Patent Abstract:
A warning light for attachment to a vehicle comprising a thermally conductive longitudinally extending base, a plurality of light head mount assemblies, a plurality of LED warning light assemblies, and a plurality of electronic control circuits. Said base has a pair of generally parallel longitudinal edges and a pair of ribs projecting perpendicularly from said base. Said light head mount assemblies comprise a bracket and a light head retention shoe. Said bracket has a generally planar bracket first portion and a generally planar bracket second portion oriented perpendicular to said first portion. Said light head shoe has a sole configured to engage said bracket first portion, a rib engaging portion, and a brace extending angularly therebetween. Said LED assemblies are mounted on said bracket second portion. Said dome has a main body portion, sidewalls configured to engage said edges, and end walls.

Full Description:
BACKGROUND OF THE DISCLOSURE 
     The present disclosure relates to warning lights, and more particularly to warning light assemblies for use with a motor vehicle. 
     Warning lights in the form of light bars mounted on emergency vehicles are well known in the art. Warning lights are utilized on many different types of vehicles to give visual indications of their presence during emergencies. Warning lights typically comprise an elongated base, a plurality of electronic components, and at least one lens portion. The elongated base may be provided in the form of an extrusion. 
     Warning lights are traditionally required by state and federal safety regulations to produce very bright light with specific color and emission patterns. As a result, the electronic components and warning light assemblies give off a great deal of heat. Warning light assemblies, particularly those using light emitting diodes (LEDs), are able to put out less light and can be damaged when operated at higher temperatures. 
     When used on emergency motor vehicles, warning lights are exposed to a wide range of environmental conditions. As dirt, water, and salt may corrode metal pars, fog the lenses, and destroy electronic components, warning lights must provide a weather-resistant barrier against the elements. 
     The modern trend is toward compact, low profile, self-contained warning light assemblies. Given the well-known issues of heat generation and protection from the elements, modern light bars must simultaneously provide a strong weather-resistant seal while providing an efficient pathway for heat generated within. U.S. Pat. Nos. 7,611,270 and 6,863,424, assigned to the assignee of the present disclosure are illustrative of warning light assemblies utilizing two different configurations to seal the warning light against the elements and provide an efficient path to direct heat away from the electronic components. 
     SUMMARY 
     According to aspects of the disclosure, a warning light for attachment to a vehicle comprises a thermally conductive longitudinally extending base, a plurality of mounting assemblies, a plurality of warning light assemblies, and at least one light-transmissive dome secured to the base. 
     The base has a pair of generally parallel longitudinal edges configured to engage the base and defines a pair of longitudinally extending light head shoe retention pockets adjacent to and oriented away from the edges. A pair of longitudinally extending ribs are spaced laterally inwardly of the retention pockets and project generally perpendicular from the base. The ribs terminate in a ridge and have a light head shoe retention lip projecting laterally toward the retention pocket at a point intermediate the base and the ridge. The light head shoe retention lip defines a retention channel oriented towards the base. 
     The plurality of mounting light assemblies generally comprise a plurality of brackets and a corresponding plurality of light head retention shoes. Each of the brackets are constructed of thermally conductive material, and have a generally planar bracket first portion in contact with the base and a generally planar bracket second portion to support a light generator. The bracket first portion is oriented generally perpendicular to the bracket second portion. A plurality of LEDs are mounted in thermally conductive contact to the bracket second portion. 
     Each of the plurality of light head retention shoes has a sole having a leading edge and toes configured to engage the retention pocket of the base and to maintain the bracket first portion in thermally conductive contact with the base. A rib engaging portion is located laterally opposite the foot. The rib engaging portion has a plurality of fingers configured to engage the distal ridge and a flexible retention member configured to reversibly engage the retention channel. A brace having a web and opposed sidewalls extends angularly between the rib engaging portion and the sole. The sidewalls project generally perpendicularly from the web and form a rigid structure. 
