Abstract:
A fixing assembly includes a main body, a fixing member, and a limiting member secured to the main body. The limiting member angles with the main body to form a limited but resiliently deformable space for mounting of the fixing member, but then restores to hold the fixing member captive and avoid the displacement or loss of the fixing member at any time. A heat sink using the fixing assembly is also provided.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The present disclosure relates to fixing assemblies, and more particularly, to a fixing assembly for fixing heat sinks. 
         [0003]    2. Description of Related Art 
         [0004]    Referring to  FIG. 6 , a heat sink (not shown) is secured to a housing (not shown) by an assembly  400 . The assembly  400  includes a fixing plate  410  fixed to the heat sink, a bolt  420  for securing the fixing plate  410  to the housing, and an elastic throttling member  430 . The fixing plate  410  defines a though hole  412  having a diameter R 1  for mounting the bolt  420 . The bolt  420  includes a head portion  422 , a connecting portion  424  extending from the head portion  422 , and a threaded shank  426  extending from an end of the connecting portion  424  away from the head portion  422 . The diameter of the head portion  422  is greater than the diameter R 1  of the through hole  420 . The diameter of the connecting portion  424  is less than the diameter R 1  of the through hole  420 . The diameter of the threaded shank  426  is greater than the diameter of the connecting portion  424 , but is less than the diameter R 1  of the through hole  420  to allow insertion of the bolt  420 . The elastic throttling member  430  is substantially O-shaped or C shaped and defines a round hole  432 . The outer diameter of the elastic throttling member  430  is greater than the diameter R 1  of the through hole  420 , and the inner diameter R 2  of the throttling member  430  is greater than the diameter of the connecting portion  424 , but is less than the diameter of the threaded shank  426 . However, to mount the bolt  420  to the fixing plate  410 , the bolt  420  is first inserted into the through hole  422 , then, the throttling member  430  is manually forced over the threaded shank  426  to keep the bolt  420  in position on the fixing plate  410 , which requires intricate and forceful assembling of the bolt  420 . Repeated mounting and demounting of the bolt  410  also cause deterioration in the function of the elastic throttling member  430 . 
         [0005]    Therefore, there is room 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 a perspective view of a heat sink including a fixing assembly in accordance with an embodiment. 
           [0008]      FIG. 2  is a disassembled view of the fixing assembly in  FIG. 1 ; the fixing assembly includes a fixing member. 
           [0009]      FIG. 3  is an assembled view of the fixing assembly in  FIG. 2 . 
           [0010]      FIG. 4  is a cross-sectional view taken along line IV-IV in  FIG. 4 . 
           [0011]      FIG. 5  is a view showing the fixing member in  FIG. 3  being mounted. 
           [0012]      FIG. 6  illustrates a perspective view of a fixing assembly of related art. 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    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.” 
         [0014]    Referring to  FIG. 1 , a heat sink  100  in accordance with an embodiment is shown. The heat sink  100  includes a heat-dissipating module  10 , and a plurality of fixing assemblies  20  for fixing the head-dissipating module  10  to a base (not shown). 
         [0015]    Referring to  FIG. 2 , each fixing assembly  20  includes a main body  210 , a fixing member  220 , and a limiting member  230 . The main body  210  is fixed to the heat-dissipating module  10 . An end of the main body  220  away from the heat-dissipating module  10  defines a through slot  212 . The through slot  212  has a length D 1  in a longitudinal direction of the main body  210 , and a width D 2  less than the length D 1 . The main body  210  in the embodiment is made of metal having high thermal conduction, to provide high heat dissipation capability. 
         [0016]    The fixing member  220  is mounted to main body  210  by being inserted through the through slot  212 , and is adapted to fix the main body  210  to the base. The fixing member  220  in the embodiment is a screw or bolt. The fixing member  220  includes a head portion  222  and a threaded shank  224  fixed to the head portion  222 . The diameter of the head portion  222  is greater than the length D 1  of the through slot  212 . The diameter of the threaded shank  224  is slightly less than the width D 2  of the through slot  212 , whereby the threaded shank  224  is fitted in the through slot  212  in a direction perpendicular to the longitudinal direction of the main body  210 . The diameter of the threaded shank  224  is greater than the length D 1  of the though hole  212 , to allow slanted or canted entry of the fixing member  210 . 
         [0017]    Also referring to  FIG. 3 , the limiting member  230  is made of non-rigid and resilient material. The limiting member  230  is secured to the main body  210  and is arranged at one side of the through slot  212 . The limiting member  230  keeps the fixing member  220  always captive after the fixing member  220  is mounted to the main body  210 . The limiting member  230  in the embodiment is integral and bent from an end of the main body  210  away from the head-dissipating module  10 , and is further slanted toward the head-dissipating module  10 . The limiting member  230  makes an angle with the main body  210 , to form a limiting space  234 . After the fixing member  220  is mounted to the main body  210 , the head portion  222  is held captive, prevented from being displaced or falling off. The projection of a distal end  231  to the main body  210  is vertically above the longitudinal direction of the through slot  212 . The distal end  231  is recessed to form a substantially V-shaped recess  232  for facilitating the mounting of the fixing member  220  to the through slot  212 . The width of the recess  232  gradually reduces inwards from the distal end  231 . 
         [0018]    Referring to  FIG. 5 , in assembly, the shank  224  of the fixing member  220  is slantingly inserted into the through slot  212 , and a portion of the head portion  222  is received in the recess  232 . At this time, the limiting member  230  is in an original state to prevent the fixing member  220  from moving toward the main body  210 . An external force F is exerted to the head portion  222 , to force the head portion  222  to slide along the recess  232  toward the main body  210 . At this time, the head portion  222  abuts and presses against the limiting member  230 , and the limiting member  230  gives way to make room for allowing the fixing member  220  to be mounted to the main body  210 . Referring also to  FIGS. 3 and 4 , after the fixing member  220  is mounted to the main body  210 , the limiting member  230  restores to its original shape to limit the head portion  222  in the limiting space  234 . As a result, the limiting member  220  is prevented from being displaced or falling off. 
         [0019]    In the embodiment, when the head portion  222  is mounted to the main body  210  and the stopping portions  232  restores to its original shape, the shank  224  abuts an edge of the through slot  212  away from the limiting member  230 , opposite surfaces of an end of the head portion  222  abut the main body  210  and the limiting member  230  simultaneously, whereby movement of the limiting member  220  is tightly limited. 
         [0020]    Although information as to, and advantages of, the present embodiments have been set forth in the foregoing description, together with details of the structures and functions of the present embodiments, the disclosure is illustrative only; and changes may be made in detail, especially in the matters of shape, size, and arrangement of parts within the principles of the present embodiments to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.