Abstract:
A cross member of a T bar ceiling system is designed to be part of the ceiling grid system and adapted to releasably receive a strip light beneath the cross T member. The strip light provides support flanges beneath the T member for supporting a. ceiling panel edge at the conventional height. With this arrangement the grid system can be installed in the normal manner with these cross T&#39;s at positions where strip lights are to be secured. The strip lights can be installed at a later point in time. Preferably a. push. type releasable connection is used.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention is with respect to strip lighting designed as part of a ceiling grid system, 
       BACKGROUND OF THE INVENTION 
       [0002]    Strip lighting such as LED lighting and other low voltage light sources have been incorporated into suspension systems of a grid network of a ceiling panel suspension system. In one arrangement the strip light assembly is an LED strip light, with the light, housing being an actual cross member of a T bar grid system. With this system strip lighting can be provided at any of the cross members of a ceiling grid system however the strip light is installed as part of the actual grid system. This is in contrast to the well accepted practice of ceiling grid systems being installed by a first group of contractors and lighting associated with the ceiling system is installed by electricians either before the grid system is installed, after the grid system is installed, or as the grid system is being installed. 
         [0003]    By having the strip light part of the actual ceiling grid system, difficulties can be encountered, particularly on large commercial projects where different union greens are represented. In addition, it is desirable to have the ceiling grid system as a single contract separate and apart from the lighting contract. 
         [0004]    It has also been proposed to merely provide strip lighting which is directly suspended below the grid members at a desired position after the grid system is installed. This type of arrangement often requires modification of the panels, and access to the area above the finished ceiling may be more difficult. 
         [0005]    The present invention provides an alternative to these practices and allows the installation of the ceiling grid system to be completed in a manner that strip lighting can be provided at predetermined locations after the grid network has been installed. 
       SUMMARY OF THE INVENTION  
       [0006]    A cross member of a T bar ceiling grid system according to the present invention comprises bayonet type fasteners at opposite ends of the cross component with an elongate bridging member extending between the bayonet fasteners and spaced to an upper side of the bayonet fasteners. The elongate bridging component includes a pair of opposed side walls defining a downwardly opening aligning slot therebetween and a connection head above and joined to the sidewalls. 
         [0007]    In an aspect of the invention, the side walls include longitudinal extending ribs on the exterior surface thereof for engaging and retaining spring clips of a light strip arrangement. 
         [0008]    In a preferred aspect of the invention a bottom edge of the side walls is above a midpoint in height of the bayonet type fasteners. 
         [0009]    In yet a further aspect of the invention the connection head includes a series of heat distribution fins extending outwardly therefrom. Preferably, the elongate bridging member is of an extruded cross section throughout a length thereof. 
         [0010]    In an aspect of the invention, the cross member is used in combination with a strip light adapted to releasably engage and be supported from the cross member. The strip light includes a housing having on a top surface a securing flange extending upwardly and extending in a length of the housing. The securing flange is of a size for edge insertion between the pair of opposed side walls of the cross member. Releasable fastening members secure the strip light to the cross member. 
         [0011]    In an aspect of the invention, the fastening members are releasable spring clips secured to the securing flange and positioned to engage the side walls to secure the strip light to the cross member when the securing flange is inserted between the side walls. Preferably she releasable spring clips are secured on opposite sides of the securing flange and engage securing ribs provided on outside facing surfaces of the side walls. 
         [0012]    In yet a further aspect of the combination, the securing flange is positioned intermediate the length of the housing to generally extend between the bayonet type fasteners such that the bayonet type fasteners are located beyond the ends of the securing flange when the strip light is connected to the cross member. 
         [0013]    In a preferred aspect of the combination, the housing includes a series of ribs extending in the length and provided either end of the housing for receiving and engaging a bottom edge of the bayonet type fasteners when the strip light is supported by the cross member. Preferably, the bayonet type fasteners are partially received in the downwardly aligning slot and secured to the side wails such that the bayonet type fasteners extend outwardly from opposed ends of the elongate bridging member. 