     In accordance with a further aspect of the disclosure, the light-transmissive dome has a generally planar main body portion oriented generally parallel to the base and longitudinally opposed inner and outer ends. Longitudinally extending sidewalls are contiguous with and extend generally perpendicularly from the main body portion, and terminate in a bottom edge. The main body portion defines a shallow longitudinally extending dome channel sized to receive a longitudinally extending panel. The outer end has an end wall contiguous with and extending generally perpendicularly from the main body portion, and terminates in a bottom edge. The end wall is oriented contiguous with and generally transverse to the sidewalls. The parallel longitudinal edges define a longitudinally extending dome-securing channel configured to receive the bottom edge of the longitudinally extending sidewalls and define an interior cavity. 
     In accordance with a further aspect of the disclosure, the longitudinally extending ribs define a center channel sized to receive at least one PC board and a plurality of arch-shaped bridges. Each of the bridges has laterally opposed pairs of feet. A snap fit connector extends away from the bridge. The snap fit connector is configured to reversibly mate with notch defined on at least one of the ribs. 
     The bridge also has a PC board retention member which comprises a cantilevered snap fit connector. A PC board retention snap works cooperatively with a nub. The nub is configured to engage one of a plurality of locator holes defined on longitudinally opposed ends of the control PC board to secure the control PC board within the center channel. 
     The configuration of the warning light in the current disclosure reduces the part count and the number of tools required for assembly. Additionally, the modular design of the disclosure gives greater flexibility in the lay out of the warning light. The light heads may be located anywhere along the base, since there are no restrictions or fixed points where the hardware must be located to secure the light heads to the base. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Aspects of the preferred embodiment will be described in reference to the Drawings, where like numerals reflect like elements: 
         FIG. 1  is a side view of one embodiment of the warning light of the present disclosure, with particular emphasis on a light head shoe, a bracket, and the rib and retention pocket of the base, all other components of the warning light are omitted for clarity; 
         FIG. 2  is a perspective cross-sectional view of one embodiment of the warning light of the disclosure, the cross section is depicted as intersecting the warning light intermediate sidewalls of one of the light head shoes; 
         FIG. 3  is a perspective view of the embodiment of the light head retention shoe and the bracket of  FIG. 2 ; 
         FIG. 4  shows a perspective view of one embodiment of the warning light; the generally concave light transmissive dome for a portion of the warning light is omitted for clarity, a mount to attach the warning light to a vehicle is also depicted; 
         FIG. 5  shows a rear view of the embodiment of the bracket depicted in  FIG. 2 ; 
         FIG. 6  shows an embodiment of the bracket configured for use with shoes disposed at longitudinal ends of the base; 
         FIG. 7  is a perspective view of one embodiment of the base having a bridge received in a center channel defined intermediate the ribs, the warning light mount of  FIG. 4  is also included; 
         FIG. 8  shows a perspective view of the underside of the light transmissive dome; 
         FIG. 9  shows a top plan view of the longitudinal ends of the base and the embodiment of the bracket depicted in  FIG. 6  interfacing with a longitudinal end of the base, all other components of the warning light are omitted for clarity; 
         FIG. 10  is a perspective view of the bridge depicted in  FIG. 7 , all other components of the warning light are omitted for clarity; 
         FIG. 11  shows a side view, partly in perspective, of one embodiment of an emergency warning light, the warning light mount depicted in  FIG. 4  is also included; 
         FIG. 12  shows a cross-sectional view of the emergency warning light of  FIG. 11 , the plurality of LED assemblies, mounting and control circuits have been omitted for clarity; 
         FIG. 13  is a cross-sectional view of one embodiment of the warning light with particular emphasis on the interface between one of the sidewalls and the longitudinal edge of the base, the plurality of LED assemblies, mounting and control circuits have been omitted for clarity; and 
         FIG. 14  is a cross-sectional view of one embodiment of the warning light with particular emphasis on the interface between the inner edge of the dome, the dome coupler and the wipe seal, the plurality of LED assemblies, mounting and control circuits have been omitted for clarity. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Embodiments of a warning light will now be described with reference to the Figures, wherein like numerals represent like parts throughout the  FIGS. 1-8 .  FIGS. 1 ,  2  and  7  depict a warning light  100  for attachment to a vehicle comprises a longitudinally extending base  102  constructed from a thermally conductive material. In one embodiment, the base  102  is an aluminum extrusion. 
