Abstract:
An apparatus and method for mounting luminaires (A) includes a lower mounting plate ( 30   a ) having a front face ( 32   a ) and a back face ( 34   a ) adapted for attachment to a luminaire. An upper mounting plate ( 30   b ), having a front face ( 32   b ) and a back face ( 34   b ), is adapted for attachment to an electrical assembly ( 20 ). The upper and lower mounting plates are identical in configuration. The upper mounting plate selectively engages the lower mounting plate so that the upper mounting plate and the lower mounting plate are in locking relation. A hinge ( 50 ) operatively connects the upper and lower mounting plates. The hinge is adapted to swing down and suspend the luminaire while the appropriate electrical connections are made and pivot to a substantially horizontal position once the upper and lower mounting plates have been placed in locking relation.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention pertains to an apparatus and method for improving the performance of mounting brackets for lighting fixtures. More particularly, this invention relates to a thin profiled mounting bracket, for permanently mounting luminaires to a junction box, which is capable of suspending a luminaire during installation and deterring vandalism and theft upon completion of installation. 
     2. Discussion of the Art 
     Luminaires have a number of applications and are widely used for architectural and outdoor lighting, as well as indoor lighting applications. For example, streets, sidewalks, and parking lots often require luminaires to provide adequate lighting. A conventional luminaire includes a housing for enclosing and protecting electrical components of the luminaire. Electrical wires typically extend from a portion of the luminaire for connection to an electrical junction box, commonly referred to as a J-box. The electrical junction box is mounted to any structure requiring a lighting fixture, such as a ceiling of a parking garage, a post on a street, or a tree in a park. Once the appropriate wire connections are made, the luminaire is mounted to the junction box through a mounting assembly. Known devices for mounting a luminaire to an electrical junction box include a bracket secured to the luminaire which is adapted to fit over and attach to the junction box through the use of fasteners. 
     Luminaires designed for use in large areas, such as underground parking garages, parks, and highways, are relatively heavy and cumbersome. In addition, luminaires and their associated circuitry are usually located at substantial heights above the ground. As such, two people are generally required to mount the luminaire to the junction box. The first person holds the luminaire in position while the other person completes the electrical connection and secures the bracket to the junction box. In addition, routine repair, maintenance, and adjustment procedures often require two people to perform work on a heavy luminaire. With the cost of labor rapidly escalating, especially for commercial construction workers, the use of known mounting devices for luminaires has become expensive. 
     Adding to the expense of maintaining luminaires are costs associated with vandalism, theft, and inadvertent damage caused by unstable mounting mechanisms. Because luminaires are used in exposed public environments where security is minimal, they are prone to theft and vandalism. Furthermore, luminaires often undergo elevated levels of vibration, such as that generated by inadvertent bumping or heavy vehicles traveling in a parking garage. The vibration may disturb the attachment of the luminaire to its mounting device. 
     In order to alleviate the foregoing problems associated with conventional mounting devices, one known mounting bracket has hooks extending therefrom. The bracket is mounted to a junction box and the hooks are adapted to penetrate the housing of the luminaire and suspend the luminaire while the electrical connections are made. After the electrical connections have been made, the hooks are received in pockets of the luminaire. At this point, the fixture is locked to the junction box and cannot be removed without internal access through the ballast compartment. 
     There are a number of significant shortcomings associated with the foregoing mounting device. First, the hooks that suspend the luminaire during installation penetrate directly into the housing once the luminaire has been permanently mounted. This creates a potential undesired path for water and moisture to enter the fixture thereby causing early luminaire failure. Second, this device is complex having a number of different parts that are expensive to manufacture. Moreover, the mounting bracket is relatively large and bulky having a thick profile. 
     Thus, a need exists to provide a thin profiled mounting bracket capable of suspending a luminaire during installation, deterring theft and vandalism, preventing water from penetrating the luminaire housing, and that is economical to manufacture and use. 
     BRIEF SUMMARY OF THE INVENTION 
     A new and improved apparatus and method is provided for mounting luminaires that meet the foregoing needs. 
     An exemplary embodiment inventive luminaire mounting bracket includes a first or lower mounting plate having a first or front surface and a second or back surface adapted for attachment to a luminaire. A second or upper mounting plate has a first or front surface and a second or back surface adapted for attachment to an electrical assembly. The upper mounting plate selectively engages the lower mounting plate so that the upper mounting plate and the lower mounting plate are in locking relation, thereby forming a thin profile. A hinge operatively connects the upper mounting plate and the lower mounting plate. The hinge is adapted to suspend the luminaire while the appropriate electrical connections are made and before the upper and lower mounting plates are brought into locking relation. 
