Abstract:
The present invention is directed to a lighting master, which includes a base and a lighting module. A region defined between the base and a housing accommodates a power module. The lighting module is disposed over the base. The base has an outer surface to be bonded with an inner surface of the housing.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The entire contents of Taiwan Patent Application No. 099217932, filed on Sep. 16, 2010, from which this application claims priority, are incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention generally relates to a lighting device, and more particularly to a lighting master that is capable of being matched with various housings. 
     2. Description of Related Art 
     Due to various advantages of a light-emitting diode (LED) such as small volume, short response time, low power consumption, high reliability and high feasibility of mass production, the LED is replacing conventional lighting devices such as light bulbs or fluorescent lamps. 
     However, the specifications of LED lamps and housing styles from a variety of manufacturers are oftentimes different from each other. It is therefore difficult to construct the LED lamps in modular parts, and the non-modular LED lamps are wastefully accumulated in warehouses. Moreover, when the LED lamp specification, or its housing style changes, it is difficult or impossible to reuse constructing parts of the LED lamp by disintegrating the LED lamp. 
     Accordingly, a need has arisen to propose a modular architecture of LED devices such that the LEDs, the housings and other constructing parts can be matched in use, therefore reducing accumulation in warehouses and improving effective usage. 
     SUMMARY OF THE INVENTION 
     In view of the foregoing, it is an object of the embodiment of the present invention to provide a lighting master that is capable of being matched with various housings to form a variety of lighting devices. 
     According to one embodiment, a lighting master includes a base and a lighting module. The base and a housing define a space to accommodate a power module. The lighting module is disposed over the base. The base has an outer surface to be bonded with an inner surface of the housing. 
     According to another embodiment, a lighting device includes a housing, a power module and a lighting master. The lighting master includes a base and a lighting module disposed over the base. The base and the housing define a space to accommodate the power module. The base has an outer surface to be bonded with an inner surface of the housing. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows an exploded view of a lighting device according to a first embodiment of the present invention; 
         FIG. 2  shows a cross-sectional view of the base of  FIG. 1 ; 
         FIG. 3  shows an exploded view of a lighting device according to a second embodiment of the present invention; 
         FIG. 4  shows a cross-sectional view of the base of  FIG. 3 ; 
         FIG. 5A  shows an exploded, view of a lighting device according to a third embodiment of the present invention; 
         FIG. 5B  shows a cross-sectional view of the hollow cylinder with the hollow annular insulation sheet and the printed circuit board of  FIG. 5A ; and 
         FIG. 6  shows an exploded view of a lighting device according to a fourth embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  shows an exploded view of a lighting device according to a first embodiment of the present invention. Although a light-emitting diode (LED) is demonstrated, the present invention may be adapted to other lighting elements such as an organic light-emitting diode (OLED). 
     The lighting device primarily includes a lamp cover  10 , a lighting master  12 , a power module  14  and a housing  16 . In the embodiment, the lighting master (or a light engine)  12  includes a base  120 , a heat conductive sheet  121 , a heat conductive substrate  122  and a lighting module  123 . Specifically, the base  120  includes a plate  1201  and a hollow cylinder  1202  extended from a surface of the plate  1201 . The plate  1201  and the hollow cylinder  1202  may be manufactured integrally, or may be individually made and then combined. The base  120  may be made of metal (such as copper or silver), ceramic or other heat conductive materials. 
       FIG. 2  shows a cross-sectional view of the base  120 . Specifically, the hollow cylinder  1202  has an inclined outer surface. The outer surface of the hollow cylinder  1202  may further have one or more steps, and a junction between the plate  1201  and the hollow cylinder  1202  may also form a step. These steps are used to bond with corresponding reverse steps on an inner surface of the housing  16 . In a modified embodiment, the outer surface of the hollow cylinder  1202  may have screw thread (not shown), which is used to bond with corresponding reverse screw thread on the inner surface of the housing  16 . Further, a side surface of the plate  1201  may have one or more notches  1203 , which are used to fasten to corresponding hooks  160  of the housing  16 . The space defined between the hollow cylinder  1202  and the housing  16  is used to accommodate the power module  14  or other elements such as a heat dissipating fan (not shown). In the embodiment, the surface of a printed circuit board (PCB)  140  of the power module  14  is perpendicular to the plate  1201  of the base  120 . 
