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[0001]    This application claims the priority benefit of Taiwan patent application number 101213322, filed on Jul. 10, 2012. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to shell member mounting technology and more particularly, to an outer shell member positioning device, which comprises a mounting base member mounted at an outer shell member, a bracket pivoted to the mounting base member and engageable into a locating hole of an inner shell member to stop the inner shell member inside the outer shell member in place, a sliding hook member slidably mounted in one end of the bracket and hookable in a retaining hole of the mounting base member to hold the bracket in engagement with the inner shell member, and a locking device mounted in the bracket for locking the sliding hook member. 
         [0004]    2. Description of the Related Art 
         [0005]    As the coming of the information era, various electronic products have entered our life. With the continuous development of innovation technology, electronic hardware equipments are created having versatile functions for multipurpose applications. Most electronic products use a computer to control or execute the operation. In consequence, computer plays an important role in many different fields. In order to enhance the operating speed, a computer server or industrial computer server may be expanded to provide a large number of hard disk drives, multimedia players, DVD-RW drivers, and other peripheral apparatuses. 
         [0006]    Further, an industrial computer server has multiple racks mounted in the server case thereof to hold motherboards, hard disk drives, fan modules, power supply device and many other component parts. To facilitate maintenance and replacement of component parts, the server cases or outer shell members of regular computer servers are commonly made detachable. According to conventional techniques, a server case or outer shell member of a computer server or electronic equipment has slidable hook members provided at two opposite lateral sides thereof for hooking in the internal racks or inner shell members of the server or electronic equipment. The use of sliding hook members facilitates mounting and dismounting of the server case or outer shell member. However, this sliding hook design has low stability. The sliding hook members can be forced out of the hooked position accidentally during delivery of the server or electronic equipment. Further, due to lack of anti-theft measures, an evil person can easily open the server case or outer shell member of the server or electronic equipment to steal the internal electronic component parts or storage data of the server or electronic equipment. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention has been accomplished under the circumstances in view. It is therefore the main object of the present invention to provide an outer shell member positioning device, which comprises a mounting base member, which is mounted at an outer shell member and which comprises two pivot holders located at one end thereof and holding a pivot pin therebetween and a retaining hole located at an opposite end thereof, a bracket, which comprises two constraint bars obliquely disposed at one end there and pivotally coupled to the pivot pin of the mounting base member for engaging into a locating hole in an inner shell member to secure the outer shell member to the inner shell member and box track disposed at an opposite end thereof, a spring-loaded sliding hook member, which comprises two forwardly extending first hook bars slidably hooked in respective sliding slots in two opposite lateral sides of the box track and a downwardly extending second hook bar for hooking in the retaining hole of the mounting base member to hold the bracket in an accommodation open chamber inside the mounting base member, and a locking device mounted in the bracket for locking the sliding hook member in the hooked position to provide an anti-theft effect. 
         [0008]    According to another aspect of the present invention, when the locking device is rotated with the key to move a locking latch thereof from the locking position to the unlocking position, the sliding hook member is released from the constraint of the locking latch and can be moved in the box track to compress the loaded spring thereof and to disengage its second hook bar from the retaining hole of the mounting base member, allowing the bracket to be turned about the pivot pin to the outside of the accommodation open chamber of the mounting base member to release the inner shell member from the constraint of the constraint bars of the bracket. At this time, the outer shell member can be removed from the inner shell member. Thus, the outer shell member positioning device has a high level of structural stability and facilitates operation. 
         [0009]    According to still another aspect of the present invention, when the outer shell member is mounted to the inner shell member, the user simply needs to bias the bracket toward the inside of the accommodation open chamber of the mounting base member to force the constraint bars into engagement with the locating hole of the inner shell member. At this time, the second hook bar of the sliding hook member will be automatically forced into engagement with the retaining hole of the mounting base member to secure the bracket positively in position, and the constraint bars of the bracket are prohibited from being forced out of the locating hole of the inner shell member by a shearing force as the outer shell member is being pulled accidentally by an external force. 