     The luminaire mounting bracket preferably includes upper and lower identical mounting plates adapted to mate together in locking relation. 
     An exemplary method for installing a luminaire in a hands-free mode includes mounting an upper mounting plate to an electrical box. A lower mounting plate is mounted to a housing of the luminaire. The upper mounting plate and the lower mounting plate are interconnected via a hinge adapted to suspend the luminaire during installation and maintenance operations. Electrical wires protruding from the housing of the luminaire are coupled to electrical wires extending from the electrical box. The hinge is collapsed and the upper and lower mounting plates are placed in locking relation. 
     One advantage of the present invention is the provision of a mounting bracket for a luminaire capable of suspending the luminaire during installation and routine maintenance. 
     Another advantage of the present invention resides in the ability of the mounting bracket to deter vandalism and theft. 
     Still another advantage of the present invention is the provision of a mounting bracket which does not penetrate the housing of the luminaire. 
     Still another advantage of the present invention is the provision of a mounting bracket having a reduced number of components and identical mounting plates thus significantly reducing manufacturing costs. 
     Yet another advantage of the present invention is the provision of a mounting bracket having a thin profile. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a mounting bracket in accordance with the present invention operatively connecting a luminaire to a junction box in suspended relation 
     FIG. 2 is a perspective view of the mounting bracket of FIG. 1 operatively connected to a junction box; 
     FIG. 3 is a plan view of a hinge in accordance with the teachings of the present invention; and 
     FIG. 4 is a perspective view of a mounting bracket in a collapsed position operatively connected to a luminaire. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows a luminaire A in accordance with the present invention. The luminaire A includes a translucent housing, such as a polycarbonate window or lens  12  and a housing  14  enclosing the electrical components of the lamp. The lens and housing direct light into a bounded area in a manner well known in the art. The illustrated housing has smooth contours and a substantially planar top surface  16 , although it will be appreciated that a number of different housing styles can be used without departing from the scope and intent of the invention. A first set of electrical wires (not shown) extend from the interior of the housing  14  through the planar top surface of the housing. 
     An electrical assembly, such as a junction box or J-box  20 , operates to provide electrical power to the luminaire A. The junction box  20  may be mounted in any number of environments where illumination is required, such as a parking garage, street, or park. In order to provide power to the luminaire, a second set of electrical wires (not shown) extend from a conduit (not shown) into the junction box  20  and are adapted for electrical connection to the first set of electrical wires of the luminaire. Thus, electrical power is transmitted from the junction box  20  to the luminaire. Although FIG. 1 shows a junction box having a particular size and shape, it will be appreciated that any conventional electrical assembly or junction box may be used without departing from the scope and intent of the present invention. 
     With continued reference to FIG. 1, and further reference to FIG. 2, a low profile mounting assembly or bracket B suspends the luminaire A while the electrical connections are being made, thereby eliminating the need for the installer to hold the fixture while also making the electrical connections. Thus, only one person is needed to install and perform work on the luminaire since the bracket advantageously supports or suspends the luminaire and provides a hands-free mode of operation. After the appropriate electrical connections have been made, the bracket B collapses into a thin profile. In the collapsed position, the bracket functions to effectively mount the luminaire A to the junction box  20  in such a manner that theft, vandalism, and inadvertent detachment are minimized. 
     FIGS. 1 and 2 show the bracket B in its original, uncollapsed position. The bracket includes a first or lower mounting plate  30   a  which is operatively connected to the top planar surface  16  of the housing  14 . A second or upper mounting plate  30   b  is operatively connected to the junction box  20 . In the preferred embodiment, the mounting plates  30   a ,  30   b  are identical thereby significantly reducing the cost of manufacturing the bracket. Since the mounting plates are identical, like components will be identified by like numerals with an “a” or “b” suffix for ease of reference to the first and second mounting plates  30   a ,  30   b , respectively. Each mounting plate has a first or front face  32   a ,  32   b , respectively and a second or back face  34   a ,  34   b , respectively. The back face  34   a  of the lower mounting plate  30   a  is oriented for direct, abutting engagement with the luminaire housing top surface  16 , while the back face  34   b  of the upper mounting plate  30   b  is oriented for direct, abutting engagement with a bottom surface of the junction box  20 . Thus, the front face  32   a ,  32   b  of each mounting plate is disposed in facing relation to one another. 
