US2482277A - Electric arc discharge circuits for illuminating devices - Google Patents

Description

Sept. 20, 1949. c 1 JAUSS ELECTRIC ARC DISCHARGE CIRCUITS FOR ILLUMINATING DEVICES Filed Jan. 17, 1947 F/G. l

WWW mu Li Patented Sept. 20, 1949 UNITED STATES PATENT OFFICE ELECTRIC ARC DISCHARGE CIRCUITS FOB ILLUMINATING DEVICES Carlos L. J auss, New York, N. Y.

Application January 17, 1947, Serial No. 722,597

6 Claims.

heating the cathodes and initiating the discharge when the lamps are to be operated by low voltages. For such pre-heating of the cathodes various starting switches have been employed while the limitation of lamp current has been generally effected by means of a ballast, usually an iron core choke coil. Such a ballast choke further.

It is generally considered that most satisfactory lamp operation is obtained when about half the available voltage appears as the voltage drop in the arc of the fluorescent lamp during operation while the other half appears as the voltage drop across the ballast. It is well recognized that the current consumption by the ballast, which is a reactor, introduces a power factor in the electrical circuit which complicates the electrical equipment feeding the lamp. Furthermore, the ballast comprising as it generally does laminations, has a tendency to chatter at the frequency of the applied current and often generates considerable heat within itself. In fact, the degree of heat is often such that the ballast cannot be held in the hand.

Bearing the foregoing in mind, it is an object of the present invention to provide a ballast for a lamp of the above type in which the generation of heat is rendered unobjectionable in that concentration thereof is avoided. Allied with this object is the provision of such a ballast where the means supplying the inductive kick generates substantially no heat at all.

Another object of this invention is to provide a ballast of the type disclosed which is noiseless in that no laminations are incorporated therein which may cause chattering.

Still a further object of this invention is the provision of a ballast which can most easily be incorporated in a line cord and plug while having substantially no effect on the physical form of the line cord and adding so little material and weight to the plug that the plug can be conveniently inserted in a socket while supporting a reactor. The combination plug and reactor is thus of such lightness that the socket can most 2 easily sustain it, a condition which is considered highly desirable in the industry.

Other objects of my invention include the provision of a ballast with improved power factor operation, economical construction, and wherein the assembly of the device with a line cord or plug ofiers considerable economical advantages.

Other objects of my invention will be apparent from the following description, it being understood that the above general statements of the objects of my invention are intended to describe and not limit it in any manner.

Referring to the drawings:

Fig. 1 is a schematic view illustrating one adaptation of my invention.

Fig. 2 is a view similar to Fig. l and illustrating the incorporation of the reactor into the plug of the circuit.

Fig. 3 is a top plan view of the reactor and line cord combination as shown in Fig. 2, the cover being removed.

Fig. 4 is a cross sectional view along the lines 4-4 of Fig. 3.

Fig. 5 is an elevational view of one conductor of the line cord over which is wound a resistance element.

In the drawing, l0 represents an electric discharge lamp such as of theiiuorescent type which comprises a transparent tubular envelope having a filling of rare gas, or metal vapor, or both. The envelope is provided at its ends with cathodes I I and 12 of the usual type. Such cathodes may be heated directly as illustrated or indirectly as is.

well known in the art. The lamp is connected through line conductors l3 and I 4 to the voltage source which is generally or 230 volts of alternating current. Conductors l5 and I6 serve tov connect the cathodes to a starter device H, the starter being of a well known construction such as that of the glow discharge or thermal-switch type, either being used to pre-heat the cathodes and then promptly open the circuit, although.v

manual starters of any well known type may well be employed.

In order to provide the impedance required for the ballast, I provide the combination of a line cord resistance and a simple air core reactor.

accomplish the desired ohmic resistance.

' nected in series with resistance I8 is the reactor winding l9 enclosed in the case 20. Resistance I8 is operatively connected to a prong 2| of plug 22 so that the ballast represented by resistance l8 and reactor I9 is in series with the fluorescent connected to pron 2| as is resistance I8, is not connected to conductor M as otherwise it would v short-circuit the resistance [8 as is evident. The function as casing '20 but it is further provided resistance l8 may, of course, be wound around the opposing line conductor [3 and be connected to the prong 2| as shown in w'hich case portion I4a may be eliminated.

.for the resistance. Portion 14a, while it may be conductors are substantially identical with that.

