Патент USA US2135691код для вставки
' NOV- 8, 1933‘- H. ALTERTHUM ET AL 2,135,691 GASEOUS ELECTRIC DISCHARGE DEVICE Filed Dec. 2, 1936 INVENTORS Hans Al’cerHwum Marcello Pirani A ORNEY ' ?aten_ted Nov. 8, ii T33 rATENT OFFICE UNH'ED STATES 2.135591 GASEOUS ELECTRIC DISCHARGE DEVICE Hans Alterthum and Marcello Pirani, Berlin . Wilmersdorf, Germany, assignors to General Electric Company, a- corporation of New York Application December 2, 1936, Serial No. 113,919 , In Germany December 6, 1935 3 Claims. (01. 176-124) The present invention relates to gaseous elec- 1 the electrode at the other end of the tube; or trlc discharge devic generally and more par ticularly the inventio relates to such devices use-v ful as light sources (1 for advertising. 5 . The object of theR} vention is to provide a gase ous electric discha ge lamp out?t for operation on commercial sources of symmetrical alternating current which out?t comprises a gaseous electric . discharge device emitting different colored light 10 from di?erent parts thereof and which is useful in the advertising and illumination ?elds. Still furtherobjects and advantages attaching to the device and. to its use and operation will be ap parent to those skilled in the art from the fol _15 lowing particular description. . gaseous electric discharge device having a oi’- gases‘therein, which gases have dif- when cold electrodes are used one electrode is activated and the other is not, or when cold elec trodes of equal size are used in each end of the tube the tube is connected across a_high voltage 5 transformer which has an operating voltage -' slightly greater than the starting voltage of the tube and a particularly sensitive part of_the tube is grounded. The sensitive part of the tube is discovered by groping either with the bare hand 10 or with a grounded band. The assymmetry of the alternating current is equivalent to the super-' imposing of a direct current on the alternating current applied to the tube and has a like e?ect, that is, it causes the separation of the constituents 15 of the gas mixture so that one end of the tube emits a light typical of the gas collected thereat and the other end of the tube emits light typical ferent' ionizing potentials, emits di?erent colored of the different gas collected thereat. lighti'from‘idi?erent'parfs thereof when the de It is 'su?lcient for the purpose of the invention 20 if the separation of the gases in the tube proceeds the cathode-and the" gas having the higher ioniz- - only to that point whereat the gas having the ' ingpotentlial travels‘toward the anode under the lower ionizing potential is moved out of one part in?uence‘o‘of the direct current discharge. This of the tube. Since the gas having the higher .25 separation .of the gases is known in the art as ionizing potential is excited to luminescence by the discharge only in that, part of the tube con electrophoresis. and 'in pronounced cases in dis taining very little of the gas having the lower chargedevic'esa-having an elongated tubular con I tainer‘the tube has-the appearance of two linear ionizing potential the tube then emits di?erent colored light from different parts thereof. . luminescent'fcolumns of different color, for ex Preferably the tubular container of the device 30 :-.‘30 ample, when a mixture of'neon and argon is used is many times greater in length than in'diameter inthe tube? the device appears red at one end thereof and‘ blue-violetv at the other end thereof. and the diameter itself is preferably small. The When suehdevices are operated on symmetrical thermal diffusion of the gases in the tube, which alternating current this phenomena does not take tends to overcome'the separation of the gases 35 under the in?uence of the unsymmetrical alter 35 place because the tendency of the gases to sepa nating current, is thus minimized. Preferably rate during one‘ half cycle is overcome by the re versal of current ?ow in the next half cycle. It is, the percentage of gas having the lower ionizing of course, possible to cause the separation of the potential, for example, argon in an argon helium -20"vicej_'._is_.op'erated lonédirect current since the gas .vhaving-aa-‘lower ionizing potential travels toward _ gases in an alternating current device by super 40 imposing a direct current on the alternating cur rent, but such an apparatus is expensive and complicated. ' The present invention attains its objects by transforming in the lamp itself a symmetrical 45 alternating current supplied to the discharge de vice into. an unsymmetrical alternating current to a degree that separation of the constituents of the gas mixture takes place with the e?ect de scribed above. The transforming of the symmet 50 rical alternating current supplied to the tube into _ unsymmetrical alternating current can be ac complished in many di?erent ways, for example, when thermionic electrodes are used the elec trode at one end of the tubular container has a 55 di?erent electron emissive capacity than that of mixture, or mercury in a neon mercury mixture, is such that it is just su?icient to emit light. We 40 have observed that the smaller the amount of the component having the lower ionizing poten tial the faster is the separation of the gases in the tube. In the drawing accompanying and forming part of this speci?cation two embodiments of the in vention are shown, in which Fig. 1 is a side elevational view of one embodi ment of the invention, and Fig. 2 is a similar view of another embodiment 50 of the invention. . Referring to Fig. 1 of the drawing the gaseous electric discharge device comprises a tubular con tainer I having electrodes 2 and 3 sealed therein _ at the ends thereof and having a gaseous atmos- 55 arsenal phere therein. Said electrodes 2 and I are elec those museum artwithoutdeparting from tron emitting when heated to an elevated tem ' the broad spirit and scope of the invention, for _ perature by the eifects of the discharge incident thereat and consist oi’ a pellet of electron