     The base  102  has a generally parallel pair of longitudinal edges  104 . Laterally inwardly of the longitudinal edges  104 , the base  102  defines a pair of light head retention pockets  106 . The pocket  106  is defined along substantially the entire length of the base  102 . The pockets  106  are defined on the base  102  such that the pocket opens generally away from the nearest longitudinal edge  104  toward the center of the base. 
     As seen in  FIGS. 1 ,  2 ,  4  and  7 , a pair of ribs  108  extends substantially the entire length of the base  102 . The ribs  108  project from the base  102  intermediate the retention pockets  106 , and run longitudinally parallel with the retention pockets  106  and the edges  104 . The ribs  108  are equidistantly spaced from a central medial axis A-A ( FIG. 4 ) and prevent warping under the aerodynamic forces that may act on the base by providing structural support. 
     As best seen in  FIGS. 1 ,  2  and  7 , the ribs  108  project perpendicularly from the base  102  and terminate in a distal ridge  110 . In one embodiment, the ridge  110  is rounded and runs the length of the base  102 . A retention lip  112  projects laterally toward the retention pocket  106 . The retention lip  112  projects from the rib  108  at a point intermediate the base  102  and the ridge  110 . 
     The retention lip  112  has a ramped cross section having an increasing width, as best seen in the embodiment depicted in  FIGS. 1 and 2 . The retention lip  112  defines a retention channel  114  oriented toward the base  102  and having a generally concave cross-section. The retention lip  112  projects along the entire length of the rib  108 . 
     As best seen in  FIGS. 1 ,  2 ,  3  and  5 , the warning light also has a plurality of brackets  116  constructed from a thermally conductive material. Given its thermally conductive characteristics, superior workability and cost, in a preferred embodiment, the brackets  116  are constructed from sheets of aluminum. The brackets  116  have generally planar first and second portions  118  and  120 , respectively. The bracket  116  is configured such that the bracket second portion  120  is oriented generally perpendicular to the bracket first portion  118 . 
     As depicted in  FIG. 2 , a plurality of light emitting diodes (LEDs)  121  are mounted in thermally conductive contact to the bracket second portion  120 . In the embodiment of the warning light  100  depicted in  FIG. 2 , the LEDs  121  are mounted to a PC board  123  and are operatively mounted within a reflector  125 . Though a PC board  123  and reflector  125  are utilized in the embodiment shown, any of a multitude of configurations to mount the LEDs  121  to the bracket  116  may be utilized without departing from the scope of the disclosure. 
     In one embodiment depicted in  FIGS. 1 ,  2  and  5 , the bracket first portion  118  has a stepped configuration. In this embodiment, a ledge  122  extends perpendicularly between first and second generally planar steps  124  and  126 , respectively. The ledge  122  and first and second steps  124  and  126  define a plurality of engagement slots  128 . 
     In one embodiment best seen in  FIG. 5 , the first step  124  has a plurality of laterally projecting retention pocket engaging extensions  130 . The pocket engaging extensions  130  are constructed to engage the retention pocket  106  on the base  102  to ensure the brackets are secured against the base  102  in thermally conductive contact with the base  102 . 
     A plurality of light head retention shoes  132  correspond in number with the brackets  116 , and are best shown in  FIGS. 1-4 . The shoes  132  are configured to engage the brackets  116  to provide a secure connection between the brackets  116  and the base  102 . In one embodiment, the shoes  132  are molded plastic components. 
