Abstract:
The invention includes an electrified framework system having a plurality of grid members which form a grid framework. A conductive material is disposed on a surface of at least one of the plurality of grid members as shown throughout the drawings. The system includes connectors which provide electrical connections between the conductive material on the grid framework and various electrical fixtures. The electrified framework system includes a support clip for supporting depending articles suspended from the grid framework into a room space. The support clip does not interfere with the electrical and mechanical actuator controlling the connector and grid interface connection mechanism. The support clip attaches the connector to the grid element such that the connector, and any device attached thereto, will not inadvertently become detached from the grid element during a seismic event.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit under 35 U.S.C. §119(e) of U.S. provisional application Ser. No. 61/192,872, filed Sep. 23, 2008, entitled “Seismic Retention Clip For Underside Connector Of An Electrically Active Grid.” 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention is directed to a support clip, and, more particularly, to a clip which enhances the mechanical and electrical connections between an electrified grid element of the suspended grid framework and a connector suspended therefrom. The clip is particularly useful in the interior building environment in areas of the world which are subject to seismic disturbances. 
       BACKGROUND OF THE INVENTION 
       [0003]    For purposes of illustrating a conventional grid framework,  FIG. 1  shows a portion of a conventional suspended ceiling framework. As shown, the system includes a plurality of grid elements  100  forming the grid framework which, in turn, form polygonal openings into which components such as panels  103 , light fixtures  107 , speakers, motion detectors and the like can be inserted and supported. These grid elements  100  are suspended by support cabling (not shown) to the building infrastructure, such as the overhead deck of the ceiling. Electrical components, such as light fixtures, are typically electrified by means of routing discrete wires, principally on an “as needed” point-to-point basis via conduits, cable trays and electrical junctions located in the space behind the grid framework. These known systems suffer from the drawback that the network of support cables and electrical wires require occupancy of the limited space behind the grid framework. In addition, the cables and wires are difficult to reconfigure and, therefore, provide limited flexibility. 
         [0004]    One attempt to improve flexibility in a grid framework system is described in co-pending U.S. patent application Ser. No. 12/386,215 entitled “Connectors for Electrically Active Grid”. Briefly stated, in accordance with one example embodiment described therein, conductive material is disposed on at least one of the plurality of grid elements and is electrified by a low voltage power source. A depending article, or device, such as a light fixture  108  ( FIG. 1 ) can be electrically connected to the conductive material via a connector which itself is directly attached to a grid element. The depending article connector extends from the grid framework into the room space  109  ( FIG. 1 ) and includes a means for supporting a depending article therefrom. The system is flexible in that the connector can be attached at any location along the electrified grid element. This includes grid intersections. However, such flexibility may be restricted due to other aspects of the ceiling system, e.g. wires and cabling which are difficult to reconfigure. 
         [0005]    Another issue currently inhibiting flexibility of these suspended grid framework systems is the need to support depending devices from these frameworks in areas of seismic activity. It is well understood in the art that in geographic regions of seismic activity additional support of the articles depending from a grid framework, such as the ceiling system shown in  FIG. 1  is required. In other words, to ensure that neither the grid elements nor the depending devices fall out of the system, additional cabling from the grid element and article to the building infrastructure is required. Again, such requirements significantly impede reconfiguration of components of the system, and specifically those components which are attached to the grid and extend into the room space. 
         [0006]    One known support clip for supporting components which are attached to the grid and extend into the room space is shown and described in U.S. Pat. No. 3,599,921 to Cumber. However, use of the clip described therein necessitates attachment of the clip to the building infrastructure located a distance above the suspended ceiling plane. Since such attachment points are not easily accessible from the room space  109  ( FIG. 1 ), any reconfiguration adds to the cost of maintaining the grid framework. Moreover, this additional cabling is separate from, and in addition to, any wiring bringing power to the depending article which needs to be reconfigured. In addition, the support clip described by Cumber cannot be utilized at a grid intersection. 
         [0007]    For the reasons set forth above, increased versatility in the relocation of devices in a grid framework is desired, particularly in view of the increased versatility being engineered into conventional grid framework systems referred to above. The present invention accomplishes all of the needs identified above and provides additional advantages as will be described herein in greater detail. 
