Abstract:
An abuse-resistant light fixture housing having a mounting plate with mounting brackets, a frame having an opening for a-non opaque cover, and a plurality of fasteners affixing the mounting bracket to the frame is provided. When the mounting plate and frame are assembled together the frame is suspended apart from the mounting bracket such that impacts against the frame are absorbed by the suspension elements allowing the frame and light elements to survive generally undamaged. Elements of the fixture are made so as to resist damage while providing illumination.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a fixture housing for a light source, and particularly to a durable, suspension mounted light fixture that is resistant to damage caused by physical abuse, vandalism or tampering. 
     BACKGROUND OF THE INVENTION 
     It is generally well-known that furnishings used inside certain buildings, such as schools, athletic facilities and stadiums, correctional institutions, detention facilities, hospitals and universities are frequently subject to heightened wear and often times intentional or unintentional physical abuse. Despite this well-known fact, many government and business entities commonly use low-cost, bulky overhead lighting and light fixtures in connection with large-scale commercial, municipal or recreational buildings. 
     Unfortunately, the typically low-cost overhead lights and light fixtures that are used are often not robust enough to withstand the physical abuse to which they are subjected. The result is that these light fixtures are regularly and repeatedly damaged or destroyed needing to be repaired or replaced. Repeatedly repairing or replacing light fixtures is costly and time consuming, and is disruptive to the use of the space in the location of the damaged fixture. Fixtures vulnerable to damage from physical impact can also be a danger to individuals that happen to be in close proximity at the time the damage takes place. Such persons can be harmed by broken glass or metal from the fixture, and, in the case of fluorescent lighting, can also be exposed to toxic particles that become airborne when fluorescent tubes are ruptured. People near a damaged fixture also risk electrocution from exposure to wires and other electrical components. 
     One of the primary reasons that these types of lights are so susceptible to damage is that they use a fragile lamp or tube that is either openly exposed to the surrounding environment, or shielded only by a flimsy or unsupported cover. Another reason is that the frame of the fixture itself is rigidly affixed to the mounting surface and thus has no flexibility such that when the fixture is impacted by an object or person the force of the impact causes damage. Accordingly, when subjected to even slight forces the frame, cover or mounting elements of such fixtures can be easily damaged. 
     As an alternative to the ordinary light fixtures described above, light emitting diodes (LEDs) are becoming more common in home, commercial and institutional settings. Compared to traditional light sources, LEDs when used together in LED array panels have several advantages. LEDs are high in efficiency, since as will be understood by persons having skill in the art the energy used by LEDs is used to generate light generally and not on producing heat. In addition, it has been found that LEDs typically have a much longer life than traditional incandescent bulbs such that they need not be replaced as often as incandescent or fluorescent bulbs. However, LED array panels are typically very expensive and in their current state of technology are quite fragile such that there use as a replacement for ordinary fixtures in the situations described above is premature. 
     Accordingly, there is a need for an economical and highly durable light fixture that is resistant to damage caused by physical force, vandalism or tampering. Objects and advantages of the present invention will become apparent as the description proceeds. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention an abuse resistant light fixture housing is provided. The housing includes a mounting plate and cooperative frame wherein the mounting plate has at least one bracket with a deflectable element and at least one fastener. The frame of the housing further defines fastener mounting points adjacent to each of the at least one brackets when the frame and mounting plate are in cooperative engagement. The deflectable elements of the brackets have cooperative fastening means such that when the at least one fastener is placed in a fastener mounting point in the frame and fastened to the adjacent cooperative fastening means on the bracket, the frame is flexibly attached to the mounting plate so that when the frame is struck the brackets deflect to absorb the energy of the strike. In effect, the frame is suspended from the mounting plate in a manner that allows the frame to move in response to being struck rather than crumple. 
     In the preferred embodiment, the light fixture housing includes a light fixture within the frame and a separate protective abuse resistive lens. To protect the light fixture it is attached to the frame or suspended element of the invention. The light fixture and protective abuse resistive lens are spaced apart, in the preferred embodiment to create a further energy absorbent gap there between. In some embodiments the frame defines low profile angular edges to minimize areas of direct impact on the frame, allowing for glancing blows instead. 
     With respect to the connection between the mounting bracket and frame, fasteners are threaded to connect the frame and the brackets; the brackets include cooperative threading means to engage the fasteners. In some embodiments the fasteners and the cooperative fastening means on the brackets cooperatively snap together. 
     In some embodiments of the present invention the frame includes a flange and the mounting plate defines a perimeter, and the mounting plate perimeter and frame flange are adjacent one another and spaced apart when the frame and mounting plate are in operative cooperative engagement so as to form an energy absorbing gap between the frame and mounting plate. The gap permits the elements of the fixture to flex without damaging each other. 
