Abstract:
An exemplary retention assembly ( 30 ) is used to assemble expansion cards ( 20 ) or covers ( 22   b ) to an enclosure ( 24 ). The retention assembly includes a frame ( 36 ) for being fixed to the enclosure and at least one latching holder ( 31 ). Each of the at least one resisting portion of the frame is arranged to one of the at least one guiding rail respectively. The frame includes at least one guiding rail ( 364 ) and at least one resisting portion ( 369 ) disposed corresponding to the at least one guiding rail. The at least one latching holder includes a holding piece ( 322 ) for holding the cover and a resisting portion ( 348 ) configured for engaging with the resisting portion of the frame. Part of the at least one latching holder is deformable to make the resisting portions of the latching holder and the frame disengaging from each other.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention generally relates to retention assemblies, particularly to an expansion card retention assembly for securing expansion cards to an electronic device enclosure. 
         [0003]    2. Discussion of the Related Art 
         [0004]    Referring to  FIG. 5 , this shows a typical retention assembly used for securing expansion cards  10  (for briefness, only one expansion card  10  is shown in  FIG. 5 ) to an electronic device enclosure  13 . The retention assembly includes a catching plate  11 , a plurality of bolts  12 , and a plurality of covers  14 . The electronic device enclosure  13  forms an expansion card platform  130  for mounting the expansion cards  10 . The expansion card platform  130  defines a plurality of vertical expansion slots (not visible). A bulge  132  is formed at a bottom of each expansion slot. The covers  14  are configured for covering the expansion slots. Each of the covers  14  is an elongated piece having a bent top end, and a narrowed bottom end (not labeled) engaging in the corresponding bulge  132 . When one or more expansion cards  10  are fixed to the electronic device enclosure  13 , the catching plate  11  is positioned on the bent top ends of the covers  14 . The catching plate  11  is then fixed on the electronic device enclosure  13  by the bolts  12  being engaged in screw holes defined in the expansion card platform  130 , thereby fastening the covers  14  to the electronic device enclosure  13 . Each expansion card  10  has a mounting portion  102  having a same structure as the cover  14 . Thereby, with the same manners, the expansion cards  10  maybe fastened to the electronic device enclosure  13 . 
         [0005]    In the above retention assembly, the covers  14  and the expansion cards  10  are secured to the electronic device enclosure  13  by using the bolts  12 . However, installing or removing the bolts  12  is unduly time-consuming and laborious. This decreases the efficiency of installation and removal of expansion cards. In addition, a tool for installing or removing the bolts  12  is usually needed. These problems are multiplied in mass production facilities. Furthermore, after a period of time, the bolts  12  may become displaced and no longer be reliably engaged in the screw holes. 
         [0006]    Therefore, a retention assembly which overcomes the above-described shortcomings is desired. 
       SUMMARY 
       [0007]    An exemplary retention assembly is used to receive an expansion card mounted to an cover to an enclosure. The retention assembly includes a frame for being fixed to the enclosure and at least one latching holder. The frame includes at least one guiding rail and at least one resisting portion disposed corresponding to the at least one guiding rail. Each of the at least one resisting portion is arranged to one of the at least one guiding rail respectively. The at least one latching holder includes a holding piece for holding the cover and a resisting portion configured for engaging with the resisting portion of the frame. Part of the at least one latching holder is deformable to disengage the resisting portions of the latching holder and the frame from each other. 
         [0008]    Other advantages and novel features will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the retention assembly. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
           [0010]      FIG. 1  is an isometric view of part of an enclosure, the enclosure having an expansion card retention assembly in accordance with a preferred embodiment of the present invention, and showing the retention assembly fully closed off with a plurality of covers thereof. 
           [0011]      FIG. 2  is an exploded view of the retention assembly of the enclosure of  FIG. 1 . 
           [0012]      FIG. 3  is very similar to  FIG. 1 , but showing a process of removing one of the covers of the retention assembly. 
           [0013]      FIG. 4  is an partially enlarged view of the retention assembly taken of part IV of  FIG. 3 . 
           [0014]      FIG. 5  is an assembled, isometric view of a part of an electronic device enclosure, the enclosure having a conventional expansion card retention assembly. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0015]    Referring to the drawings in detail,  FIG. 1  shows a retention assembly  30  of a preferred embodiment of the present invention. Referring also to  FIG. 2 , the retention assembly  30  is configured to fasten expansion cards  20  (for briefness, only one expansion card  20  is shown in  FIGS. 1 and 2 ) to an enclosure  24 . The retention assembly  30  is also configured to fasten covers  22   b,  each cover  22   b  covering a corresponding slot  242  not occupied by an expansion card. 
