Abstract:
An even luminance, high heat dissipation efficiency, high power LED lamp structure includes an aluminum extrusion body, an aluminum die cast front casing and an aluminum die cast rear casing respectively provided at two distal ends of the aluminum extrusion body, a PC board mounted inside the aluminum extrusion body, LEDs mounted in different LED mounting faces of the PC board at different angles, an inner cover plate decorating the inside of the aluminum die cast front casing, a transparent outer cover covering the bottom side of the aluminum extrusion body and sealed with a water seal, and a retaining device fastened to the aluminum extrusion body to secure the transparent outer cover in place.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to LED lamps and more particularly, to an even luminance, high heat dissipation efficiency, high power LED lamp structure that is practical for mass production to reduce the cost. 
         [0003]    2. Description of the Related Art 
         [0004]    Conventional light fixtures commonly use incandescent lamp bulbs or high-voltage sodium (mercuric) lamp bulbs as light source means to give off light. However, these lamp bulbs have high power consumption, low luminance efficiency and environmental unfriendly characteristics. However, because these light sources emit light in all directions, reflector means is necessary to reflect light toward a specific direction for floodlight illumination. Therefore, the effective utility of light is low. 
         [0005]    Further, high brightness LEDs (light emitting diodes) have the advantages of small size, low power consumption and long service life. Therefore, high brightness LEDs are currently regarded as the next generation light source for illumination. 
         [0006]    Commercial high power LED lamps include four types. The first type uses a regular lampshell for conventional high power lamp and has LEDs be bonded to the inside of the lampshell so that the lampshell dissipates heat from the LEDs during operation of the LEDs. The second type has LEDs and a heat sink (aluminum extrusion) be incorporated into a LED light source module, and then uses a regular lampshell for conventional high power lamp to hold the LED light source module on the inside. The third type has considered the problem of LED heat dissipation before designing the lampshell so that the heat dissipation structure is visible from the outside. This design employs a conventional lampshell fabrication technique, i.e., an aluminum die casting technique to make a lampshell for high power LED lamp. The fourth type is based on LED heat dissipation considerations, employing an aluminum extrusion technique to make the lampshell for high power LED lamp. 
         [0007]    The aforesaid four types of high power LED lamps are still not satisfactory in function and have drawbacks as follows: The first type of high power LED lamp uses a conventional lampshell for high power lamp without considering the problem of LED heat dissipation. Because the problem of LED heat dissipation is not taken into consideration, iron or aluminum is used for making the lampshell. However, iron has poor heat dissipation efficiency. When aluminum is selected, aluminum alloy 1000 series should be used for making the lampshell by means of employing a die casting technique. However, the die cast aluminum alloy lampshell has a low heat dissipation efficiency. Further, for the sake of beauty, the die cast aluminum alloy lampshell may be painted with a powder paint or coating with a layer of plastic coating. The powder paint or plastic coating makes dissipation of heat worse. 
         [0008]    The second type of high power LED lamp has LEDs and a heat sink (aluminum extrusion) be incorporated into a LED light source module, and then uses a regular lampshell for conventional high power lamp to hold the LED light source module. It seems that the heat sink can dissipate heat from the LEDs. However, because the lampshell has a low heat dissipation efficiency, this second type of high power LED lamp encounters the same problems as the aforesaid first type. 
         [0009]    The third type has considered the problem of LED heat dissipation before designing the lampshell, and the heat dissipation structure is visible from the outside. However, because the lampshell is made of aluminum alloy 1000 series by means of die casting, the heat dissipation efficiency of the lampshell is low. To provide a relatively greater heat dissipation surface area, much aluminum alloy material should be used. In consequence, the lampshell is heavy and big. Therefore, this is not a good choice. Further, for the sake of beauty, the lampshell may be coated with a layer of powder paint or coated with a layer of plastic coating, lowering the heat dissipation efficiency. 
         [0010]    The fourth type of high power LED lamp is based on LED heat dissipation considerations, employing an aluminum extrusion technique to make the lampshell. Aluminum alloy series 5000 or 6000 is usually used for the advantage of excellent heat dissipation efficiency. However, because the lampshell is simply a tow-dimensional design, its structure is simple and monotonous. Therefore, the shape design of the lampshell cannot satisfy consumers. 