     The mounting plates  30   a ,  30   b  include a series of mounting holes  36   a ,  36   b  for receiving fasteners (not shown). The fasteners attach the lower mounting plate  30   a  to the luminaire A and the upper mounting plate  30   b  to the junction box  20 . Any conventional fasteners may be used in conjunction with the present invention. The fasteners that connect the lower mounting plate to the luminaire preferably do not pass into the housing of the luminaire. Instead, bosses or blind end recesses (not shown) are provided in the housing for receiving the fasteners to limit the number of openings (and potential leak paths) into the housing. As such, this structural feature simultaneously saves on space required for the mounting bracket and does not provide a path for water ingress or pooling as noted above. 
     Each mounting plate  30   a ,  30   b  further includes a slot  42   a ,  42   b  which allows the electrical wires to pass from the luminaire A, through the bracket B, and into the junction box  20 . Alternatively, each mounting plate may include an embossed section having a hole punched therethrough for allowing the electrical wires to pass through the bracket. Each mounting plate further includes at least one lip  44   a ,  44   b  extending in substantially perpendicular relation from an edge of the mounting plate. In the illustrated embodiment, two lips are shown in each mounting plate which are separated by the slot  42   a ,  42   b . The lips  44   a ,  44   b  of each mounting plate include a set of apertures  46   a ,  46   b  for reasons that will become more apparent below. 
     With continued reference to FIGS. 1 and 2, and further reference to FIG. 3, a substantially U-shaped hinge  50  functions to connect the lower and upper mounting plates  30   a ,  30   b  together. The U-shaped hinge has a pair of legs  52 ,  54  disposed in generally parallel relation interconnected by a bridge  56 . An end  58  of each leg  52 ,  54  projects outwardly so that the legs form the shape of an “L”, although it will be understood that still other angles or shapes can be used without departing from the scope and intent of the present invention. In the exemplary embodiment, the hinge is made from an elastic wire material. As such, the L-shaped legs can be pressed together allowing them to be inserted through both sets of apertures  46   a ,  46   b  defined by the lips  44   a ,  44   b  of each mounting plate. After the legs have been inserted through both sets of apertures, the L-shaped ends expand thereby locking the hinge to the lower mounting plate  30   a . At this point, the bracket is in an uncollapsed position (i.e., the mounting plates are secured together via the hinge) and the mounting plates are disposed in spaced relation and capable of suspending the luminaire without any additional structure. This allows a single installer to easily make the appropriate electrical connections once the luminaire is suspended from the junction box via the mounting bracket. 
     Once the electrical connections have been made, the hinge  50  is pivoted so that the mounting plates  30   a ,  30   b  are brought together from the orientation shown in FIGS. 1 and 2 to form a thin profile with the hinge disposed between the two mounting plates as shown in FIG.  4 . In order to secure the mounting plates together, the mounting plates each have a series of fingers  60   a ,  60   b  offset from the remainder of the plane of the mounting plates. The fingers  60   a  of the lower mounting plate  30   a  are adapted to slide into a mating relationship with the fingers  60   b  of the upper mounting plate  30   b . To prevent the fingers from disengaging, a spring clip  64  (see FIG. 2) is mounted on the upper mounting plate  30   b . When the mounting plates are slid together, the spring clip passes over a screw  66  (see FIG. 1) protruding from the lower mounting plate  30   a . Once the spring clip passes the screw, the mounting plates are locked into place and can only be unlocked by retracting or backing out the screw. Thus, vandalism, theft, and accidental detachment are minimized since the screw  66  is accessible from inside the luminaire only. The bracket in its fully collapsed position is best seen in FIG. 4 with the electrical box omitted for ease of illustration. 
     In operation, the lower mounting plate  30   a  is attached to the luminaire A and the upper mounting plate  30   b  is attached to the junction box  20 . The L-shaped legs of the hinge  50  are then inserted through both sets of apertures  46   a ,  46   b  of each mounting plate thereby connecting the luminaire to the junction box via the bracket B. As such, the luminaire is suspended which allows the electrical connections to be made without having to manually support the luminaire. Once the appropriate electrical connections have been made, the upper and lower mounting plates are slid together so that the fingers  60   a ,  60   b  of each mounting plate are in mating relation as described above. While the mounting plates are slid together, the spring clip  64  slides over the protruding screw  66  so that the two mounting plates are locked together. In order to disengage the mounting plates from locking relation, the screw must be backed out from inside the luminaire. 
     The invention has been described with reference to the preferred embodiment. Obviously, modifications and alterations will occur to others upon a reading and understanding of this specification. The invention is intended to include all such modifications and alterations in so far as they come within the scope of the appended claims and the equivalents.