         [0016]    For exemplary purposes, only one expansion card  20  will be detailed to clearly describe the preferred embodiment. The expansion card  20  includes a mounting portion  22   a  and a card portion  23 . The mounting portion  22   a  includes an elongated main portion  222  and a fastening portion  224  extending substantially perpendicularly from one end of the elongated main portion  222 . An edge of the fastening portion  224  defines a notch  226 . The mounting portion  22   a  further includes a tab  228  extending from the other end of the elongated main portion  222  opposite to the fastening portion  224 . A width of the tab  228  is smaller than that of the main portion  222 . The card portion  23  is substantially perpendicularly to the main portion  222 . 
         [0017]    Each cover  22   b  has a structure substantially same as the mounting portion  22   a  of the expansion card  20 . Thus, for briefness, the cover  22   b  is not detailed described. 
         [0018]    The enclosure  24  includes an expansion card platform (rack)  244 . The platform  244  has a seating surface  253 , and peripheral walls  255  extending from the seating surface  253 . In the illustrated embodiment, the seating surface  253  is substantially rectangular or square. One peripheral wall  255  defines a first surface  250 , and an opposite peripheral wall  255  defines a second surface  251 . The seating surface  253  defines a plurality of expansion card slots  242 , being elongated and substantially parallel to each other. For exemplary purposes, only one expansion card slot  242  will be detailed to clearly describe the preferred embodiment. The expansion card slot  242  extending from the first surface  250  towards but not reaching the second surface  251 . The platform  244  further forms a plurality of positioning members  246  on the first surface  250 , corresponding to a top of the expansion card slots  242 ; correspondingly, and a plurality of hooking members  248  on the seating surface  253  adjacent to the second surface  251 , corresponding to a bottom of the expansion card slots  242 . Each of the positioning members  246  is configured to be receivable in the notch  226  of the mounting portion  22   a  of the expansion card  20  or the corresponding portion of the cover  22   b,  and each of the hooking members  248  is configured to engagingly receive the tab  228  of the mounting portion  22   a  of the expansion card  20  or the corresponding portion of cover  22   b.    
         [0019]    The retention assembly  30  includes a plurality of movable holders  32 , a plurality of latching clips  34 , and a frame  36 . The number of movable holders  32  and the number of latching clips  34  each correspond to the number of the expansion card slots  242 . That is, one movable holder  32  and one latching clip  34  cooperatively hold one expansion card  20  or one cover  22   b.  In this embodiment, there are five movable holders  32  and five latching clips  34 . 
         [0020]    For exemplary purposes, only one movable holder  32  and one latching clip  34  will be detailed. Each movable holder  32  is substantially L-shaped, and includes a holding piece  322  and a connecting piece  324  substantially perpendicularly connected to the holding piece  322 . Two edges on opposite sides of the connecting piece  324  are bent to form two slide rails  326  correspondingly. At least one protrusion  328  is formed on the connecting piece  324 . In the illustrated embodiment, there are two protrusions  328 , and each protrusion  328  is in the form of an annular collar. 
         [0021]    The latching clip  34  is substantially L-shaped, and includes a hooking piece  342  and a handle  344  substantially perpendicular to the hooking piece  342 . The hooking piece  342  defines at least one hole  346  configured for engagingly receiving the at least one protrusion  328  of the movable holder  32 , thus fixing the movable holder  32  to the latching clip  34 . In the illustrated embodiment, there are two holes  346 . The hooking piece  342  includes a protruding hook  348 , which can be formed by punching. The protruding hook  348  and the handle  344  extend in substantially opposite directions from the hooking piece  342 . The latching clip  34  is elastic. The width of the latching clip  34  corresponds to the distance between the free ends of the slide rails  326  of the movable holder  32 . 
         [0022]    The frame  36  is elongate, and includes a flat sheet  360  defining a plurality of openings  362 . Preferably, the number of the openings  362  corresponds to the number of latching clips  34 . The openings  362  are arranged in a horizontal line. A pair of guiding rails  364  are formed at opposite sides of each of the openings  362 . The guiding rails  364  extend substantially perpendicularly to the horizontal alignment of the openings  362 . Each pair of guiding rails  364  defines a slideway  366  for receiving the slide rails  326  of the movable holder  32  correspondingly, thus allowing the movable holder  32  to slide relative to the frame  36  along the slideway  366 . The flat sheet  360  further defines a plurality of hooking slots  368  adjacent to each of the plurality of openings  362  correspondingly, thereby forming a plurality of latching edges  369 . The latching edges  369  are configured for being latchingly abutting the protruding hooks  348  of the latching clips  34 . The frame  36  is fixed to the enclosure  24 . The width of each opening  362  corresponds to the outer width of the connecting piece  324  of the movable holder  32 . 
