Patent Publication Number: US-2012032574-A1

Title: Structure of led (light-emitting diode) lighting bulb

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a structure of LED (Light-Emitting Diode) lighting bulb, and more particular to a structure of LED lighting bulb composed of a fin base, a pillar, a circuit board, an electrical connector, and a cover, wherein the pillar and the circuit board are arranged to be releasably mounted so that when the circuit board is broken or fails to properly function, the circuit board can be easily replaced to ensure ready maintenance, and the structure is applicable to a regular light bulb, a power-saving light bulb, or the similar lighting bulbs. 
     2. Description of Related Art 
     A traditional light bulb comprises tungsten filaments for giving off light. A spherical cover of the traditional light bulb is usually made of glass and contains therein a toxicant substance. When a light bulb not longer works for giving off light, it is common to remove and discard the bulb and a new bulb is instead mounted. This often leads to pollution or contamination to the environment. 
     The development of science and technology nowadays make it possible to manufacture lighting bulb with LEDs for substitute of the traditional light bulbs that consume a large amount of electrical energy and are not environmentally friendly. The LEDs in the applications as a light bulb must be mounted on a circuit board and electrical connection is made so as to properly energize the LEDs for giving off light. Most of the cases where an LED based lighting bulb does not work properly for giving off light are due to malfunctioning of the circuit board. Thus, when an LED based lighting bulb no longer works, although the cause for malfunctioning can be the circuit board or the LEDs themselves, yet it is not possible for the conventional design to individually replace the circuit board or the LEDs. And, it also requires replacing the whole LED based lighting bulb with a new one. This makes it difficult to lower the cost and also makes it hard for recycling, leading to secondary environmental contamination. 
     In view of these drawbacks of the conventional lighting, the present invention aims to provide a structure of LED lighting bulb that allows for easy replacement of circuit structure and convenience of maintenance, so that a user may easily conduct a process of replacement and easy use to thereby ensure convenience of use for the general users. 
     SUMMARY OF THE INVENTION 
     Accordingly, the primary objective of the present invention is to provide a structure of LED (Light-Emitting Diode) lighting bulb, which is composed of a fin base, a pillar, a circuit board, an electrical connector, and a cover, wherein the fin base forms a bore extending through a central portion thereof and the pillar is received and retained in the bore of the fin base through threading engagement, whereby with the mounting arrangement of the circuit board and the pillar, easy replacement of the circuit board and ready maintenance can be realized to thereby enhance the overall practicability. 
     Another objective of the present invention is to provide a structure of LED lighting bulb, which is composed of a cover, a fin base, a pillar, and a circuit board, which are mounted in a releasable manner so as to allow for individual replacement of a single component and thus a reduction of maintenance cost to thereby improve overall convenience. 
     A further objective of the present invention is to provide a structure of LED lighting bulb, which comprises a fin base that is extended to form a shaped hood, whereby through the shaped hood, heat dissipation is improved and diverse variation of configuration is realized to thereby improve overall practicability. 
     In order to achieve the above objectives, according to the present invention, a structure of LED lighting bulb comprises a fin base, a pillar, a circuit board, an electrical connector, and a cover. The fin base forms a bore extending through a central portion thereof and the bore has an inner circumferential surface forming an internal thread. The pillar has an outer circumferential surface forming an external thread, and the pillar is received and retained in the bore of the fin base through threading engagement. The circuit board is mounted to an end of the pillar, and the circuit board carries an LED and conductor wires thereon. The electrical connector is recessed to form a hollow configuration having an inside surface forming threading, and the electrical connector is coupled to the pillar through threading engagement and is electrically connected to the conductor wires of the circuit board. The cover is mounted to the fin base. As such, through the mounting arrangement of the pillar and the circuit board, easy replacement of the circuit board and ready maintenance can be realized. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention can be fully understood from the following detailed description and preferred embodiments with reference to the accompanying drawings, in which: 
         FIG. 1  is a perspective view showing an LED (Light-Emitting Diode) lighting bulb according to an embodiment of the present invention; 
         FIG. 2  is an exploded view of the LED lighting bulb according to the embodiment of present invention; 
         FIG. 3  is a cross-sectional view showing the LED lighting bulb according to the embodiment of the present invention; 
         FIG. 4  is a cross-sectional view showing an LED lighting bulb according to another embodiment of the present invention; and 
         FIG. 5  is a cross-sectional view showing an LED lighting bulb according to a further embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to  FIGS. 1-5 , embodiments of the present invention are schematically illustrated. The present invention provides a structure of LED (Light-Emitting Diode) lighting bulb, which comprises a fin base  10 , a pillar  20 , a circuit board  30 , an electrical connector  40 , and a cover  50 . The fin base  10  forms a bore  11  extending through a central portion thereof and the bore  11  has an inner circumferential surface forming an internal thread  111 . The pillar  20  has an outer circumferential surface forming an external thread  201 . The pillar  20  is received and retained inside the bore  11  of the fin base  10  through threading engagement. The circuit board  30  is mounted to the pillar  20 . The circuit board  30  carries thereon LEDs  31  and conductor wires  32 . The electrical connector  40  is recessed to form a hollow configuration having an inside surface forming threading  401 . The electrical connector  40  is coupled to the pillar  20  through threading engagement and is electrically connected to the conductor wires  32  of the circuit board  30 . The cover  50  is coupled to the fin base  10 . As such, through the mounting arrangement of the pillar  20  and the circuit board  3 , easy replacement of the circuit board  30  and thus ready maintenance can be realized. 