         [0014]    Preferably, the bayonet type fasteners are positioned below the connection head of the bridging member. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    Preferred embodiments of the invention are shown in the drawings, wherein: 
           [0016]      FIG. 1  is a perspective view of a strip light and a T bar supporting member before securement; 
           [0017]      FIG. 2  is an end view of the T bar support member of  FIG. 1 ; 
           [0018]      FIG. 3  is an end view of the strip light of  FIG. 1 ; 
           [0019]      FIG. 4  is a perspective view of the elongate body member of the T bar support member of  FIG. 1 ; 
           [0020]      FIG. 5  is an end view of the elongate body member of  FIG. 4 ; 
           [0021]      FIG. 6  is a perspective view of the strip light and T bar support member in a secured position; 
           [0022]      FIG. 7  is an end view of the structure shown in  FIG. 6 ; 
           [0023]      FIG. 8  is a partial perspective view of the secured strip light and T bar support member; 
           [0024]      FIG. 9  shows details of two opposed spring clips; 
           [0025]      FIG. 10  is a partial perspective view of a grid system showing one T bar support for receiving a strip light; 
           [0026]      FIG. 11  is a partial perspective view of the connect of the one T bar support member to a main T bar member; 
           [0027]      FIGS. 12 and 13  are similar to  FIGS. 10 and 11  and additionally show a strip light about to be secured; 
           [0028]      FIGS. 14 and 15  show the strip light of  FIGS. 12 and 13  secured to the T bar member. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0029]      FIG. 1  shows a strip light assembly  2 , in this case designed for a T bar ceiling paneling system. The strip light assembly is made up of a T bar member  4  shown as a cross T of a T bar suspension system. T bar connectors  6  are provided at opposite ends of the T bar member. The connectors  6  extend downwardly from the raised elongate connecting member  8 . Preferably the raised elongate connecting member  8  is an extruded metal member having a finned thermal transfer head  30  designed to dissipate heat produced by the strip light housing arrangement  16  to the space above the grid system. The strip light housing arrangement  16  includes a series of low voltage light sources spaced in the length of the housing and the strip light is subsequently connected to a low voltage power supply typically mounted above the grid system. 
         [0030]    The strip light housing arrangement  16  includes a light housing  18  of a ‘U’ shape or channel shape that opens in a downward direction. An insert projection  20  is provided on the top surface of the light housing  18  and is centered in the width of the light housing. A series of retaining springs  22  are provided on the insert projection and these spring clips cooperate to releasably attach the raised elongate connecting member  18  of the strip light assembly to the grid system. 
         [0031]      FIG. 2  is an end view of T bar member  4  showing the T bar connectors and the raised elongate connecting member  8 .  FIG. 3  is a cross section of the strip light housing arrangement. 
         [0032]      FIGS. 4 and 5  show additional details of the raised elongate connecting member  8 . The upper most portion of the raised connecting member  8  is defined by the finned thermal transfer head  30  which not only provides structural rigidity to the T bar member but also acts to dissipate heat that has been conducted to this member from the strip light housing arrangement  16 . Below the fins thermal transfer head  30  are two downwardly extending stabilizing arms  32  and  33 . A securing gap  34  is defined between these downwardly extending stabilizing arms as shown in  FIG. 5 . The downwardly extending stabilizing arms  32  and  33  each include outwardly facing upper and lower securing beads  36  and  37 . 
         [0033]    The retaining spring clips  22  releasably interlock with these outwardly facing upper and lower securing beads  35  and  37  when the strip light housing arrangement has been moved into secure engagement with the T bar member  4 .  FIG. 6  illustrates the strip light housing  16  when secured to the T bar member  4 . The sectional view is also shown in  FIG. 7 . 
         [0034]    It can be seen that the insert projection  20  of the strip light housing arrangement  16  is received between the two downwardly extending stabilizing arms  32  and  33 . The retaining spring clips  22  are provided to the exterior of the downwardly extending stabilizing arms and have recesses on the interior surface of the retaining spring clips to interlock with the outwardly facing upper and lower securing beads  36  and  37  of the T bar member  4 . 
