Abstract:
A perimeter-of-sign warning system is provided having a number of novel features. The provided system is defined by a warning flasher that encompasses the perimeter of a road sign. Its enclosure has provisions for mounting the sign, and a cross member provides additional support to the sign. Furthermore, the enclosure maintains perpendicularity between the face of the sign and the light output from the warning flasher, regardless of the orientation of the sign. The system also allows airflow through it, thus minimizing possible misalignment due to wind. Tamperproof hardware and plexiglas/Lexan panels provide protection against unauthorized access and vandalism. The warning flasher incorporates maintenance free solid-state light emitting diodes into its design. Its ‘light chaser’ flash pattern is designed to more effectively draw attention to the road sign to which it is associated.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     Not Applicable  
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT  
       [0002]     Not Applicable  
       REFERENCE TO SEQUENTIAL LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX  
       [0003]     Not Applicable  
       BACKGROUND OF THE INVENTION  
       [0004]     1. Field of the Invention  
         [0005]     This application relates to warning flasher systems—in particular to warning flashers associated with road signs. From this point forward, the term ‘road sign’ shall refer to any regulatory, warning or guide sign that is used for traffic control.  
         [0006]     2. Background Art  
         [0007]     Warning flashers have long been used to complement road signs. These flashers typically consist of one or more round flashing beacons located either above or below the sign. In some installations, beacons are located above and below the sign. Older designs coupled an incandescent lamp with a diffracting lens, while most current designs incorporate solid-state lamps [Light Emitting Diodes [LEDs]].  
         [0008]     In recent years, Light Emitting Diodes have become brighter, more robust and less expensive. These technological advances have improved the reliability and visibility of the warning beacon—and have opened the door for new warning flasher designs. Some new designs incorporate flashers into the road signs themselves.  
         [0009]     One design option positions warning flasher elements on the background of a road sign. Another option incorporates individual LEDs into the border of the sign—one LED element at each corner of the sign.  
         [0010]     There is an inherent weakness to both of these design options—the amount of space available on the face of the sign for the warning flasher is limited. This limitation results in the use of smaller flasher elements, thus reducing the effectiveness of such elements.  
         [0011]     The goal for any warning flasher system is to provide effective warning to approaching traffic. Regulatory agencies&#39; response to increased traffic volume, speed and driver distractions has been to mandate the use of larger—and in some cases more—warning flashers. Where 6- and 8-inch beacons were once used, 12-inch beacons are now specified. In locations where single beacons were typically used, now dual flashers are installed.  
         [0012]     To some extent, the incorporated flasher design options detailed above represent a step backward. While the agency focus has been on larger beacons with increased visibility, these designs—with smaller flasher elements—ultimately provide less visibility.  
       SUMMARY OF THE INVENTION  
       [0013]     The warning system embodiment of the present invention contains a number of novel features.  
         [0014]     In the preferred embodiment of this design, the warning flasher is independent of, but borders the road sign to which it is associated. By moving the flasher system off of the face of the sign, there is no limitation on the size of the flasher. A larger area can thus be dedicated to the warning system—without compromising the effectiveness of the sign itself.  
         [0015]     Additionally, the preferred embodiment incorporates a mounting bracket for the road sign. With this feature, homogeneity is maintained between the sign and the warning system. The chance for misalignment is eliminated—as the light output from the warning system remains perpendicular to the face of the sign, regardless of the sign&#39;s orientation.  
         [0016]     The preferred embodiment also provides support to the road sign to which it is associated. In standard installations, these signs are exposed to abuse—vandalism, wind, weather, etc. The conventional [two point] mounting system for such signs does little to prevent damage from such abuse. By providing cross support to the sign, the preferred embodiment minimizes these effects. Furthermore, air slots between the sign and the warning system enclosure prevent the system from possible misalignment due to wind gusts.  
         [0017]     Additionally, the system incorporates independently controlled solid-state light banks into its design. The system can thus provide a variety of flasher output patterns.  
         [0018]     The preferred embodiment of this invention employs a ‘light chaser’ pattern—each block on each light panel turns on and off sequentially. This pattern is designed to more effectively draw attention to the road sign to which it is associated. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]      FIG. 1A  is a front view of the perimeter of sign warning system—including a representative road sign—made in accordance with the present invention;  
         [0020]      FIG. 1B  is a close-up side view of section A-A′ of the embodiment in  FIG. 1A ;  
         [0021]      FIG. 1C  is a close-up side view of section B-B′ of the embodiment in  FIG. 1A ;  
         [0022]      FIG. 2  is an exploded front view of the system—less road sign and gaskets;  
         [0023]      FIG. 3  is a back view of the warning system—less road sign;  
         [0024]      FIG. 4A  is a cutaway side view of a typical installation for the warning system;  
         [0025]      FIG. 4B  is a view from the top of the installation shown in  FIG. 4A ;  
         [0026]      FIG. 5A  is the front view of the light panel sub assembly;  
         [0027]      FIG. 5B  is a side view of the light panel sub assembly illustrated in  FIG. 5A ;  
         [0028]      FIG. 5C  is a close-up side view of section C-C′ of the light panel sub assembly shown in  FIG. 5B ;  
         [0029]      FIG. 6A  is the front view of the solid-state light panel;  
         [0030]      FIG. 6B  is a side view of the solid-state light panel shown in  FIG. 6A ;  
         [0031]      FIG. 7  is the front view of the perimeter of sign warning system—with representative road sign—showing a stop action view of the light chaser flasher scheme;  
         [0032]      FIG. 8A  represents a general starting position for the warning flasher elements;  
         [0033]      FIG. 8B  represents the flasher element position directly following that in  FIG. 8A ;  
         [0034]      FIG. 8C  shows the transition from light block  9  back to light block  1 .  
