Lamp base with flexible sidewall

Information

  • Patent Grant
  • 6255763
  • Patent Number
    6,255,763
  • Date Filed
    Tuesday, October 12, 1999
    24 years ago
  • Date Issued
    Tuesday, July 3, 2001
    22 years ago
Abstract
An insulating member for a base for a light emitting bulb has an electrically insulating body formed from a thermoplastic plastic material and having a first surface, a second surface spaced therefrom, and a sidewall connecting the first and second surfaces. The sidewall is formed to flexibly receive and hold an electrically conductive element, such as the threaded portion of a screw base.
Description




TECHNICAL FIELD




This invention relates to electric bulbs and more particularly to bases therefore.




BACKGROUND ART




Electric bulbs, particularly those of the kind employing any of various sizes of Edison bases, i.e., the common threaded base, have a three-part base comprising an electrically conductive eyelet portion and an electrically conductive threaded portion separated and held together by a glass insulator. Such bases are manufactured on automatic equipment, which utilizes a glass furnace for forming the insulator and connecting the separated electrically conductive pieces. These bases are made literally by the billions each year and provide a substantial part of the cost of many light bulbs. The cost of heating and melting the glass, as well as the cost of maintaining the glass furnace contribute to the cost of the bases. Accordingly, it would be an advance in the art if a base could be produced at a lesser cost.




DISCLOSURE OF INVENTION




It is therefore, an object of the invention to obviate the disadvantages of the prior art.




It is yet another object of the invention to enhance the manufacture of bulb bases.




Still another object of the invention is the provision of a new method of making bulb bases.




Yet another object is the elimination of the glass insulator from the base.




These objects are accomplished, in one aspect of the invention by providing an insulating member for a base for a light emitting bulb which comprises an electrically insulating body formed from a thermoplastic plastic material and having a first surface, a second surface spaced therefrom, and a sidewall connecting said first and second surfaces, said sidewall being formed to flexibly receive and hold an electrically conductive element.




In another aspect of the invention, a base for a light emitting bulb comprises an electrically insulating body formed from a thermoplastic plastic material and having a first surface, a second surface spaced therefrom, and a sidewall connecting the first and second surfaces. The sidewall is formed to flexibly receive and hold an electrically conductive element. An electrically conductive eyelet is affixed to the first surface while the electrically conductive element extends beyond the second surface. The electrically conductive element has a first end formed with a reentrant portion having a terminal end in contact with the sidewall.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is an elevational sectional view of an embodiment of the invention;





FIG. 2

is an enlarged, perspective view of a portion of the insulating body of the invention; and





FIG. 3

is a perspective view of the terminal end of the electrically conductive element.











BEST MODE FOR CARRYING OUT THE INVENTION




For a better understanding of the present invention, together with other and further objects, advantages and capabilities thereof, reference is made to the following disclosure and appended claims in conjunction with the above-described drawings.




Referring now to the drawings with greater particularity, there is shown in

FIG. 1

a base


10


for a light emitting bulb that comprises an electrically insulating body


12


formed from a thermoplastic plastic material, for example, polyethylene, and having a first surface


14


, a second surface


16


spaced therefrom, and a sidewall


18


(see

FIG. 2

) separating and connecting the first and second surfaces. The sidewall is formed to flexibly receive and hold an electrically conductive element


20


, which can be the threaded portion of a screw base. The flexible portion comprises a groove


22


on the outside of sidewall


18


and a channel


24


formed in second surface


16


. The groove


22


and channel


24


cooperate with alternating slots


26


and retention protuberances


28


that are formed on a free surface


30


of receiving groove


22


.




Electrically conductive element


20


(see particularly,

FIG. 3

) has a reentrant portion


32


having a terminal end


34


that fits into receiving groove


22


. The edge


36


of terminal end


34


is provided with slots and ribs


38


,


40


, respectively, that cooperate with the retention protuberances and slots


28


and


26


that are formed on the free surface


30


. This not only locks the element


20


onto the insulating body


12


but also prevents rotation of the element


20


with respect to the body


12


.




The now completed base can be assembled to a bulb


40


containing a light emitting element such as an incandescent filament, an arc tube, a light emitting diode array, an electroluminescent display or other device. In the case of a bulb containing an incandescent filament, at least two lead-in wires


42


and


44


exit the bulb


40


and are attached, respectively, to an eyelet


46


affixed to the first surface


14


and the element


20


.




Thus there is provided a new base for a light emitting bulb that is economical to manufacture , primarily due to the elimination of the glass insulator and its glass-melting furnace.




While there have been shown and described what are at present considered to be the preferred embodiments of the invention, it will be apparent to those skilled in the art that various changes and modification can be made herein without departing from the scope of the invention as defined by the appended claims.



Claims
  • 1. An insulating member for a base for light emitting bulb comprising: an electrically insulating body formed from a thermoplastic plastic material and having a first surface, a second surface spaced therefrom, and a sidewall connecting said first and second surfaces, said sidewall being formed to flexibly receive and hold an electrically conductive element.
  • 2. The insulating member of claim 1 wherein said sidewall has an electrically conductive element receiving groove formed therein.
  • 3. The insulating member of claim 2 wherein said second surface has a circumferential channel formed therein.
  • 4. The insulation member of claim 3 wherein a free surface of said receiving groove is formed to provide alternating slots and retention protuberances.
  • 5. A base for a light emitting bulb comprising: an insulating member in accordance with claim 2; an electrically conductive eyelet affixed to said first surface; and an electrically conductive element extending beyond said second surface, said electrically conductive element having a first end formed with a reentrant portion having a terminal end in contact with said sidewall.
  • 6. The base of claim 5 wherein said terminal end is formed with alternating slots and ribs which cooperate with slots and retention protuberances formed on said receiving groove.
US Referenced Citations (6)
Number Name Date Kind
2336529 Cartun Dec 1943
2403137 Strickland Jul 1946
4654557 Haraden Mar 1987
4658178 Bradley et al. Apr 1987
5382869 Williamson et al. Jan 1995
6036522 Holzer Mar 2000