Abstract:
A support plate for a luminaire of unitary construction includes a planar member portion having a centrally disposed opening therein and a pair of recessed U-shaped cross bar supports adjacent opposed edges of said opening to receive mating end portions of a luminaire support bracket.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a lighting fixture hanging system and more particularly to a support plate for a luminaire. 
     A large number of devices have been provided for hanging light fixtures from room ceilings. Many of these lighting fixtures, such as luminaires, are hung directly to an electrical box, which is concealed above the ceiling. These electrical boxes are positioned so that the lighting fixtures can be wired directly to the electrical wires extending from the boxes. However, luminaires (fixtures) weighing 25 pounds or more are very often too heavy to mount directly to typically installed outlet boxes. Support plates attached to the ceiling may also be provided for detachably connecting luminaires or other support assemblies for luminaires to the ceiling and in turn the electrical outlet boxes. The support plates for the lighting fixtures, and the like, are fixedly attached to the ceiling and in making the detachable connections of the lighting fixtures, connecting devices are generally not easily accessible and can become cumbersome in repairing or replacing one lighting fixture with another. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a support plate for a luminaire for detachably receiving a luminaire support bracket. 
     It is another object of the present invention to provide a support plate for a luminaire which is relatively inexpensive, easy to install and provides easy access for detachably connecting luminaire supports. 
     The present invention provides a support plate to hang a luminaire from a ceiling. The support plate is fastened to the ceiling for support of a luminaire, crossbar or luminaire support bracket, and an outlet box. The support plate includes a recessed area for clearance of the crossbar or luminaire support bracket. 
     More particularly, the present invention provides a support plate for a luminaire, which includes a planar member having a centrally disposed opening therein. A pair of U-shaped crossbar supports is positioned adjacent opposed edges of the opening and disposed within the opening. Each of the crossbars is recessed in relation to the outer periphery of the planar member and extends from the edges of the opening. The spaced crossbars are disposed to receive a luminaire support bracket to which a luminaire, such as a chandelier or the like, is attached. 
    
    
     Additional objects, features, and advantage of the invention will become apparent to those skilled in the art upon consideration of the following detailed description exemplifying the best mode of carrying out the invention as presently perceived. The detailed description particularly refers to the accompanying figures in which: 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a lighting fixture hanging system including a support plate of the present invention; 
     FIG. 2 is a perspective view of the lighting fixture hanging system of FIG. 1 with the housing for the luminaire support bracket removed; 
     FIG. 3 is a perspective view of a support plate of the present invention as seen from the top surface of the support plate with a luminaire support bracket in place; 
     FIG. 4 is a perspective view of the support plate of FIG. 3 as seen from the bottom surface of the support plate with a luminaire support bracket in position; and, 
     FIG. 5 is a top view of the support plate of FIGS.  3  and  4 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to FIGS. 1 and 2 of the drawings, a lighting fixture is shown attached to a ceiling which may be made of plywood, sheet rock, or the like, for supporting a lighting fixture directly thereto. As shown in FIG. 1, a canopy  50  is provided to encase a support plate  10  and a luminaire support bracket  14 . An elongated luminaire hanging pole, identified by the numeral  52 , is threadably attached to a swivel ball  26  which is received within an opening  30  in the luminaire support bracket  14 . 
     As shown in FIGS. 2-5, the support plate  10  is provided with a plurality of mounting holes  12  for mounting the support plate to the ceiling, the plate forming a flat planar surface or member  11  which supports the luminaire to the ceiling. The support plate  10  is provided with a pair of crossbar supports  16   a  and  16   b  for receiving the outwardly extending support ends  15   a  and  15   b  of the luminaire support bracket  14 . Crossbar supports  16   a  and  16   b  may be recessed out of the plane formed by the support plate  10  by legs  18   a - 18   d . Each of the outwardly extending ends  15   a ,  15   b  of the luminaire support bracket  14  is disposed to be received by the crossbar supports  16   a  and  16   b . Ends  15   a  and  15   b  are provided with flanges  38   a ,  38   b  for engaging with outer edges of the crossbar supports  16   a  and  16   b . The flanges  38   a  and  38   b  are also provided with openings therein to receive crossbar screws  40   a  and  40   b , allowing canopy  50  to be secured to the luminaire support bracket  14  and hold canopy  50  adjacent to the ceiling. 
     The luminaire support bracket  14 , being of U-shaped construction, includes a recessed support section  42  in which a swivel ball receiving opening  30  is disposed therein. A slotted opening  32  is provided in one of the vertical walls  34   a  or  34   b  for receiving the swivel ball  26 . 
     As best shown in FIG. 5, the support plate  10  is provided with crossbar support legs  18   a ,  18   b ,  18   c , and  18   d  which attach the crossbar supports  16   a  and  16   b  within the opening  20  of the plate  10 . Crossbar support legs  18   a ,  18   b ,  18   c  and  18   d  may be angled at 45° relative to the planar support plate  10  thus forming the recessed area for clearance of crossbar supports  16   a  and  16   b . The recessed area defined by the support legs may extend outward from about 0.08 inch, more or less, depending on the thickness of the material forming the support plate  10  and the support bracket  14 . Thus, legs allow the support bracket to be recessed into the same plane defined by the plate  30 . The crossbar supports  16   a  and  16   b  are also provided with slots  22   a  and  22   b  therein which are in mating relation with slots  54   a  and  54   b  in the ends  36   a  and  36   b  of the luminaire support bracket  14  for maintaining the luminaire support bracket  14  in a fixed position. Slots  22   a ,  22   b  are angled inwardly in line with a center point of the opening  20 . An opening  20 , generally of rectangular configuration, is also provided with opposed elliptically-shaped outer edges  44   a ,  44   b , which provides for the ease of electrical connection/installation of the luminaire support bracket  14  therein, the luminaire support bracket  14  being inserted through the opening  20  for mounting onto the crossbar supports  16   a  and  16   b . The opening  20  has a length greater than a width, and the crossbar supports  16   a ,  16   b  with legs  18   a ,  18   b ,  18   c ,  18   d  extending across the width of opening  20 . Cut outs  24   a  and  24   b  at opposed ends of opening  20  and equal distance from each corner of the opening  20  is provided to allow clearance of screws  40   a  and  40   b  during assembly. 
     Although the invention has been described in detail with reference to a preferred embodiment and a specific example, variations and modifications exist within the scope and spirit of the invention as described and defined in the following claims.