Abstract:
A retaining device ( 1 ) for expansion cards ( 56 ) each having a slot cover ( 60 ) includes a plate ( 18 ) having an expansion card seat ( 24 ), a pair of locking members ( 76 ), a fastener ( 90 ) pivotably attached to the expansion card seat. Two locking members respectively are fixed on the expansion card seat. Each locking member includes a resilient arm ( 80 ) having a locking body ( 81 ). The fastener includes a pressing plate ( 104 ) for pressing the slot covers. Two locking arms ( 112 ) extend from the pressing plate engaging with corresponding locking bodies. The fastener further includes a handle ( 118 ) and two pushing arms ( 120 ). When the handle is pressed downwardly, the pushing arms push the resilient arms to cause the locking bodies to disengage from the locking arms, and the pressing plate can thereupon be released from the slot covers of the expansion cards by operation of the handle.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to retaining devices, and more particularly to a retaining device securely retaining expansion cards in a computer enclosure.  
           [0003]    2. Description of the Related Art  
           [0004]    Personal computer systems typically include a motherboard for mounting at least one microprocessor and other application specific integrated circuits (ASICS) such as memory controllers, input/output (I/O) controllers and the like. Most motherboards have slots for attachment of additional adapter cards to provide additional functions for the computer system. Typical adapter cards include memory cards, sound cards, graphics cards, and the like. If a personal computer is moved to another location or sustains external shock, the attached adapter cards are prone to be loosened or detached from the slots of the motherboard. Accordingly, the adapter cards must be securely retained in position.  
           [0005]    A retaining device to that end is disclosed in U.S. Pat. No. 5,317,483. The retaining device comprises a pressing plate, an end of which is rotatably attached to the rear plate. In assembly, an opposite end of the pressing plate is attached to a rear plate with a screw. The pressing plate presses slot covers of expansion cards, thereby securing the expansion cards to the rear plate. However, the structure of the retaining device is unduly complex, and this reduces efficiency when assembling the expansion cards to the retaining device.  
         SUMMARY OF THE INVENTION  
         [0006]    Accordingly, an object of the present invention is to provide a retaining device which can readily and securely attach expansion cards in a computer enclosure.  
           [0007]    To achieve the above-mentioned object, a retaining device for expansion cards each having a slot cover comprises a plate having an expansion card seat for securing the slot covers thereon, a pair of locking members respectively fixed on the expansion card seat, a fastener pivotably attached to the expansion card seat. The expansion card seat comprises a top plate and two side plates. Each locking member comprises a resilient arm. A locking body is arranged at a distal end of each resilient arm. The fastener comprises a pressing plate for pressing the slot covers against the top plate. Two locking arms respectively extend from two ends of the pressing plate engaging with corresponding locking bodies. The fastener further comprises a handle. A pair of connecting beams interconnects the pressing plate and the handle. A pair of pushing arms extends from the connecting beams. When the handle is pressed downwardly, the pushing arms push the resilient arms to cause the locking bodies to disengage from the locking arms and the pressing plate is released from the slot covers of the expansion cards via operation of the handle.  
           [0008]    Other objects, advantages and novel features of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which: 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    [0009]FIG. 1 is an exploded, isometric view of a retaining device in accordance with a preferred embodiment of the present invention, together with an expansion card and a computer enclosure having a circuit board with an expansion card socket;  
         [0010]    [0010]FIG. 2 is an enlarged view of a fastener of the retaining device of FIG. 1;  
         [0011]    [0011]FIG. 3 is an enlarged view of one locking member of the retaining device of FIG. 1;  
         [0012]    [0012]FIG. 4 is a partly assembled view of FIG. 1;  
         [0013]    [0013]FIG. 5 is a fully assembled view of FIG. 1, showing the fastener in an unlocked position;  
         [0014]    [0014]FIG. 6 is similar to FIG. 5, but showing the fastener in a locked position; and  
         [0015]    [0015]FIG. 7 is an enlarged view of a circled portion VII of FIG. 6. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0016]    Referring to FIG. 1, a retaining device  1  for expansion cards in accordance with the preferred embodiment of the present invention includes a rear plate  18 , an expansion card seat  24 , a pair of locking members  76  fixed on the expansion card seat  24 , and a fastener  90  pivotably attached to the expansion card seat  24 . The retaining device  1  secures respective ends of one or more expansion cards  56  (only one shown) that are connected onto a circuit board  14  attached on a bottom plate  12  of a computer chassis  10 .  