         [0010]    According to still another aspect of the present invention, when the locking device is rotated to the locking position with the key, the locking latch of the locking device is stopped against the base plate of the sliding hook member to prohibit movement of the sliding hook member toward the inside of the box track of the bracket, keeping the second hook bar of the sliding hook member in positive engagement with the retaining hole of the mounting base member, assuring a high level of security. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is an oblique top elevational view of an outer shell member positioning device in accordance with the present invention. 
           [0012]      FIG. 2  is an exploded view of the outer shell member positioning device in accordance with the present invention. 
           [0013]      FIG. 3  corresponds to  FIG. 2  when viewed from another angle. 
           [0014]      FIG. 4  is a sectional side view of the outer shell member positioning device in accordance with the present invention. 
           [0015]      FIG. 5  is a schematic sectional applied view of the present invention, illustrating the outer shell member positioning device mounted in an outer shell member around an inner shell member. 
           [0016]      FIG. 6  is a schematic top view of the present invention, illustrating the locking device rotated from the locking position to the unlocking position. 
           [0017]      FIG. 7  is a schematic sectional side view, illustrating the outer shell member positioning device mounted in an outer shell member around an inner shell and kept in the locking position with the constraint bars of the bracket engaged in the locating hole of the inner shell member, 
           [0018]      FIG. 8  corresponds to  FIG. 7 , illustrating he outer shell member positioning device lifted from the outer shell and the inner shell member disengaged from the constraint of the constraint bars of the bracket of the outer shell member positioning device. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0019]    Referring to  FIGS. 1-4 , an outer shell member positioning device in accordance with the present invention is shown. The outer shell member positioning device comprises a mounting base member  1 , a bracket  2 , a sliding hook member  3 , and a locking device  4 . 
         [0020]    The mounting base member  1  defines an elongated accommodation open chamber  10 , an opening  101  cut through a bottom wall thereof and disposed in communication with one end of the accommodation open chamber  10 , pivoting means, for example, two pivot holders  11  downwardly extended from the bottom wall and arranged at two opposite lateral sides of the first opening  101  in a parallel manner and defining therein a respective pivot hole  111 , a pivot pin  112  inserted into the pivot holes  111  of the pivot holders  11 , a torsion spring  113  mounted on the pivot pin  112 , a retaining hole  12  cut through the bottom wall and disposed in communication with an opposite end of the accommodation open chamber  10 , and mounting portions, for example, mounting through holes  13  disposed around the border area thereof. 
         [0021]    The bracket  2  comprises a base panel  21 , two side panels  211  respectively downwardly extended from the bottom wall of the base panel  21  and symmetrically disposed at two opposite lateral sides, two pivot holes  212  respectively located in the side panels  211  near respective rear ends of the side panels  211 , two opposing constraint bars  22  obliquely downwardly extended from the base panel  21  and defining therein a respective axle hole  221  in axial alignment with the pivot holes  212 , a box track  23  formed integral with the bottom wall of the base panel  21  and respective front parts of the side panels  211  remote from the constraint bars  22 , a sliding space  20  defined in the box track  23 , a bottom opening  201  cut through a bottom wall of the box track  23  in communication with the sliding space  20 , two elongated sliding slots  231  respectively formed in two opposite lateral sides of the box track  23 , a positioning hole  24  vertically cut through the base panel  21  in communication with the sliding space  20  and defining therein two stop edges  2411  and a circularly arched sliding way  241  between the two stop edges  2411 , a stub tube  242  perpendicularly extended from the bottom wall of the base panel  21  around the positioning hole  24  and suspending in the sliding space  20 , and a spring member, for example, coiled spring  25  mounted around the stub tube  242 . 
         [0022]    Further, the constraint bars  22  can be formed integral with the base panel  21  by insert molding. Alternatively, the constraint bars  22  can be separately made and then fastened to the base panel  21  by means of a plug joint, or any of a variety of known fastening techniques. 