         [0035]    The T bar connectors  6  when secured to the T bar member  4 , project downwardly from the raised elongate connecting member. When the strip light housing arrangement  16  is brought into engagement with the T bar member, the T bar connectors  6  align and lock in a receiving slot on the upper surface of the strip light housing arrangement  16  as shown in  FIG. 6 . With this particular cooperation either end of the strip light housing arrangement  16 , the strip light housing arrangement is securely mounted to the raised elongate connecting member  8  due to the insert projection  20  being received in two arms as well as the downwardly extending T bar connectors  6  engaging a locating recess on the upper surface of the light housing  18 . With this interaction of the T bar connector  6  with the upper surface of the light housing  18 , as well as the retaining spring clips engaging the upper and lower securing beads  36  and  37 , and the interaction due to the insert projection  20  being tightly received in the securing gap  34  of the T bar member, the strip light housing arrangement is releasably fixed to the T bar member  4 . 
         [0036]    Although the strip light housing arrangement  16  is shown in engagement with the T bar member  4  in  FIGS. 6 and 7 , it would normally be the case that the T bar member  4  which in this case is the cross member would be secured to adjacent grid members before the strip light housing arrangement  16  is secured beneath the T bar member. In this way the ceiling grid system can be installed and lighting subsequently secured. Details of this can be appreciated from  FIGS. 10 and 11 . 
         [0037]    A T bar grid system  50  is shown in  FIG. 10  and comprises cross members  54  engaging main T members  52 .  FIG. 10  also shows how the T bar member  4  has replaced one of the cross members  54 . The T bar member  4  is designed to engage the main T  52  in the conventional manner and is essentially a replacement for the cross member  54 . 
         [0038]      FIG. 11  shows a conventional cross member  54  with its own connector engaging the main T  52  and the T bar member  4  having its connector  6  engaging the main T  52 . As shown, the raised elongate connecting member  8  is at a position substantially above the lower surface of a conventional cross T member  54 . This additional elevation is to allow securement with the strip light housing as shown in  FIGS. 12 and 13 . 
         [0039]    In  FIG. 13  it can be seen that the strip light housing arrangement  16  is about to be moved upwardly into engagement with the raised elongate connecting member  8 . Note that the insert projection  20  does not extend the full length of the light housing  18  as there must be room at the ends of the light housing  18  to allow the connectors  6  to engage the upper surface of the light housing. As previously described, the insert projection  20  is forced into the receiving gap  34  in the lower surface of the raised elongate connecting member  8  and the spring clips  211  will engage the upper and lower securing beads  36  and  37  of this member. With this arrangement, the T bar members  4  receive and retain the strip light housing arrangement  16  are provided at predetermined desired locations in the grid system  50 . One such position is shown in  FIG. 12 . 
         [0040]      FIGS. 14 and 15  show the strip light housing arrangement when it is in engagement with the T bar member  4 . The strip light housing arrangement  16  has the light housing  18  positioned below the lower surface  53  of the main T  52 . The light housing  18  includes an upper projecting flange  19  which will support the ceiling panels when they are secured to the grid system. Thus the light housing  18  is positioned below the grid system and is aligned on the structural members of the grid system. 
         [0041]    With the system as shown and described, the structural members defining the ceiling grid are installed without the strip light housing arrangement  16 . The strip lights can be provided or left for the electrical contractor to install. Once the grid system is in place the electrical installer can then properly secure the low voltage power supplies and connect these to the electrical system. Typically the strip light housing arrangement  16  includes a simple snap in cable arrangement to electrically connect the low voltage supply to the strip lights. 
         [0042]    With the present system installation is improved and the strip lighting is installed after the grid system is in place. The strip light housing engages a specialized T bar member, preferably a cross T bar member, and therefore the grid system does not include the strip light housing and the strip light is installed at a later point in time. The specialized T bar members use the same type of connecting clips or bayonets as are well known with existing T bar systems and any accepted connecting arrangement can be used. One such connecting member is shown but the type of connecting member can change, while the structural member cooperates with the strip light housing arrangement for support thereof. 
         [0043]    The use of spring clips is particularly desirable as it simplifies the subsequent installation of the lights and has been found to provide positive releasable securement. If there are any problems with respect to the strip lights they can be easily removed yet they have excellent retention on the T bar members and meet the accepted provisions. 
         [0044]    Although various preferred embodiments of the present invention have been described herein in detail, it will be appreciated by those skilled in the art, that variations may be made thereto without departing from the appended claims.