Abstract:
A heat sink includes a plurality of first fins and a plurality of second fins. Each first fin and each second fin includes an inner end and an outer end opposite to the inner end, respectively. Each of the second fins is sandwiched between two respective adjacent first fins. The inner end of each of the first fins is engagingly received in the inner end of the previous adjacent first fin, sandwiching the inner end of a corresponding second fin therebetween. The outer end of each of the first fins is engagingly received in the outer end of the previous adjacent second fin, and the outer end of each of the second fins is engagingly received in the outer end of the previous adjacent first fin.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The disclosure relates to heat sinks and, more particularly, to a heat sink for dissipating heat generated by an electronic component. 
         [0003]    2. Description of Related Art 
         [0004]    With the increasing development of computer technology, electronic components such as central processing units (CPUs) of computers are being made to operate at higher operational speeds and to have greater functional capabilities. When an electronic component operates at high speed, it frequently generates large amounts of heat. The heat must be quickly removed from the electronic component to prevent it from becoming unstable or being damaged. Typically, a heat sink is attached to an outer surface of the electronic component to absorb heat from the electronic component. The heat absorbed by the heat sink is then dissipated to ambient air. 
         [0005]    A typical heat sink includes a plurality of fins. Each fin includes a body, and two flanges extending from the body. In particular, the flanges are bent from upper and lower edges of the body, respectively. Each fin is provided with a protrusive connecting portion which extends toward a neighboring fin. A receiving aperture is defined between the body and the connecting portion. The connecting portion of the fin is received in the receiving aperture of the neighboring fin, thereby connecting the fins together. In this way, a desired number of fins can be attached together in sequence to form the heat sink. The flanges of each two neighboring fins provide an interval between the fins to allow airflow through the heat sink. 
         [0006]    Nowadays, most electronic components are following the trend toward miniaturization. In addition, such components are frequently used in compact electronic products. An electronic component installed in a product may have only a very small surrounding space available for heat dissipation. In many cases, it is necessary or desirable to install a heat sink on the electronic component. How to improve the heat-dissipation efficiency of a heat sink that is used in a very small heat-dissipation space is an ongoing problem in the electronics industry. One approach to this problem is to seek to increase the density of the fins per unit area or unit volume of the heat sink. However, for the above-described typical heat sink, this is difficult to achieve. Due to the flanges of each fin and limitations inherent in the technology of manufacturing the fins, the density of the fins is limited. Another approach to improve the heat-dissipation efficiency of a heat sink is to increase the number of fins, thereby increasing the heat dissipation area of the heat sink. However, the increased number of fins increases the volume of the heat sink. 
         [0007]    What is needed, therefore, is a heat sink which can be used in a limited heat-dissipation space and which has a large number of fins. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    Many aspects of the 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 disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
           [0009]      FIG. 1  is an isometric, partly exploded view of a heat sink in accordance with an embodiment of the disclosure. 
           [0010]      FIG. 2  is an enlarged view of parts of the heat sink of  FIG. 1 . 
           [0011]      FIG. 3  is a side view of a first fin of the heat sink of  FIG. 2 . 
           [0012]      FIG. 4  is a side view of a second fin of the heat sink of  FIG. 2 . 
           [0013]      FIG. 5  is a top plan view of the heat sink of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    Referring to  FIG. 1 , a heat sink in accordance with an embodiment of the disclosure is illustrated. The heat sink has a truncated sector-like configuration; or viewed another way, the heat sink has a shape like part of an annulus. The heat sink includes a plurality of first fins  10  and a plurality of second fins  20 . The second fins  20  are alternately arranged with the first fins  10 . That is, each of the second fins  20  is sandwiched between two adjacent first fins  10 . Each of the first fins  10  is spaced from the neighboring second fin  20 . Thereby, a plurality of air passages  30  between the first fins  10  and the second fins  20  is formed. In the present embodiment, the number of first fins  10  is one more than the number of second fins  20 . The first and second fins  10 ,  20  have the same height as each other. Each of the first and second fins  10 ,  20  is oriented along a radius of a circle defined by the shape of the part of the annulus. Each first and second fin  10 ,  20  extends from an inner end of the heat sink to an outer end of the heat sink. In other embodiments, a larger number of the first and second fins  10 ,  20  can be used, such that the first and second fins  10 ,  20  cooperatively form an annular heat sink. 
         [0015]    Also referring to  FIG. 2 , each of the first fins  10  includes a rectangular body  11 , a first latching portion  12  extending perpendicularly from an outer and shorter edge of the body  11 , a wing portion  13  extending perpendicularly from an inner and shorter edge of the body  11 , and two second latching portions  14  extending perpendicularly from upper and lower edges of the body  11  and located near the wing portion  13 . The wing portion  13  is parallel to the first latching portion  12 . The second latching portions  14  are perpendicular to the wing portion  13 . The first and second latching portions  12 ,  14  and the wing portion  13  of each first fin  10  extend towards a previous adjacent second fin  20 . 
