Abstract:
The present invention provides a heat-dissipating device including a heat sink and a heat pipe. The heat sink has an end surface provided with a trough. The trough has an open side and a closed side. The heat pipe has a heat-absorbing surface and a heat-conducting surface corresponding to the open side and the closed side respectively. The heat-conducting surface and the heat-absorbing surface are not brought into contact with the heat sink. The heat is directly absorbed by the heat pipe and then conducted to the heat sink for dissipation. With this arrangement, heat resistance of the heat-dissipating device is reduced to improve the heat-dissipating effect thereof.

Description:
This application claims the priority benefit of Taiwan patent application number 099115436 filed on May 14, 2010. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a heat-dissipating device, and in particular to a heat-dissipating device, whereby manufacturing cost is saved and heat resistance is reduced. 
     2. Description of Prior Art 
     Currently, heat pipe is a heat-conducting element widely used in electronic apparatuses and electronic elements. In general, the interior of the heat pipe is filled with a heat-conducting medium of good flowability, high heat of vaporization, low boiling point and stable chemical properties, such as water, ethanol, acetone or the like. The inner surfaces of the heat pipe are usually formed with a wick structure having a lot of protrusions. 
     In operation, one of the heat pipe acts as an evaporating section connected to a base of an electronic element, and the other end of the heat pipe acts as a condensing section assembled with a plurality of heat-dissipating fins. With this arrangement, when the evaporating section of the heat pipe is heated, the heat-conducting medium located in the evaporating section is vaporized to absorb a lot of latent heat of evaporation. As a result, the temperature of the base can be lowered. Then, the vapor-phase heat-conducting medium diffuses to the condensing section. The vapor-phase heat-conducting medium condenses into its liquid phase to release a lot of latent heat of condensation and flows back to the evaporating section through the wick structure. The heat-dissipating fins assembled with the condensing section dissipate the latent heat of condensation to the outside. 
     Please refer to  FIG. 1 , which is an exploded perspective view showing a conventional heat-dissipating device. The heat-dissipating device  3  is constituted of a heat sink  31  having fins, a base  32  and at least one heat pipe  33 . The heat sink  31  has a heat-absorbing portion  311  and a heat-dissipating portion  312 . The heat-absorbing portion  311  is adhered to the base  32 . One end of the heat pipe  33  is disposed between the heat-absorbing portion  311  and the base  32 . The other end of the heat pipe  33  is disposed through the heat-dissipating portion  312 . The heat-dissipating device  3  is brought into thermal contact with the base  32  to absorb the heat generated by a heat source  4 . The heat is conducted from the base  32  to the heat sink  31  and the heat pipe  33 , and then the heat is conducted from the heat pipe  33  to the heat-dissipating portion  312  of the heat sink  31 . By this structure, the heat-dissipating efficiency of the whole heat-dissipating device can be improved. 
     The base  32  of the conventional heat-dissipating device  3  has the following functions. The base  32  is combined with the heat sink  31  to directly conduct the heat to the heat-dissipating portion  312  of the heat sink  31 . Further, one side of the base  32  is provided with at least one groove  321  for allowing the heat pipe  33  to be received in and combined with the heat sink  31  because the heat pipe  33  is formed into a cylindrical pipe and unable to contact the heat source  4  properly. With the base  32  being brought into thermal contact with the heat source  4  to absorb the heat generated by the heat source  4 , the heat can be conduct from the base  32  to the heat sink  31  and the heat pipe  33 . 
     Since a gap is inevitably formed between two connected heat-dissipating elements, heat resistance is generated between these two heat-dissipating elements. In order to reduce the heat resistance, these two heat-dissipating elements can be soldered together by electrical-conductive solder. However, when a plurality of heat-dissipating elements is assembled together, the heat-dissipating efficiency of the whole structure is insufficient. On the other hand, it takes more time to assemble the plurality of heat-dissipating elements together, which undesirably raises the manufacturing cost. 
     Further, the combination of the base and the heat sink makes the whole heat-dissipating device bulky and unable to be moved easily. Also, such a large-sized heat-dissipating device occupies more space, so that the application thereof is limited. 
     According to the above, the conventional heat-dissipating device has drawbacks as follows: (1) higher cost; (2) more working hours for assembly; (3) unable to be used in a smaller space; and (4) low in heat-conducting and heat-dissipating efficiency. 
     SUMMARY OF THE INVENTION 
     A primary objective of the present invention is to provide a heat-dissipating device, whereby the heat resistance thereof is reduced. 
     Another objective of the present invention is to provide a heat-dissipating device, whereby the manufacturing cost thereof is reduced. 
     A further objective of the present invention is to provide a heat-dissipating device, which can be assembled easily. 
