Abstract:
A light emitting diode bulb includes a driving circuit board, a lighting unit, and a housing. The driving circuit board has one or more extending parts formed on one side, and a group of electrically connecting pins are disposed on the other side. An electrode is attached to one surface of each of the extending parts. The lighting unit is electrically connected to the electrodes. The housing packages the driving circuit board and the lighting unit, the electrically connected pins extend beyond the housing. The light emitting bulb has advantages of easy manufacture and low cost since the driving circuit board is electrically connected to the lighting unit directly and the housing then packages the driving circuit board and the lighting unit.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to light bulb, and in particular to a light emitting diode bulb. 
     2. Description of Related Art 
     A light emitting diode is a kind of semiconductor device and has advantage of long service time, with advances in semiconductor packaging technology and the advantage mentioned above, light emitting diode is gradually replacing the fluorescent tubes and incandescent lamps and widely used in indoor and outdoor lighting and vehicle lights. 
     Reference is made to  FIG. 1 , which shown a conventional light emitting diode bulb. The light emitting bulb includes a housing  10  having a platform  101  for arranging a substrate  201  mounting light emitting diode  20  thereon. The substrate  201  is electrically connected to at least one light emitting diode die  202 . At least one hole  102  allowing wires  203  passing therethrough is formed on the platform  101 , the wires  203  are used for electrically connecting the substrate  201  and a circuit board  30  arranged within the accommodating space  103  of the housing  10 . A plurality of pins  301  electrically connected to the circuit board  30  extend beyond the housing  10 . The light emitting diode bulb further includes a shell  40  assembled with the platform  101  such that the light emitting diode  20  is arranged between the shell  40  and the platform  101 . When the pins  301  of the light emitting diode bulb are socketed into a lamp holder, the circuit board  30  drives the light emitting diode  20  to light. 
     The light emitting diode  20  and the circuit board  30  are respectively arranged on the platform  101  and within the accommodating space  103 , and electrically connected to the circuit board  30  via the wires  203 , considerable time is spent on assembling the light emitting diode  20 , the circuit board  30 , and the wires  203 , and is expensive. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a light emitting diode bulb having a driving circuit board in directly electrical connection with lighting unit, where the driving circuit board and the lighting unit are packaged within a housing, so that the light emitting bulb has advantages of easily manufacturing and low cost. 
     Accordingly, the present invention provides a light emitting diode bulb comprising a driving circuit board, a lighting unit, and a housing. A driving circuit is mounted on the driving circuit board. The driving circuit board comprises one or more extending parts formed at one side thereof and a group of electrically connecting pins disposed on the other side thereof. One or more electrodes are attached to one surface of each of the extending parts. The lighting unit is electrically connected to the electrodes, the housing packages the driving circuit board and the lighting unit, and the electrically connecting pins extending beyond the housing. 
     In an embodiment of the present invention, the lighting unit comprises a transparent substrate, a circuit layer is attached to one surface of the transparent substrate and electrically connected to a plurality of light emitting diode dies. The circuit layer comprises two or more electrically connecting pads for electrically connecting to the electrodes. 
     In an embodiment of the present invention, the transparent substrate has two opposite surfaces, one of the surfaces is covered with a first transparent sheet, and the other surface is covered with a second transparent sheet. The electrically connecting pads are exposed out of the first transparent sheet. 
     In an embodiment of the present invention, a predetermined distance larger than or equal to a width of the lighting unit is between the two extending parts formed on the driving circuit board, the lighting unit is directly inserted between the extending parts, and the electrically connecting pads are electrically connected to the electrodes. 
     In an embodiment of the present invention, the housing comprises an enclosure and a shell, the enclosure is of U-shape or plate shape and comprises an accommodating space, a group of penetrating holes, and at least one tenon. The accommodating space is used for accommodating the driving circuit board, and the penetrating holes allow the electrically connecting pins passing therethrough. The tenon of hook shape is formed on an inner wall of the enclosure. The shell is of arc shape, cone shape or bullet shape and comprises an inner hollow cavity, the lower edge of the shell comprises at least one ledge, and an engaging part formed on the ledge for engaging with the tenon when the shell is assembled with the enclosure. 
     In an embodiment of the present invention, the shell is made of plastic or acrylic. 
     In an embodiment of the present invention, the enclosure is made of plastic or metal. 
     In an embodiment of the present invention, the housing is of bullet shape and comprises a cylindrical enclosure and a shell of arc, cone, or inverse U-shape extending from the enclosure. 
     In an embodiment of the present invention, the housing is made of silicone or epoxy. 
     In an embodiment of the present invention, the housing further comprises a light-diffusing component, and the light-diffusing component is titanium dioxide or silicon dioxide. 