     The cover  50  and the fin base  10  are made by molding moldable materials, which are preferably colored for identification and showing. The circuit board  30 , which is of a circular configuration in the instant embodiment, has an outside diameter smaller than an inside diameter of the pillar  20  to allow the circuit board  30  to be fit inside the pillar  20 ; or alternatively, the outside diameter of the circuit board  30  is greater than the inside diameter of the pillar  20  to allow the circuit board  30  to be positioned on the fin base  10 . The cover  50  and the fin base  10  can be coupled to each other through fitting or threading engagement. The pillar  20  has a length greater than a length of the bore of the fin base  10 . Further, the fin base  10  may be alternatively extended, in an outward diverging fashion, to form a shaped hood  12 , which helps improving heat dissipation performance. 
     Referring to  FIGS. 1-5 , which show schematically embodiments according to the present invention, the LED lighting bulb according to the present invention is preferably embodied in the form comprising a fin base  10 , a pillar  20 , a circuit board  30 , an electrical connector  40 , and a cover  50 . The fin base  10  forms a bore  11  extending through a central portion thereof and the bore  11  has an inner circumferential surface forming an internal thread  111 , and the fin base  10  comprises heat dissipation fins  101  mounted thereto for heat dissipation. The fins  101  are each arranged in the form of circumferentially extending ring, or can also be arranged in the form of vertically extending member or of other configuration, and are preferably formed in an integrated fashion as a unitary structure. The fin base  10  is made by molding a moldable material or is made by shaping aluminum materials or other similar materials. The moldable material, when subjected to injection molding, can be added with a desired color to provide vivid color variation on the fin base  10 . Further, the pillar  20  has an outer circumferential surface forming an external thread  201 , and the pillar  20  is received and retained inside the bore  11  of the fin base  10  through threading engagement, whereby the pillar  20  can be screwed into and out of the fin base  10 . The pillar  20  has a length greater than a length of the bore of the fin base  10 , so that the electrical connector  40  may be coupled to the pillar  20  through threading engagement, wherein the electrical connector  40  is recessed to form a hollow configuration having an inside surface forming threading  401  for engaging the pillar  20 . Further, the pillar  20  has an end to which the circuit board  30  is mounted. The circuit board  30  has an outside diameter greater than an inside diameter of the pillar  20  to allow the circuit board  30  to be positioned on the end of the pillar  20 . The circuit board  30  and the pillar  20  are separable from each other. The circuit board  30  is secured to the fin base  10  so that the circuit board  30  is kept fixed and hard to move. The circuit board  30  carries thereon LEDs  31  and conductor wires  32 , as well as other electronic components, including a ballast (not shown). The number of the LEDs  31  can be plural to meet the needs of desired lighting performance. The LEDs  31  can be mounted with SMD technology or other techniques of mounting to serve as a light source. Further, the conductor wires  32  extends through hollow interior of the pillar  20  to electrically connect to the electrical connector  40  for connection with a power source for supplying of electrical power. In an alternative form of the present invention (as shown in  FIG. 4 ), the circuit board  30  has an outside diameter that is smaller than an inside diameter of the pillar  20  so that the circuit board  30  can be fit inside the pillar  20  and the circuit board  30  can be held through the pillar  20 . Similarly, the circuit board  30  carries thereon LEDs  31  and conductor wires  32 , as well as other electronic components, including a ballast (not shown), and the number of the LEDs  31  can be plural to meet the needs of desired lighting performance, and the LEDs  31  can be mounted with SMD technology or other techniques of mounting to serve as a light source. Further, the cover  50  is coupled to the fin base  10  and the coupling between the cover  50  and the fin base  10  is realized through fitting or threading engagement so as to securely fix the cover  50  and the fin base  10  together. The cover  50  can be molded with a moldable material or made of glass. The moldable material is preferably plastic materials or the likes. The cover  50  can be shaped as a sphere so that the cover  50  may provide a large illumination area and form an improved expansion angle of lighting. In another alternative form of the present invention, the fin base  10  is extended to form, in an integral form, a shaped hood  12  (see  FIG. 5 ), and the hood  12  is integrally formed with the fin base  10 . The hood  12  can be formed as an extension of heat dissipation fin  101  or assumes any other configuration, so as to provide diverse variation of configuration of the hood  12 . Further, through the extension of the hood  12 , heat dissipation is improved. Thus, multiple functions are provided. 
     In summary, the present invention offers the following advantages: 
     (1) With the structure of the LED lighting bulb provided herein, advantages of easy disassembling, easy maintenance, and reduction of cost can be achieved and environmental conservation can be realized to thereby enhance practicability thereof. 
     (2) With the shaped hood extending from the fin base, variation of the configuration can be easily made and heat dissipation improved, thereby enhancing the convenience thereof.