     In order to achieve the above objectives, the present invention is to provide a heat-dissipating device including a heat sink and at least one heat pipe. The heat sink is made by superposing a plurality of heat-dissipating fins and has a heat-dissipating portion and a heat-absorbing portion. The heat-absorbing portion has an end surface. The end surface is provided with a trough. One side surface of the heat-absorbing portion is provided with at least one through-hole in communication with both sides of the trough. The heat pipe has a heat-absorbing end and a heat-dissipating end. The heat-absorbing end has a heat-absorbing surface and a heat-conducting surface. The heat-absorbing surface is adjacent to the heat-conducting surface. The heat-absorbing end of the heat pipe is inserted into the through-hole. The heat-conducting surface is positioned in the trough in such a manner that the heat-conducting surface is not brought into contact with the heat sink. The heat-dissipating end is disposed through the heat-dissipating portion. 
     By this structure, the heat pipe absorbs the heat generated by a heat-generating element and conducts the heat to the heat-dissipating fins. Thus, the heat resistance and the manufacturing cost are reduced while an excellent heat-dissipating effect is achieved. Further, the heat sink can be made with reduced amount of materials, thereby making the heat sink to have a smaller weight and reducing the material cost. 
     According to the above, the present invention has advantages as follows: (1) reduced manufacturing cost; (2) smaller weight; (3) smaller heat resistance; and (4) less working hours and rapid assembly. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view showing a conventional heat-dissipating device; 
         FIG. 2  is an exploded perspective view showing a heat-dissipating device according to a first embodiment of the present invention; 
         FIG. 3  is an assembled perspective view showing the heat-dissipating device according to the first embodiment of the present invention; 
         FIG. 4  is an assembled perspective view showing the heat-dissipating device according to a second embodiment of the present invention; 
         FIG. 5  is an assembled perspective view showing the heat-dissipating device according to a third embodiment of the present invention; 
         FIG. 6  is an assembled perspective view showing the heat-dissipating device according to a fourth embodiment of the present invention; 
         FIG. 7  is an assembled perspective view showing the heat-dissipating device according to a fifth embodiment of the present invention; 
         FIG. 8  is an assembled perspective view showing the heat-dissipating device according to a sixth embodiment of the present invention; 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The above objectives and structural and functional features of the present invention will be described in more detail with reference to preferred embodiment thereof shown in the accompanying drawings 
       FIG. 2  is an exploded perspective view showing a heat-dissipating device according to a first embodiment of the present invention, and  FIG. 3  is an assembled perspective view showing the heat-dissipating device according to the first embodiment of the present invention. As shown in these figures, the heat-dissipating device  1  includes a heat sink  11  and at least one heat pipe  12 . 
     The heat sink  11  is constituted by superposing a plurality of heat-dissipating fins  2 . The heat sink  11  has a heat-dissipating portion  111  and a heat-absorbing portion  112 . The heat-absorbing portion  111  has an end surface  113 . The end surface  113  is provided with a trough  115 . One side surface of the heat-absorbing portion  112  is provided with at least one through-hole  116  in communication with both sides of the trough  115 . The heat-dissipating portion  111  is connected to the heat-absorbing portion  112 . The heat-dissipating portion  111  is formed by extending from one side of the heat-absorbing portion  112  away from the heat-absorbing portion  112 . The heat-dissipating portion  111  is provided with at least one hole  1111 . 
     The heat pipe  12  has a heat-absorbing end  121  and a heat-dissipating end  122 . The heat-absorbing end  121  has a heat-absorbing surface  1211  and a heat-conducting surface  1212 . The heat-absorbing surface  1211  is adjacent to the heat-conducting surface  1212 . The heat-absorbing end  121  of the heat pipe  12  is inserted into the through-hole  116  in such a manner that the heat-conducting surface  1212  is positioned to face outwardly of the trough  115  and not brought into contact with the heat sink  11 . The heat-dissipating end  122  is disposed through the heat-dissipating portion  111 . 
     The heat-dissipating device is brought into contact with at least one heat-generating element  5  to conduct the heat generated by the heat-generating element  5 . The heat-conducting surface  1211  of the heat pipe  12  is brought into thermal contact with the heat-generating element  5  directly. 
     Please refer to  FIG. 4 , which is an assembled perspective view showing the heat-dissipating device according to the second embodiment of the present invention. As shown in this figure, the structural relationship among respective components of the second embodiment is substantially the same as that of the first embodiment, so that the redundant description is omitted for simplicity. The difference between the second embodiment and the first embodiment is pointed out as follows. The heat sink  11  further has a first portion  117 , a second portion  118 , and a third portion  119 . The first portion  117  and the third portion  119  are provided on both ends of the second portion  118 . Of course, the relative position among these three portions may be changed based on practical demands. The thickness of the heat-dissipating fin  2  located in the first portion  117  and the third portion  119  is larger than that of the heat-dissipating fin  2  located in the second portion  118 . Alternatively, the heat-dissipating fin may be made of a material of a larger structural strength to thereby increase the strength of the whole heat-dissipating device  1 . 
