Patent Publication Number: US-7896517-B2

Title: Downward illumination assembly

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     Not Applicable 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates generally to a downward illumination assembly for directing light downward from the ceiling area of a room. 
     2. Description of the Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98 
     It&#39;s well known to mount downward illumination assemblies on ceiling panels. For example, U.S. Pat. No. 5,145,247 issued 8 Sep. 1992 to Robert Mandy, discloses a downward illumination assembly including a lamp housing having a closed upper end, an open lower end disposed axially opposite the closed upper end, and a tubular canister extending from around a periphery of the upper end to and defining the open lower end. Ceiling mount tabs extend radially outward from spaced positions around an outer surface of the canister to provide engagement surfaces for fasteners connecting the lamp housing to an upper surface of a ceiling panel. The downward illumination assembly of the Mandy &#39;247 patent may include a pair of fluorescent lamp tubes removably supported in respective lamp sockets supported within the lamp housing and a generally tubular trim bezel friction fit within the tubular canister and retained, in part, by spring clips supported on an inner surface of the canister. The downward illumination assembly disclosed in the Mandy &#39;247 patent also may include a side conduit fitting aligned with a through hole in the canister and supported on and extending radially outward from the canister to provide access for electrical wires to the lamp sockets. However, a downward illumination assembly constructed according to the Mandy &#39;247 patent is unable to allow for removal of a lamp socket or ballast without removing the lamp housing. 
     Also, U.S. Pat. No. 7,066,617 issued 27 Jun. 2006 to Terry, Dalton, and Brandon Mandy (the Mandy &#39;617 patent), discloses a downward illumination assembly that includes a lamp housing canister having a closed upper end and a generally cylindrical canister wall extending integrally downwardly from around a periphery of the upper end to an open lower end disposed axially opposite the closed upper end with the open lower end being positionable over and in concentric alignment with a circular opening in a ceiling panel. Ceiling mounts are carried by the canister wall to provide engagement surfaces for mounting the lamp housing over an opening in an elevator drop-ceiling panel. The downward illumination assembly of the Mandy &#39;617 patent includes a power supply module that is removably supported in an installed position on a side-mounted module receptacle tray of the housing. The power supply module carries two lamp sockets and ballasts that are electrically coupled to the lamp sockets. When the power supply module is in the installed position fluorescent lamps plugged into the two lamp sockets extend into the lamp housing canister through respective lamp openings in the canister wall and will, when illuminated, radiate light out the lower end of the lamp housing canister and through an opening in a drop ceiling panel that the housing is mounted on. The ballasts and sockets carried by the power supply module are serviceable by either lowering the elevator drop ceiling carrying the assembly or by gaining access to the space above the drop ceiling panel and below a top panel or roof of an elevator. Generally, access may be gained to this space by removing an emergency exit door in the top panel of the elevator. In either case, the lamp housing canister is generally left supported on the drop ceiling panel as whatever component requiring servicing is then serviced. However, the lamp sockets and ballasts may first be removed from the lamp housing canister along with the power supply module by unfastening and removing the power supply module and withdrawing the lamps radially outwardly through the lamp openings in the canister wall. However, a downward illumination assembly constructed according to the Mandy &#39;617 patent doesn&#39;t allow for removal of the power supply module or servicing of the ballasts and sockets without first having to either lower the ceiling panel carrying the assembly of gaining access to the approximate six inch deep space between the drop ceiling and roof of an elevator. 
     What would be desirable would be a downward illumination assembly that allows for removal of lamp socket and ballast without having to first lower a ceiling panel carrying the assembly or gaining access to a space between the ceiling panel and a roof disposed above the ceiling panel. 
     BRIEF SUMMARY OF THE DISCLOSURE 
     A downward illumination assembly is provided for directing light downward from the ceiling area of a room. The assembly includes a lamp housing having a housing wall extending downwardly to an open lower end configured to be positioned adjacent an opening in a ceiling panel. A power supply module is removably supported in an installed position on the housing and carries a lamp socket such that when the power supply module is in the installed position a lamp plugged into the lamp socket is disposed in a position to radiate light out the lower end of the lamp housing and through an opening in a ceiling panel that the housing is mounted on. The power supply module is configured to be removed interiorly of the lamp housing through the open lower end of the lamp housing. This allows the lamp socket and/or associated wiring to be serviced or replaced from a position below the ceiling panel and without having to remove the lamp housing from the ceiling panel or to disconnect and lower the ceiling panel or a portion of the ceiling panel from a supporting structure. 
