Patent Document

BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The subject invention relates generally to lighting apparatus and more particularly to an improved step illumination fixture. 
     2. Description of Related Art 
     Various efforts have been made to improve lighting fixtures for illumination of steps in a staircase. One such effort is evidenced by U.S. Pat. No. 5,918,962 assigned to the assignee of the present application and entitled Dual Step Light and Indicator Apparatus. Such efforts have typically employed an extrusion having step and riser plate portions and electrically activated lighting devices located in the extrusion. Such lighting apparatus finds typical application in darkened theatre settings where it is desired to light the descending aisleway for patrons. 
     SUMMARY OF THE INVENTION 
     The subject invention relates to a step lighting apparatus which employs an ambient light reflective strip to alert users to the location of step edges in darkened or low light environments. Apparatus according to the invention may be conveniently used in conjunction with seat-mounted lights to provide a theatre step light fixture with no electrically activated lighting devices. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A preferred embodiment of the just-summarized invention will now be described in detail in conjunction with the drawings, of which: 
     FIG. 1 is a perspective view of a lighting apparatus according to the preferred embodiment of the invention; 
     FIG. 2 is a cross-section taken at  2 — 2  of FIG. 1; 
     FIG. 3 is an enlarged view of a portion of FIG. 2; 
     FIG. 4 is a perspective view illustrating one application of the preferred embodiment; 
     FIG. 5 is a front view of a beacon lamp unit as used in FIG. 4; and 
     FIGS. 6 and 7 are perspective views illustrating a preferred beacon lamp. 
     FIG. 8 is a perspective view illustrating a typical theatre stairway illumination pattern. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The preferred lighting apparatus is illustrated in FIGS. 1-3. As shown, the apparatus includes a horizontal step plate portion  13  and a vertical riser plate portion  15 . The step plate portion  13  includes a flat undersurface  17 , which typically abuts the horizontal surface of a step, while the riser plate portion  15  includes a flat vertical undersurface  19  which typically mounts against the vertical riser portion of a step. The particular embodiment shown further includes respective carpet insert slots  21 ,  23 . A number of ribs  25 ,  27 ,  29 ,  31  are formed between the inner surfaces  15 ,  17  and the outer surface  33  of the apparatus, which includes a horizontal or “tread” portion  35  and outer riser surface  37 . 
     As further illustrated, a rounded nose portion  38  includes a light reflective layer  39 , which forms a continuous outer surface with surfaces  35  and  37 . In the preferred embodiment, reflective layer  39  is applied by coextrusion with the remainder of the structure. In this connection, layer  39  preferably comprises a light gray polyvinyl chloride (PVC) strip coextruded with a black or other dark PVC material to form the entire unit  11 . The dark PVC may comprise 0.075 inch thick GEON C9000 (shore) black PVC plastic, while layer  39  comprises PVC material #291 as available from A&amp;B Plastics, Yakima, Wash. 
     It has been discovered that when units  11  are disposed on each of the noses of a succession of stairs, the light gray coextruded strip reflects sufficient ambient light to alert users as to the location of the edges of the step without requiring the use of electrically activated light sources within the unit  11 . Such light sources could of course still be employed, if desired. 
     Lighting apparatus according to the preferred embodiment may advantageously be used in conjunction with seat-mounted lamps  111 , as shown in FIG.  4 . The seat-mounted lamps  111  may be so-called beacon lamps as shown in FIG.  5 . Various constructions for beacon lamps are described in pending U.S. patent application Ser. No. 09/175,644 entitled Seat Mounted Aisle Step Light assigned to the assignee of this application and incorporated herein by reference. The particular beacon lamp embodiment shown in FIG. 5 includes a hemispherical lens  115 , a circular housing  113  and a lamp holder shield  117 . The particular embodiment of FIGS. 4 and 5 receives power via a feedwire  121  behind a wireway  119 . Various other ways of providing power to lamps, e.g. LED&#39;s, located beneath the shield portion of lampholder shield  117  may be provided. 
     An alternate and presently preferred beacon lamp  211  is illustrated in FIGS. 6 and 7. The lamp  211  includes a hemispherical lens  215 , the upper half  216  of which is rendered opaque by suitable coating. A housing  213  has a lampshield mounting component  214  attached thereto, e.g. welding. The component  214  includes a mounting pad  216  to which a lampholder shield  217  is attached, e.g. by screws inserted through pairs of holes  220 ,  222 . The lampshield  217  includes a mirrored undersurface  218 . 
     The component  214  may be formed of bendable metal such that the pad  214  can be bent to a desired angle to adjust or aim the light pattern provided by four LEDs  224  mounted in the lampholder shield  217  and powered via lead wires  226 . 
     As may be appreciated, the lampholder shield  217  directs illumination in a manner that illuminates the side of an aisleway. An illustrative lighting pattern is shown in FIG. 8, wherein beacon lamps  211  employing four amber LEDs  224  are used on one side of an aisleway with 36″ wide steps, a 6″ riser and 40″ pitch. The decimal numbers represent light distribution in foot candles with an average of 0.20 foot candles. 
     Light distributions such as shown in FIG. 8 typically will not clearly illuminate the edges of steps down the aisleway. The obscurity of the edge of the steps is particularly pronounced with LED light sources because the light is monochromatic and does not produce a great deal of contrast. Provision of step-mounted fixtures such as shown in FIGS. 1-3 provide a means of capturing and reflecting low level ambient light to provide clear demarcation of the step edges. The effect created is particularly striking and surprising to the observer. Thus, in a lighting system such as shown in FIG. 4, respective reflective layers  39  of the units  11  respond to relatively low-intensity or low-level ambient light generated by the beacon lamps  111  to render the strips  39  visible in the dark to persons traveling the staircase. 
     From the above description, those skilled in the art will appreciate that various adaptations and modifications of the just-described preferred embodiments can be configured without departing from the scope and spirit of the invention. Therefore, it is to be understood that within the scope of the appended claims, the invention may be practiced other than as specifically described herein.

Technology Category: 2