Patent Publication Number: US-2007119791-A1

Title: Locking member for locking a card with respect to a shelf

Description:
TECHNICAL FIELD  
      The present invention generally relates to a mobile communication system, and more particularly to a locking member for releasibly locking a card with respect to a shelf upon completing a loading process of the card into the shelf.  
     BACKGROUND ART  
      Conventionally, a rack used for a mobile communication system performs a communication by using a protocol defined for radio link as well as a control station and a mobile station. As shown in  FIG. 1 , the rack  10  houses a number of shelves  20  in such a way that the shelves  20  are positioned on numerous stories of the rack  10 . The shelf  20  accommodates cards connected to external devices based on a multiplexing scheme.  
      As shown in  FIG. 2 , the shelf  20  includes an upper frame  22  having a groove  221  and a lower frame  23  having a groove  231 . The shelf  20  also includes a plurality of guiding members  24  separated from one another at a predetermined interval. The guiding member  24  has a guiding rail  241 .  
      Further, the card  30  includes: a printed circuit board  31  adapted to move along the guiding rail  241 ; a front panel  32  joined to a front end of the printed circuit board  31 ; and ejectors  40 . The ejectors  40  are mounted to an upper portion and a lower portion of the front panel  32  and engaged into the grooves  221 ,  231  of the upper frame and the lower frame  22 ,  23 .  
      The ejector  40  includes: a support member  41  fixed to the end of the front panel  32  for preventing movements of the card  30 ; an engagement member  42  having a protrusion  421  engaged into the groove  221 ; and an unlocking member  43  rotatably attached to the engagement member  42  for releasing a locked state of the front panel  32 .  
      The prior art process for loading the card  30  by using the ejectors  40  will be described hereunder.  
      The front panel  32  is first joined to a front end of the printed circuit board  31 . Then, the ejectors  40  equipped with the unlocking members  43  are fixed to the front panel  32 .  
      The card  30  equipped with the ejectors  40  in the above manner is inserted into the shelf  20  along the guiding rail  241  of the guiding member  24 . Subsequently, a connector (not shown) of the printed circuit board  31  is connected to a socket of the shelf  20 . Next, the protrusions  421  are engaged into the grooves  221 ,  231  by upward and downward rotations of the engagement members  42 . This is so that the card becomes fully loaded in the shelf  20  in order to be accommodated.  
      Meanwhile, dummy cards  30 ′ are mounted on the guiding members  24  that are not equipped with the card  30  having the printed circuit board  31 . Each of the dummy cards  31 ′ includes: a guiding plate  33  that is the same size as the printed circuit board  31 ; the front panel  32 ; and the ejectors  40  which are joined to the guiding plate  33 .  
      However, since the ejector which functions to lock the card with the printed circuit board to the shelf has a number of components and a complex manufacturing process, it increases the manufacturing costs while lowering productivity.  
      Since the dummy cards located in the guiding members that are not loaded with the cards having the printed circuit board also use the ejectors which are expensive for performing the function of the dummy card, the manufacturing costs are further increased.  
     DISCLOSURE OF INVENTION  
      Technical Problem  
      Thus, it is an object of the present invention to provide a card-locking member for locking a card with respect to a shelf by using a resilient force caused by a plate like member upon completing the card loading process into the shelf.  
      Technical Solution  
      In order to achieve the above object, the present invention provides a locking member for locking a card with respect to a shelf having an end with a groove upon completing the card loading process into the shelf. The locking member comprises: a connecting section joined to the card; a resilient section extending from the connecting section and having a resilience; and an engagement section formed at an end of the resilient section and having a shape configured to engage into the groove. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is an exploded perspective view of the prior art communication system.  
       FIG. 2  is a sectional view showing a state in which a card is locked with respect to a shelf by a prior art locking member.  
       FIG. 3  is a perspective view of an inventive locking member for locking a card.  
       FIG. 4  is a sectional view showing a state in which the inventive locking member locks the dummy card with respect to the shelf.  