     Also, a method is provided for servicing components housed in the power supply module of the downward illumination assembly when the assembly is carried by a ceiling panel. The method includes gaining access to an interior of the lamp housing through a lower opening of the lamp housing, removing the power supply module from its installed position interiorly of the lamp housing through the lower opening of the lamp housing, servicing a component carried by the power supply module, and returning the power supply module to its installed position on the lamp housing. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       These and other features and advantages will become apparent to those skilled in the art in connection with the following detailed description and drawings of one or more embodiments of the invention, in which: 
         FIG. 1  is a perspective view of a plurality of downward illumination assemblies constructed according to the invention and mounted on a drop ceiling panel in an elevator cab and with two side walls of the elevator having been removed for clarity; 
         FIG. 2  is a magnified perspective front view of one of the downward illumination assemblies of  FIG. 1  with a portion of the drop ceiling panel cut away to reveal more of the assembly; 
         FIG. 3  is perspective front-left end view of the downward illumination assembly of  FIG. 2 ; 
         FIG. 4  is perspective bottom-right end view of the downward illumination assembly of  FIG. 2 ; 
         FIG. 5  is a perspective bottom view of the downward illumination assembly of  FIG. 2  showing fluorescent bulbs being removed from the assembly; 
         FIG. 6  is a perspective bottom view of the downward illumination assembly of  FIG. 2  with the fluorescent bulbs having been removed and wing nut fasteners being removed to free a power supply module of the assembly for removal; 
         FIG. 7  is a perspective front-bottom view of the downward illumination assembly of  FIG. 2  with the power supply module having been slid from a module receptacle tray of the assembly through a module receptacle opening into a lamp housing of the assembly; 
         FIG. 8  is a perspective front-bottom view of the downward illumination assembly of  FIG. 2  with the power supply module having been drawn out of the lamp housing of the assembly into a position where components of the power supply module can be serviced or replaced; 
         FIG. 9  is a perspective top-left side view of the module receptacle tray of the downward illumination assembly of  FIG. 2  supported on the lamp housing of the assembly and with the power supply module of the assembly having been removed; 
         FIG. 10  is a perspective front-top-right side view of the power supply module removed from the downward illumination assembly of  FIG. 2 ; 
         FIG. 11  is a top view of the power supply module of  FIG. 10 ; 
         FIG. 12  is a perspective back-top-right side view of a module enclosure of the power supply module of  FIG. 10  adjacent the module receptacle tray of the downward illumination assembly of  FIG. 2  with a box cover panel of the enclosure shown removed from a box portion of the enclosure; 
         FIG. 13  is a perspective right end view of the power supply module of  FIG. 10 ; and 
         FIG. 14  is a perspective top view of the power supply module of  FIG. 10  with the box cover panel of the module enclosure having been removed to reveal components of the power supply module. 
     
    
    
     DETAILED DESCRIPTION OF INVENTION EMBODIMENT(S) 
     A downward illumination assembly for directing light downward from the ceiling area of a room is generally shown at  10  in the drawings. The assembly  10  may include a lamp housing  12  having a housing wall  14  extending downwardly to an open lower end  16  that is to be positioned adjacent and in general concentric alignment with an opening  18  in a ceiling panel  20  such as a drop ceiling panel  20  of an elevator  22 . The assembly  10  may also include a power supply module  24  that is removably supported in an installed position on the lamp housing  12 . The power supply module  24  may, in turn, carry two lamp sockets  26  in respective positions such that when the power supply module  24  is in the installed position, lamps  28  plugged into the lamp sockets  26  are disposed in respective positions within the lamp housing  12  to radiate light out the lower end  16  of the lamp housing  12  and through an opening  18  in a ceiling panel  20  that the housing  12  is mounted on. The power supply module  24  may be removable interiorly of the lamp housing  12  through the open lower end  16  of the lamp housing  12  to allow the lamp sockets and/or associated wiring to be serviced or replaced from a position below the ceiling panel  20  and without having to remove the lamp housing  12  from the ceiling panel  20  or to disconnect and lower the ceiling panel  20  or a portion of the ceiling panel  20  from a supporting structure. 
     As shown in  FIGS. 4-8 ,  10 ,  11 ,  13  and  14 , the lamp sockets  26  may be of the type that receive fluorescent lamps  28 , in which case the assembly  10  may also include one or more ballasts  30 . The ballasts  30  may be carried by the power supply module  24  and electrically coupled to the lamp sockets  26  as shown in  FIG. 14 . The ballasts  30  may thus be removable with the power supply module  24  from the housing  12 . As is well known, a ballast  30  provides the proper voltage to establish an arc between the two electrodes of a fluorescent lamp and regulates the electric current flowing through a fluorescent lamp to stabilize light output from the lamp. 
     As shown in  FIGS. 2-9 , the housing  12  may include a closed upper end  32  and the housing wall  14  may extend downwardly to the open lower end  16  from around a periphery of the closed upper end  32 . The closed housing upper end  32  may be generally circular in shape and the housing wall  14  may, consequently, be generally cylindrical in shape. The closed upper end  32  and generally cylindrical wall  14  of the housing  12  together define the general shape of a downwardly-opening canister. 