The action of resistor i8 and reactor l9 in con stituting a ballast for the lamp is well understood in the art. "'Ihecombined ohmic values of resistance 18 and reactor 19' serve to limit the operating current to lamp while reactor 19 supplies an inductivekick which produces-a high initiating voltage after starter H has completed its heating of the cathodes and hasbroken the circuit. '1"

' Reactor [9 is, according to the instant invention, of the air core type and comprises a plurality of coil turns wound around a tubular paper or Bakelite form 25. In actual practice, I have utilized about 10 layers of'No. 29 -gauge enamel insulated ,magnet ,wire; each layer comprising approximately 50 turns of 1 inch diameter. 7 The innermost layer surrounding the form 'was approximately inch in diameter so as'to permit the insertion therethroughof form 25. It is to' be understood that whereas I have referred to the diameter of'the reactor winding,- the actualform thereof is not necessarily circular. ,As illustrated in Figs. 3 and 4, the windin is rectangular although its dimensions may be'such that its perimeter approximates thediarneter values above mentioned. Each layer of reactor l9 may be separated by the usual fish paper or the like and a cover 26 of adhesive tape may firmly enclose the layers. In order to maintain reactor is securely in place and to provide terminal means therefor. end members 21 and 28 are'inserted over form 25 so as to be frictionally' held thereby'and the ears 29 and 30 may serveas terminal posts for the respective ends of the reactor winding. Resistance I8 is then connected to one of said terminal postswhile conductor I4 is connected to the other one.

' It will be observed that the line cord conductors l3, portion 14a of conductor I4, and resistance l8 enter the casing 211 through an opening formed in a wall thereof and thereafter travel through the hollow of form 25 so asto serve for a support for the reactor winding constituting the required inductance Such construction constitutes a most economical and simple arrangement, afiording considerable manufacturing advantages. This is possible because reactor 25 does not include the usual core laminations which would prevent such an assembly; Of course, laminations may be provided between the outer surface of form 25'jand the coil layers, but it is preferred in the instant. inventionthat the reactor has an air core as described.

Casing 20, which houses the reactor, requires no pitch or other substance, for securing the re.-

actor within the casin I a muc as ac r 19 includes no lamination's, it' does not chatter, it is noiseless, and no such binding substances are necessary. Furthermore, the heat generated by the resistance is dissipated over an extended area to avoid any concentration thereof. Casing '20 is provided with a suitable cover, not shown, but

of the general type illustrated in the following embodiment.

In the embodiment of Fig. 2, the resistance 35 and the reactor 36 are ofthe'sam'e form and value described in' the previous embodiment "and they are likewise in serieswith the fluorescent lamp circuit during operation thereof. The casing 31 serves substantiallythe same reactor enclosing with prongs i8 and 39 supported by its cover 40. The disposition of the reactor, resistance and line illustrated in Fig. 3. Thus, the resistance supporting portion 4| of the line conductor actually penetrates the air core of reactor 36 beforeit is connected to prong 38 .while'the line conductor 42- maysimilarly traverse the core and be brought around the outside of the reactor to effect;

the connection illustrated through terminal posts as hereinabove described:

v In this second embodiment, the casing 31 itselfmay be plugged into an appropriate 'electrical outlet whereby the current willbe applied to-the lamp as required. No other casin or auxiliaryequipment is needed. The ca'sing 31, housing as it does the extremely light-reactor 36 supportedby the line conductorsthemselves is of an overall lightness which permits it to be held securely in a socket without injuring or bending the ele-' ments thereof. The tendency ofsuch a plug to fallv from'the socket dueto its weight is further minimized so that no additionalprecautions such as prong locking devices need be employed.

' In either 'embodiment th'e resistance may be wound around a line'conductor as illustrated in Fig. 5 herein.. In a typical embodiment, thein ductance of reactor 19 was approximately 12 millihenrys. was combined with line cord resistances of 150 ohms, 1"96 ohms, 196 ohms and 450 ohms respectively where the lamp wattages were 20 watts, 'lfi-watts, 14'watts and' 6 watts. "In" any low watt lamps such as 6 watts'or 4 watts; the

reactor insures that .a sufficient inductive kick is produced to initiate the arc.

