Patent Publication Number: US-2005128761-A1

Title: Turn signal light using light-emitting diodes as light sources

Description:
FIELD OF THE INVENTION  
      The present invention relates to a turn signal light, and more particularly to a turn signal light that uses light-emitting diodes as light sources.  
     BACKGROUND OF THE INVENTION  
      A turn signal light is provided to warn other drivers or pedestrians of a car going to turn or change its moving direction. Generally, the turn signal light for a vehicle uses a tungsten lamp as a light source. However, the conventional tungsten lamp tends to burn out due to high temperature or break due to shocks. And, light beams emitted from the tungsten lamp are too sharp. With advancements in the scientific field, light-emitting diode (LED) has been developed. An LED has the advantages of providing a radiated light source and moderate beams, and not tending to break due to shocks, and is therefore gradually adopted by consumers as a light source of the turn signal light. Nevertheless, light beams emitted from the LED are projected in the manner of bunched beams and thus provide a relatively small halo effect surrounding the turn signal light, which is not easily perceived by a driver of a coming car and therefore not safe for use.  
     SUMMARY OF THE INVENTION  
      A primary object of the present invention is to provide an improved turn signal light using light-emitting diodes as light sources, in which part of direct light beams emitted from light-emitting diodes are reflected and refracted to produce even better illuminating and warning effect.  
      To achieve the above and other objects, the turn signal light using light-emitting diodes as light sources according to the present invention mainly includes a backboard; a circuit board located in front of the backboard and provided at a front side with a plurality of light-emitting diodes to serve as light sources of the turn signal light; an intermediate board located in front of the circuit board and provided with a plurality of reflecting openings having reducing cross section to each enclose one light-emitting diode; and a lens located in front of the intermediate board and provided at an inner side with a plurality of raised areas. Part of initially direct light beams emitted from the light-emitting diodes are reflected at the reducing openings and refracted by the raised areas of the lens to provide diffused light and enhanced illuminating effect. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein  
       FIG. 1  is an exploded perspective view of a turn signal light using light-emitting diodes as light sources according to an embodiment of the present invention;  
       FIG. 2  is an assembled top perspective view of  FIG. 1 ;  
       FIG. 3  is a bottom perspective view of a lens of the turn signal light of  FIG. 1 ;  
       FIG. 4  is an assembled sectional view of  FIG. 2 ;  
       FIG. 5  is a sectional view showing the illuminating effect of the present invention;  
       FIG. 6  shows the use of the present invention on a motorcycle;  
       FIG. 7  shows the use of the present invention on a car; and  
       FIG. 8  is a bottom perspective view of an intermediate board in the turn signal light of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      Please refer to  FIG. 1  that is an exploded perspective view of a turn signal light  1  using light-emitting diodes as light sources according to the present invention. As shown, the turn signal light  1  mainly includes from bottom to top a backboard  10 , a circuit board  11 , an intermediate board  12 , and a lens  13 .  FIG. 2  is an assembled perspective view of  FIG. 1 .  
      The backboard  10  is a member having a flat rear side adapted for fitly attaching to any desired position on a vehicle, such as a motorcycle as shown in  FIG. 6 , or a car as shown in  FIG. 7 . Mounting holes  101  are provided on the backboard  10  at predetermined positions.  
      The circuit board  11  is provided on front and rear sides with a plurality of circuit elements (not shown), and at the front side with a plurality of light-emitting diodes  111 .  
      The intermediate board  12  is located between the circuit board  11  and the lens  13 , and provided with a plurality of separated openings  121  corresponding to the light-emitting diodes  111  on the circuit board  11 . Each of the openings  121  has a reducing cross section from outer to inner end thereof. Please refer to  FIG. 8 . An inner portion of each opening  121  located behind the intermediate board  12  forms a rearward protruded protective wall  123  to protect a corresponding light-emitting diode  111 . Spaces on a rear side of the intermediate board  12  between the protective walls  123  may still be fully utilized to accommodate electronic elements.  
      In the illustrated embodiment, each of the openings  121  has a hexagonal cross section. Through holes  122  are provided on the intermediate board  12  corresponding to the mounting holes  101  on the backboard  10 . When the intermediate board  12  is connected to the front side of the backboard  10  to locate in front of the circuit board  11 , the light-emitting diodes  111  are separately enclosed in inner surfaces of the openings  121  and the protective walls  123 . The intermediate board  12  may have a outer surface made of a reflecting material to enables the turn signal light of the present invention to have an enhanced illuminating effect.  
      Please refer to  FIGS. 2 and 3 . The lens  13  is provided at an inner side with a plurality of raised areas  131 . The raised areas  131  are not limited to any specific shape or type, and number. Mounting holes  132  are provided on the lens  13  corresponding to the mounting holes  101  on the backboard  10 .  
       FIG. 4  is an assembled sectional view of the turn signal light  1  of the present invention.  
      Please refer to  FIG. 5 . Light beams emitted from the light-emitting diodes  111  are first reflected at the inner wall surfaces of the openings  121  to intersect with one another. When the intermediate board  12  has reflecting outer surfaces, the reflection effect would be even better. The reflected light beams are then projected toward the inner side of the lens  13  and refracted by the raised areas  131  to shine in all directions.  
      The following are some advantages of the present invention:  
      1. The initially direct light beams emitted from the light-emitting diodes  111  enclosed in the openings  121  are reflected at the reflecting inner wall surfaces of the openings  121  to intersect with one another.  
      2. The openings  121  with reducing cross section and the protective walls  123  behind the intermediate board  12  provide good protection to the light-emitting diodes  111 , and the spaces between the protective walls  123  may still be fully utilized to accommodate electronic elements.  
      3. The raised areas  131  provided at the inner side of the lens  13  provide good refraction effect for the light beams emitted from the light-emitting diodes  111  to spread over an even wider range, enabling the turn signal light to be viewed by other drivers and pedestrians from widened viewing angles.  
      The present invention has been described with a preferred embodiment thereof and it is understood that many changes and modifications in the described embodiment can be carried out without departing from the scope and the spirit of the invention that is to be limited only by the appended claims.