       SUMMARY OF THE INVENTION 
       [0008]    One aspect of the invention includes an electrified framework system having a plurality of grid elements forming a grid network. A conductive material is disposed on a surface of at least one of the plurality of grid elements. A depending article is electrically connected to the conductive material via a connector which itself is attached to a grid element. The invention includes a support clip for positively attaching the connector and depending article module to a grid element. The support clip is configured to attach directly to the grid element and to secure the connector to the grid element such that the connector, and any device attached thereto, will not inadvertently become detached from the grid element when seismic forces are applied thereto. The support clip is configured such that it maintains the mechanical and electrical connections of the connector to the grid element when elevated forces, such as seismic forces are applied thereto. The clip is also configured such that it does not interfere with the electrical actuator assembly of the electrical connector which connects or disconnects the electrical connection between the connector and the grid element and does not need to be detached from the framework system. 
         [0009]    Additional advantages of the present invention include: the ability to provide seismic-type support to a variety of depending articles, such as an electrically powered device, to the grid framework without the need for direct attachment of the depending article, or the support clip therefore, directly to the building infrastructure; enhancement of the mechanical connection between a grid member and an electrical connector attached to the grid member, namely the support clips prevent the depending article and connector module from shifting position in the longitudinal direction of the grid element to which it is attached; and the increased versatility in placement of such support clips, and the ease in which they can be mounted and relocated, in the grid framework. 
         [0010]    Other features and advantages of the present invention will be apparent from the following more detailed description of the preferred embodiment, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  shows a perspective view of a room space having an electrified ceiling according to an embodiment of the present invention. 
           [0012]      FIG. 2  shows an elevational perspective view of an example connector attached to a grid element. 
           [0013]      FIG. 3  shows a front elevational view of  FIG. 2 . 
           [0014]      FIG. 4  shows an elevational perspective view of the example connector of  FIGS. 2 and 3 . 
           [0015]      FIG. 5  shows an elevational perspective view of a support clip in accordance with an example embodiment of the invention, the support clip being attached to a grid element and connector. 
           [0016]      FIG. 6  shows a top plan view of  FIG. 5 . 
           [0017]      FIG. 7  shows a side elevational view of  FIG. 5 . 
           [0018]      FIG. 8  shows a front elevational view of  FIG. 5 . 
           [0019]      FIG. 9  shows an elevational perspective view of the example support clip prior to assembly. 
           [0020]      FIG. 10  shows a side elevational view of  FIG. 9 . 
           [0021]      FIG. 11  shows a front elevational view of  FIG. 9 . 
           [0022]      FIG. 12  shows a top plan view of  FIG. 9 . 
           [0023]      FIG. 13  shows a portion of  FIG. 7 , partially exploded, illustrating the optional tab detail on the bottom of the support clip. 
           [0024]      FIG. 14  is a bottom plan view illustrating how the clip is assembled to the grid element and connector. 
       
    
    
       [0025]    Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0026]    For purposes of illustration of the invention,  FIG. 1  shows a portion of a ceiling grid framework comprising a plurality of grid elements  100 . The ceiling grid framework may include decorative tiles, acoustical tiles, insulative tiles, lights, heating ventilation and air conditioning (HVAC) vents, other ceiling elements or covers and combinations thereof being supported by the grid framework. The grid elements shown throughout the drawings are well known in the art and are of the type sold by Armstrong World Industries Inc. in its SIHOUETTE bolt-slot system. Briefly stated, each grid element  100  has: a web portion  111  which for purposes of defining orientation of the components relative one another extends in a vertical plane; and a box-type lower flange  114  extending therefrom. The lower box flange  114  includes: a pair of horizontally extending support flanges  115 ,  115 ′ which extend outwardly from the vertical web portion  111 ; a pair of vertically extending side walls  116 ,  116 ′ extending generally downwardly from the support flanges  115 ,  115 ′; and a pair of horizontally return flanges  117 ,  117 ′ extending inwardly from the side walls in a direction toward one another. The space between the inwardly turned flanges defines a slot  118  for accessing the interior of the box  114 . 
         [0027]    As shown in  FIGS. 2 and 3 , the box  114  includes a pair of electrical conductors  119 ,  119 ′ which are positioned in the interior of the box and are oriented parallel sidewalls  116 ,  116 ′. Preferably, the electrifiable conductors  119 ,  119 ′ have opposite polarity, i.e. one is positive and one is negative. As further shown in  FIGS. 2 and 3 , inserted into the lower box  114  of the grid element  100  is a connector  200 . The connector  200  and grid element  100  interface is flexible in that the connector can be attached to the box  114  at any position along the length of the box. In addition, the interface provides both a mechanical connection as well as an electrical connection. The details of the connector and grid element interface are described in greater detail in U.S. patent application Ser. No. 12/386,215, which is hereby incorporated by reference. 