         [0023]    Referring also to  FIG. 3 , in assembly, each movable holder  32  and one corresponding latching clip  34  are fixed to each other by inserting the protrusions  328  of the movable holder  32  into the holes  346  of the latching clip  34  and then riveting the protrusions  328  form a latching holder  31 . Alternatively, the movable holder  32  and the latching clip  34  may be fixed by other fastening means such as welding and screwing. The frame  36  is fixed to the enclosure  24  and is positioned corresponding to the platform  244 , with the openings  362  corresponding to the expansion card slots  242 . The latching holder  31  is configured to engage in the slideway  366  along the corresponding guiding rails  364  of the frame  36 . When the holding piece  322  of the movable holder  32  resists the cover  22   b  or the mounting portion  22   a  of the expansion card  20 , the protruding hook  348  of the latching clip  34  is hooked into the corresponding hooking slot  368  and abuts or resists the corresponding latching edge  369 . 
         [0024]    In use, the retention assembly  30  can be considered to have two states, an open state and a closed off state. Referring to  FIG. 1  again, in the closed off state, the covers  22   b  and the expansion cards  20  are installed in the enclosure  24 . For exemplary purposes, one expansion card  20  installed in the enclosure  24  is detailed. The tab  228  of the mounting portion  22   a  of the expansion card  20  is inserted into the corresponding hooking member  248 , and the notch  226  of the mounting portion  22   a  of the expansion card  20  engagingly receives the corresponding positioning member  246 . In the closed off state, the holding piece  322  of the corresponding movable holder  32  abuts or resists the mounting portion  22   a  of the expansion card  20 . The slide rails  326  of the movable holder  32  slidingly engage with the corresponding guiding rails  364  of the frame  36 , and the protruding hook  348  of the corresponding latching clip  34  hooks (latches) in the corresponding hooking slot  368  and abut or resists the latching edge  369  of the frame  36 . 
         [0025]    Referring to  FIG. 3  and  FIG. 4 , to add an expansion card  20  to the enclosure  24 , one corresponding cover  22   b  is removed. The handle  344  of the latching clip  34  is pulled horizontally away from the flat sheet  360 . Thereby, the latching clip  34  deforms, and the protruding hook  348  disengages from the hooking slot  368  of the frame  36 . Then the latching holder  31  can be pulled up, with the movable holder  32  sliding along the guiding rails  364  relative to the frame  36  in a direction parallel to the arrow shown in  FIG. 3  until the latching holder  31  is completely disengaged from the frame  36 . Then the cover  22   b  can be pulled up, with a tab  228  disengaging from the corresponding hooking member  248  and a fastening portion disengaged from the corresponding positioning member  246  of the platform  244 . 
         [0026]    Subsequently, an expansion card  20  can be installed in the enclosure  24  corresponding to the expansion card slot  242  which the cover  22   b  removed from. The steps to install the expansion card  20  are substantially the reverse of the above-described removal steps. That is, the latching holder  31  is slid down so that the movable holder  32  slides along the guiding rails  364  of the frame  36 . In this process, the latching clip  34  deforms until eventually the protruding hook  348  of the latching clip  34  snappingly engages in the hooking slot  368  and abuts or resists the latching edge  369  of the frame  36 . As such, the expansion card slot  242  returns to the closed off state. 
         [0027]    In the retention assembly  30 , each movable holder  32  and one corresponding latching clip  34  hold one cover  22   b  or one expansion card  20 . Therefore when adding or removing an expansion card  20 , only the corresponding latching holder  31  needs to be unlatched or latched, and any other expansion cards  20  already held in the enclosure  24  remain undisturbed firmly in position. 
         [0028]    In an alternative embodiment, the frame  36  may be an integral part of the enclosure  24 . The openings  362  of the frame  36  may be omitted, so long as the frame  36  has the guiding rails  364 . Each latching holder  31  may hold more than one cover  22   b  and/or expansion card  20 , by increasing the width of the movable holder  32 . The hooking slots  368  of the frame  36  may be omitted so long as the frame  36  forms a plurality of abutting or resisting portions that function much like the latching edges  369 . The protruding hook  348  of the latching clip  34  may be replaced by another suitable kind of abutting or resisting portion such as an edge of a slot. 
         [0029]    It is believed that the present embodiments and their advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the examples hereinbefore described merely being preferred or exemplary embodiments of the invention.