       FIGS. 5, 6  and  7  illustrate sectional views of the inventive locking member being engaged into the groove of the shelf.  FIGS. 5 and 7  show the locking member before and after the engagement  FIG. 6  illustrates the locking member abutting an end of an upper frame of the shelf. 
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION  
      One embodiment of the present invention is now described in detail with reference to the accompanying drawings. Corresponding reference numerals are designated for components similar to those shown in the prior art section.  
       FIG. 3  shows a perspective view of an inventive locking member for locking the dummy card.  FIG. 4  is a sectional view showing a state in which the inventive locking member locks the dummy card with respect to the shelf.  
      The locking member  60  is a fixing or locking member which locks or fixes the card  30  or the dummy card  30 ′ with respect to the shelf  20 . The term “dummy card” means a card that is to be mounted on the guiding member  24  on which the card with the printed circuit board  31  is not loaded. In this embodiment, the locking member  60  is applied to the dummy card  30 ′. However, the inventive locking member  60  can be applied to the card  30  with the printed circuit board  31 .  
      The locking member  60  is first assembled into the dummy card  30 ′ and then the assembly is slid into the shelf  20  for the loading process. Upon completion of the loading process, the locking members  60  are engaged into the grooves  221 ,  231  of the upper frame and the lower frame  22 ,  23 .  
      The locking member  60  includes a connecting section  61  to be closely contacted on the front panel  32 . This is to allow the locking member to be kept on the dummy card  30 ′. The locking member  60  also includes: a U-shaped resilient section  62  having resilience and extending from the connecting section  61 ; an engagement section  63  extending from the resilient section  62 ; and an extension section  64  extending from the engagement section  63 . The engagement section  63  is formed at an end of the resilient section. It has a shape protruding from the resilient section  62  and the extension section  64  and is engagable into the groove  221  or  231 . For an unloading process of the dummy card  30 ′ the user can depress the extension section  64 . All of the sections  61 ,  62 ,  63  and  64  are formed in one piece. The degree of the resilience of the locking member  60  can be adjusted by varying the thickness of the locking member  60 .  
      The locking operation of the dummy card  30 ′ by the inventive locking member  60  as constructed above will be described hereunder.  
      First, the front panel  32  is assembled with the guiding plate  33  of the dummy card  30 ′. Next, the locking member  60  is fixed on the front panel  32  by clamping the connecting section  61  with the same  32 . A through hole  61   a  of the connecting section  61  and a thread (not shown) can be used for the clamping. Then, as shown in  FIG. 5 , the dummy card  30 ′ equipped with both the front panel  32  and the locking member  60  is slid into the shelf  20 . Subsequently, as shown in  FIG. 6 , when the engagement section  63  abuts an end of the upper frame  22  in the sliding into the shelf  20 , the position of the engagement section  63  is lowered due to the shrinkage of the resilient section  62 . Thereafter, the engagement section  63  advances into the shelf  20  under a pressing force by the end of the upper frame  22 . Next, as shown in  FIG. 7 , when the engagement section  63  meets the groove  221 , the pressing force is removed, while the engagement section  63  is engaged into the groove  221 .  
      Meanwhile, in order to separate the dummy card  30 ′ from the shelf  20 , the user presses the extension section  64 . The pressing force lowers the vertical position of the engagement section  63 , thereby shrinking the resilient section  62 . Then, the engagement section  63  can be disengaged from the groove  221 . In this situation, when the user pulls the front panel  32  of the dummy card  30 ′ out of the shelf  20 , the dummy card  30 ′ exits from the shelf  20  along the guiding rail  241  of the guiding member  24 .  
      The dummy card  30 ′ is loaded into the shelf  20  through the process as described above. In use, the dummy card  30 ′ can be later replaced with the card  30  having the printed circuit board  31 . Of course, the locking member  60  may be applied to the card  30  with the printed circuit board  31 .  
     INDUSTRIAL APPLICABILITY  
      The inventive locking member for locking the cards with respect to the shelf by using the resilient force has a simple configuration, thereby yielding a simple manufacturing process. Accordingly, the manufacturing costs are significantly reduced.