         [0017]    A plurality of bores  16  is defined in the circuit board  14 , for fixing of expansion card sockets  72  (only one shown) onto the circuit board  14 . The rear plate  18  is perpendicularly attached to an end of the bottom plate  12 . A rectangular opening  20  is defined in the rear plate  18 . A plurality of apertures  22  is defined in the rear plate  18 , the apertures  22  surrounding the opening  20 . The expansion card socket  72  has a plurality of pins  74  inserted into corresponding bores  16  of the circuit board  14 .  
         [0018]    The expansion card seat  24  includes a main plate  32 , a top plate  38 , a lower plate  52  and two side plates  26 , all of which cooperatively define a chamber therebetween. Two flanges  28  extend perpendicularly outwardly from rearmost edges of the side plates  26  respectively. A plurality of apertures  30  is defined in the flanges  28 , corresponding to the apertures  22  of the rear plate  18 .  
         [0019]    A plurality of parallel, vertical expansion card slots  34  is defined in the main plate  32 . A column  36  is thereby defined between each two adjacent expansion card slots  34 . A protrusion  40  is formed on the top plate  38  above each column  36 . A pair of sector-shaped pivot tabs  42  extends perpendicularly upwardly from opposite sides of the top plate  38  respectively. A pivot hole  44  is defined in each pivot tab  42 . A window  46  is defined in the top plate  38 . A supporting tab  48  extends upwardly from the top plate  38  at an end of the window  46 . A supporting hole  50  is defined in the supporting tab  48 . A plurality of receiving slots  54  is defined in the lower plate  52  under the expansion card slots  34  respectively. A pair of screw holes  25  is defined in each side plate  26 , for receiving a corresponding pair of screws  88 . A locking protrusion  27  is outwardly formed on each side plate  26  above the screw holes  25 .  
         [0020]    The expansion card  56  comprises a main body  58 , a bottom of the main body  58  being inserted into the expansion card socket  72 . The expansion card  56  has a slot cover  60  perpendicularly attached to a rear edge thereof. The slot cover  60  comprises two spaced securing tabs  64 , each securing tab  64  defining a through hole  66  therein. A pair of screws (not shown) is extended through the through holes  66  and engaged in the main body  58 , thereby attaching the slot cover  60  to the main body  58 . A bearing tab  68  extends perpendicularly rearwardly from a top of the slot cover  60 . A cutout  70  is defined in the bearing tab  68 , corresponding to any one of the protrusions  40  of the expansion card seat  24 .  
         [0021]    Referring to FIG. 3, each locking member  76  comprises a fixing body  78  for being fixed to a respective side plate  26 . A pair of fixing holes  79  is defined in the fixing body  78 , corresponding to the screw holes  25  of the respective side plate  26 . A resilient arm  80  extends upwardly from the fixing body  78 . A locking body  81  extends upwardly from a top of the resilient arm  80 . The locking body  81  comprises an upper retaining protrusion  84 , thereby defining a cavity  85  under the retaining protrusion  84 . A locking notch  86  is defined in an inside of the locking body  81  adjacent the retaining protrusion  84 , corresponding to the locking protrusion  27  of the respective side plate  26 . The locking body  81  further comprises a post  82  extending upwardly from above the locking notch  86 .  