    
    
     
       BRIEF DESCRIPTION OF DRAWING 
       The features of the invention believed to be novel are set forth with particularity in the appended claims. The invention itself, however, may be best understood by reference to the following detailed description of the invention, which describes an exemplary embodiment of the invention, taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a sectional view of a conventional light emitting diode bulb; 
         FIG. 2  is an exploded view of a lighting unit and a driving circuit board of a light emitting diode bulb according to a first embodiment of the present invention; 
         FIG. 3  is an assembled view of the lighting unit and the driving circuit board of the light emitting diode bulb according the first embodiment of the present invention; 
         FIG. 4  is a partially-enlarged sectional view of  FIG. 3 ; 
         FIG. 5  is an exploded view of the light emitting diode bulb according to the first embodiment of the present invention; 
         FIG. 6  is a perspective view of the assembled light emitting diode bulb according to the first embodiment of the present invention; 
         FIG. 7  is a sectional view of the assembled light emitting diode lamp according to the first embodiment of the present invention; 
         FIG. 8  is a perspective view of a light emitting diode bulb according to a second embodiment of the present invention; 
         FIG. 9  is an enlarged view of a light emitting diode bulb according to a third embodiment of the present invention; 
         FIG. 10  is a sectional view of the light emitting diode bulb according to the third embodiment of the present invention; 
         FIG. 11  is an exploded view of a light emitting diode bulb according to a fourth embodiment of the present invention; 
         FIG. 12  is a perspective view of the light emitting diode bulb according to the fourth embodiment of the present invention; 
         FIG. 13  is an exploded view of a light emitting diode bulb according to a fifth embodiment of the present invention; 
         FIG. 14  is a perspective view of the light emitting diode bulb according to the fifth embodiment of the present invention; and 
         FIG. 15  is an exploded view of a light emitting diode bulb according to a sixth embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A preferred embodiment of the present invention will be described with reference to the drawings. 
     Reference is made to  FIG. 2 ,  FIG. 3 , and  FIG. 4 ,  FIG. 2  and  FIG. 3  are respectively an exploded view and an assembled view of a lighting unit and a driving circuit board of a light emitting diode bulb according to a first embodiment of the present invention, and  FIG. 4  is a partially-enlarged sectional view of  FIG. 3 . The light emitting diode bulb of the present invention includes a driving circuit board  1  and a lighting unit  2 . 
     The driving circuit board  1  has a driving circuit (not shown) mounted thereon and one or more extending parts of strip shape or slice shape formed at one side thereof. A surface of each of the extending parts  11  has one or more electrodes  12  for electrically connecting to the lighting unit  2  when the lighting unit  2  is assembled with the driving circuit board  1 . The driving circuit board  1  has a group of electrically conductive pins  13  at one side opposite to the extending part, and in this embodiment, the driving circuit board  1  includes a pair of electrically conductive pins  13  disposed on the other side opposite to the extending parts  11 . 
     The lighting unit  2  includes a transparent substrate  32 . One surface of the transparent substrate  21  has a circuit layer  22  mounted thereon. A plurality of light emitting diode dies  23  are electrically connected to the circuit layer  22 . The circuit layer  22  has two or more electrically connecting pads  221  for electrically connecting to the electrodes  12  when the lighting unit  2  is assembled with the driving circuit board  1 . The surface of the transparent substrate  21  where the circuit layer  22  is mounted is covered with a first transparent sheet  24 . However, the electrically connecting pads  221  are exposed to the first transparent sheet  24  for electrically connecting to the electrodes  12  when the lighting unit  2  is assembled with the extending part  11  of the driving circuit board  1 . The other surface of the transparent substrate  21  opposite to the surface where the circuit layer  22  is mounted is covered with a second transparent sheet  25 . 
     Reference is made to  FIG. 5 ,  FIG. 6 , and  FIG. 7 , which are an exploded view, an assembled view, and a sectional view of the light emitting diode bulb according to the first embodiment of the present invention. The light emitting diode bulb further includes a housing  3  for packaging the driving circuit board  1  and the lighting unit  2 . The housing  3  is of bullet shape and includes an enclosure  31  and a shell  32 . 
     The enclosure  31  has a U-shape profile. An accommodating space  311  for accommodating the driving circuit board  1  is formed within the enclosure  31 . A bottom of the enclosure  31  has a group of penetrating holes  312  allowing the electrically connecting pins  13  passing therethrough, such that the electrically connected pins  13  are adapted into an external socket (not shown). The enclosure  31  further includes at least one tenon  313  of hook shape and used for engaging with the shell  32 . In this embodiment, the enclosure  31  is made of plastic or metal. 
     The shell  32  is of arc shape and has an inner hollow cavity. The lower edge of the shell  32  includes at least one ledge  321 , and an engaging part  322  is formed on the ledge  321  for engaging with the tenon  313  when the shell  32  is assembled with the enclosure  31 , such that the shell  32  can firmly assembled with the enclosure  31 . In this embodiment, the shell  32  is made of plastic (such as polycarbonate, PC) or acrylic (such as polypropylene, PP). 