         [0035]      FIG. 9  is a representative ‘light chaser’ circuit.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0036]     The Perimeter of Sign Warning System  1  shown in  FIGS. 1A, 1B , and  1 C represents a preferred embodiment of the invention. The warning system  1  consists of a stainless steel enclosure  3 , to which four light panel sub assemblies  4 , four service panels  5 , and a [representative] road sign  2 , are attached. The light panel sub assemblies  4  and service panels  5  are attached to the stainless steel enclosure  3  with tamperproof stainless steel screws  10 . Gaskets  9  and  37  provide a weatherproof seal between the light panel sub assemblies  4 , the service panels  5 , and the stainless steel enclosure  3 . Although stainless steel is specified, the enclosure  3 —and panels  4  and  5 —may be constructed using other materials, including nonferrous metals, fiberglass, plastic, composites, and other grades of steel.  
         [0037]     The inner perimeter  6  of the stainless steel enclosure  3  is sized so that there is a uniform gap  7  between the enclosure  3  and the road sign  2 . This gap  7  allows for airflow through the warning system  1 , so that misalignment due to wind gusts is minimized. The road sign  2  is secured to the stainless steel enclosure  3  with stainless steel hardware  8 .  
         [0038]     An exploded view of the warning system  1  is shown in  FIG. 2 —less road sign  2  and gaskets  9  and  37  shown in  FIGS. 1A, 1B , and  1 C. The light panel sub assemblies  4 , and service panels  5  are mounted to the stainless steel enclosure  3  with a total of sixty-four (64) tamperproof stainless steel screws  10 . Each light panel sub assembly  4  uses ten screws  10 , while each service panel  5  requires six of these screws  10 . The enclosure  3  is equipped with sixty-four (64) threaded inserts  15  to ensure proper engagement of the tamperproof stainless steel screws  10 . The service panels  5  allow access to the interior of the enclosure  3  for mounting the warning system, and for maintenance.  
         [0039]     Each light panel sub assembly  4  contains solid-state light panels  14  and a plexiglas/Lexan shield  13 . These are secured to the light panel sub assembly  4  with tamperproof stainless steel screws  11  and  12 . A slot  38  cut in the front of the light panel sub assembly  4  allows light through from the solid state light panels  14 .  
         [0040]     The preferred embodiment of the stainless steel enclosure  3  also includes a sign support  16 . This stainless steel cross member has holes  17  for mounting the road sign  2  in  FIG. 1A . The sign support  16  provides support to each corner of the road sign  2 , and also allows the warning system  1  to maintain near perpendicularity between the face of the road sign  2  and the illuminated output from light panel sub assemblies  4 , as illustrated in  FIG. 1A .  
         [0041]     The back view of the enclosure  3  is shown in  FIG. 3 , and a typical warning system installation is shown in  FIGS. 4A and 4B . Mounting holes  18  on the back of the enclosure  3  allow the warning system  1  to be mounted to a round pole  19  with stainless steel U-bolts  20 . The stainless steel enclosure  3  has provisions for two U-bolts  20 —one each at the top and bottom. Separate mounting brackets  21  assure consistent clamping around the pole  19 . Once assembled to the round pole  19 , tamperproof stainless steel hardware  10  and service panels  5  on the front of the warning system  1  protect the U-bolts  20 , and associated hardware from unauthorized access. Gasket  37  provides a weatherproof seal between the enclosure  3  and the service panel  5 .  
         [0042]     The light panel sub assembly  4  is detailed in  FIGS. 5A, 5B , and  5 C. This sub assembly consists of a stainless steel panel  39 , gasket  23 , plexiglas/Lexan shield  13 , three solid state light panels  14 , and tamperproof stainless steel mounting hardware  11 ,  12 ,  24 ,  26 ,  41 ,  42 . On each light panel sub assembly, the gasket  23  is sandwiched between the plexiglas/Lexan shield  13  and the stainless steel panel  39 . These are secured with tamperproof stainless steel screws  11  and  12 , stainless steel nuts  24 ,  41  and washers  42  prior to assembling the solid-state light panels  14  to the light panel sub assembly  4 . The twelve (12) tamperproof stainless steel screws  11  also support plastic spacers  25  and the solid-state light panels  14 , with stainless steel nuts  26 .  