         [0028]    Briefly stated, the example connector taught in U.S. patent application Ser. No. 12/386,215 and which is shown in the drawings, includes a connector housing  212 . As best seen in  FIG. 4 , the connector housing  212  includes a narrow hanger portion  214  and a wider lower body portion  216 . The connector  200  is installed by first inserting the hanger portion  214  through the slot  118  of the box. The connector  200  is properly seated in the box  114  by pressing the connector  200  up into the interior of the box until the top surface  215  of the lower body portion  216  is in contiguous relation with the outer bottom surface of return flanges  117 ,  117 ′. The top portion  214  of the connector  200  has a pair of contact elements  220  (only one contact element shown) movably mounted thereon for contacting a respective conductor  119 ,  119 ′ housed in the lower box. When the connector  200  is properly seated in the grid box  114 , the contacts  220  are in parallel alignment with the longitudinally extending conductors  119 ,  119 ′ oriented parallel to the sidewalls  116 ,  116 ′ of the box  114 . 
         [0029]    The example connector  200  includes an actuator  230  which is rotatable and includes a pair of wings  232 ,  232 ′ extending therefrom. The winged actuator  230  is rotatable between a first position X (as seen in  FIGS. 3 and 4 ) and a second position Y (as seen in  FIGS. 5 ,  7  and  8 ). It is important to note that the actuator  230  is rotatable without having to rotate any other portion of the housing  212 . When the actuator is in the first position X, the connector can be inserted into slot  118 . When the rotator is then moved to a second position Y, the connector becomes both mechanically and electrically connected to the grid element. More specifically, the example connector  200  shown includes a cam member  240  mounted on the winged actuator  230  which interposes the pair of resilient spring contact elements  220 . Thus, when the connector is moved from position X to position Y, the cam member  240  urges the contact elements against the conductors in the box, thereby providing both a mechanical and electrical connection. The connector can become electrically and mechanically disconnected from the grid member by rotating the rotator wings in the opposite direction which, in turn, allows the cam/gear to disengage and the expandable hanger and spring contacts to retract into their original unexpanded position. 
         [0030]    In addition to the electrical connection provided by the connector between the conductors on the grid element and an article depending therefrom, the connector is designed to provide a means for supporting the article. Fixture mounting hardware, such as a conventional threaded stud  250  projects through the bottom of the connector housing  212  to which a depending article  107  such as a camera or lighting device may be mechanically secured by means of a wing nut  260 , for example. The underside of the connector can optionally include other fixture mounting hardware such as strain reliefs, nipples, etc. for attaching a fixture, such as a pendant light, to the connector. 
         [0031]    With respect to various Figures, and particularly  FIG. 5-12 , there is an example support clip  300  which provides a means for supporting the connector shown in  FIGS. 2-4 , and, in turn, a depending article  107  thereto, below the grid elements  100  of a suspended grid framework. Moreover, the clip allows the mechanical/electrical connection between the connector and grid described above to be removed but keeps the connector, and in turn, the depending article attached to the connector, physically connected to the grid element. 
         [0032]    The support clip  300  is preferably formed of a resilient sheet material such as a spring steel strip. As best seen in  FIG. 9-12 , the body of the support clip includes a grid engaging portion  310  which is configured to be assembled to a longitudinally extending grid element  100 , and, specifically, the vertical web and box-type flange of a grid element as shown in  FIGS. 6-8 . In general, the grid engaging portion  310  overlies only one side of the grid element and, as will be more evident from the features therein described below, prevents the connector/depending article module from sliding longitudinally along the length of the grid member as well as from pulling away vertically when forces are applied to the connector/depending article module in these respective directions. Moreover, the foregoing support clip is designed to directly attach to the grid but does not require the grid engaging portion  310  to go over top, e.g. hook over, the top of the grid element. This feature is particularly important as it eliminates the potential of the grid engaging portion  310  shorting the electricity where electricity is being transported by the electrified grid element via electrical buses provided at or near the top portion of the grid element. 
         [0033]    The grid engaging portion  310  includes a rectangular longitudinally extending offset  315  for receiving the like-shaped cross section of the grid element. This offset  315  can be formed in any shape to conform to the shape of a grid element, however, conformity is preferred to avoid interfering with the mounting or removal of ceiling panels  103  and the like from the polygonal grid openings. As shown, the offset  315  conforms substantially to the sidewall, e.g.  116 , and the horizontal flange, e.g.  115 , of the flange box  114  of the grid element  100 . 
