Patent Publication Number: US-8540414-B2

Title: Detachable LED bulb

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The invention relates to electric bulbs, particularly to bulbs using LED as a light source. 
     2. Related Art 
     Light emitting diodes have extensively applied in various lighting devices because of small volume, low power-consuming and great durability. A typical LED bulb, as shown in  FIG. 1 , is composed of a heat dissipating cup  10 , a base  11 , a cover  12 , LED elements  13 , a circuit board  14  and a power driver  15 . The LED elements  13  are mounted on the circuit board  14 . The power driver  15  is electrically connected between the base  11  and the circuit board  14  through wires  16 ,  17 . 
     In such a LED bulb, the dissipating cup  10  and base  11  are integrally formed into a single piece. The connection between the power driver  15  and the circuit board  14  or the base  11  is undetachable. Thus, when the power driver  15  fails and requires to be replaced, the cover  12 , circuit board  14  and power driver  15  must be disassembled first and then the wires  16 ,  17  have to be desoldered. It is very inconvenient for both users and manufactures because the failed bulbs cannot be repaired immediately. 
     A lifetime of LED elements can usually reach about 200,000 hours or above, while a lifetime of a power driver may only last about 30,000 hours. Thus, LED elements are longer than the power driver by almost seven times in lifetime. Thus, repair or replacement for the power driver within a lifetime of LED elements is unavoidable. However, conventional LED bulbs are very unadvantageous to maintenance of power drivers. 
     SUMMARY OF THE INVENTION 
     An object of the invention is to provide a detachable LED bulb, which can be simply maintained by disassembling. 
     To accomplish the above object, the invention includes a circuit board, LED elements, heat dissipating cup, a base and a power driver. The circuit board has two power lines with a second connector. The LED elements are mounted on the circuit. The heat dissipating cup has a hollow portion, a seat for supporting the circuit and a second coupler. The base has a first coupler for coupling with the second coupler. The power driver is received in the hollow portion of the dissipating cup, is electrically connected between the base and the circuit board, and has a first connector for detachably connecting the second connector of the power lines. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-sectional view of a conventional LED bulb; 
         FIG. 2  is an exploded view of a preferred embodiment of the invention; 
         FIG. 3  is a cross-sectional view of the embodiment shown in  FIG. 3 , and 
         FIG. 4  is a cross-sectional view of another preferred embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Please refer to  FIGS. 1 and 2 . The LED bulb of the invention includes a circuit board  5 , LED elements  7 , heat dissipating cup  2 , a base  3 , a cover  4  and a power driver  6 . 
     The base  3  includes a conductive cap  30  for introducing external electricity and a first coupler  31  for coupling with the heat dissipating cup  2 . In this embodiment, the first coupler  31  is a cylinder with a first thread  310 . The first coupler  31  is formed with an opening  32 . 
     The heat dissipating cup  2  is made of a metal material for dissipating heat from the LED elements  7 . A hollow portion  20  is formed in the heat dissipating cup  2  for receiving the power driver  6 . Also, the heat dissipating cup  2  is formed with a seat  21  for supporting the circuit board  5  and a second coupler  22  corresponding to the first coupler  31 . The base  3  and heat dissipating cup  2  can be assembled to integrate with each other. In this embodiment, the second coupler  22  is a threaded hole  210  with a second thread  211 . As a result, the base  3  can be screwed into the heat dissipating cup  2  by the connection of the couplers  31 ,  22 , and the base  3  and heat dissipating cup  2  are detachable. Additionally, the seat  21  is formed with a through hole  212  communicating with the hollow portion  20  and the opening  32  for allowing power lines  50  to pass. 
     The LED elements  7  are mounted on the circuit board  5 . One end of the power lines  50  is connected to the circuit board  5 , and the other end is disposed with a second connector  51 . 
     The power driver  6  is electrically connected between the base  3  and the circuit board  5 . The power driver  6  has two wires  60  with a first connector  61  corresponding to the second connector  51 . An electric connection can be made by linking the first connector  61  and the second connector  61 . The power driver  6  supplies power to the circuit board  5 . The cover  4  is fastened to the heat dissipating cup  2 . 
     There are two connections in the invention, the one is the couplers  31 ,  22  and the other one is the connectors  61 ,  51 . These connections may be detached to disassemble the bulb. After these connections are detached, the power driver  6  is easy to be replaced. It is very convenient and economical for both users and manufactures. 
       FIG. 4  shows another preferred embodiment of the invention. In this embodiment, the first coupler  31  is implemented by two hooks  311  towards the heat dissipating cup  2 . And the second coupler  22  is implemented by a flange  214  formed on an end of the heat dissipating cup  2 . The base  3  and heat dissipating cup  2  can be assemble integrally by engaging the hooks  311  with the flange  214 . 
     While the forgoing is directed to preferred embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. As such, the appropriate scope of the invention is to be determined according to the claims.