     The heat conductive substrate  122  may be made of metal (such as copper or silver), ceramic or other heat conductive materials. The lighting module  123  such as an LED module is attached, for example, by soldering, to a surface the heat conductive substrate  122  whose surface faces towards the lamp cover  10  (or backwards the housing  16 ). The heat conductive sheet  121  is disposed between the heat conductive substrate  122  and the base  120 . The heat conductive substrate  122  may be screwed to the base  120  with screws  124  through threaded holes  1220  of the heat conductive substrate  122  and threaded holes  1204  of the plate  1201 . The power/signal lines of the power module  14  may be connected to the lighting module  123  via a line outgoing hole  1205  of the plate  1201  and a line outgoing hole  1221  of the heat conductive substrate  122 . 
     In the embodiment, the housing  16  includes a bottom housing  161 , a top housing  162  and a lamp head  163  covering the top housing  162 . Specifically, the top housing  162  is adjacent to the bottom housing  161 , and the lamp head  163  may be screwed into a lamp socket (not shown) in order to transfer power provided by the lamp socket to an input node of the power module  14 . The housing  16  may have a shape similar to that of a conventional light bulb or have other shapes. Heat dissipating fins may be formed on a surface of the bottom housing  161 . The constructing parts of the housing  16  may be manufactured integrally, or may be individually made and then combined. The housing  16  may be made of plastic, metal, ceramic or other heat conductive materials. The lamp cover  10  is an optional part that may, for example, use one or more inner hooks  100  or other fastening means, to fasten to corresponding projecting points  164  of the housing  16 . 
     According to the present embodiment, the constructing parts of the lighting master  12  are assembled and tested to build a half-finished product, which may be later matched with other parts (such as the lamp cover  10 , the power module  14  or the housing  16 ) to form various lighting devices according to different designs. Accordingly, the accumulation in the warehouse may be substantially reduced. 
       FIG. 3  shows an exploded view of a lighting device according to a second embodiment of the present invention. The present embodiment  FIG. 3 ) is similar to the first embodiment ( FIG. 1 ) with the distinction that the lighting module  123  of the present embodiment is directly attached, for example, by soldering, onto the plate  1201  whose surface faces towards the lamp cover  10  (or backwards the housing  16 ), therefore omitting the heat conductive sheet  121  and the heat conductive substrate  122 , and leaving the threaded hole  1204  out of the plate  1201 . In a modified embodiment, as shown in  FIG. 4 , a printed circuit board  126  with a lighting module  123  and a control circuit  125  may be embedded in a hollow of the plate  1201 . Some electronic elements may be mounted on the control circuit  125 . Further, the control circuit  125  may be replaced with the printed circuit board  140  of the power module  14 . In the embodiment, the lighting module  123  is disposed on the printed circuit board  126  whose surface faces towards the lamp cover  10  (or backwards the housing  16 ), and the control circuit  125  is disposed on the printed circuit board  126  whose surface faces towards the housing  16 . 
       FIG. 5A  shows an exploded view of a lighting device according to a third embodiment of the present invention. The present embodiment ( FIG. 5A ) is similar to the first embodiment ( FIG. 1 ) with the distinction that the surface of the printed circuit board  140  of the power module  14  is parallel to the plate  1201  of the base  120 . Further, the printed circuit board  140  according to the present embodiment may have a circular shape similar to that of the bottom housing  161 . The present embodiment may further have a hollow annular insulation sheet  13  disposed between the base  120  and the power module  14 . In the embodiment, the power module  14  has a size that is substantially less than the size of the power module  14  of the first embodiment ( FIG. 1 ) or the second embodiment ( FIG. 3 ). As a result, the hollow cylinder  1202  of the present embodiment has a length that is less than the length of the hollow cylinder  1202  of the first embodiment ( FIG. 1 ) or the second embodiment ( FIG. 3 ).  FIG. 5B  shows a cross-sectional view of the hollow cylinder  1202  with the hollow annular insulation sheet  13  and the printed circuit board  140  according to the third embodiment. 
       FIG. 6  shows an exploded view of a lighting device according to a fourth embodiment of the present invention. The present embodiment ( FIG. 6 ) is similar to the third embodiment ( FIG. 5A ) with the distinction that the lighting module  123  of the present embodiment is directly attached, for example, by soldering, onto the plate  1201  whose surface faces towards the lamp cover  10  (or backwards the housing  16 ), therefore omitting the heat conductive sheet  121  and the heat conductive substrate  122 , and leaving the threaded hole  1204  out of the plate  1201 . 
     Although specific embodiments have been illustrated and described, it will be appreciated by those skilled in the art that various modifications may be made without departing from the scope of the present invention, which is intended to be limited solely by the appended claims.