Abstract:
A fixing device for fixing a first element to a second element is provided. The fixing device includes a post, at least one latching member and an operating member. The post includes a head portion and an end portion. The head portion has a biasing member for generating a compressive force. The end portion defines a chamber with an opening portion defined on a sidewall of the chamber. The at least one latching member is disposed within the chamber. Each latching member has a hook portion extending out laterally. The hook portion is disposed within the opening portion and slides into and out of the chamber through the opening portion. The operating member drives the hook portion to slide into and out of the chamber.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The present disclosure relates to fixing devices, and particularly to a fixing device for securing a first element to a second element. 
         [0003]    2. Description of Related Art 
         [0004]    A number of conventional fasteners, such as heat sink fasteners, are used to attach a first element to a second element. The fasteners extend through clearance holes in the first and second elements, and are constructed to exert a spring force that presses the first element against the second element. The fasteners that are presently used to fasten the first element to the second element are relatively difficult to assemble. Therefore, there is room for improvement in the art. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]    The components of the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of a fixing device. Moreover, in the drawings, like reference numerals designate corresponding parts throughout several views. 
           [0006]      FIG. 1  is an isometric view of a fixing device in accordance with an exemplary embodiment. 
           [0007]      FIG. 2  is an exploded, perspective view of the fixing device of  FIG. 1 . 
           [0008]      FIG. 3  is another isometric view of the fixing device of  FIG. 1 , showing the fixing device in a contracted state. 
           [0009]      FIG. 4  is a cross-sectional view of the fixing device of  FIG. 3 , taken along line IV-IV. 
           [0010]      FIG. 5  is a cross-sectional view taken along line V-V of  FIG. 3 . 
           [0011]      FIG. 6  is a schematic view showing the fixing device employed to fixing a first element to a second element. 
           [0012]      FIG. 7  is another isometric view of the fixing device of  FIG. 1 , showing the fixing device in an elongated state. 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    Referring to  FIGS. 1-2 , an embodiment of a fixing device  100  is illustrated. The fixing device  100  is employed to secure a first element, such as a heat sink, to a second element such as a main board of a computer (see  FIG. 6 ). The fixing device  100  includes an operating member  10 , a post  60 , and a pair of latching members  40 . The post  60  defines a longitudinal receiving space therein. The receiving space includes a first receiving space  212 , a second receiving space  312  and a third receiving space  322  (see  FIG. 4 ). The post  60  includes a first tube  20  and a second tube  30  partially and coaxially nested in the first tube  20 . The operating member  10  is capable of rotating within the receiving space around its own axis. The latching members  40  can move with respect to the second tube  30 , thus the latching members  40  are capable of selectively extending out of and being received in the second tube  30 . The operating member  10  is further moveably connected to the latching members  40  to drive the latching members  40  to extend out of and be received in the second tube  30 . 
         [0014]    The operating member  10  includes a knob  110 , two rods  120 , and a connecting member  130  connecting the knob  110  with the rods  120 . The knob  110  includes a stopper plate  112 . In this embodiment, the stopper plate  112  is substantially circular. The connecting member  130  is a cylinder. One end of the connecting member  130  is attached to the stopper plate  112 . The diameter of the connecting member  130  is less than that of the stopper plate  112 . The rods  120  extend longitudinally from an opposite end of the connecting member  130 , and are symmetrically relative to an axis A of the connecting member  130 . A block  140  further protrudes from the sidewall of the connecting member  130  adjacent to the knob  110 . 
         [0015]    The first tube  20  includes a main body  210 , a slidable element  220  slidably sleeves on the main body  210 , and elastic elements  230  connecting the main body  210  to the slidable element  220 . The slidable element  220  and the elastic elements  230  are considered to be a biasing member  211 . When the fixing device  100  is used to fix the first element and the second element, the biasing member  211  is used to generate compressive force to compress the first element and the second element against the latching members  40 . 
         [0016]    In this embodiment, the main body  210  is substantially cylindrical. The main body  210  defines the first receiving space  212  extending along an axis B of the main body  210  to receive the connecting member  130 . The diameter of the first receiving space  212  is greater than that of the connecting member  130 , but less than that of the stopper plate  112 , thus the connecting member  130  can be rotated in the first receiving space  212 , and the stopper plate  112  can be operable to rotate with the connecting member  130 . 
