Light-emitting diode assembly and method of fabrication

#The present invention relates generally to light-emitting diode (LED) assemblies, and more particularly to an LED assembly with improved heat dissipation ability so that heat generated by the LED of the assembly can be effectively removed. The present invention relates also to a method for packaging the LED.

#Light-emitting diode (LED) is a highly efficient light source currently used widely in such field as automobile, screen display, and traffic light indication. When the LED operates to give off light, heat is accordingly produced. If not rapidly and efficiently removed, the heat produced may significantly reduce the lifespan of the LED. Therefore, a heat dissipation device is required to dissipate the heat from the LED.

#FIG. 9 shows an LED module 10 in accordance with related art which has already been packaged and is ready for use. The LED module 10 includes an LED die (not visible) therein and a pair of conductive pins 14 extending laterally outwards from opposite sides thereof. The LED module 10 is mounted within a through hole 121 defined in a circuit board 12, and a flat bottom surface of the LED module 10 is maintained in thermal contact with a metal plate 13 placed under the circuit board 12. The LED die of the LED module 10 is electrically connected to the circuit board 12 via the conductive pins 14. When the LED module 10 gives off light, the LED die contained in the LED module 10 generates a large amount of heat. The heat generated by the LED die of the LED module 10 is transferred to the metal plate 13 for dissipation.

#FIG. 1 is an exploded, isometric view of an LED assembly in accordance with a first embodiment of the present invention;

#FIG. 2 is an exploded, isometric view of the LED assembly of FIG. 1, as viewed from another aspect;

#FIG. 3 is an assembled, isometric view of the LED assembly of FIG. 1;

#FIGS. 1-3 illustrate an LED assembly in accordance with a first embodiment of the present invention. The LED assembly includes a packaged LED module 30, a light reflector 40, a heat dissipation device 50, a mounting frame 60, and a power source line 70.

#The LED module 30 has already been packaged into a single unit and is ready for use. As with the LED module 20 shown in FIG. 10, the LED module 30 has a stand-up configuration. The LED module 30 includes at least an LED die (not visible) therein and a plurality of conductive pins 32, 34 extending downwardly from a flat bottom surface 36 of the LED module 30. The more LED dies the LED module 30 contains, the brighter it will be when giving off light. As shown in this embodiment, the LED module 30 has eight conductive pins 32, 34; accordingly, the LED module 30 includes seven LED dies therein, wherein the conductive pin 34 functions as a common pole for being electrically connected to a positive pole (or a negative pole) of an external power source (not shown) via the power source line 70, while the other conductive pins 32 are thermally and electrically connected to the heat dissipation device 50, which in turn is electrically connected to the negative pole (or the positive pole) of the external power source.

#The heat dissipation device 50 is made of highly thermally conductive material such as copper, aluminum, or their alloys. The heat dissipation device 50 as shown in this embodiment includes a central column 54 and a plurality of circular-shaped fins 52 extending laterally outwardly from an outer periphery of the column 54. The column 54 projects upwardly from the topmost fin 52 of the heat dissipation device 50 to form a protrusion 55. The protrusion 55 defines a plurality of mounting holes 542 therein for fittingly receiving the conductive pins 32 of the LED module 30. When the LED module 30 is mounted to the heat dissipation device 50, the bottom surface 36 of the LED module 30 is kept in thermal and physical contact with a top surface of the protrusion 55 to thereby increase the contacting surface area between the LED module 30 and the heat dissipation device 50. The column 54 defines a longitudinal positioning hole 56 in a bottom portion thereof.