US2318072A - High intensity fluorescent lamp system - Google Patents

Description

May 4, 1943. w. c. HALL, JR 2,318,072

HIGH INTENSITY FLUORESCENT LAMP SYSTEM Filed sept. 24, 1941 Patented May 4, .1943

man .nv'raNsrrrYgnUonsscaNr Willard C. Hall, Jr., Los Angeles, Calif., assgnor to Alfred P. Daniels, Los Angeles, Calif.

Application September 2i, 1941, Serial No. 412,124

6 Claims.

This invention relates to a system for safely increasing the illuminosity of gaseous electric discharge lamps and the like. Itis especially useful forintensifying the illumnosity of fluorescent type lamps having end electrodes or cathodes which are heated to increase the flow of electrons. At present, the cathodes of such tubular. lamps operate at a given current density which forms a single hot or glow spot; the character and heat of this spot largely determining the life of the lamp. ,Should more than the rated current pass through the cathode, the hot spot thereof becomes too intenseiand the filament rapidly deteriorates and breaks.

This'invention intensifies the illuminationof standard gaseous electric discharge types of lamps by forming a plurality of hot or glow spots on the cathodes. By forming a plurality of hot 'nating device and the character 2, the transspots, each hot spot does not become overheated and the lament, therefore, does not rapidly deterlorate thus eachl cathode safely operates at greater electronic capacity.

This invention intensies the illumination of standard gaseous electric discharge types of4 lamps y by forming a plurality of hot or glow spots on the cathodes. The hot spots do not tend to merge and the lament is not in any way impaired. Instead of the lamp having al1 its lighting energy emanating from a single spot upon the cathode, a plurality of such spots supply the energy at a low temperature and forms a greater column of light giving properties throughout the active length of the lamp. An object of this invention is to present an electrical system for greatly increasing the illumination of gaseous electric discharge lamps without shortening the useful life thereof.

Another object is the provision of a transformer device which is capable of forming a plurality of hot spots on a single cathode.

Still another object is to provide an electrical system for standard gaseous electric discharge lamps which forms a plurality of hot spots on their laments for materially increasing the einciency thereof at a high power factor; this being accomplished by a simple sturdy device economical to manufacture.

Other objects. advantages and features of my invention will appear from the accompanying drawing, the subjoined detailed description, the

preamble of these specications and the appended claims.

Applicant is about to illustrate and describe one of the forms of his invention in order to teach one how to make, use and vend the same, but it is to be understood that the drawing and description thereofare not to limit the invention in any sense whatsoever, except as limited by the appended claims.

In the' drawing:

Fig. l shows a wiring diagram of the invention.

Fig..2 shows in elevational view, parts being' broken away, of a switch adapted lfor use in the invention. y

,The reference character t indicates the illumisformer. The illuminating device in the drawing is a glass tube or envelope having at its ends the glass presses 3 and through which pass the conductors 5 and E, and the conductors l and 8 respectively. Within the envelope are the electrodes or thermionic cathodes 9 and l0 in the `form of coiled filaments having their ends connected across the lead in conductors at their respective ends of the tube. The tube is lled with nated limbs, a large'area central limb Il upon tov and the other end to conductor 1. Shunting the coil Il are the switchA 2l having leadsl2l' and 2|" and the condenser 22 with its leads 22' and 22". The other secondary coil has one end connected to the conductor 6 which leads to the cathods 9, and the other end of which that connects with the conductor 8;-the conductor 8 leading to the other cathode I0.

The instantaneous polarity of the'secondary coils are indicated, and' show that the instantaneous positive polarity of each coil is connected across one of the electrodes and the instantaneous negative polarity of each coil is connected across the'other electrode. Therefore, when an alternating current; for instance,

at an impressed line voltage of and frequencyof 60 cycles, is connected to the primary l2 through switch I4', like voltages and polarity, at any given instant, is impressed across one of the electrodes, and the Vopposite polarity across the other electrode. 'I'his is the case when the tube is in 'normal operation by electronic bombardment. Y