     In a preferred embodiment, the frame is created of steel and the seams of the frame are welded for strength. The cover is comprised of a material selected from the group consisting of glass, reinforced glass, polycarbonate, fiberglass, plastic and fiberglass reinforced plastic. 
     According to additional embodiments of the present invention, the fixture includes a light source, such as for example a light emitting diode (LED). The light source is arranged in such a way as to provide light through the non-opaque cover of the fixture so as to illuminate areas near the fixture. In one embodiment, the light source has a substantially planar configuration that covers a substantial portion of the adjacent cover. The cover and light source are secured within the fixture by a retainer plate and a plurality of fasteners around the aperture in the frame. 
     It is a benefit of the present invention to provide a highly-durable light fixture that is capable of withstanding harsh treatment or physical abuse caused by individuals in close proximity. This benefit is in part achieved by the compact design and durable suspension mounting arrangement between the frame and the back plate. According to this arrangement, the frame of the fixture is mounted indirectly to the back mounting plate by angled mounting brackets, as opposed to being directly affixed to a particular mounting surface. This arrangement enables the frame of the fixture to move slightly in order to absorb an impact, thus making the fixture more resistant to various forces exerted upon it by deflecting upon impact to absorb energy without transmitting potentially destructive force to fragile internal lighting components. 
     Another benefit of the claimed invention is to provide improved illumination to areas proximate the fixture, while at the same time utilizing less energy than an equivalent high intensity lamp. In addition, the fixture has a compact design that requires minimal overhead space, and is thus highly desirable over bulky florescent fixtures in applications with limited space. An additional benefit is to provide a safe light fixture that does not contain any potentially harmful contaminants, such as for example mercury or lead, that can potentially leak into the environment. 
     Additional advantages of the claimed fixture include its versatility and visually appealing characteristics. The fixture can be produced in various standard or customized sizes or shapes and can be used in connection with a variety of settings including but not limited to schools, athletic facilities and stadiums, correctional institutions, universities, hotels, hospitals, factories and offices, conference or meeting rooms, or any other residential, commercial or industrial settings. In addition, the fixture can be used for decorative or commercial purposes by utilizing an artificial light source or cover with different colors or decorative designs. Such designs can include commercial signs, slogans or trademarks for advertising or marketing purposes. 
     Further objects, features and advantages of the present invention will be apparent from the following description and the appended claims when taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view of a fixture according to one embodiment of the present invention. 
         FIG. 1   a  is a perspective view, partially broken away, of a mounting bracket of the present invention. 
         FIG. 2  is a cross sectional view of the fixture of  FIG. 1  taken along the plane of line  2 - 2  in  FIG. 1 . 
         FIG. 3  is a cross sectional view of the frame of the fixture according to one embodiment of the present invention. 
         FIG. 4  is a side elevational view of the mounting plate of the device of the present invention according to one embodiment of the present invention. 
         FIG. 5  is a plan view of the front side of the mounting plate of  FIG. 4 . 
     
    
    
     DETAILED DESCRIPTION 
     While the present invention is susceptible of embodiment in various forms, there is shown in the drawings a number of presently preferred embodiments that are discussed in greater detail hereafter. It should be understood that the present disclosure is to be considered as an exemplification of the present invention, and is not intended to limit the invention to the specific embodiments illustrated. It should be further understood that the title of this section of this application (“Detailed Description”) relates to a requirement of the United States Patent Office, and should not be found to limit the subject matter disclosed herein. 
     In this disclosure, the use of the disjunctive is intended to include the conjunctive. The use of the definite article or indefinite article is not intended to indicate cardinality. In particular, a reference to “the” object or “an” object is intended to denote also one of a possible plurality of such objects. 
     Referring now to the figures, and specifically to  FIGS. 1-2 , there is shown a light fixture  10  suitable for affixation onto a wall or ceiling. Fixture  10  comprises a mounting plate  12  and a frame  30  which when assembled together form a housing  19  having an interior cavity  29 . Mounting plate  12  and frame  30 , in a preferred embodiment are constructed of up to 14 gauge cold rolled steel or 304 stainless steel, however it will be understood by persons having ordinary skill in the art that steel of a gauge suitable for lamp fixtures and specifically to fixtures subjectable to violent force or any durable substantially rigid material such as, for example, other metals or alloys polycarbonates and/or other materials known to persons having ordinary skill in the art can be used without departing from the novel scope of the present invention. In other embodiments the gauge of the steel can be increased as security demands or decreased as needed. Further, among the other types of steel that can be used, without limitations, are high strength steel alloys and half hard steel. In a preferred embodiment all external seems of housing  19  are welded and ground to provide structural integrity, strength and security for the fixture. 
