Patent Publication Number: US-2006017364-A1

Title: Compact fluorescent lamps

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to the area of fluorescent lamps. Particularly, the present invention is related to a compact fluorescent lamp enclosing a ballast in a manner that the overall size of the lamp is significantly reduced and the method for making the same.  
      2. Description of the Related Art  
      Fluorescent-based energy saving lamps have been used widely in residential and industrial lightings because of their high efficiency in light outputs and energy. Moreover, these types of lamps are being highly promoted by the government.  
       FIG. 1  shows a structure for a traditional fluorescent lamp. As shown in the figure, the lamp includes a lamp base ( 1 ), a housing ( 2 ) and a lamp tubes ( 3 ). The housing ( 2 ) includes a housing cover ( 2 A) and a housing space ( 2 B), wherein the housing cover ( 2 A) and a housing space ( 2 B) form a chamber to embed a ballast therein. The tubes ( 3 ) are constructed on top of the housing cover ( 2 A) in multiple shapes such as U-shaped, Π-shaped or spiral shaped.  
      One of the issues in the structure of the traditional fluorescent lamp is the inherent size because the base( 1 ), housing ( 2 ) and tubes( 3 ) are connected directly in a line with the embedded ballast in the housing ( 2 ). Based on the current manufacturing technology, an electronic ballast is quite large in size. Therefore the size of the housing ( 2 ) is subject to that of the ballast. As a result, the housing ( 2 ) contributes significantly to the overall size or length of the lamp. Essentially the housing in the traditional fluorescent lamp restricts the compactness of a fluorescent lamp, especially in those lower power or shorter tube lamps, and becoming a barrier for further miniaturization and compactness of low power and energy saving fluorescent lamps. There is thus a need for energy saving fluorescent lamps in compact size. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The present invention will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements, and in which:  
       FIG. 1  shows a structure for a traditional fluorescent lamp; and  
       FIG. 2  shows a cross-section view of a fluorescent lamp in accordance with one embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      The present invention pertains to techniques of designing compact fluorescent lamps and a method for doing the same. According to one aspect of the present invention, instead of embedding a ballast in a chamber between a lamp base and lamp tubes, the ballast is enclosed in a space formed by the lamp tubes. As a result, the overall size of a fluorescent lamp is reduced. Fluorescent lamps manufactured in accordance with the present invention appear more compact. In one embodiment, the fluorescent lamps appear closer to the traditional incandescent lamps.  
      Reference herein to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.  
      Embodiments of the present invention are discussed herein with reference to  FIG. 2  that is provided for illustration and to facilitate the understanding of the present invention. However, those skilled in the art will readily appreciate that the detailed description given herein with respect to these figures is for explanatory purposes as the invention extends beyond these limited embodiments.  
      Referring now to  FIG. 2 , there shows a cross-view of an exemplary embodiment of a fluorescent lamp according to the present invention. As shown in  FIG. 2 , the fluorescent lamp includes a lamp base ( 10 ), a tube holder ( 20 ), lamp tubes ( 30 ), and a ballast ( 40 ). In one embodiment, the lamp base ( 10 ) is designed identical to that of an incandescent lamp and can be plugged or screwed in a traditional lamp socket to receive electricity to drive the lamp.  
      The lamp base ( 10 ) is connected to the tube holder, and the tubes ( 30 ) are mounted on top of or supported by the tube holder ( 20 ). In particular, the tubes ( 30 ) are structured and mounted in such a way that a space ( 50 ) is formed by the tubes ( 30 ). The ballast ( 40 ) is positioned in the space ( 50 ) and supported by the tube holder ( 20 ). One of the important features in the present invention is that the ballast is positioned in a space formed by the tubes such that the size, especially the length, of a fluorescent lamp is significantly reduced.  
      The tubes may be structured in a number of shapes to form a space in the middle that is large enough to accommodate the ballast. One example of the shapes is of spiral, in which tubes are wound around the space. The present invention has numerous advantages, benefits and features. One of them is the overall reduced size of a fluorescent lamp by positioning a ballast in a space formed by the light tubes. Another one of them is that a fluorescent lamp designed in accordance with the present invention makes the fluorescent lamp look closer to an incandescent lamp and fit more easily in a conventional socket for an incandescent lamp.  
      The present invention has been described in sufficient details with a certain degree of particularity. It is understood to those skilled in the art that the present disclosure of embodiments has been made by way of examples only and that numerous changes in the arrangement and combination of parts may be resorted without departing from the spirit and scope of the invention as claimed. For example, the ballast may be partially in a chamber space and partially in the space formed by the tubes, which still reduce the overall size of the lamp. Accordingly, the scope of the present invention is defined by the appended claims rather than the forgoing description of embodiments.