To start the tube, the switch 2l and condenser 22 must function so as to ilrst heat the cathodes and provide the higher voltage surge to strike the tube. The switch 2l may be ofthe gaseous electric discharge type now to be described, or it may be of the type that is closed when cold and open when hot. Y

In Fig. 2 of the drawing, a gaseous electric dis charge switch is shown which is especially adapted for use in this invention. lI'he switch has a casing or envelope 2l which may be of glass or metal, and has the glass press or seal 28 which give support to the two bixnetal strips 29 and 30, the strips having connection with the wire conductors 2|' and 2i" as shown in Fig. l. One of the strips has a curled contactor 3| and the other strip has a plate contact/or 32. The envelope is iilled with any suitable ionizable gas such as neon. When current at proper voltage is connected across the leads of the switch, an electric discharge will take place between -the strips 29 and 30 and heat them. Upon heating,

the strips will flex toward each other and their ends make contact to close the circuit; contacti havingbeen made, the switch strips 2S and 30 cool and separate and thus open the circuit to which they are connected. This switch when closed, at the start of operations, short circuits the coil I1 and thus doubles the power out-put and voltage of coil i8 which is then in series with both electrodes and provides the current to heat these electrodes. When the laments of these electrodes become hot, the switch 2| automatically opens (a matter of a few seconds) and connects like polarity ends of both coils to their reu spective electrodes. Immediately, the electrodes have opposite polarity at any instant, and are maintained at operating heat by electronic bombar'dment alone.

By the arrangement of this new system, two

- hot spotsform on each electrode at their ends as indicated by the numerals 23, 24, 25 and 2B. `These spots form conductive gas columns in the tube which merge to form an intensified prin-4 ciple conductive column which extends themajor length'of the tube. The spots on each electrode do not tend to unite due to the resistance along the lament being greater than the ionized gas column. 'Ihis action means that it is possible-to run the tube at twice its normal current capacity and hence obtain nearly twice its nor- 2,s1s,o7a

1. In combination, a gaseous electric discharge lamp with end cathodes and a transformer, the

. transformer having a primary coil, and secondary windings substantiallyin phase with theirv like polarity ends connecting across one cathode and the other opposite like polarity ends connected across the other cathode, and switch means connected across one of the windings to short it when the lamp is started. i

2. In combination, a, gaseous electric discharge lamp with end cathodes and aitransformer, the transformer having windings substantially in phase with their like polarity ends connecting across one cathode and their other opposite like polarity ends connected across the other cathode, a switch and condenser having leads connecting opposite ends of one of the windings, the switch operating to short the winding when closed, and

a primary coil for energizing they windings. l

3. In combination, a gaseous electric discharge lamp with end electrodes and a transformer, a primary winding for supplying power to the transformer, a pluralityof secondary coils, the ends of the coils having like polarity connecting across one of the electrodes and the other ends of the coils connecting across the other electrode, switch means for short. circuiting one of the-coils to allow the other coil to heat the electrodes in series.

4. In combination, a, gaseous electric discharge lamp wih end cathodes and a transformer having three limbs, a'primary winding on one of the limbs having connection to a source of electric current, a secondary coil on each of the other two limbs, a conductor from one end of each coil connected across one of the cathodes and another-conductor from the opposite end o1 each coilconnected across the other cathode, a switch connected across one of the coils for the purposes described.

5. The method of forming a plurality of hot spotson the cathodes oi' a gaseous electric disi charge lamp by: providing across each cathode mal brilliancy without injury to the cathodes or i a like instantaneous polar voltage and maintaining the cathodes in opposite 'instantaneous polarities with respect to each athen-and maintaining the spots on the cathodes separated by maintaining a lower resistance between the cathodes then between the spots.

6. In combination, a gaseous electric discharge lamp with a plurality of electrodes and a transformer having a primary coil and4 secondary windings, two of the electrodes each including a filament having spaced apart'hot spots, one of the filaments having its ends connected across like polarity parts of said windings and the other filament having its ends connected across the opposite like polarity parts of the windings, and switch means connected across one of the windings to short it when the lamp is started, the shorting of said one of the windings connecting the other winding in series with said filaments.

.wILLARp c. HALL. JR.

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