Patent Publication Number: US-2010128438-A1

Title: Heat dissipation module

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the priority benefit of Taiwan application serial no. 97146015, filed Nov. 27, 2008. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of specification. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention generally relates to a heat dissipation module, in particular, to a heat dissipation module capable of enhancing the heat convection by a cooling unit. 
     2. Description of Related Art 
     With rapid development of electronic science and technology, and in order to satisfy consumers&#39; requirements, new electronic products are continuously coming forth in the market. So far as a computer is concerned, in order to make the computer system operate normally, electronic elements having high heat power in the computer system, such as Central Processing Unit (CPU), memory module, Graphics Processing Unit (GPU) and chipset, have to additionally provided with a heat dissipation module to bring extra heat energy out of the electronic elements, thus preventing the temperature of the electronic elements during operation from exceeding the normal upper service temperature. 
     Conventional heat dissipation module generally includes a heat sink used for contacting with a heating element. The heat sink includes a base and a plurality of fins connected to the base, in which the base is used for contacting with a surface of a electronic element requiring heat dissipation, receiving heat energy from the electronic element via a heat conducting manner, and conducting the heat energy to the fins on the base via the same manner. The fins are used for increasing heat dissipation area to improve the heat conducting efficiency of the heat sink. 
     Conventional heat dissipation module utilizes natural convection generated by a surface of the heat sink and forced air flow provided from the outside to improve the heat convection efficiency of the heat sink. That is, in addition to the heat sink, the heat dissipation module also includes a fan assembled at one side of the heat sink. The fan is used for providing forced air flow to improve the heat convection efficiency of the heat sink. However, as the fan of the conventional heat dissipation module may generate noise during operation, it is hard to compromise low noise and heat dissipation efficiency. In addition, for an environment in the presence of dust, the heat dissipation module with the fan is likely to absorb dust into the case of computer and then make the dust cover the heat sink, thus decreasing the heat dissipation efficiency. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention is directed to a heat dissipation module, for improving the heat dissipation performance by enhancing the convection efficiency. 
     The present invention provides a heat dissipation module suitable for a heating element. The heat dissipation module includes a first heat dissipation unit and a cooling unit. The heat dissipation unit includes a body suitable for being contacted with the heating element and a first heat dissipation fins set connected to the body. The cooling unit has a cooling surface and a heating surface, and is disposed on the first heat dissipation fins set by the cooling surface. 
     In an embodiment of the present invention, the above heat dissipation module further includes a second heat dissipation unit disposed on the cooling unit and contacted with the heating surface. 
     In an embodiment of the present invention, the second heat dissipation unit includes a second fins set. 
     In an embodiment of the present invention, the above heat dissipation module further includes a heat absorbing unit disposed between the cooling unit and the first heat dissipation fins set and contacted with the cooling surface. 
     In an embodiment of the present invention, the heat absorbing unit includes a third fins set. 
     In an embodiment of the present invention, an extension direction of the third fins set is substantially vertical to an extension direction of the first fins set. 
     In an embodiment of the present invention, in the above heat dissipation module, the cooling unit is a cooling chip. 
     In view of the above, the heat dissipation module of the present invention is capable of generating a low temperature region over the heat dissipation unit by the cooling unit to enhance the heat convection efficiency of the heat dissipation module. Moreover, the heat dissipation module of the present invention may substitute for the conventional fan heat dissipation module, so the electronic product can apply to more different environments, such as environments which must be noise-free or environments in the presence of dust. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
         FIG. 1  is an exploded view of a heat dissipation module according to an embodiment of the present invention. 
         FIG. 2  is an assembled view of the heat dissipation module of  FIG. 1 . 
         FIG. 3  is a cross-sectional view of the heat dissipation module of  FIG. 2  taken along line I-I. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     Reference will now be made in detail to the present embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts. 
       FIG. 1  and  FIG. 2  are an exploded view and an assembled view of a heat dissipation module according to an embodiment of the present invention respectively. Referring to  FIG. 1  and  FIG. 2 , the lower part of a heat dissipation module  100  is contacted with a heating element  50  to receive the heat energy from the heating element  50 . The heat dissipation module  100  includes a first heat dissipation unit  110  and a cooling unit  120 . The heat dissipation unit  110  includes a first body  112  and a first heat dissipation fins set  114 . The first heat dissipation fins set  114  is connected to the body  112 , and the first body  112  is suitable for being contacted with the heating element  50 . In this embodiment, the heating element  50  is, for example, a Central Processing Unit (CPU) or a graphics chip. 
       FIG. 3  is a cross-sectional view of the heat dissipation module of  FIG. 2  taken along line I-I. Referring to  FIG. 3 , the cooling unit  120  is a cooling chip, and the cooling unit  120  has a cooling surface  120   a  and a heating surface  120   b,  so as to absorb the heat from the outside by the cooling surface  120   a  and dissipate the heat out by the heating surface  120   b.  The cooling unit  120  is disposed on the first heat dissipation fins set  114  by the cooling surface  120   a  to receive the heat energy of the heat dissipation fins set  114 , thereby generating a low temperature region over the heat dissipation unit  110 . The air in the low temperature region falls because its density becomes larger after cooling, and the air surrounding the heat dissipation unit  110  rises because of the heating of the heating element  50 . In this way, the heat convection efficiency is enhanced by the density difference between the cold air and the hot air, thereby improving the heat dissipation performance. 
     In this embodiment, the heat dissipation module  100  may further include a second heat dissipation unit  130 . The second heat dissipation unit  130  is disposed on the cooling unit  120  and is contacted with the heating surface  120   b  to absorb the heat energy from the heating surface  120   b.  The second heat dissipation unit  130  includes a second body  132  and a second fins set  134 . The second fins set  134  is connected to the second body  132  to increase the heat dissipation area of the second heat dissipation unit  130 , thereby improving the heat dissipation performance. 
     In addition, the heat dissipation module  100  may further include a heat absorbing unit  140 . The heat absorbing unit  140  is disposed between the cooling unit  120  and the first heat dissipation fins set  114 , and is contacted with the cooling surface  120   a.  The heat absorbing unit  140  is, for example, a heat sink, and includes a third body  142  and a third fins set  144 . Referring to  FIG. 2 , the third fins set  144  extends on two sides, for example, and the first fins set  114  may extend at the gravity direction. That is, the extension direction A 1  of the third fins set  144  is substantially vertical to the extension direction A 2  of the first fins set  114 . In this way, the cooling unit  120  cools the heat absorbing unit  140  below and generates a low temperature region at the extension area of the third fins set  144 . 
     In view of the above, the heat dissipation module of this embodiment generates a low temperature region at the relatively high place of the heat dissipation module by a cooling element, and due to the density difference of the air, cold air in the low temperature region falls and hot air at the relatively lower place of the heat dissipation module rises. In this way, the heat convection efficiency is enhanced, thereby improving the heat dissipation performance. Moreover, the heat dissipation module of this embodiment may substitute for the conventional fan heat dissipation module, so the electronic product can apply to more different environments, such as environments which must be noise-free or environments in the presence of dust. 
     It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.