CA1204145A - Fluorescent lamp - Google Patents

Abstract

FLUORESCENT LAMP

ABSTRACT

A fluorescent lamp having parallel legs has a combination leg support and starting aid which includes metal sleeves on each leg adjacent the electrodes. The sleeves are connected together by a rigid rod-like member.

Description

D-23,989 ~æ~4~s _ 1 _ FLUORESCENT LAMP

TECHNICAL FIELD

This invention relates to fluorescent lamps and more particularly to such lamps having parallel legs and including a starting aid.

BACKGROUND ART

Fluorescent lamps can be viewed as substantially linear light sources when compared with incand~scent lamps which are sustantially point sources.
10To maintain the same amount of light in a more compact configuration, fluorescent linear tubes are sometimes formed into convoluted shapes, such as circular and "U" shapes.
It is common in "U" shaped, energy saving lamps to employ a starting aid in the form of an electrically conductive, transparent coating applied to the interior surface of the bulb wall. Also employed are supporting structures affixed bet~een the legs of the lamp, between the bases. 5uch a latter arrangement is shown in U.S.
Patent No. 3,579,l74.
The application of the internal conductive coating is expensive and requires extra manufacturing steps, and it is believed the elimination thereof would be an advance in the art.

DISCLOSURE OF INVENTION

It is, therefore, an object of tne invention to obviate the disadvantages of the prior art.
25It is another object of the invention to enhance fluGrescent lamps.
Yet another object of the invention is the reduction in cost of fluorescent lamps.
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D-23,98~ 5 .. -2-These objects are accomplished, in one aspect of the inventi~n, by the provision of a fluorescent lamp which has two, substantially parallel, spaced apart legs terminating in closed ends. Each of the closed ends has an electrode sealed t~erein. A cornbination leg support and starting aid is attached to the legs and extends therebetween. The leg support and starting aid comprise an electrically conductive sleeve at least partially surrounding each leg of the lamp in a position adjacent the electrode. An electrically conductive, substantially rigid rod-like member is fixedly connected to each of the sleeves.
The supportive function of this member adds to the mechanical strength of the legs and maintains the ends of the lamp a set distance from one another. The location and configuration of the sleeves provides the starting aid function and eliminates the need 15 for the internal conductive coating.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of one leg of a prior art lamp;
FIG. 2 is an elevational view of a larnp employing the invention and FIG. 3 is a sectional view taken along the line 3-3 of FIG. 2.

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 clairns 25 taken in conjuncton with the above-described drawings.
Referring noh to the drawings with greater particularity, there is sho~n in FIG. 1 a cross-section of a prior art fluorescent lamp having a tubular glass envelope 10 having on its interior surface a transparent, electrically conductive coating 12 which functions as a starting aid. A layer of phosphor 14 is applied over the conductive layer 12.

D-23,'389 ~4~5 Referring now to FIG. 27 there is shnwn a fluorescent lamp 16, according to one Pmbodiment of the invention, hav;ng two substantially parallel, spaced apart legs 18 and 20 which terminate in closed ends 22 and 24. The ends can be provided with appropriate bases 26 and 28.
Each of the ends 22 and 24 has sealed therein an electrode 30 and 31 respectively which can be tungsten coils containing an electron emissive material as is known in the art. The interior surface of the legs, as well as the bight 33 which connects them, is coated with a phosphor 35.
A combination leg supporting means and starting aid 32 is attached to the legs 18 and 20 and extends therebetween. Means 32 comprises electrically conductive sleeves 34 and 36 which at least partly surroun~ the legs 18 and 20 of lamp 16. A substantially rigid, electrically conductive, rod-like member 38 is fixedly connected to the sleeves 34 and 36, as, for example, by welding.
The sleeves 34 and 36 are preferably semicircular in configuration. When desired, the sleeves can be fabricated from a flexible material and encompass more than 180 of arc, as shown in FIG. 3, and be held in place by frictional and compressional forces against the wall of legs 18 and 20.
Alternatively, the sleeves can be cemented or epoxied ir position. Further, the sleeves can be completely circular and placed in position by sliding them over the ends 22 arld 24 of legs 18 and 20.
Regardless of the configuration of sleeves 34 and 36 they are fixed in a position substantially adjacent the electrodes 30 and 31 as is shown in FIG. 2.
While not limited thereto, the starting aid described above is particularly applicable to fluorescent lamps employing a krypton fill.
Thus, there is llerein provided a combination leg support and starting aid which provides the necessary functiorls and eli~inates the internal conductive coating previously used. Since th~ latter coating, no matter llow transparent, must inherentl~ absorb sonle of ~-~3,90~
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the light emitted by the phosphor, larnps employing the invention described herein~ everything else being equal, will be brighter than those lamps having the coating.
While there have been shown and described what are at pres~nt S considered to be the preferred embodiments of the lnvenkion, it will be apparent to those skilled in the art that Yarious changes and modifications can be made herein without departing from the scope of the invention as defined by the appended claims.

Claims (5)

1. A fluorescent lamp having two, substantially parallel, spaced apart legs terminating in closed ends; an electrode sealed in each of said ends; and a combination leg supporting means and starting aid attached to said legs and extending therebetween; said supporting means and starting aid comprising an electrically conductive sleeve at least partially surrounding each leg in a position adjacent said electrode and a substantially rigid, electrically conductive, rod-like member fixedly connected to each of said sleeves.

2. The lamps of Claim 1 wherein said legs are tubular and said sleeves are semicircular.

3. The lamp of Claim 2 wherein said sleeves encompass an angle greater than 180°.

4. The lamp of Claim 3 wherein said sleeves are relatively flexible and are maintained in position by frictional and compressional engagement with said legs.

5. The lamp of Claim 3 wherein said sleeves are cemented to said legs.