     As shown in  FIGS. 4-9 , the housing wall  14  may include a module receptacle opening  34  large enough to allow the power supply module  24  to pass completely through the module receptacle opening  34 . In the installed position the power supply module  24  may extend through the module receptacle opening  34  with a major portion of the power supply module  24  disposed exteriorly of the lamp housing  12 . Disposing a major portion of the power supply exteriorly of the lamp housing  12  minimizes the amount of lamp housing interior space taken up by the power supply module  24  and also limits any interference or disruption the power supply module  24  might cause with the dispersal of light from the lamps  28 . 
     As shown in  FIGS. 2-9  and  12 , the assembly  10  may further include a side-mounted module receptacle tray  36  carried by the housing wall  14  in alignment with the module receptacle opening  34 . The power supply module  24 , in the installed position, may be removably supported on the module receptacle tray  36  such that lamps  28  plugged into the lamp sockets  26  will extend into the lamp housing  12  and will, when illuminated, radiate light out the lower end  16  of the lamp housing  12  and through an opening  18  in a ceiling panel  20  that the housing  12  is mounted on. 
     As best shown in  FIGS. 9 and 12 , the module receptacle tray  36  includes a rectangular floor panel  38  and two rectangular tray side panels  40  that extend integrally upward from along opposite side edges of the floor panel  38  and normal to the floor panel  38 . The tray floor panels  38  and tray side panels  40  of the module receptacle tray  36  therefore form a channel of U-shaped cross-section sized to slidably receive the power supply module  24  into the installed position between the tray side panels  40  from a position within the lamp housing  12 . The U-shaped channel configuration also allows the power supply module  24  to be slid from the installed position into and through the interior of the lamp housing  12 . 
     As best shown in  FIGS. 2 ,  3 ,  7 ,  9 , and  12 , the module receptacle tray  36  may include two tray mounting tabs  42  that extend outwardly in opposite circumferential directions from the respective tray side panels  40 . Each tray mounting tab  42  may be fastened to the housing wall  14  by rivets  44 , as shown in the drawings, or by any other suitable means known in the art such as by spot welding the tray mounting tabs  42  to the housing wall  14  or fastening the tray mounting tabs  42  to the housing wall  14  using fasteners such as screws. 
     An inner end  46  of the power supply module  24  includes two module mounting tabs  48  positioned to engage the lamp housing wall  14  adjacent the module receptacle opening  34 . The module mounting tabs  48  may be positioned to engage or be engaged by respective module fasteners  50 . As is best shown in  FIGS. 6 and 12 , each module fastener  50  may include a threaded post  56  integrally extending from the tray mounting tabs  42  as shown in  FIG. 12 . When the module receptacle tray  36  is mounted on the lamp housing  12  the threaded posts  56  pass through corresponding openings in the lamp housing wall  14  adjacent opposite side edges of the module receptacle opening  34  as shown in  FIG. 6 . 
     As shown in  FIGS. 4-8  and  10 - 14 , each module mounting tab  48  may include a slot  58  shaped and positioned to receive one of the two threaded posts  56 . The module fasteners  50  may further include respective wing nuts  60  that thread onto the respective posts  56  and secure the module mounting tabs  48  to the lamp housing wall  14  once the power supply module  24  has been moved into the installed position. The wing nuts  60  allow manual threading and unthreaded from the posts  56  to free the power supply module  24  for removal and servicing and preclude the need to use a tool such as a wrench to attach and release the power supply module  24  in the installed position. 
     The power supply module  24  includes a generally rectilinear box-shaped module enclosure  62 . As best shown in  FIG. 12 , the module enclosure  62  includes a box portion  64  that includes a box bottom panel  66 , two opposite box side panels  68 , and two opposite box end panels  70 ,  72 . As shown in  FIGS. 2 ,  3 , and  10 - 13 , the module enclosure  62  also includes a box cover panel  74  that is removably securable to the box portion  64  of the power supply module  24  to cover a box opening  75  defined by the box side panels  68  and the box end panels  70 ,  72 . The sockets  26  are supported on and extend radially inwardly from a radially inner panel  70  of the two box end panels  70 ,  72 . 
     As shown in  FIGS. 3 ,  12 , and  14 , the module enclosure  62  may include an electrical power port  76  comprising one of two knockout apertures  78  formed in a radially outer box end panel  72  of the two box end panels  70 ,  72  of the module enclosure  62 . A current path defined by wires  82  carried by a flex conduit  84  may extend through the electrical power port  76 . The flex conduit  84  may be secured to the electrical power port  76  by a flex conduit connector  86 . The current path  80  may extend from the power supply module  24  to connect the sockets and ballast  30  into an electrical power circuit  88  along with a remote electrical power source  90 . The electrical power port  76  is disposed on the outer box end panel  72  of the module enclosure  62  instead of a box side panel of the module enclosure  62  so that the flex conduit  84  and flex conduit connector  86  won&#39;t impede the removal of the power supply module  24  through the housing  12  and so that the power supply module  24  can be drawn through the module receptacle opening  34  as the power supply module  24  is removed interiorly of the lamp housing  12 . 
