, the heat-dissipating assembly  2  further includes a heat conductor  26  having a high thermal conductivity, which is connected within the first heat-dissipating portion  21  and the second heat-dissipating portion  22 . The heat conductor  26  is inserted into the second heat-dissipating portion  21 , the bridge portion  23  and the bottom portion of the first heat-dissipating portion  21 , as shown in FIG. 3. The heat conductor  26  can be a heat pipe, which can be made from gold, silver, aluminum, copper or the mixtures of the above.  
         [0017]    Since the bottom surface of the first heat-dissipating portion  21  is to be mounted on a heat-generating element (not shown), the heat generated during the operation of the heat-generating element will be rapidly transferred to the first heat-dissipating portion  21 . In addition, a part of the heat will be dissipated together with the air flow of the axial fan  24  positioned at the top of the first heat-dissipating portion  21 . The remaining of the heat will be rapidly transferred to the second heat-dissipating portion  22  by means of the heat conductor  26 , and is then dissipated to the surrounding environment through the air flow of the axial fan  25  positioned at the top of the second heat-dissipating portion  22 . Since the air flow can pass through the space between the first heat-dissipating portion  21  and the second heat-dissipating portion  22  to the fan  24 , the heat generated by the heat-generating component is effectively and rapidly dissipated.  
         [0018]    In addition, the heat-dissipating assembly  2  further includes a control element mounted therein or outside. When the fan  24  does not function, the control element will output a signal to increase the rotational speed of the fan  25  so as to maintain the required heat-dissipating effect, or vice versa.  
         [0019]    In this embodiment, the two-level heat-dissipating assembly makes use of a thermal conductor having a high thermal conductivity as a medium. The lower portion of the heat-dissipating assembly is a heat-dissipating module and the upper portion is another heat-dissipating module. The lower portion effectively dissipates a part of the heat, and through the medium with a high thermal conductivity, the remaining of the heat is effectively transferred to the upper portion and dissipated therefrom. It is obvious that the heat-dissipating assembly in accordance with the invention does not restrict to the two-level stack, it can be a three-level stack. As for the fans used in the heat-dissipating assembly, it is not restricted to the axial fans as shown in FIG. 2, centrifugal fans can also be used based on the application of the heat-dissipating assembly.  
         [0020]    In view of the above, the invention uses a thermal conductor having a high thermal conductivity to transfer heat, and uses a multi-level way to stagedly transfer the heat to the surrounding environment. Except that a plurality of heat-dissipating portions of the multi-level heat-dissipating device are stacked in a vertical array, they can also be arranged in a horizontal array. Thus, the object to rapidly and effectively transfer heat can be achieved.  
         [0021]    While the invention has been particularly described, in conjunction with a specific preferred embodiment, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. It is therefore contemplated that the appended claims will embrace any such alternatives, modifications and variations as falling within the true scope and spirit of the invention.