         [0017]    The main body  210  further defines a pair of openings  214  (see  FIG. 1 ) symmetrically arranged relative to the axis B and communicating with the first receiving space  212 . The openings  214  are adjacent to an end of the main body  210  away from the knob  110 . In this embodiment, each opening  214  is substantially rectangular, and includes a first sidewall  2140  and a second sidewall  2142  opposite to the first sidewall  2140 . Hereinafter, in order to specifically illustrate the present disclosure, the openings  214  are respectively referred to a first opening and a second opening. The first sidewall  2140  of the first opening and the second sidewall  2142  of the second opening are symmetrically arranged relative to the axis B, and the second sidewall  2142  of the first opening and the first sidewall  2140  of the second opening are symmetrically arranged relative to the axis B. Two columns of projections  216  respectively protrude from the first sidewall  2140  of the first opening and the second sidewall  2142  of the second opening. Two adjacent projections  216  in each column are spaced by the same distance to form a first latching slot  2162 . 
         [0018]    A pair of sliding slots  218  is respectively formed in the first opening and the second opening. The projections  216  on the first sidewall  2140  of the first opening and the second sidewall  2142  of the first opening are spaced by a distance to form one of the sliding slots  218 , and the projections  216  on the second sidewall  2142  of the second opening and the first sidewall  2140  of the second opening are spaced by a distance to form another sliding slot  218 . 
         [0019]    A groove  242  is further formed in the sidewall of the first receiving space  212  to receive the block  140 . In this embodiment, the groove  242  is substantially annular. The block  140  can slide in the groove  242  to avoid the operating member  10  separating from the first receiving space  212 . 
         [0020]    In this embodiment, the slidable element  220  is substantially annular. The inner diameter of the slidable element  220  is slightly greater than the diameter of the main body  210 , thus the slidable element  220  can sleeve on the main body  210 . The number of the elastic elements  230  is four. One end of each elastic element  230  is attached to the end of the main body  210  adjacent to the knob  110 , and an opposite end is attached to the slidable element  220 , thus the slidable element  220  can slide along the main body  210  under the restoring force of the elastic elements  230 . The elastic elements  230  are symmetrically arranged relative to the axis B. The number of the elastic elements  230  can vary according to user&#39;s requirements. 
         [0021]    The second tube  30  includes a larger barrel  310  and a smaller barrel  320  connected to and coaxial to the larger barrel  310 . The diameter of the larger barrel  310  is greater than that of the smaller barrel  320 , such that a shoulder  330  is formed in a connecting position of the larger barrel  310  and the smaller barrel  320 . The diameter of the larger barrel  310  is substantially equal to that of the main body  210 . The diameter of the smaller barrel  320  is less than that of the first receiving space  212 , and the smaller barrel  320  is rotatably received in the first receiving space  212 , whereby the second tube  30  partially and coaxially nested in the first tube  20 . 
         [0022]    Referring to  FIGS. 3-4 , the larger barrel  310  defines the second receiving space  312 , and the smaller barrel  320  defines the third receiving space  322  coaxial to and communicating with the second receiving space  312 . The diameter of the second receiving space  312  can be the same as or different from that of the third receiving space  322 . The diameter of the third receiving space  322  is slightly greater than that of the connecting member  130 , such that the connecting member  130  can be received in the third receiving space  322 . The larger barrel  310  defines a pair of guide holes  314  symmetrically arranged relative to an axis C of the larger barrel  310  and away from the smaller barrel  320 . 
         [0023]    Two columns of protrusions  324  (see  FIG. 2 ) protrude from the smaller barrel  320  and are symmetrically about the axis C and away from the larger barrel  310 . In this embodiment, the number of the protrusions  324  in each column is three. Two adjacent protrusions  324  in each column are spaced the same distance apart to form a second latching slot  326 . The height of each protrusion  324  is slightly less than or equal to the depth of each first latching slot  2162 . And the depth of each projection  216  is slightly less than or equal to the depth of each second latching slot  326 , such that the protrusions  324  can engage the projections  216  to secure the second tube  30  to the first tube  20 . The distance between the free end of each protrusion  324  in one column and the free end of one substantially parallel protrusion  324  in another column is substantially equal to or slightly less than the diameter of the main body  210 . Such that the protrusions  324  do not extend out of the openings  214 , and the slidable element  220  can slide along the main body  210 . 
         [0024]    Referring to  FIG. 5 , each latching member  40  is substantially L-shaped. Each latching member  40  includes a hook portion  410  ( FIG. 2 ) and two plates  420  extending upwardly from the hook portion  410  with an interval  422  defined by the two plates  420 . Each hook  410  can be received in one guide hole  314 . The interval  422  is used to slidably receive one rod  120 . Each interval  422  includes two opposite distal ends  425  and a middle portion  424  arranged between the distal ends  425 . 