         [0034]    The grid engaging portion  310  also includes a top portion  320  which extends vertically and is integral to the offset portion  315 . When the clip is attached to grid element  100 , the top portion  320  preferably conforms substantially, and is positioned in a plane in parallel relation, to the vertical web of the grid element. To avoid having to support the clip directly to the infrastructure of the building interior, e.g. the ceiling deck, the top vertically extending portion  320  includes an aperture  322  ( FIGS. 9 and 10 ) into which a screw-type fastener  324  ( FIGS. 5-8 ) can pass through and then be mechanically fastened to the vertical web  111  of the grid element  100  so that the clip is positively attached to the grid element. The vertical web portion  111  may include an aperture to mate with the aperture  322  in the top vertically extending portion  320  of the grid engaging portion  310 . By positively securing the grid engaging portion  310  to the vertical web of the grid element, the connector/depending article module is prevented from sliding longitudinally, which otherwise would only be restricted from moving longitudinally in the grid box flange by frictional force via the attachment mechanism of the connector in the grid box as described herein. 
         [0035]    The grid engaging portion  310  further includes a base portion  325  which extends horizontally and conforms generally to one of the lower in-turned flanges, e.g.  116 , of the box  114 . As shown in the example embodiment, the offset  315  and base  325  essentially form a longitudinally extending C-shaped offset portion which mates with the lower box of the grid element. Further, the base portion is positioned such that the top vertically extending portion  320  is positioned above the base portion. 
         [0036]    As best seen in  FIG. 10 , extending from an edge  330  of the base portion  325  in a direction generally perpendicular the top portion  315 , and in turn the vertical web  111  of the grid element, is a connector engaging member  340  which mates with, i.e. parallels, both a sidewall and bottom surface of the connector which surfaces are positioned below, and in parallel alignment with, the longitudinally extending grid element. In the example configuration shown throughout the several views, the engaging member  340  is bent at a right angle to conform to the box-shape of the connector  200 . As best seen in  FIGS. 9 ,  10  and  12 , the engaging member  340  is longitudinally offset from the grid engaging portion  310  and extends, at least initially, generally perpendicular to the vertical plane of the vertical web portion  111  of the grid element when the clip is attached to the grid as shown in  FIG. 5 . 
         [0037]    Similar to the upper body portion contouring to the grid element, the components of the lower body portion are configured to mate with and contour to the connector so that the clip neither interferes with the insertion or removal of devices, such as ceiling panel, in the grid openings formed by the grid framework ( FIG. 1 ). As can be seen in the various views, the cradling member  340  lies in substantially the same vertical plane as the vertical web portion of the grid element and therefore does not interfere with the winged rotator so that the wings can be swung to and from positions X and Y as described above. The engaging member  340 , via its orientation relative the vertical web portion  111  of the grid element  100 , prevents the threaded stud from sliding in the grid box  114  in both longitudinal directions. Without the support clip, there would be no positive lock, except friction, to prevent the connector from moving longitudinally in the grid box flange  114 . 
         [0038]    As illustrated in  FIGS. 9 and 12 , the engaging member  340  has a cut out extending from an edge thereof to receive the shaft of a threaded stud  250  of the connector. This cutout is critical in easily assembling the support clip to the grid element and connector assembly. As best seen in  FIG. 15 , this cut out allows the support clip to be assembled to the grid element and connector via a single horizontal rotation in the direction indicated by the arrows. Such ease in installation is important to the flexibility that an electrified grid system requires. 
         [0039]    While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. 
         [0040]    For example, the grid engagement portion of the clip body could be bent to conform to any shape of the lower box flange of the grid element. For example, the box may be of generally curved configuration, thus, not requiring the fourth portion to be bent at generally right angles as is necessary to conform to a box-shaped lower support flange of a grid element. In addition, a second support clip, having the exact same configuration as the first clip can be attached to the grid/connector on the opposing side of the connector. A second clip will provide additional reinforcement and resist forces applied transverse to the grid in both directions (e.g. enhanced pull-out perpendicular to the horizontally extending grid framework is provided). 
         [0041]    Another optional feature of the support clip  300  is the tabs  360  shown in  FIGS. 13 and 14  which protrude outwardly from the cradling member  340  adjacent the cut out. These tabs  360  are captured within a nut  260  when the nut is screwed onto the threaded stud  250 . Two example configuration of the interface of these tabs and the nut are as follows: 1) the nut can include a grove that traps the tabs or the nut can have a wedge that bites onto the tabs when the nut is tightened. Both of these options provide enhanced positive locking of the bracket to the connector. In turn, these options provide increase the strength of the connection of the connector to the grid element.