         [0016]    The first latching portion  12  includes a rectangular flange  120  and a protrusive T-shaped connecting portion  122  extending towards the previous adjacent second fin  20 . A T-shaped receiving aperture  124  is defined in the first latching portion  12 , and is located adjacent to the outer edge of the body  11 . Also referring to  FIG. 3 , the receiving aperture  124  extends through a folding portion  125  between the body  11  and the flange  120 . Each of the second latching portions  14  includes a rectangular flange  140  and a protrusive T-shaped connecting portion  142  extending towards the previous adjacent second fin  20 . A T-shaped receiving aperture  144  is defined in each second latching portion  14 . The receiving aperture  144  extends through a folding portion  145  between the body  11  and the flange  140 . The wing portions  13  of the first fins  10  are equal in width to the flanges  140  of the second latching portions  14 . The connecting portion  142  of the first fin  10  is approximately equal in size and shape to the receiving aperture  144  of the previous adjacent first fin  10 , so that the connecting portion  142  is received in the receiving aperture  144 . At the same time, the wing portion  13  of the first fin  10  abuts a folding portion  135  between the wing portion  13  and the body  11  of the previous adjacent first fin  10 , thereby providing an interval between inner ends of two adjacent first fins  10 . The first latching portion  12  of the first fin  10  has an extending length toward the previous adjacent second fin  20  larger than that of each second latching portion  14 . 
         [0017]    Each of the second fins  20  includes a rectangular body  21  and a third latching portion  22  extending perpendicularly from an outer and shorter edge of the body  21 . The third latching portion  22  includes a rectangular flange  220  and a protrusive T-shaped connecting portion  222  extending towards the previous adjacent first fin  10 . A T-shaped receiving aperture  224  is defined in the third latching portion  22 , corresponding to the connecting portion  222 . Also referring to  FIG. 4 , the receiving aperture  224  extends through a folding portion  225  between the body  21  and the flange  220 . 
         [0018]    The connecting portion  122  of the first fin  10  is approximately equal in size and shape to the receiving aperture  224  of the previous adjacent second fin  20 , so that the connecting portion  122  is received in the receiving aperture  224 . At the same time, the flange  120  of the first fin  10  abuts the folding portion  225 . The connecting portion  222  of the second fin  20  is approximately equal in size and shape to the receiving aperture  124  of the previous adjacent first fin  10 , so that the connecting portion  222  is received in the receiving aperture  124 . At the same time, the flange  220  abuts the folding portion  125 . 
         [0019]    In this embodiment, the connecting portions  122  of the first fins  10  have the same shape as the connecting portions  222  of the second fins  20 . The flanges  120 ,  220  of the first and second fins  10 ,  20  are equal in width to each other, thereby providing same intervals between outer ends of every two adjacent first and second fins  10 ,  20 . In other embodiments, the connecting portions  122  of the first fins  10  have different shapes from the connecting portions  222  of the second fins  20 , and the flanges  120 ,  220  of the first and second fins  10 ,  20  have different widths from each other, thereby providing different intervals between outer ends of two adjacent first and second fins  10 ,  20 . In this embodiment, the body  21  of each second fin  20  has two corners of an inner end thereof cut away to form two cutouts  23 . Each of the bodies  11 ,  21  of the first and second fins  10 ,  20  defines a semicircular opening  15  at a center of a lower edge thereof, and forms a semicircular flange  16  extending perpendicularly and bordering the opening  15 . The flanges  16  of the first and second fins  10 ,  20  cooperatively form an arc-shape groove for receiving at least part of a heat pipe (not shown) therein. In other embodiments, the bodies  11 ,  21  of the first and second fins  10 ,  20  may omit the openings  15  and the flanges  16 , according to actual needs. 
         [0020]    The first latching portions  12  of the first fins  10  and the third latching portions  22  of the second fins  20  are alternately interlinked with each other to cooperatively form an outer arc-shaped surface. The connecting portion  142  of each of the first fins  10  extends through a corresponding cutout  23  of the previous adjacent second fin  20 , and is received in the receiving aperture  144  of the previous adjacent first fin  10 . The inner end of each of the second fins  20  abuts the wing portion  13  of the two adjacent first fins  10 . Each of the wing portions  13  of the first fins  10  abuts the folding portion  135  of the previous adjacent first fin  10 , thereby cooperatively forming an inner arc-shaped surface. The inner arc-shaped surface can be attached to another element, such as a heat-conducting block, post or pole. The flanges  120 ,  220  of the first and second fins  10 ,  20  each have a width larger than the flanges  140  of the second latching portions  14 . 
         [0021]    The second latching portion  14  of each first fin  10  is linked with the second latching portion  14  of the previous adjacent fin  10 , and the inner end of the intervening second fin  20  is sandwiched between the inner ends of the two adjacent first fins  10 . With the above-described configuration, in a same limited available heat-dissipation space, the heat sink of the present disclosure can incorporate two times as many fins as a heat sink of the related art. Therefore, the heat sink of the present disclosure provides a much larger heat-dissipation area. 
         [0022]    It is to be understood, however, that even though numerous characteristics and advantages of the present embodiments have been set forth in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and 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.