         [0011]    Further, conventional high power LED light source designs have another common drawback, i.e., uneven luminance. Therefore, these high power LED light source signs cannot satisfy user&#39;s requirements or meet law requirements on lighting arrangements. 
         [0012]    Therefore, it is desirable to provide a high power LED lamp structure that eliminates the aforesaid problems. 
       SUMMARY OF THE INVENTION 
       [0013]    The present invention has been accomplished under the circumstances in view. It is one object of the present invention to provide an even luminance, high heat dissipation efficiency, high power LED lamp structure, which has the lamp housing thereof formed of an aluminum die cast front casing, an aluminum die cast and an aluminum extrusion body, providing an enhanced heat dissipation efficiency and causing a sense of beauty. Further, the aluminum extrusion type body has a substantially M-shaped cross section (see  FIG. 3 ) that facilitates LED optical design to provide even illumination. Further, this arrangement facilitates mass production to lower the cost. 
         [0014]    It is another object of the present invention to provide an even luminance, high heat dissipation efficiency, high power LED lamp structure, which has the printed circuit board thereof provide multiple LED mounting faces for supporting LEDs at different angles to satisfy high power light source lighting arrangement. 
         [0015]    To achieve these and other objects of the present invention, the even luminance, high heat dissipation efficiency, high power LED lamp structure comprises a front casing; a body, the body comprising a first end, a second end opposite to the first end, and an accommodation space, the first end being connected with the front casing; a rear casing, the rear casing comprising a first end connected to the second end of the body, a second end opposite to the first end of the rear casing, and a connection means provided at the second end of the rear casing; a printed circuit board mounted in the accommodation space inside the body; at least one light emitting diode installed in the printed circuit board for emitting light; a light transmissive outer cover fastened to a bottom side of the body and covered over the printed circuit board for output of light from the at least one light emitting diode; and a retaining device provided at a bottom side of the light transmissive outer cover to secure the light transmissive outer cover to the body, the retaining device comprising a connection means connected to the connection means of the rear casing. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]      FIG. 1  is an exploded view of an even luminance, high heat dissipation efficiency, high power LED lamp structure according to the present invention. 
           [0017]      FIG. 2  is an elevational assembly view of the even luminance, high heat dissipation efficiency, high power LED lamp structure according to the present invention. 
           [0018]      FIG. 3  is a schematic cross-sectional view of the body and printed circuit board of the even luminance, high heat dissipation efficiency, high power LED lamp structure according to the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0019]      FIG. 1  is an exploded view of an even luminance, high heat dissipation efficiency, high power LED lamp structure according to the present invention.  FIG. 2  is an elevational assembly view of the even luminance, high heat dissipation efficiency, high power LED lamp structure according to the present invention. As illustrated, the even luminance, high heat dissipation efficiency, high power LED lamp structure according to the present invention comprises a front casing  10 , a body  30 , a rear casing  40 , a printed circuit board  50 , at least one light emitting diode  60 , an inner cover plate  70 , at least one optical member  75 , a water seal  80 , a transparent outer cover  90 , and a retaining device  100 . 
         [0020]    The front casing  10  can be, for example, but not limited, an aluminum die cast for the consideration of the shape design of the LED lamp structure. The heat dissipation efficiency of the aluminum die cast is not high. However, because the major part of the heat dissipation function of the LED lamp structure is done through the body  30 , the front casing  10  needs not to have a heat dissipation function, and the LED lamp structure can be made having a three-dimensional configuration to satisfy consumers&#39; demands and to facilitate the promotion of the LED lamp structure. 
         [0021]    The body  30  has its one end connectable with the front casing  10  for heat dissipation. Further, the body  30  defines an accommodation space  31 . The body  30  can be extruded from aluminum for the advantage of excellent heat dissipation efficiency. However, this is not a limitation. Further, radiation fins  32  are protruded from the outer wall of the body  30  to enhance heat dissipation. 