         [0043]     Plastic spacers  25  maintain a uniform distance between the solid state LED light panel  14  and the plexiglas/ Lexan shield  13 . The stainless steel panel  39  contains a slot  38  that lets through light from the solid state LED light panel  14  via the plexiglas/Lexan shield  13 .  
         [0044]     Each light panel sub assembly  4  attaches to the enclosure  3  in  FIG. 2  through holes  22 .  
         [0045]     The solid-state light panel  14  in  FIGS. 6A and 6B  consists of a printed circuit board  30 , ten terminal blocks  29 , and forty-five (45) discrete Light Emitting Diode [LED] elements  27 . The LED elements  27  are positioned away from the printed circuit board  30  with plastic spacers  28 . These plastic spacers  28  allow for adjustment/alignment of each LED element  27 , and prevent overheating of the LED elements  27  during soldering.  
         [0046]     Each solid-state light panel  14  has four (4) mounting holes  31 .  
         [0047]     The printed circuit board  30  has a dark solder mask  33  over the entire top of the board. The solder mask  33  provides a contrasting background for the LED elements  27  to allow for better visibility, particularly during daylight hours. To further improve daytime visibility, hoods may be mounted on the enclosure.  
         [0048]     On the printed circuit board  30 , the LED elements  27  comprise three equal-sized independent light blocks  32 . Each light block  32  consists of fifteen (15) LED elements  27 . As illustrated earlier in  FIG. 5B , each light panel sub assembly  4  utilizes three solid-state LED light panels  14 . This results in nine independent light blocks  32  per light panel sub assembly  4 . The number and size of the light blocks  32 —and the number and color of LED elements  27  contained therein—may be adjusted based on user requirements.  
         [0049]     While several flash options may be achieved, the preferred embodiment of the warning system  1  employs a ‘light chaser’ flasher pattern around the road sign  2 , as shown in  FIG. 7 . Select light blocks  34  are activated at specific intervals. When the warning system  1  is active, the same light block  34  position is illuminated on each light panel sub assembly  4 . When this position shuts off, the position directly next to that one turns on.  
         [0050]     This pattern is further detailed in  FIGS. 8A, 8B , and  8 C. As illustrated, if the flashing pattern begins on light block  35 , then when this block turns off, the light block  36  right next to it turns on. When the ninth light block  40  is reached, the pattern continues with first light block  43 , and so on.  
         [0051]     A representative ‘light chaser’ circuit is shown in  FIG. 9 . This circuit has been designed for 12 volt DC operation, so it suitable for solar and/or battery installations. It can also be powered by line current [AC] if it properly stepped down to 12 volts DC.  
         [0052]     An oscillator circuit is comprised of an integrated circuit multivibrator [i.e. CD4047]  44 , capacitor  45 , resistor  46 , and potentiometer  47 . With the pin connections as shown, the multivibrator  44  is configured as a free-running oscillator whose frequency is defined by capacitor  45  and resistor  46 , and is fine-tuned by potentiometer  47 .  
         [0053]     For an output frequency of 5 hertz, capacitor  45  has a value of 0.56 uF, resistor  46  has a value of 51K ohms, and the potentiometer  47  has a maximum value of 100K ohms.  
         [0054]     The output from the pin  11  [Pin 11 ] of the integrated circuit multivibrator  44  is fed into pin  14  [Pin 14 ] of a decade counter integrated circuit [i.e. CD4017]  48 . With the pin connections shown, the decade counter integrated circuit  48  is configured as a 1-to-9 counter circuit with reset. This circuit has nine outputs  49 ,  50 ,  51 ,  52 ,  53 ,  54 ,  55 ,  56 ,  57 .  
         [0055]     When the circuit is turned on, one of these outputs will start in the ‘on’ position—the other eight outputs will be ‘off’. With each pulse from pin  11  [Pin 11 ] of the multivibrator  44 , these outputs will increment. As an example, if output  51  was ‘on’ with the current oscillator pulse, then with the next pulse output  51  will turn ‘off’ and output  52  will turn ‘on’. Once output  57  is reached, the 1-to-9 counter recycles, so on the next oscillator pulse it returns to output  49 .  
         [0056]     The outputs  49 ,  50 ,  51 ,  52 ,  53 ,  54 ,  55 ,  56 ,  57  are subsequently used to drive solid-state relays which, in turn, are used to control the individual light blocks shown earlier in  FIG. 7  and  FIGS. 8A, 8B , and  8 C  
         [0057]     Having now fully set forth the preferred embodiments and certain modifications of the concept underlying the present invention, various other embodiments as well as certain variations and modifications to the embodiment herein shown and described will obviously occur to those skilled in the art upon becoming familiar with said underlying concept. It is to be understood therefore, that the invention may be practiced otherwise than specifically set forth in the appended claims, and that various changes may be made without departing from the spirit and scope of the invention.