     While light fixture  10 , mounting plate  12  and frame  30  are illustrated in the figures as having a generally rectangular shape it will be understood by persons having ordinary skill in the art that the device of the present invention can be made in other shapes or configurations and in a variety of sizes without departing from the novel scope of the present invention. 
     As shown in  FIGS. 1 ,  2  and  4 , the mounting plate  12  comprises a back side  14 , a front side  16  and defines a perimeter  18 . Back side  14  of mounting plate  12  can be made such that when installed it lies flush against the mounting surface to which it is affixed when the fixture  10  is installed. Alternatively, in other installations, when fixture  10  is installed, mounting plate  12  can hang or otherwise be suspended from a mounting surface, as desired. Referring to the figures, it will be seen that mounting plate  12  includes one or more openings  13  to allow for electrical wiring, such as a power cord, to pass from the interior cavity  29  of the fixture  10  to a power source outside the fixture  10 . 
       FIGS. 1-2  and  4 - 5  show mounting brackets  20  affixed to the front side  16  of the mounting plate  12 . As best illustrated in  FIGS. 1   a  and  2 , a mounting bracket  20  is a generally “L” shaped member having a base portion  22  affixed to mounting plate  12 , a raised portion  23  and an arm portion  26  extending out from raised portion  23 . In a preferred embodiment, arm portion  26  of each bracket  20  defines at least one aperture  28  therethrough so as to provide an anchoring point for frame  30 , as will be described in greater detail below. While the figures illustrate multiple mounting brackets  20  having a particular shape and configuration, persons having ordinary skill in the art will understand that fixture  10  can comprise a single mounting bracket  20  or any number of mounting brackets  20 , or that mounting bracket(s)  20  can have alternative shapes, all without departing from the novel scope of the present invention. 
     Referring again to the figures, it will be seen that in the embodiment illustrated in  FIGS. 1 and 1   a  mounting brackets  20  are illustrated as channel brackets extending lengthwise adjacent the perimeter  18  of mounting plate  12 . In this embodiment, the arm portions  26 , best shown in  FIG. 2 , of mounting brackets  20  extend from bracket  20  and define an opening  28 . Housing  30  defines openings  30   a  such that when housing  30  is placed in its operative position on mounting plate  12  opening  30   a  is adjacent opening  28  such that a fastener  70  can be inserted therethrough fastening housing  30  to mounting plate  12 . In a preferred embodiment, opening  28  includes means, such as a threaded nut, to lock fastener  70  thereby securing housing  30  to mounting plate  12 . Accordingly, when so secured mounting brackets  20  allow frame  30  to hang suspended from the mounting plate  12  separating frame  30  from the actual mounting surface. The suspension of frame  30  from mounting brackets  20  provides elastic cushioning to the frame  30  when it is physically impacted by an object or person; that is, arm portion  26  of mounting brackets  20  will flex under stress allowing appropriate movement of frame  30  such that the frame does not absorb the energy of such an impact. In other words, when impacted by a force, the frame  30  will slightly move relative the mounting surface relieving the stress of the impact while lessening damage to housing  30 . This enables the frame  30  to absorb part of the impact and makes the fixture  10  more durable. 
     As will be seen in the figures, frame  30 , in a preferred embodiment, comprises a substantially planar base  32  having a back side  33  and a front side  34 , a perimeter  35 , and at least one opening  36  through which light from the fixture emerges. While the illustrative embodiments show a single centrally located opening  36  it will be understood that fixture  10  can have any number of openings of any sizes or shapes without departing from the novel scope of the present invention. In  FIG. 2  base  32 , of the frame  30 , is shown in substantially parallel orientation with mounting plate  12 ; however, it will be understood that base  32  of the frame  30  can have alternate shapes or configurations without departing from the novel scope of the present invention. 
     As shown in  FIGS. 2 and 3 , the frame  30  comprises a plurality of second fasteners  37  extending from back side  33  of base  32 . The second fasteners  37  are positioned around the opening  36  and extend substantially perpendicularly away from base  32  of frame  30 . The purpose for secondary fasteners  37  will become apparent in the further description of these elements below. It will be seen in  FIGS. 2 and 3 , that frame  30  has is beveled at its border  38 . In the illustrative embodiment the border  38  angularly extends away from the perimeter  35  of the base  32  towards the location of mounting plate  12  when the frame  30  and mounting plate  12  are in operative cooperation. In a preferred embodiment, illustrated in  FIGS. 2-3 , border  38  includes an integrally formed flange  39  that is generally parallel to the surface of base  32 . It will be seen that flange  39  bends towards the perimeter  18  of the mounting plate  12  and creates an expansion gap  21  between mounting plate  12  and frame  30 . A discussion of the purpose for expansion gap  21  is included below. As shown in  FIG. 2 , when the fixture is assembled, flange  39  is substantially in the same plane as the mounting plate  12 , and is thus suitable for being placed generally flush against the mounting surface when fixture  10  is installed. As noted frame  30  and mounting plate  12  form a light fixture housing  19  having an interior cavity  29 . 
