Abstract:
A heat dissipation apparatus includes an expansion base, an air duct, a fan, a heat sink, and a portable device. A number of air inlet slots is defined in the expansion base. A first air inlet opening and a number of diagonal air outlet slots are defined in the air duct. A third air inlet opening and a third air outlet opening are defined in the portable device. The fan generates airflow through the portable device in such a manner that airflow flows from the expansion base outside is sucked into and blown out of the air duct via a first airflow passage. The portable device guides airflow in and out of the portable device via a second airflow passage.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The present disclosure relates to a heat dissipation apparatus for an expansion base in portable devices. 
         [0003]    2. Description of Related Art 
         [0004]    Panel computers include expansion bases to insert expansion cards. However, panel computers generate large amounts of heat when connected to expansion bases, which may be a hazard and cause a reduction in the life of the panel computers. 
         [0005]    Therefore, there is a need for improvement in the art. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    Many aspects of the embodiments 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 embodiments. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
           [0007]      FIG. 1  is an isometric, exploded view of an embodiment of a heat dissipation apparatus for an expansion base. 
           [0008]      FIG. 2  is an enlarged view of a circled portion II of  FIG. 1 . 
           [0009]      FIG. 3  is an assembled view of the heat dissipation apparatus for an expansion base of  FIG. 1 . 
           [0010]      FIG. 4  is a cross-sectional view of the heat dissipation apparatus for an expansion base of  FIG. 3 , taken along line IV-IV. 
       
    
    
     DETAILED DESCRIPTION 
       [0011]    The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean “at least one.” 
         [0012]      FIGS. 1 and 2  show a heat dissipation apparatus, which includes an expansion base  10 , an air duct  20 , a fan  30 , and a portable device  40 . 
         [0013]    The expansion base  10  includes a base body  11 . A plurality of air inlet slots  12  is defined in one side of the base body  11 . A first inserting slot  13  and a second inserting slot  14  are defined in a top of the base body  11 . The first inserting slot  13  is substantially parallel to the second inserting slot  14 . 
         [0014]    The air duct  20  includes a duct body  21 . A first air inlet opening  22  is defined in a bottom of the duct body  21 . A plurality of air outlet slots  23  is diagonally defined in a top of the duct body  21 . A first air inlet channel defined by the first air inlet opening  22  is substantially parallel to a first air outlet channel defined by the plurality of air outlet slots  23 . The first air inlet opening  22  communicates with the plurality of air outlet slots  23 . In this embodiment, a length of the first inserting slot  13  is less than a length of the second inserting slot  14 . A length of the first inserting slot  13  is substantially equal to a length of the duct body  21 , and a width of the first inserting slot  13  is substantially equal to a thickness of the duct body  21 . A length of the second inserting slot  14  is substantially equal to a length of the portable device  40 , and a width of the second inserting slot  14  is substantially equal to a thickness of the portable device  40 . 
         [0015]    The fan  30  includes a shell  31  and a rotatable fan blade module  32 . A second air inlet opening  311  is defined in one side of the shell  31 . The shell  31  further defines a second air outlet opening  312  in a top of the shell  31 . The second air inlet opening  311  allows air to flow into the fan  30  along a first direction, which is in line with a rotating axle of the fan blade module  32 . The second air outlet opening  312  allows air to flow out of the fan  30  along a second direction, which is substantially perpendicular to the first direction. In this embodiment, a length of the second air outlet opening  312  is substantially equal to a length of the plurality of air outlet slots  23 . 
         [0016]    The portable device  40  includes a main body  41  and a cover plate  42 . The cover plate  42  is mounted on the main body  41 . A plurality of third air inlet openings  43  is defined in one side of the main body  41 . A plurality of third air outlet openings  44  is defined in a top of the main body  41 . A second air inlet channel defined by the plurality of third air inlet openings  43  is substantially perpendicular to a second air outlet channel defined by the plurality of third air outlet openings  44 . The plurality of third air inlet openings  43  communicates with the plurality of third air outlet openings  44 . A first heat dissipation element  411  and a second heat dissipation element  412  are mounted on the main body  41 . A heat sink  413  is mounted on the first heat dissipation element  411  and the second heat dissipation element  412  for transmitting heat. In this embodiment, the first heat dissipation element  411  is a CPU, and the second heat dissipation element  412  is a power control unit. 