     Please refer to  FIGS. 5 and 6 , which are assembled perspective views showing the heat-dissipating device according to the third and fourth embodiments of the present invention respectively. As shown in this figure, the structural relationship among respective components of the third and fourth embodiments is substantially the same as that of the first embodiment, so that the redundant description is omitted for simplicity. The difference between the third and fourth embodiments and the first embodiment is pointed out as follows. The heat-dissipating device  11  has a first reinforcement portion  13  and a second reinforcement portion  14 . The first reinforcement portion  13  and the second reinforcement portion  14  are provided on both ends of the heat sink  11  for increasing the structural strength of the heat sink  11 . Further, the difference between the third embodiment and the fourth embodiment lies in that the first reinforcement portion  13  and the second reinforcement portion  14  of the third embodiment (as shown in  FIG. 5 ) are configured to reinforce the short sides of the heat sink  1 , while the first reinforcement portion  13  and the second reinforcement portion  14  of the fourth embodiment (as shown in  FIG. 6 ) are configured to reinforce the long sides of the heat sink  1 . Thus, the relative angle shift between the reinforcement portions  13  and  14  of the third embodiment and those of the fourth embodiment is 90 degrees. 
     Please refer to  FIGS. 7 and 8 , which are assembled perspective views showing the heat-dissipating device according to the fifth and sixth embodiments of the present invention respectively. As shown in this figure, the structural relationship among respective components of the fifth and sixth embodiments is substantially the same as that of the first embodiment, so that the redundant description is omitted for simplicity. The difference between the fifth and sixth embodiments and the first embodiment is pointed out as follows. The heat-dissipating device  11  has at least one first reinforcement portion  13 , at least one second reinforcement portion  14  and at least one third reinforcement portion  15 . The first reinforcement portion  13  and the second reinforcement portion  14  are provided on both sides of the third reinforcement portion  15 . The heat-dissipating fins  2  are provided between the third reinforcement portion  15  and the first reinforcement portion  13  as well as between the third reinforcement portion  15  and the second reinforcement portion  14 . The first, second and third reinforcement portions  13 ,  14  and  15  are configured to increase the structural strength of the heat sink  11 . Further, the difference between the fifth embodiment and the sixth embodiment lies in that the first reinforcement portion  13 , the second reinforcement portion  14  and the third reinforcement portion  15  of the fifth embodiment (as shown in  FIG. 7 ) are configured to reinforce the short sides of the heat sink  1 , while the first reinforcement portion  13 , the second reinforcement portion  14  and the third reinforcement portion  15  of the sixth embodiment (as shown in  FIG. 8 ) are configured to reinforce the long sides of the heat sink  1 . Thus, the relative angle shift between the reinforcement portions  13 ,  14  and  15  of the fifth embodiment and those of the sixth embodiment is 90 degrees. 
     Please refer to  FIGS. 5, 6, 7, 8  again. As shown in these figures, the first reinforcement portion  13  has a first connecting portion  131 . The first connecting portion  131  has a first connecting end  1311  and a first connecting groove  1312 . The second reinforcement portion  14  has a second connecting portion  141 . The second connecting portion  141  has a second connecting end  1411  and a second connecting groove  1412 . The third reinforcement portion  15  has a third connecting portion  151 . The third connecting portion  151  has a third connecting end  1511  and a third connecting groove  1512 . The first connecting end  1311  of the first reinforcement portion  13 , the second connecting end  1411  of the second reinforcement portion  14 , and the third connecting end  1511  of the third reinforcement portion  15  are inserted into the first connecting groove  1312  of the first reinforcement portion  13 , the second connecting groove  1412  of the second reinforcement portion  14 , and the third connecting groove  1512  of the third reinforcement portion  15  respectively. In this way, the first reinforcement portion  13 , the second reinforcement portion  14 , and the third reinforcement portion  15  can be assembled together. 
     Further, it is apparent that the heat-dissipating device of the present invention may be made of the aforesaid reinforcement portions completely. The reinforcement portion (any of the first reinforcement portion  13 , the second reinforcement portion  14 , and the third reinforcement portion  15 ) is made of heat-conductive materials such as metal or non-metal. 
     Although the present invention has been described with reference to the foregoing preferred embodiments, it will be understood that the invention is not limited to the details thereof. Various equivalent variations and modifications can still occur to those skilled in this art in view of the teachings of the present invention. Thus, all such variations and equivalent modifications are also embraced within the scope of the invention as defined in the appended claims.