     Reference is made to  FIG. 8 , which is a perspective view of a light emitting diode bulb according to a second embodiment of the present invention. The light emitting diode bulb includes a housing  4 . The housing  4  is made of silicone or epoxy, which is added with light-diffusing component  43  and mixed thoroughly. The light-diffusing component  43  is titanium dioxide (TiO 2 ) or silicon dioxide (SiO 2 ). The housing  4  of bullet shape is formed on the driving circuit board  1  and the lighting unit  2  by thermosetting, injection molding, or thermoforming. The housing  4  includes a cylindrical enclosure  41  and a shell  42  of arc, cone, or inverse U-shape extending from the enclosure  41 . The light generated from the lighting unit  2  is diffused by the light-diffusing component  43  and then uniformly projects from the housing  4  when the driving circuit board  1  is powered up and the lighting unit  2  is lighted. 
     Reference is made to  FIG. 9  and  FIG. 10 , which are an enlarged view and a sectional view of a light emitting diode bulb according to the third embodiment of the present invention. The light emitting bulb is similar to the first embodiment mentioned above. The difference is that a predetermined distance  14  is between two extending parts  11  of the driving circuit board  1 . The predetermined distance  14  is larger than or equal to the width of the transparent substrate  21  of the lighting unit  2 , such that the transparent substrate  21  of the lighting unit  2  can directly insert between the extending parts  11 , the transparent substrate  21  of the lighting unit  2  is fastened with the extending parts  11 , and the electrically connecting pads  221  are electrically connected to the electrodes  12 . Thereby, the thickness of the assembled driving circuit board  1  and the lighting unit  2  is smaller than that of in the first embodiment, and the process of electrically connecting the driving circuit board  1  and the lighting unit  2  is more convenient than that of in the first embodiment. 
     Reference is made to  FIG. 11  and  FIG. 12 , which are an explored view and a perspective view of a light emitting diode bulb according to a fourth embodiment of the present invention. The light emitting bulb is similar to the first embodiment mentioned above. The difference is that the housing  5  includes an enclosure  51  and a shell  52 , and the profile of the enclosure  51  is of plate shape. The enclosure  51  has an accommodating space  511  for accommodating the driving circuit board  1 . The bottom of the enclosure  51  has a group of penetrating holes  512  allowing the electrically connecting pins  13  passing therethrough, such that the electrically connected pins  13  can be adapted into an external socket (not shown). The enclosure  51  further includes at least one tenon  513  of hook shape and used for engaging with the shell  52 . 
     The shell  52  is of bullet shape and has an inner hollow cavity. The lower edge of the shell  52  includes at least one ledge  521 , and an engaging part  522  is formed on the ledge  521  for engaging with the tenon  513  when the shell  52  is assembled with the enclosure  51 , such that the shell  522  can be firmly assembled with the enclosure  51 . 
     Reference is made to  FIG. 13  and  FIG. 14 , which are an exploded view and a perspective view of a light emitting diode bulb according to a fifth embodiment of the present invention. The light emitting bulb is similar to the first embodiment mentioned above. The difference is that the driving circuit board  6  includes three extending parts  61 . A surface of each of the extending parts  61  has an electrode  62  for electrically connecting to three electrically connecting pads  221  of the lighting unit  2 . The extending parts  61  allow positive electricity and negative electricity selectively transmitting to the lighting unit  2  to switch the light emitting diode dies  23 . 
     The housing  7  includes an enclosure  71  and a shell  72 , and the profile of the enclosure  71  is of plate shape. The enclosure  71  has an accommodating space  711  for accommodating the driving circuit board  6 . The bottom of the enclosure  71  has a group of penetrating holes  712  allowing the electrically connecting pins  63  of the driving circuit board  6  passing therethrough, such that the electrically connected pins  63  can be adapted into an external socket (not shown). The enclosure  71  further includes at least one tenon  713  of hook shape and used for engaging with the shell  72 . 
     The shell  72  is of bullet shape and has an inner hollow cavity. The lower edge of the shell  72  includes at least one ledge  721 , and an engaging part  722  is formed on the ledge  721  for engaging with the tenon  713  when the shell  72  is assembled with the enclosure  71 , such that the shell  722  can be firmly assembled with the enclosure  71 . 
     Reference is made to  FIG. 15 , which is an explored view of a light emitting diode bulb according to a sixth embodiment of the present invention. The light emitting bulb is similar to the first embodiment mentioned above. The difference is that the driving circuit board  8  only includes one extending part  81  of strip shape or slice shape. A surface of the extending part  81  has two or more electrodes  82  for electrically connecting to three electrically connecting pads  221  of the lighting unit  2 . The driving circuit board  8  includes a pair of electrically conductive pins  83  disposed on the other side opposite to the extending parts  81 . 
     Although the present invention has been described with reference to the foregoing preferred embodiment, it will be understood that the invention is not limited to the details thereof. Various equivalent variations and modifications can still occur to those skilled in this art in view of the teachings of the present invention. Thus, all such variations and equivalent modifications are also embraced within the scope of the invention as defined in the appended claims.