     Each shoe  132  has a sole  134  a leading edge  138 , and toes  140  configured to engage the bracket first portion  118 . The sole  134  is oriented generally parallel to the base  102 , and has a leading edge  138 . In one embodiment ( FIGS. 2 and 3 ), the sole  134  is generally planar. The planar configuration of the sole  134  is complementary to the bracket first portion  118  having a stepped configuration. The sole  134  is configured to maintain the first step  124  flat against the base  102 . A plurality of toes  140  project from the sole  134  along the leading edge  138 . The toes  140  are projections configured to engage the pocket  106  of the base  102 . The plurality of engagement slots  128  defined by the ledge and first and second steps are sized to receive the toes  140  adjacent the extensions  130 . 
     As seen in  FIGS. 2 and 3 , when the embodiment of the light head shoe  132  is correctly installed, the leading edge  138  abuts the bracket ledge  122 . The toes  140  of the shoe  132  project through the slots and engage the retention pocket  106 , while the leading edge  138  simultaneously provides a retentive force on the bracket first portion in a direction laterally toward the edge  104  of the base  102 . In the embodiment of the bracket  116  having laterally projecting pocket engaging extensions, the retentive force provided by the leading edge  138  additionally causes the pocket engaging extensions  130  to engage the retention pocket  106 . The leading edge thus acts in concert with the pocket engaging extensions  130  to provide an additional retentive force on the bracket  116  directed towards the base  102 . 
     In an embodiment of the light head shoe  132  depicted in  FIGS. 1-4 , the light head shoes  132  also have a rib engaging portion  142 . Specifically referring to  FIGS. 1 and 2 , the rib engaging portion  142  is configured laterally opposite the leading edge  138 , and comprises a plurality of engagement fingers  144  and a flexible retention member  146 . The engagement fingers  144  are designed to engage the ridge  110  of the ribs  108 . The engagement fingers  144  are configured to complement the shape of ridge  110 . For example, in the embodiment where the ridge  110  is rounded, the fingers have an arch-shaped cross section. 
     In the embodiment shown in  FIG. 3 , the flexible retention member  146  is disposed between the engagement fingers  144 . The flexible retention member  146  is a cantilevered snap fit connector. While the resilient retention member  146  comprises a u-shaped cantilevered snap fit connector in the embodiment depicted in  FIGS. 2 and 3 , other shaped configurations of cantilevered snap fit connectors may be employed without departing form the scope of the disclosure. 
     Referring specifically to  FIGS. 1 ,  2  and  3 , a brace  148  extends angularly between the sole  134  and the rib engaging portion  142 . The brace  148  has a web  150 , and a pair of opposed sidewalls  152  projecting generally perpendicularly from the web  150  forming a rigid structure. In one embodiment, the sidewalls  152  are oriented parallel to one another, and extend angularly between the sole  134  and the rib engaging portion  142 . As shown in  FIG. 1 , the engagement fingers  144  extend from the sidewalls  152 . 
     In addition to holding the brackets  116  against the base  102 , the shoes  132  also frictionally secure the brackets  116  longitudinally along the base  102  adjacent the edge  104 . To install the shoe  132  and bracket  116 , the bracket first portion  118  is first laid flat against the base  102  adjacent the edge  104 . The pocket engaging extensions  130  are installed in the pocket  106  and the toes  140  are inserted into the engagement slots  128  adjacent the pocket engaging extensions  130 . The toes  140  are inserted into the pocket  106 , and the leading edge  138  exerts a force on the bracket laterally toward the edge  104 . The shoe  132  is pivoted downwardly so that the engagement fingers  144  engage the ridge  110 , and the flexible retention member  146  snaps into the retention channel  114 . 
     A multitude of lighting configurations are possible as a result of the structural configuration of the base  102 , the brackets  116  and the shoes  132 . Since there are no fixed areas where hardware must be located to secure light heads to the base, different light patterns may be achieved using the same mounting apparatus and without perforating the base  102  for multiple mounting hardware configurations. Different LEDs and optical elements may also be used to change the pattern of the light emitted without changing the brackets  116  or the shoes  132 . 