         [0023]    The sliding hook member  3  comprises a base plate  31 , two first hook bars  32  respectively and forwardly extended from two opposite lateral sides of the base plate  31  in a horizontal direction and respectively terminating in a respective hooked tip  321 , and a second hook bar  33  downwardly extended from a front side of the base plate  31  between the first hook bar  32  and terminating in a hooked tip  331 . Thus, the first hook bars  32  and the second hook bar  33  are arranged at right angle. 
         [0024]    The locking device  4  comprises a lock cylinder  41  defining a keyway  43  on a top side thereof, a stop block  411  at the periphery thereof near the top side and a locating shank  412  at a bottom side thereof, and a locking latch  42  that defines a mounting hole  421  at one end thereof that is fastened to the locating shank  412 . 
         [0025]    When assembling the outer shell member positioning device, insert the pivot pin  112  through the pivot holders  11  of the mounting base member  1 , the pivot holes  212  of the bracket  2  and the torsion spring  113  to pivotally couple the bracket  2  to the mounting base member  1  and to have two opposite ends of the torsion spring  113  be respectively stopped against one constraint bar  22  of the bracket  2  and the bottom wall of the accommodation open chamber  10  of the mounting base member  1 . At this time, the user can turn the bracket  2  about the pivot pin  11  to move the bracket  2  out of the accommodation open chamber  10  of the mounting base member  1 . When the user releases the hand from the bracket  2  at this time, the elastic potential energy stored within the torsion spring  113  will immediately turn the bracket  2  back to its former position where the bracket  2  is tilted at angle relative to the accommodation open chamber  10  of the mounting base member  1  about the pivot pin  112 . 
         [0026]    Thereafter, insert the sliding hook member  3  into the sliding space  20  in the box track  23  of the bracket  2 . At this time, the two first hook bars  32  will be squeezed inward by two opposite lateral sidewalls of the box track  23 , i.e., the side panels  211  of the bracket  2 , enabling the hooked tips  321  of the first hook bars  32  to be respectively moved into the two elongated sliding slots  231  of the box track  23  subject to the elastic properties of the material of the first hook bars  32 . Subject to coupling between the hooked tips  321  of the first hook bars  32  and the two elongated sliding slots  231  of the box track  23 , the sliding hook member  3  is slidably secured to the box track  23  of the bracket  2  and prohibited from falling out of the bracket  2 . Further, after the bracket  2  and the sliding hook member  3  are received in the accommodation open chamber  10  of the mounting base member  1 , the assembly exhibits low profile characteristics. 
         [0027]    Thereafter, insert the lock cylinder  41  of the locking device  4  through the positioning hole  24  of the bracket  2  and the stub tube  242  to position the stop block  411  in the circularly arched sliding way  241  between the two stop edges  2411  in the positioning hole  24 , and then mount the coiled spring  25  around the stub tube  242  to let two opposite ends of the coiled spring  25  be respectively stopped against the front side of the base plate  31  of the sliding hook member  3  and an inside wall of the box track  23  in the sliding space  20 , and then fasten the mounting hole  421  of the locking latch  42  to the locating shank  412  of the lock cylinder  41  to let the locking latch  42  be rotatably stopped at the bottom side of the stub tube  242 . 
         [0028]    Referring to  FIGS. 5-8 , the outer shell member positioning device is adapted for mounting at an outer shell member  5  (for example, a server cabinet or computer housing) to secure an inner shell member  6  (for example, a server rack or mobile device case) that is put inside the outer shell member. During installation, affix the mounting through holes  13  of the mounting base member  1  of the outer shell member positioning device to the outer shell member  5  around an opening  51  in the outer shell member  5  using bolts, screws, rivets, or a welding technique, and then mount the inner shell member  6  in the outer shell member  5  for enabling the inner shell member  6  to be locked to the outer shell member  5  by the outer shell member positioning device. 