     As shown in  FIGS. 1 and 2 , fixture  10  has a substantially planar cover  40  suitable for spanning the one or more openings  36  located on the base  32  of frame  30 . In the illustrative embodiment cover  40  can lie adjacent back side  33  of base  32 , or in some embodiments cover  30  can be made integral with base  32  itself. As illustrated, cover  40  has a back side  42  and front side  44  and is made of a non-opaque medium suitable for allowing light to pass through the cover  40 . As will be understood by persons having skill in the art, cover  40  can be made of either transparent or translucent materials such as, for example, glass, reinforced glass, polycarbonate, fiberglass, plastic, injection molded polycarbonate or fiberglass reinforced plastic. Cover  40  can be made in various colors, or can have various designs, logos, images or other indicia formed thereon in order to create a decorative impression or for advertising or communication purposes. In addition, while the illustrated cover, shown in  FIGS. 1 and 2 , has a substantially flat rectangular orientation, it will be understood that the fixture  10  can include a cover  40  having alternative shapes, sizes or configurations without departing from the novel scope of the invention. It will be understood that cover  40  can be made to accommodate whatever shape light fixture housing  30  takes without departing from the novel scope of the present invention. 
     As shown most particularly in  FIGS. 1 and 2 , fixture  10  has a light source  50  disposed within interior cavity  29  of housing  19 . Light source  50  will be of a type suitable to emit light through cover  40  so as to provide illumination to areas proximate fixture  10 . It will be understood by persons having ordinary skill in the art that any type of light emitting device can be used to provide the lighting element of the present invention, light source  50  can, for example, be a fluorescent type fixture, an incandescent type fixture or an array of light emitting diodes (LEDs). With respect to LEDs, it is generally understood that such light elements have advantages over incandescent and fluorescent light fixtures. These advantages include: better energy efficiency; improved directional output, and enhanced damage-resistance. Persons having ordinary skill in the art will understand that the fixture  10  can feature other types of light sources  50 , besides, or in addition to, a LED device. In the illustrative embodiment the light source  50  has a substantially planar orientation and is positioned adjacent the back side  42  of the cover  40 . It will be understood that light source  50  can be made in various colors, sizes or shapes to suit any application. It will be understood that elements necessary to the workings of an electrical lamp, such as an electrical ballast  52  will be operatively connected to the light source  50  in a manner understood by persons having ordinary skill in the art. Electrical elements, such as ballast  52 , can be housed within the interior cavity  29  of the fixture  10 , or in alternative locations proximate the fixture  10 , all without departing from the novel scope of the present invention. 
     It will be seen that fixture  10 , shown in  FIGS. 1 and 2 , additionally has a retainer plate  60  disposed within the interior cavity  29  of the housing  19  and adjacent the light source  50 . As shown in  FIG. 2 , the retainer plate  40  can be fastened to the frame  30  by the second fasteners  37 , noted above, extending from the back side  33  of base  32  of frame  30 . The retainer plate  60  and second fasteners  37  are suitable for securing the light source  50  in place within the interior cavity  29  and can also be suitable for securing the cover  40  within the fixture. 
     As seen most particularly in  FIG. 2 , a plurality of fasteners  70  affixing frame  30 , at or about border  38 , to the one or more mounting brackets  20 , described above. In the present embodiment fasteners  37  extend through both the border  38  of the frame  30  and the aperture  28  in the arm  26  of the mounting bracket  20 . Fasteners  70  can be, for example, a nut or screw; bracket  20  can be fitted with an appropriate cooperative threading means, such as a bolt, to allow fastener  70  to be there attached. It will be understood that fastening, using clips or other means that will provide a secure connection between frame  30  and mounting plate  12 , known to persons having skill in the art can be utilized without departing from the novel scope of the present invention. 
     The present disclosure includes that which is contained in the appended claims, as well as that of the forgoing description. Although, this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example, and that numerous changes in the details of the elements, compositions and the combination of individual ingredients may be resorted to without departing from the spirit or scope of the invention.