Abstract:
An LED lamp assembly includes LED circuit boards having LEDs as light sources, and concave parabolic lens surfaces as light condensing surface to replace convex lens surfaces having been conventionally used for LED light sources as well as to allow the LED circuit boards to be deposited at sites where is so well air ventilation that heat generated thereby is dissipated rapidly to ensure good heat dissipation for the LED circuit boards; and a reflective LED searchlight comprises the LED lamp assembly as an essential component and features a good heat dissipation for its LED circuit boards.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Present Invention 
         [0002]    The present invention relates to searchlights, and more particularly to a reflective LED searchlight. 
         [0003]    2. Description of Related Art 
         [0004]    As shown in  FIG. 1 , a conventional searchlight 11 is a versatile searchlight supporting vertical and horizontal adjustment of its illumination angle. The searchlight 11 includes a lamp holder housing 12, a supporting seat 13 pivotally supporting the lamp holder housing 12 from below, and a lamp assembly 15 pivotally installed in the lamp holder housing 12. 
         [0005]    Therein, the lamp assembly 15 is configured to tilt up and down with respect to the lamp holder housing 12 so as to change the illumination angle of the searchlight 11 vertically. The lamp holder housing 12 and the lamp assembly 15 can rotate horizontally in both directions with respect to the supporting seat 13, so as to change the illumination angle of the searchlight 11 horizontally. 
         [0006]    As shown in  FIG. 1  and  FIG. 2 , the lamp assembly 15 uses LEDs as light sources, and has a condensing lens 16 and an LED circuit board 18. The condensing lens 16 has a plurality of convex lens surfaces 17, and the LED circuit board 18 has a plurality of LEDs 19 that are quantitatively corresponding to the convex lens surfaces 17 of the condensing lens 16. When assembled, the condensing lens 16 is located in front of the LED circuit board 18, so that the LEDs 19 of the LED circuit board 18 are located at the focuses of the convex lens surfaces 17. 
         [0007]    When the searchlight 11 is turned on, the LEDs 19 of the lamp assembly 15 emit light, the light is then condensed by the convex lens surfaces 17 of the condensing lens 16, and projected as parallel beams far in front. 
         [0008]    The lamp assembly 15, nevertheless, has its weakness. Since the LEDs 19 of the LED circuit board 18 are sealed in the narrow space defined by the convex lens surfaces 17 of the condensing lens 16, the heat generated from the LEDs 19 if lighted is hardly dissipated, and this may lead to overheat and failure of the LED circuit board 18 of the lamp assembly 15. 
       SUMMARY OF THE INVENTION 
       [0009]    In view of this, it is an object of the invention to provide an LED lamp assembly, which at least comprises concave parabolic lens surfaces to replace convex lens surfaces having been conventionally used for LED light sources for a long time, and LED circuit boards containing a plurality of LEDs for illumination and each LED located at its corresponding focus of the concave parabolic lens surfaces; and more particularly, it is a specific configuration of the LED lamp assembly which allows the LED circuit boards to be deposited at sites where is so well air ventilation that heat generated thereby can be dissipated rapidly, so as to ensure good heat dissipation for the LED circuit boards, and in turn ensure good function over long-term use. 
         [0010]    It is another object of the invention to provide an LED lamp assembly comprising: 
         [0000]    a lamp casing, containing therein a recess whose upper edge portion and lower edge portion are each provided with a plurality of clamping blocks;
 
two LED circuit boards, each provided with a plurality of LEDs, wherein one of the LED circuit board is fixed by the clamping block at the upper edge portion of the recess of the lamp casing, and the other LED circuit board is fixed by the clamping block at the lower edge portion of the recess of the lamp casing;
 
a reflective lens, being a concave parabolic lens surface and having at least one set of double parabolic lens units, wherein each said set of double parabolic lens unit includes a first parabolic lens surface and a second parabolic lens surface integrated as a unity, and each said set of double parabolic lens unit has a slit located at a focus of each of the first parabolic lens surface and the second parabolic lens surface, so that after assembled, each said LED of the LED circuit boards is exposed at one said slit at the corresponding double parabolic lens unit;
 
a lens frame, having a lens to close the recess of the lamp casing; and
 
an outer frame, enclosing to the lens of the lens frame as well as allowing the lens frame and the outer frame being fixed to the lamp casing together.
 