       FIGS. 4 ,  6  and  9  show one embodiment of the bracket  116  specifically configured for use with light head shoes  132  disposed at longitudinal ends  153  of the base  102 . In this embodiment, the bracket  116  includes a third bracket portion  154 . The third bracket portion  154  is configured adjacent to and extends angularly away from the second bracket portion  120 , and oriented generally transverse to the bracket first portion  118 . 
     As shown in  FIGS. 4 ,  7  and  10 , the warning light  100  includes an arch-shaped bridge  156 . The bridge  156  extends between laterally opposed pairs of feet  158 . As best seen in  FIG. 7 , in this embodiment the ribs  108  define a center channel  160  laterally opposite the light head shoe retention lips  112 . The center channel  160  receives at least one PC board  162  configured to selectively energize the LEDs (not shown). 
     Referring specifically to  FIG. 10 , the bridge  156  has at least one snap fit connector  164  that extends axially away from the feet  158 . The snap fit connector  164  includes a laterally projecting protrusion  166  at each lateral end. As seen in  FIGS. 4 and 7 , the protrusion  166  reversibly mates with a longitudinal fixation notch  168  defined on the ribs  108 . 
     The bridge  156  has a PC board retention member  170  including a cantilevered snap  172  which cooperates with a nub  174  to secure the PC board  162  within the center channel  160 . A plurality of locator holes  176  are defined on longitudinally opposed ends of the PC board  162  and sized to receive the nub  174 . The cantilevered snap  172  has a barb  178 , which prevents the locator holes  176  from dislodging from the nub  174  to retain the PC board  162  in a fixed location relative to the base  102 . 
     In one embodiment depicted in  FIG. 10 , the feet  158  have laterally extending tabs  180  extending inwardly and outwardly. In this embodiment, the base  102  defines a pair of tracks  181  defined intermediate and running longitudinally parallel with the ribs  108  ( FIG. 7 ). The tracks  181  are configured to receive the laterally extending tabs  180  and secure the bridge  156  to the base  102 . 
     Referring to  FIGS. 8 , and  11 - 14 , a generally light transmissive dome  182  is operatively connectable to the base  102  to define an enclosure. In one embodiment, the dome  182  has a main body portion  184  oriented generally parallel to the base  102 . The main body portion  184  defines a longitudinally extending dome channel  186  which extends between longitudinally opposed outer and inner ends  188  and  190 , respectively ( FIG. 11 ) on top of the warning light. In one embodiment, the dome channel  186  spans a majority of the lateral width of the dome  182 . 
     A panel  187  is received in the dome channel  186 . In one embodiment, the panel  187  is opaque, and obscures views of the internal components of the warning light. The panel  187  may also act as a sunshade, to prevent radiant energy from the sun&#39;s rays from heating up the interior of the light bar. As disclosed, the panel  187  is secured to the dome  182  by a plurality of fasteners  189  extending through the dome to engage receptacles on the bridges  191  ( FIG. 10 ). The panel  187  is extruded aluminum, though a plurality of other suitable materials may be used. 
     As best seen in  FIGS. 11-13 , sidewalls  192  extend the length of the dome  182 , between the outer and inner ends of the dome  188  and  190 . The sidewalls  192  are contiguous with and extend generally perpendicular from the main body  184 , and terminate in a bottom edge  194 . As shown in  FIGS. 8 ,  12  and  13 , a bottom wall portion  196  projects generally perpendicularly inwardly from the sidewall  192 . In this embodiment, the bottom edge  194  is defined at the laterally inward most portion of the bottom wall  196 . 
     In an embodiment of the dome  182  depicted in  FIGS. 8 and 11 , an end wall  198  located at the first terminal end  188  projects generally perpendicularly away from the main body portion  184 . The end wall  198  terminates in a bottom edge  200  which includes fastener apertures  208 . The end wall  198  is oriented generally transverse to the sidewalls  192 , and the end wall  198  and end wall bottom edge  200  are contiguous with the sidewalls  192  and sidewall bottom edge  196 , respectively. 