         [0029]    During application of the present invention, insert a tool or key into the keyway  43 , and then rotate the lock cylinder  41  of the locking device  4  through 90-degrees to move the stop block  411  in the circularly arched sliding way  241  from one stop edge  2411  in the positioning hole  24  to the other stop edge  2411 , shifting the locking latch  42  from a locking position where the locking latch  42  is equally spaced between the two first hook bars  32  and stopped against the front side of the base plate  31  of the sliding hook member  3  to an unlocking position where the locking latch  42  extends in a direction perpendicular to the sliding direction of the sliding hook member  3  in the box track  23 . Thereafter, push the base plate  31  of the sliding hook member  3  forward to move the two first hook bars  32  along the elongated sliding slots  231  of the box track  23  and to compress the coiled spring  25 , and simultaneously to disengage the hooked tip  331  of the second hook bar  33  from the retaining hole  12  of the mounting base member  1 , and then bias the sliding hook member  3  to turn the bracket  2  about the pivot pin  112  in direction away from the accommodation open chamber  10 , moving the constraint bars  22  of the bracket  2  from a front side of the opening  101  of the mounting base member  1  to an opposite rear side of the opening  101  where the constraint bars  22  are released from the constraint of a locating hole  61  in the inner shell member  6 . At this time, the outer shell member  5  is unlocked from the inner shell member  6  and can be separated from the inner shell member  6 . Thus, it is convenient to dismount the outer shell member  5  from the inner shell member  6  with less effort. 
         [0030]    When wishing to fasten the outer shell member  5  to the inner shell member  6 , turn the bracket  2  about the pivot pin  112  in the reversed direction toward the inside of the accommodation open chamber  10  of the mounting base member  1  to let two opposite side edges  213  of the mounting base member  1  be stopped at the top wall of the mounting base member  1  around the accommodation open chamber  10 . During movement of the bracket  2  toward the inside of the accommodation open chamber  10  of the mounting base member  1 , the hooked tip  331  of the second hook bar  33  of the sliding hook member  3  is forced by the inside wall of the mounting base member  1  to move forward and then into the retaining hole  12 . After hooking of the hooked tip  331  of the second hook bar  33  on the peripheral edge of the retaining hole  12 , the constraint bars  22  of the bracket  2  are stopped against the peripheral edge of the locating hole  61  of the inner shell member  6  to prohibit pivoting motion between the bracket  2  and the mounting base member  1 . Subject to engagement between the hooked tip  331  of the second hook bar  33  and the peripheral edge of the retaining hole  12 , the constraint bars  22  of the bracket  2  are prohibited from being forced out of the locating hole  61  of the inner shell member  6  by a shearing force as the outer shell member  5  is being pulled accidentally by an external force. 
         [0031]    Thereafter, the user can lock the outer shell member  5  to the inner shell member  6  by: rotating the lock cylinder  41  of the locking device  4  in the reversed direction through 90-degrees to move the locking latch  42  from the unlocking position to the locking position where the locking latch  42  is equally spaced between the two first hook bars  32  and stopped against the front side of the base plate  31  of the sliding hook member  3 . At this time, the hooked tip  331  of the second hook bar  33  is firmly held in engagement with the peripheral edge of the retaining hole  12 . Thus, the outer shell member  5  is locked to the inner shell member  6 . 
         [0032]    Although a particular embodiment of the invention has been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.

Summary:
An outer shell member positioning device includes a mounting base member mounted at an outer shell member, a bracket pivotally coupled to the mounting base member and biasable between a first position where constraint bars of the bracket are engaged in a locating hole of an inner shell member to stop the inner shell member in place and a second position where the inner shell member is released from the constraint of the constraint bars and movable out of the outer shell member, a sliding hook member mounted in one end of the bracket and hookable to the mounting base member to secure the bracket in the first position, and a locking device mounted in the bracket and operable to lock the sliding hook member to the mounting base member.