         [0011]    It is still another object of the invention to provide an LED lamp assembly comprising a lamp casing which has its top and/or bottom provided with plural heat-dissipating ribs. 
         [0012]    It is another primary object of the invention to provide a reflective LED searchlight using the disclosed LED lamp assembly as an essential component of light source. 
         [0013]    The disclosed LED lamp assembly and a reflective LED searchlight using the LED lamp assembly have the following advantages: 
         [0000]    1. The concave parabolic lens surfaces condense the light embittered by the LED light sources into parallel LED light beams that can be projected or emitted far in front; and
 
2. The lens frame protects the LED circuit boards from moisture and the LED circuit boards are provided with better heat dissipation, so the lamp assembly is durable for long-term use.
 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is a schematic drawing of a conventional searchlight. 
           [0015]      FIG. 2  is a perspective view of a lamp assembly used in the searchlight of  FIG. 1 . 
           [0016]      FIG. 3  is a cut-away perspective view of a reflective LED searchlight of the present invention. 
           [0017]      FIG. 4  is a schematic drawing of the reflective LED searchlight of the present invention. 
           [0018]      FIG. 5  is a perspective view of a lamp assembly used in the searchlight of  FIG. 4 . 
           [0019]      FIG. 6  is another perspective view of the lamp assembly of  FIG. 5  taken from a different viewpoint. 
           [0020]      FIG. 7  is a cross-sectional view of the lamp assembly of  FIG. 5 . 
           [0021]      FIG. 8  is an exploded view of the lamp assembly of  FIG. 5 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0022]    Referring to  FIG. 3  and  FIG. 4 , according to the present invention, a reflective LED searchlight  10  (hereinafter referred to as the LED searchlight  10 ) is a versatile searchlight with its illumination angle vertically and horizontally adjustable. 
         [0023]    The LED searchlight  10  comprises a lamp holder housing  20 , a supporting seat  25  pivotally supporting the lamp holder housing  20  from below, and an LED lamp assembly  30  (hereinafter referred to as the lamp assembly  30 ) pivotally installed in the lamp holder housing  20 . 
         [0024]    As shown in  FIG. 3  and  FIG. 4 , the lamp holder housing  20  is composed of an upper half  21  and a lower half  22 . The lamp holder housing  20  contains therein a partition  23 , a stationary gear  26 , a vertical driving device  80  and a horizontal driving device  90 . Therein, the partition  23  divides the interior of the lamp holder housing  20  into a lamp compartment  24   a  and a machine compartment  24   b.    
         [0025]    As further shown in  FIG. 3  through  FIG. 8 , the lamp assembly  30  comprises a lamp casing  40 , two LED circuit boards  50 , a reflective lens  60 , a lens frame  70  and an outer frame  75 . 
         [0026]    The lamp casing  40  of the lamp assembly  30  may have its back optionally equipped with a circular rack  48  according to practical needs. The lamp casing  40  may also have its right and left laterals each optionally equipped with a pivot  46  according to practical needs. With the pivots  46  of the lamp casing  40 , the lamp assembly  30  is pivotally installed in the lamp compartment  24   a  of the lamp holder housing  20 . 
         [0027]    Referring to  FIG. 3 , the vertical driving device  80  includes a reversible motor  81  and a pinion  82 . Therein, the reversible motor  81  of the vertical driving device  80  is installed inside the machine compartment  24   b  of the lamp holder housing  20  and fixed to the partition  23  of the lamp holder housing  20 . The pinion  82  of the vertical driving device  80  is driven by the reversible motor  80  and meshes with the circular rack  48  of the lamp assembly  30 . 
         [0028]    As shown in  FIG. 3  and  FIG. 4 , when the reversible motor  81  of the vertical driving device  80  is activated, the gear-engagement movement established between the pinion  82  of the vertical driving device  80  and the circular rack  48  of the lamp assembly  30  drives the lamp assembly  30  to rotate against the pivots  46  so as to tilt up and down inside the lamp compartment  24   a  of the lamp holder housing  20 , thereby achieving vertical change of the illumination angle of the LED searchlight  10 . 
         [0029]    As shown in  FIG. 3 , the stationary gear  26  is fixed to the supporting seat  25  and forms an immovable part of the supporting seat  25 . 
         [0030]    As shown in  FIG. 3 , the horizontal driving device  90  includes a reversible motor  91  and a pinion  92 . Therein, the reversible motor  91  of the horizontal driving device  90  is fixed to the bottom of the machine compartment  24   b  of the lamp holder housing  20 , or, fixed to the bottom of the lower half  22  of the lamp holder housing  20 . The pinion  92  of the horizontal driving device  90  is driven by the reversible motor  91  and meshes with the stationary gear  26  of the supporting seat  25 . 