     The dome  182  is configured to reversibly mate with the longitudinally extending base  102 . In one embodiment best seen in  FIGS. 12 and 13 , the longitudinal edge  104  of the base  102  defines a longitudinally extending dome-securing channel  204 , which runs the length of the base  102 . The sidewall bottom edges  194  are configured such that the dome-securing channel  204  receives the sidewall bottom edges  194 , securing the dome  182  to the base  102 . To secure the dome  182  to the base  102 , the sidewall bottom edges  194  at the inner end  190  are first inserted into the dome-securing channel  204 . Once the sidewall bottom edges  194  are introduced into the dome-securing channel  204 , the dome  182  slides longitudinally on the base  102  until the end wall bottom edge  200  abuts one of the longitudinal ends  153  of the base  102 . 
     In one embodiment shown in  FIG. 8 , the sidewall bottom edge  194  has an interrupted rail  202 , which projects away from the sidewall bottom edge  194 . The rail  202  is sized to fit in the dome-securing channel  204  and ensures a secure connection between the dome  182  and the base  102  along the edges  104 . The rail  202  is configured to reduce friction between the rail  202  and the dome-securing channel  204  during installation of the dome  182 . 
     As shown in  FIG. 13 , a lip  206  which projects downwardly away from the sidewall bottom edge  194  adjacent the rail  202  may also be provided. The lip  206  further ensures that the elements do not penetrate the interior of the warning light  100 . The lip  206  extends along the front and rear edges of the light bar  100  to direct moisture away from the channel  204 . 
     As best seen in  FIGS. 8 and 11 , a plurality of fasteners  205  are utilized to ensure a secure connection between the dome  182  and the base  102 . As best seen in  FIG. 8 , the end wall bottom edge  200  defines a plurality of fastener holes  208 . The fastener holes  208  are defined on the end wall bottom edge  200  such that they align with fastener receptacles  210  defined on the base  102  ( FIG. 12 ). 
     As shown in  FIGS. 4 ,  7  and  10 , the bridges  156  are configured to cooperate with fasteners  189  to secure the dome  182  and the panel  187  to the base. As best seen in  FIG. 10 , a plurality of fastener receptacles  191  project axially from the feet  158  of the arch shaped bridge  156 . The receptacles  191  are sized to receive the fasteners  189  and hold the main body portion  184  and the panel  187  against the base  102 . The receptacles  191  and fasteners  189  work in concert with the dome  182 , panel  187 , and base  102  to maintain the original shape of the warning light  100 , despite aerodynamic forces that act on warning lights when vehicles travel at high speeds. 
     As shown in  FIGS. 11 and 14 , the warning light  100  has two generally light transmissive domes  182 . The domes  182  are installed on the base  102  such that the inner longitudinal ends  190  of the dome are oriented toward one another. The inner longitudinal ends  190  of the domes  182  are received in a dome coupler  212  when the longitudinal fasteners are secured to the dome securing pockets  210 . 
     The dome coupler  212  has the same sectional configuration as the inner ends  190  of the dome  182 . As seen in  FIG. 14 , dome coupler  212  defines a general I-beam configuration when viewed in longitudinal section. The dome coupler  212  includes a wipe seal  214  which is configured to receive the inner ends  190  of the domes  182 . The wipe seal  214  ensures a secure, weather-resistant connection between the dome coupler  212  and the inner ends  190  of the domes  182 . 
     In this embodiment, the domes  182  and the dome coupler  212  are configured to provide a secure, weather-resistant connection with the base  102 , even if the length of the base  102  varies. The dome coupler  212  and wipe seal  214  ensure a weather-tight seal is created with the inner ends  190  of the domes  182 , even if the base  102  is longer than intended. 
     While a preferred embodiment has been set forth for purposes of illustration, the foregoing description should not be deemed a limitation of the invention herein. Accordingly, various modifications, adaptations and alternatives may occur to one skilled in the art without departing from the spirit of the invention and scope of the claimed coverage.

Technology Classification (CPC): 1