         [0022]    The rear casing  40  has one end thereof connectable to the other end of the body  20 , an opposite end thereof provided with a first connection means  41 . The rear casing  40  can be, for example, but not limited, an aluminum die cast for the consideration of the shape design of the LED lamp structure. The heat dissipation efficiency of the aluminum die cast is not high. However, because the major part of the heat dissipation function of the LED lamp structure is done through the body  30 , the rear casing  40  needs not to have a heat dissipation function, and the LED lamp structure can be made having a three-dimensional configuration to satisfy consumers&#39; demands and to facilitate the promotion of the LED lamp structure. An aluminum die cast lampshell for high power LED lamp is heavy and big. Further, the manufacturing cost of an aluminum die cast lampshell for high power LED lamp is high. Therefore, the invention has the front casing  10  and rear casing  40  made of aluminum through a die cast technique, and the body  30  extruded from aluminum. Thus, the size of the LED lamp structure can be minimized to below one-third of original and the related tooling cost can be greatly reduced while, and the shape of the LED lamp structure can be made attractive. 
         [0023]    The printed circuit board  50  can be, for example, but not limited to, an aluminum printed circuit board using an aluminum substrate and mounted in the accommodation space  31  inside the body  30 . The printed circuit board  50  provides the necessary circuits for the light emitting diodes  60  and dissipates heat from the light emitting diodes  60  initially. 
         [0024]    The light emitting diodes  60  are high-brightness LEDs for providing the necessary light source for illumination. The number of the light emitting diodes  60  can be changed subject to actual requirement. 
         [0025]    The inner cover plate  70  is mounted inside the front casing  10  to beautify the internal arrangement. 
         [0026]    The optical member  75  is for example but not limited to a lens or a light reflection cup, and disposed below the light emitting diodes  60  for changing the radiating angle of the light emitting diodes  60  and further for adjusting the light distributed curve, so as to meet the requirement. 
         [0027]    The water seal  80  can be, for example, but not limited to, a rubber packing strip provided at the bottom side of the body  30  to prevent penetration of rainwater. 
         [0028]    The transparent outer cover  90  is provided at the bottom side of the water seal  80  for output of the light source. The transparent outer cover  90  can be made of, for example, but not limited to glass or plastics. 
         [0029]    The retaining device  100  is provided at the bottom side of the transparent outer cover  90 , having a second connection means  101  for the connection of the first connection means  41 . 
         [0030]    The even luminance, high heat dissipation efficiency, high power LED lamp structure further comprises a gasket plate  110  set between the front casing  10  and the body  30  to prevent penetration of outside rainwater into the inside of the body  30 , thereby protecting the internal printed circuit board  50  and the light emitting diodes  60 . 
         [0031]    The even luminance, high heat dissipation efficiency, high power LED lamp structure further comprises a power supply circuit (not shown) mounted, either wholly or partially, in the front casing  10  or on the outside the front casing  10 , the body  30  and the rear casing  40 , to provide the light emitting diodes  60  with the necessary working voltage. Because the power supply circuit design is of the known art and not within the scope of the claims of the present invention, no further detailed description in this regard is necessary. 
         [0032]    Thus, the front casing and rear casing of the even luminance, high heat dissipation efficiency, high power LED lamp structure are aluminum die cast members and the body is an aluminum extrusion component. When the front casing, the rear casing and the body are assembled together, they provide excellent heat dissipation efficiency. Further, the aluminum extrusion type body has a substantially M-shaped cross section (see  FIG. 3 ) that facilitates LED optical design to provide even illumination. Further, this arrangement facilitates mass production to lower the cost. When compared to conventional high power LED lamp designs, the invention involves an inventive step. 
         [0033]      FIG. 3  is a schematic cross-sectional view of the body and printed circuit board of the even luminance, high heat dissipation efficiency, high power LED lamp structure according to the present invention. As illustrated, the printed circuit board  50  has multiple LED mounting faces  51 - 55  disposed at different angles for holding LEDs at different angles. For example, the LED mounting faces  52  and  54  slope leftwards or rightwards at 30-degrees respectively; the LED mounting faces  51  and  55  slope rightwards or leftwards at 45-degrees respectively; the LED mounting faces  53  extends in horizontal. 
         [0034]    Therefore, the even luminance, high heat dissipation efficiency, high power LED lamp structure of the present invention eliminates the drawbacks of the prior art designs and has advantages including: a) the arrangement of the aluminum die cast front casing and rear casing and aluminum extrusion body provides an enhanced heat dissipation efficiency, causes a sense of beauty, and lowers the manufacturing cost of the lamp structure, and b) the printed circuit board provides multiple LED mounting faces for supporting LEDs at different angles to satisfy high power light source lighting arrangement. 
         [0035]    Although particular embodiments of the invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.