         [0031]    As shown in  FIG. 3 , the supporting seat  25  pivotally supports the lamp holder housing  20  from below. When the reversible motor  91  of the horizontal driving device  90  is activated, the gear-engagement movement established between the pinion  92  of the horizontal driving device  90  and the stationary gear  26  of the supporting seat  25  drives the lamp holder housing  20  and in turn the lamp assembly  30  a installed in the lamp compartment  24   a  to turn right or left with respect to the supporting seat  25 , thereby achieving horizontal change of the illumination angle of the LED searchlight  10 . 
         [0032]    As shown in  FIG. 7  and  FIG. 8 , the lamp casing  40  of the lamp assembly  30  contains therein a recess  41  for receiving the LED circuit boards  50  and the reflective lens  60 . 
         [0033]    As shown in  FIG. 3  through  FIG. 8 , for facilitating heat dissipation, the lamp casing  40  of the lamp assembly  30  has its top and/or bottom provided with plural heat-dissipating ribs  45 . Moreover, the recess  41  of the lamp casing  40  has its upper edge portion  42  and lower edge portion  43  each provided with a plurality of clamping blocks  44  for fixing the corresponding LED circuit board  50 . 
         [0034]    To assemble the lamp assembly  30 , the LED circuit boards  50  are installed into the lamp casing  40  first, and then the reflective lens  60  is fitted. After installed into the lamp casing  40 , the LED circuit boards  50  are close to the heat-dissipating ribs  45  formed at the top (or bottom) of the lamp casing  40 , so that heat generated by the LED circuit boards  50  can be dissipated effectively. 
         [0035]    As shown in  FIG. 4  through  FIG. 8 , the reflective lens  60  has a surface composed of at least one set of double parabolic lens units  61 . Therein, each of the double parabolic lens units  61  includes a first parabolic lens surface  62  and a second parabolic lens surface  63  that are integrated as a unity and both have concave parabolic lens surfaces for reflecting light. In addition, each said double parabolic lens unit  61  has slits  64  formed at the focuses of the first parabolic lens surface  62  and the second parabolic lens surface  63 , respectively. 
         [0036]    As shown in  FIG. 4  through  FIG. 7 , each of the LED circuit boards  50  is provided with a plurality of LEDs  55 . When the LED circuit boards  50  and the reflective lens  60  are assembled into the recess  41  of the lamp casing  40 , the LEDs  55  of one of the LED circuit boards  50  are located in and exposed at the slits  64  of the first parabolic lens surfaces  62  of the double parabolic lens unit  61  of the reflective lens  60 , and serve as LED light sources at the focuses of the first parabolic lens surfaces  62 . 
         [0037]    Similarly, the LEDs  55  of the other LED circuit board  50  are located in and exposed at the slits  64  of the second parabolic lens surfaces  63  of the double parabolic lens unit  61  of the reflective lens  60 , and serve as LED light sources at the focuses of the second parabolic lens surfaces  63 . 
         [0038]    As shown in  FIG. 7 , light beams emitted from the LEDs  55  of the LED circuit board  50  are reflected by the corresponding first parabolic lens surface  62  (or second parabolic lens surface  63 ) of the reflective lens  60  into parallel light beams. Therefore, the disclosed lamp assembly  30  can project or emit parallel LED light beams far to the front. 
         [0039]    As shown in  FIG. 4  through  FIG. 8 , the lens frame  70  has a lens  71  for closing the recess  41  of the lamp casing  40 . The outer frame  75  serves to enclose and hold the lens frame  70  and is fixed to the lamp casing  40 . As shown in  FIG. 7 , after assembled, the lens  71  of the lens frame  70  extends from the outer frame  75 , so that when the outer frame  75  is fixed to the lamp casing  40 , the lens frame  70  and the outer frame  75  are together fixed to the lamp casing  40 . 
         [0040]    As shown in  FIG. 7 , after assembled, the lens  71  of the lens frame  70  allows parallel LED light beams to pass therethrough and prevent water from entering the interior of the lamp casing  40 , thereby protecting the LED circuit boards  50  installed in the lamp casing  40  from moisture. 
         [0041]      FIG. 5  shows another embodiment of the lamp assembly  30 . In the present embodiment, the lamp casing  40  is not provided with the circular rack  48 . Alternatively, in still another embodiment of the lamp assembly  30 , the lamp casing  40  is not laterally provided with the pivots  46 . When using the lamp assembly  30  such configured, the disclosed reflective LED searchlight  10  is still effective in casting parallel LED light beams far to the front, but does not support vertical or horizontal change of its illumination angle. 
         [0042]    The present invention has been described with reference to the preferred embodiments and it is understood that the embodiments are not intended to limit the scope of the present invention. Moreover, as the contents disclosed herein should be readily understood and can be implemented by a person skilled in the art, all equivalent changes or modifications which do not depart from the concept of the present invention should be encompassed by the appended claims.