         [0022]    Referring to FIG. 2, the fastener  90  is for being pivotably attached to the pivot tabs  42  of the top plate  38  by a shaft  92 . A narrowed neck portion  96  is defined at an end of the shaft  92 . A spring clip  98  is for being engaged around the neck portion  96 . The fastener  90  comprises an elongate pressing plate  104 , a generally U-shaped handle  118 , and a pair of connecting beams  116  interconnecting the pressing plate  104  and the handle  118 . The pressing plate  104  forms a plurality of aligned sleeves  100  along a rear edge thereof. Each sleeve  100  defines a pivot hole  102  for receiving the shaft  92 . A plurality of aligned breaches  106  is defined in the pressing plate  104 , respectively corresponding to the expansion card slots  34 . A spring tab  108  extends from an edge of the pressing plate  104  at each breach  106 . A plurality of tabs  110  depends from a front edge of the pressing plate  104 . Two locking arms  112  depend from respective opposite sides of the connecting beams  116  near the pressing plate  104 . Each locking arm  112  comprises a hook  114  at a distal end thereof. A pair of pushing arms  120  extends slantwise downwardly from the respective connecting beams  116  toward the locking arms  112 . A pair of fingers  122  depends from opposite sides of the pressing plate  104  respectively. Each finger  122  comprises a triangulated protrusion  124  at a distal end thereof.  
         [0023]    Referring to FIGS. 3-7, in assembly, the expansion card seat  24  is attached to the rear plate  18  by means of a plurality of screws or rivets being extending through the apertures  30 ,  22 . The expansion card socket  72  is attached to the circuit board  14 , with the pins  74  of the expansion card socket  72  being inserted into the corresponding bores  16  of the circuit board  14 . The locking members  76  are attached to the expansion card seat  24 , with the screws  88  being extended through the fixing holes  79  of the locking members  76  to engage in the screw holes  25  of the side plates  26 . The shaft  92  is inserted through the pivot holes  44 , the pivot holes  102  and the supporting hole  50 . The spring clip  98  is engaged around the neck portion  96  of the shaft  92 . The fastener  90  is thus pivotably attached to the expansion card seat  24 .  
         [0024]    Then the fastener  90  is locked to the top plate  38  of the expansion card seat  24  as follows. The expansion card  56  is inserted into the expansion card socket  72 . The inserting portion  62  of the slot cover  60  is inserted into a corresponding receiving slot  54 . The cutout  70  engagingly receives a corresponding protrusion  40  of the top plate  38 . The handle  118  is rotated downwardly. The locking arms  112  abut against the retaining protrusions  84 , and ride over the retaining protrusions  84  until the hooks  114  are engagingly received in the cavities  85 . In this position, the hooks  114  are engaged with undersides of the retaining protrusions  84 , a corresponding spring tab  108  resiliently presses the bearing tab  68  of the expansion card  56 , and a corresponding tab  110  presses the slot cover  60 . Thus the expansion card  56  is securely held in the expansion card socket  72 . The engagements of the hooks  114  in the cavities  85  prevent the fastener  90  from being rotated upwardly by accident.  
         [0025]    In disassembly, the handle  118  is pushed downwardly. The resilient arms  80  of the locking members  76  are moved toward the rear plate  18  by the pushing arms  120 . The locking protrusions  27  of the side plates  26  enter the locking notches  86 , thereby attaching the locking bodies  81  to the side plates  26  while simultaneously displacing the locking bodies  81  outwardly. The hooks  114  are thus freed from the retaining protrusions  84  of the locking bodies  81 . The handle  118  is rotated upwardly, and the triangulated protrusions  124  of the fingers  122  enter respective gaps between the posts  82  of the locking bodies  80  and the side plates  26 . The triangulated protrusions  124  push the posts  82  away from the side plates  26  so that the locking bodies  81  at the locking notches  86  disengage from the locking protrusions  27 , whereupon the resilient arms  80  rebound back to their original positions. The spring tab  108  disengages from the bearing tab  68 , and the tab  110  disengages from the slot cover  60 . The expansion card  56  is then easily removed from the rear plate  18  and the expansion card socket  72 .  
         [0026]    It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, 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 invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.