It is recognized that the predominating-resistance in a resistance-reactor combination circuit produces energy losses *in' proportion to the predominance of resistance to inductance. However, the-power ia-cto'rpf the circuit is increased considerably-and otheradvantages accrue such as set forth above. The-arrangement shown'is' 7 further suitable for alternating currents of various cycles, such as either 60, 50 or '25 cycles, and no particular modification of the circuit elements is required to adap't them to thefrequency 'of' such currents. V V

The elongated resistance or without the reactor has special merit in a lamp circuit such as described. This is attributable to the fact that for resistor ballastswenclosedin a casing. This rendersthe panastveryni uana "unduly large and in general embodies such disadvantages as are eliminated by the instant construction.

It is further to be noted that whereas I have illustrated the resistance as being wound around a line conductor, it is not essential that this construction be adhered to since it is feasible to include an elongated resistance anywhere in the circuit. In fact, a resistance having an asbestos core and an asbestos jacket with suitable braiding may be enclosed within the fixture which supports the lamp Iii. Such fixtures are well known and are widely used and serve the purpose of supporting the lamp while supplying sockets therefor whereby the current may be fed to the lamp terminals. the fixture, being metallic, could further serve to dissipate over an extremely large area the heat generated by the elongated resistance which may be arranged within the fixture so as to utilize a considerable portion of. its area. In this manner, the generation of heat, already minimized by the elongated resistance, is further rendered less objectionable by its distribution over a large area through the inherent operation of the fixture.

Thus, there have been shown above what at present are considered preferred embodiments of the invention. It will be obvious that many changes and modifications are possible without departing from the scope thereof. For example, the actual construction of the reactor, such as the number of turns and other details, may be varied as required. Therefore, it is intended in the following claims to cover all such changes and modifications as fall within the true spirit and scope of the invention.

I claim:

1. Ballast means for an electrical gaseous discharge device including line conductors for feeding alternating current to the device, said ballast means comprising a resistance extended aiong a substantial length of at least one of said line conductors so as to dissipate any heat generated thereby over an extended area, and an air core inductance, both said resistance and said air core inductance adapted to be connected in an electrically series relationship with said device, said line conductors supporting said air core inductance by extending through the core thereof, the ohmic value of said resistance greatly exceeding the ohmic value of said inductance when said alternating current is flowing through said series related elements.

2. The combination of ballast means with current feeding means for an electrical gaseous discharge device operated on alternating current, said current feeding means including line conductors for feeding the alternating current to the device, said ballast means including an air core inductance adapted to be connected in an electrically series relationship with said device, said air core inductance being supported by at least one of said line conductors by having said one line conductor extending through the air core of said inductance.

3. The combination of ballast means with current feeding means for an electrical gaseous discharge device operated on alternating current,

In such a construction 7,

said current feeding means including line conductors for feeding the alternating current to the device, said ballast means including an air core inductance adapted to be connected in an electrically series relationship with said device, a casing for enclosing said air core inductance, said line conductors entering said casing through an opening formed therein and extending through the air core of said inductance so as to support said inductance within said casing.

4. The combination of ballast means with current feeding means for an electrical gaseous discharge device operated on alternating current, said current feeding means including line conductors for feeding the alternating current to the device, said ballast means including an air core inductance, a casing enclosing said air core inductance, said line conductors entering said casing through an opening formed therein and extending through the core of said air core inductance so as to support said inductance within said casing, one of said line conductors being connected to said air core inductance within said casing whereby said inductance may be included in an electrical series circuit with said device, and a pair of prongs formed on said casing whereby said casing may be plugged into an electrical outlet for supplying current to said device.

5. The combination according to claim 4 and wherein said ballast means further comprises a resistance extended along a substantial length of at least one of said line conductors so as to dissipate any heat generated thereby over an e?- tended area, the ohmic value of saidv resistance greatly exceeding the ohmic value of said air core inductance when the alternating current is flowing in said series circuit.

6. The combination of ballast means with current feeding means for an electrical gaseous discharge illuminating device, said current feedin means including line conductors for feeding electrical current to the device, said ballast means comprising an elongated resistance extending along said line conductors, said resistance being operative to dissipate any heat generated thereby over an extended area, an air core inductance in series with said resistance, a casing for housing said inductance and a pair of prongs formed on said casing whereby said casing may be plugged into an electrical outlet for supplying current to said device.

CARLOS L. JAUSS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,971,940 Pirani Aug. 28, 1934 1,984,489 Mutsaers Dec. 18, 1934 1,990,175 Foulke Feb. 5, 1935 OTHER REFERENCES Electric Discharge Lamps, H. Cotton, Chapman and Hall Ltd, 37 Essex St., W. C. 2, 1946, p. 236.

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