         [0025]    The fixing device  100  further includes a base  50  ( FIG. 4 ) secured to the end of the larger barrel  310  away from the smaller barrel  320 . The base  50  is substantially circular, and the diameter of the base  50  is slightly less than the inner diameter of the larger barrel  310 . A stopper portion  510  ( FIG. 6 ) protrudes from a surface of the base  50 . 
         [0026]    When assembling the fixing device  100 , the latching members  40  are placed in the second receiving space  312  and each hook portion  410  is received in one guide hole  314 . 
         [0027]    The base  50  is attached to the larger barrel  310  to cause the stopper portion  510  to be arranged between the latching members  40 . The first tube  20  is arranged over the smaller barrel  320  to cause the protrusions  324  to engage the projections  216  adjacent to the knob  110 . The connecting member  130  is placed in the first receiving space  212  to cause the block  140  to be received in the groove  242  and cause each rod  120  to be received in corresponding interval  422 . The knob  110  is then rotated to cause each rod  120  to move to one distal end of each interval  422 . At this point, the hook portions  410  are received in the guide holes  314  respectively. 
         [0028]    After assembly, the connecting member  130 , the main body  210 , the smaller barrel  320 , and the larger barrel  310  are coaxial to each other. The elastic elements  230  are in a natural state. The protrusions  324  engage the projections  216  adjacent to the knob  110 . The hook portions  410  are received in the through holes  314 . 
         [0029]      FIG. 6  expresses how to use the fixing device  100  to secure the fan  80  to the main board  90 . The fan  80  defines a number of first through holes  82 , and the main board  90  defines a number of second through holes  92 . Each first through hole  82  and each second through hole  92  can receive the larger barrel  310 . The diameters of each first through hole  82  and each second through hole  92  are less than that of the slidable element  220 . The total of the depth of each first through hole  82  and each second through hole  92  is less than the distance between the slidable element  220  and one guide hole  314 . When the fixing device  100  secures the fan  80  to the main board  90 , the larger barrel  310  is inserted into one first through hole  82  and one second through hole  92  in sequence until the slidable element  220  resists the fan  80 . At this point, the knob  110  is pressed downward to cause the elastic elements  230  to be compressed and cause the larger barrel  310  to move downward until the guide holes  314  are exposed to the second through hole  92 . At this point, the knob  110  is rotated to cause each rod  120  to move from the distal end  425  to the middle portion  424  of each interval  422 . The movement of each of the rods  120  from the distal end  425  to the middle  424  causes the hook portions  410  to extend out of the guide holes  314  and hook the main board  90 . The knob  110  is then released, and the elastic elements  230  rebound to cause the slidable element  220  to press the fan  80 . At this point, the fan  80  and the main board  90  are secured between the hook portions  410  and the slidable element  220 . 
         [0030]    To separate the fan  80  from the main board  90 , the knob  110  is rotated toward an opposite direction to cause each of the rods  120  to move from the middle portion  424  to the distal end  425 . The movement of each of the rods  120  from the middle portion  424  to the distal end  425  causes the hook portions  410  to be received in the guide holes  314 . The knob  110  is then released, and the elastic elements  230  rebound. At this point, the fixing device  100  can be easily pulled out of the second through hole  92  and the first through hole  82 . 
         [0031]    Referring also to  FIG. 7 , if the total of the depth of the first through hole  82  and the second through hole  92  is larger than the total of the height of the main body  210  and the height of the larger barrel  310 . The second tube  30  is rotated to cause the protrusions  324  to disengage from the projections  216  and move into the sliding slots  218 . The second tube  30  is then pulled downward a certain distance until the fixing device  100  is fit to secure the fan  80  to the main board  90 . The second tube  30  is then rotated to cause the protrusions  324  to engage the projections  216  to secure the second tube  30  to the first tube  20 . At this point, the second tube  30  can be employed to secure the fan  80  to the main board  90 . 
         [0032]    With such configuration, the length of the fixing device  100  can be adjusted according to need, thus the fixing device  100  is fit to secure elements having different length through holes. 
         [0033]    Although the present disclosure has been specifically described on the basis of the exemplary embodiment thereof, the disclosure is not to be construed as being limited thereto. Various changes or modifications may be made to the embodiment without departing from the scope and spirit of the disclosure.