     The module enclosure box cover panel  74  is shaped to be fastened over the box opening  75  in the module enclosure box portion  64  without impeding sliding motion of the power supply module  24  along the module receptacle tray  36 . More specifically, and as shown in FIGS.  3  and  10 - 13 , the module enclosure box cover panel  74  includes inner and outer box cover tabs  91 ,  92  extending downwardly from respective inner and outer edges of the module enclosure box cover panel  74  and normal to the module enclosure box cover panel  74 . The inner and outer box cover tabs  91 ,  92  each include respective tab through-holes aligned with corresponding end panel through-holes  96 ,  98  in the inner and outer box end panels  70 ,  72  of the module enclosure box portion  64 , respectively. Two screws  100 ,  102  extend through the respective tab through-holes in the inner and outer box cover tabs  91 ,  92  and are threadedly engaged in the end panel through-holes  96 ,  98  in the respective inner and outer box end panels  70 ,  72  of the module enclosure  62  box portion  64 . Because the inner and outer box cover tabs  91 ,  92  and screws  100 ,  102  are disposed on end surfaces of the power supply module  24  they provide no obstruction to the sliding motion of the power supply module  24  in the module receptacle tray  36 . 
     The module enclosure  62  includes ventilation holes  104  formed in the box side panels  68  and the box cover panel  74  of the module enclosure  62  to ensure that the ballast  30  doesn&#39;t overheat in any installation location, e.g., the space between a roof  106  and drop ceiling panel  20  of an elevator  22 . Heat rejection can otherwise be a problem in such an installation location because, as shown in  FIG. 1 , the roof  106  and drop ceiling panel  20  of an elevator are generally are only six inches apart. Although a fan  108  may be located in the drop ceiling  20  or on the roof  106  of an elevator  22  cab and may be positioned to circulate air through this ceiling space, such fans can be shut off by, for example, a key switch at a control station of the elevator  22  while the lamps  28  are still illuminated and drawing power through the ballast  22 . 
     In practice, a component housed in the power supply module  24  of the downward illumination assembly  10  can be serviced by first gaining access to an interior of the lamp housing  12  through the open lower end  16  of the lamp housing  12 . Where, as shown in  FIGS. 1 and 2 , the assembly  10  includes a covering such as a trim bezel  108  and/or cover lens extending over the open lower end  16  of the lamp housing  12 , gaining access to the interior of the lamp housing  12  may include removing the covering from the assembly  10 . 
     Any lamps plugged into the power supply module  24  are then unplugged from the module  24  and removed from the assembly  10  as shown in  FIG. 5 . The power supply module  24  is then removed from its installed position interiorly of the lamp housing  12  through the open lower end  16  of the lamp housing  12 . Where the assembly  10  includes module fasteners in the form of wing nuts  60  releasably fastening the power supply module  24  to corresponding threaded posts  56  extending from the housing wall  14 , removal of the power supply module  24  includes disengaging the module fasteners by unscrewing the two wing nuts  60  from the threaded posts  56  of the module fasteners as shown in  FIG. 6 . The power supply module  24  is then withdrawn by sliding the module radially inwardly through the module receptacle opening  34  of the lamp housing  12  as shown in  FIG. 7 , then out through the open lower end  16  of the lamp housing  12  as shown in  FIG. 8 . 
     Whatever power supply module component that requires servicing is then serviced and the power supply module  24  is returned to its installed position on the lamp housing  12 . Reinstallation of the power supply module  24  may include passing the power supply module  24  outer end-first through the open lower end  16  of the lamp housing  12 , through the module receptacle opening  34 , and sliding the power supply module  24  radially outwardly along the module receptacle tray  36  into the installed position. The module fasteners are then re-engaged by screwing the two wing nuts  60  onto the threaded posts  56  of the module fasteners. 
     This apparatus and method allow a lamp socket and/or associated wiring of a power supply module  24  of a downward illumination assembly  10  to be serviced or replaced from a position below the ceiling panel  20  that the assembly  10  is mounted on—and without having to remove the lamp housing  12  from the ceiling panel  20  or disconnect and lower the ceiling panel  20  or a portion of the ceiling panel  20  from a supporting structure. 
     This description, rather than describing limitations of an invention, only illustrates one embodiment of the invention recited in the claims. The language of this description is therefore exclusively descriptive and is non-limiting. Obviously, it&#39;s possible to modify this invention from what the description teaches. Within the scope of the claims, one may practice the invention other than as described above.