emit ting material, such as barium oxide, having a illament of high melting point material, such as tungsten, wrapped around said pellet. The elec trodes I and s are‘ selected so as to have different electron emissive capacity. The gaseous atmos 10 phere consists of a mixture of helium at a pres sure of approximately 8.7 mm. and argon at a pressure of approximately 0.3 mm. The tubular container I is about 7 mm. in diameter and the electrodes 2, 3 are separated a distance ‘of about 15 300 mm. When the lamp described above is con nected to a source of symmetrical alternating current a visible separation of the gas mixture takes place immediately after the discharge has started and the maximum separation of the con stituents takes place in approximately 30 seconds. emits light diiierent in color than the emitted by any of the gases in the tube, desired, a yellow ?uorescent material, zinc silicate, is applied to that part ofthe' E5 "the container surrounding the luminous mercury column of a device containing neon and mercury 10 vapor to obtain a light approximating white light. Whatweclaimasnewanddesiretosecureby Letters Patent of the United States, is: I. In combination. a cun'ent' source of sym metrical alternating current, a gaseous electric 15 discharge device connected across the terminals of said source, said device comprising an elon gated tubular container, electrodes saled therein at the ends thereoi’, a mixture of gasu therein each of said gases having a diiferent ionising N The discharge in the end of the tube whereat the . potential said electrodes being cold electrodes, the less emissive electrode is mounted appears yel low-rose in color and the discharge at the oppo site end of the tube appears blue-violet in color. A tube having this appearance is, of course, use ful for advertising purposes. When cold electrodes 5 and 6 are used a sensi tive part of the container i is connected to ground by band ‘I, as shown in Fig. 2 of the draw ing, and as disclosed above. - - . ‘ When the gaseous atmosphere comprises a voltage of said current source being slightly higher than the starting voltage of said device. a sensitive part of said device being grounded to transform the symmetrical alternating current as into‘ unsymmetrical alternating current in said device to cause said device to emit diiferent col ored light from different parts thereof. ‘ v 2. In combination a current source of sym metrical alternating current, a gaseous electric discharge device connected across the terminals metal vapor and a ?xed gas, such as a mixture 01' ' of said source, said device comprising an elon neon and mercury vapor, a similar separation gated tubular container. electrodes sealed therein takes place, the blue colored light from the mer cury vapor being present at the electrode having the smaller cathode drop and the red neon light ‘appearing at the electrode with the larger cath ode drop. In this case it is advantageous to place the source of the mercury vapor at that end 40 of the tube to which the vapor travels during the operation of the tube. 'This is accomplished in many diiferent ways, for example, an oifset chamber mounted at the desired part of the tube is particularly . e?’ective. Preferably, however, 45 the quantity of vaporizable mercury in the tube at the ends thereof, a mixture of gases therein. each of said gases having a diiierent ionising po tential said electrodes being cold electrodu, the voltage of said current source being slightly higher than the starting voltage of said device, a sensitive part of said device being grounded to transform the symmetrical alternating current into unsymmetrical alternating current in said device to cause the discharge in said device to emit diiierent colored light from different parts thereof and a luminescent material capable of is suchthat it is completely vaporized during the light emission under irradiation by said discharge mounted in light receiving relation to said dis operation thereof. charge. _ When desired, a light approximating white light can be obtained from a device similar to the de 50 vice described above when the container I is ?lled with mercury vapor and contains neon at a pres ~ 3. In combination a current source of sym metrical alternating current, a gaseous electric discharge device connected across the terminals of said source, said device comprising an elon' sure of approximately 2 mm. Inthis case the _ gated tubular container, electrodes sealed therein tube is preferably surrounded by a light di?using at the ends thereof, a mixture of argon and met jacket which mixes the red and the blue light cury vapor therein, each of said gases having a 55 emitted from different parts of the tube. In this diiferent ionizing potential said electrodes being case the container'i is preferably of U-shape or cold electrodes, the voltage of said current source is coiled helically. When desired, sodium is in being slightly higher than the starting voltage of troduced into the tubular lamp container oi the said device, a sensitive part of said device being .above embodiment and the light from the sodium grounded to transform the symmetrical alternat 60 is visible at the cathode having the smallest drop, ing current into unsymmetrical alternating cur the blue light of the mercury is visible' in the rent in said device to cause the discharge in said center portion of the tube and a red luminescent device to emit diflerent colored light from differ neon light is visible adjacent the other electrode. ent parts thereof and a luminescent material While we have shown and described and have capable of light emission under irradiation by pointed out in the annexed claims certain novel said discharge mounted in light receiving relation features of the invention, it will be understood to said discharge. that various omissions, substitutions and changes in the forms and details of the device illustrated and in its use and operation may be made by ' ‘ HANS AL'I'ER'I'HUH.. MARCEIID PIRANI.