         [0017]      FIGS. 1 to 3  show that in assembly, the fan  30  is fixed in the duct body  21  of the air duct  20 , such that the second air outlet opening  312  of the fan  30  is aligned with the plurality of air outlet slots  23  of the duct body  21 . The duct body  21  is received in the first inserting slot  13 , such that the first air inlet opening  22  of the air duct  20  communicates with an inside of the first inserting slot  13 . The heat sink  413  is mounted on the first heat dissipation element  411  and the second heat dissipation element  412 . The cover plate  42  is mounted on the main body  41  to cover the first heat dissipation element  411 , the second heat dissipation element  412 , and the heat sink  413 . The portable device  40  is received in the second inserting slot  14 . The cover plate  42  of the portable device  40  abuts against the duct body  21 . The plurality of air outlet slots  23  face the cover plate  42 . 
         [0018]      FIG. 4  shows that in operation, the first heat dissipation element  411  and the second heat dissipation element  412  generate large amounts of heat when the portable device  40  is powered on. The heat generated by the first heat dissipation element  411  and the second heat dissipation element  412  is transmitted to the heat sink  413 . A first amount of air from outside the expansion base  10  enters the portable device  40  via the plurality of third air inlet openings  43  or the plurality of third air outlet openings  44 . The first amount of air displaces some heat accumulated in the heat sink  413 . The heated first amount of air then exits from the portable device  40  through the plurality of third air outlet openings  44  or the plurality of third air inlet openings  43 . A second amount of air from outside the expansion base  10  is sucked into the fan  30  via the plurality of air inlet slots  12  and the second air inlet opening  311 . A speed of the second amount of air is increased when passing through the fan  30 . The second amount of air is blown out of the fan  30  through the second air outlet opening  312  toward the plurality of air outlet slots  23  of the air duct  20 . The second amount of air is diagonally blown out of the air duct  20  through the plurality of air outlet slots  23 . The second amount of air is blown toward the cover plate  42  of the portable device  40  to remove heat accumulated on the cover plate  42 . Therefore, a temperature of the portable device  40  is further decreased. 
         [0019]    In this embodiment, the duct body  21  of the air duct  20  is made of heat-conducting material. The heat accumulated on the cover plate  42  of the portable device  40  is partially transmitted to the duct body  21 . The second amount of air passes through the duct body  21  and removes the heat accumulated on the duct body  21 . Therefore, the three described modes of heat dissipation significantly improve a heat dissipation efficiency of the heat dissipation apparatus. 
         [0020]    Using a software application called ICEPAK to simulate the efficiency of the heat dissipation apparatus, the following results of an embodiment shown below were obtained. The simulated conditions were set as follows: a power dissipation of the first heat dissipation element  411  is 2 watts (W). A power dissipation of a memory of the portable device  40  is 1.5 W. A power dissipation of the second heat dissipation element  412  is 0.6 W. The fan  30  has a dimension of 92 millimeters (mm)×92 mm×25 mm (length×width×height). A maximum air flow rate of the fan  30  is 35.32 cubic feet per minute (cfm). A rated speed of the fan  30  is 2000 revolutions per minute (rpm). A maximum static pressure of the fan  30  is 0.084 inch-H 2 O. 
         [0021]    The simulation according to the set conditions shows that when using the heat dissipation apparatus of the disclosure, a maximum temperature of the cover plate  42  of the portable device  40  is 45 degrees Celsius, a maximum temperature of the first heat dissipation element  411  is 46 degrees Celsius, a maximum temperature of the memory is 45.3 degrees Celsius, and a maximum temperature of the second heat dissipation element  412  is 48.2 degrees Celsius. In contrast, when using another heat dissipation apparatus, the back of the portable device  40  has a maximum temperature of 45.9 degrees Celsius, the first heat dissipation element  411  has a maximum temperature of 100.4 degrees Celsius, the memory has a maximum temperature of 100.7 degrees Celsius, and the second heat dissipation element  412  has a maximum temperature of 101.7 degrees Celsius. As can be seen, when using the heat dissipation apparatus of the disclosure, the maximum temperature of the portable device  40  is largely decreased, and heat dissipation efficiency is improved. 
         [0022]    Even though numerous characteristics and advantages of the present 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 the matters of shape, size, and the 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.