Патент USA US2118981код для вставки
May 31, 1938. H. M. MUNCHERYAN 2,118,981 ELECTRIC DISCHARGE TUBE Filed July 3, 1936 INVENTOR. Hrand BY j?urzclzer an ATTORNEY ‘ Patented May 31, 1938 Fro 2,118,981 ELECTRIC DISCHARGE TUBE Hrand M. Muncheryan, Los Angeles, Calif. Application July 3, 1936, Serial No. 883191,‘; 9 Claims. (01. 176-122) My invention relates to electric discharge tubes adapted for illumination, recti?cation, and volt wardly of the envelope for exhausting the en velope of air and re?lling it with the required age regulation which can be mounted and oper gases. This tube has an opening 28 leading to? the interior of the envelope, and its free end is ated in an ordinary incandescent lamp socket. It is a purpose of my invention to provide a tube of this character which is capable of being started and operated at voltages" corresponding to the low operating voltages of incandescent lamps. 10 A further purpose of my invention is the pro vision of an electric discharge tube which, with no increase in current consumption and at low ‘operating temperatures, produces illumination of considerably greater intensity than is pos 15 sible with incandescent lamps, and of the same radiant character as incandescent lamps. It is also a purpose of my invention to provide an electric discharge tube embodying electrodes having electron-emitting chemicals which, dur 20 ing operation of the tube, partially decompose and produce a gaseous medium having that characteristic of producing radiant light of great intensity and daylight in color, when ionized. I will describe only one form of electric dis 25 charge tube embodying my invention, and will then point out the novel features thereof in claims. In the accompanying drawing: Fig. 1 is a view showing in longitudinal section‘ 80 one form of electric discharge tube embodying my invention. Fig. 2 is a similar view taken at right angles to Fig. 1. Fig. 3 is a transverse sectional view taken on the 35 line 3—3 of Fig. 1. ’ Fig. 4 is a view showing in detail perspective the electro-conducting elements of the tube. Referring now to the drawing, the tube in no cludes a transparent envelope l5 which is gen erally similar to an incandescent lamp bulb. The envelope is provided with a central glass stem l6 ' through which pass leads I‘! and Ill. The‘ en velope is mounted in a standard base which in-~ cludes a threaded metal cup l9 ?lled with a body 45 of insulation 20, the lead I‘! passing through the insulation and electrically connected to the .cup in any convenient manner, as at 2|. The cup has an open bottom closed by an insulating cap 22 and secured to this capby a tubular rivet 23 50 is a metal contact disk 24. A lead 25 is secured to and extends inwardly from the disk for con nection to one terminal of a choke coil 26 sit uated within the body 20. The other terminal of the coil is connected to the lead l8. ' 55 From the glass stem I6 a tube 21 passes out sealed o? after the pumping process. Integral 5 with the inner end of the stem I6 is a bowl shaped glass support 29 enclosing two electrodes 30 preferably, although not necessarily, of sub stantially semi-circular form with their ?at sides confronting. These electrodes are electrically 10 separated one from the other by a septum 3| of insulating material which is preferably transpar ent, such as mica. The septum is of a width slightly less than the internal diameter of the envelope, and of such a 15 length as to terminate short of the rounded end of the envelope. It is supported in ?xed posi tion by a pair of electro-conducting elements 32 and 33, in the form of metal strips arranged centrally at opposite sides of the septum with one of’ their ends extending between the elec trodes 30 and spot-welded thereto so as to be electrically connected therewith. The other ends of the strips are bent in opposite directions around the free end of the septum and spaced from each other as shown. The element strips are provided with integral and lateral extensions 32“ and 33“, respectively, bent and extended through slots 34 in the sep tum 3|, so that the free ends of the extensions of one strip are disposed at the opposite side of the septum from that of the respective strip, and in spaced relation to the other strip. Also, the extensions of one strip are staggered with rela tion to those of the other strip to provide inter vening electric discharge gaps. It will be un derstood that the gap between the terminals of the strips which are bent around the end of the septum also constitute an electrical discharge gap 40 Thus it is now apparent that the two elec tro-conducting elements 32 and 33 are electri cally connected to the respective electrodes 30 and electrically disconnected from each other, with discharge gaps along the length thereof and at the free terminals thereof. Further, the association of the strips and extensions with the electrodes and septum, is such that the septum is securely held in ?xed position within the enve lope. , At the center of each electrode 30 is a recep tacle 35 perforated or porous and of inverted cup form. This receptacle is secured in the electrode by screw-threading, indicated at 36, or in any other suitable manner, and it contains a compo 50 2 2,118,981 sition 31 constituting a source of carbon dioxide, as will be presently described. To the electrodes 30 are connected the leads I‘! and I8, respectively, so that the receptacles and the compositions therein constitute parts of the electrodes. In practice, the envelope is adapted to be ?lled with a mixture of neon, argon and carbon dioxide, or any of the other inert rare gases in combina tion with carbon dioxide. This mixture is con 10 tained in the envelope at a pressure of between 7 and 16 millimeters of mercury pressure, with a preferred pressure of 9 millimeters. Preferably, the gases are employed in the ratio of 60% neon, 10% argon, and 30% carbon dioxide. The electrodes 30 are made of any suitable re oxide, either of which are good- electron-emitting materials. ' In operation of the tube, a potential applied to the electrodes momentarily establishes a starting path for the discharge having a rising voltage characteristic. This starting path includes the coated elements 32 and 33 and their extensions, the extensions and the free ends of the elements . functioning as auxiliary electrodes, With alter nating current applied to the tube, ?rst the ex tensions of one element and then the other oper ate as cathodes and anodes. soon as a potential is applied a appears simultaneously at each element extensions, and as the Accordingly, as close ?tting glow gap between the current ?ow in 15 fractory metal such as copper, iron, or nickel, creases the glow spreads along the whole length preferably copper; The copper is coated with any of the strips until eventually the current is trans suitable electron-emitting substance such as a . ferred to the gaseous path between the electrodes, mixture of thorium and zirconium compounds. and the function of the strips and extensions I have found that 75% to 90% thorium oxide and ceases almost entirely. With transfer of current 10% to 25% zirconium oxide gives very satis to the gaseous medium a running path from one factory results. . electrode around the septum to the other elec The receptacle 35 may be made of perforated trode is established having a falling voltage char metal or carbon. In either event the composition acteristic. Once this running path is completed 31 constituting the source of carbon dioxide pref the positive luminous column is completed within erably comprises barium carbide 20%, to 30%, magnesium carbonate 50% to 60%, and lantha num carbonate 20% to 30%, all mixed with a binder of equal parts of sodium silicate and zir— conium hydride. _ By virtue of the many auxiliaryelectrodes thus provided, and the large volume of electrons emitted from the elements 32 and 33 and their coatings 39, starting and further ionization of ' carbonates are desirable because during the operation of the tube the salt dissociates into the element radical and carbonate radical. The carbonate radical still further dissociates into car bon dioxide and the remaining oxygen combining with the element radical forms an oxide of that element. the envelope. As the amount of carbon dioxide gas in ' _ the inert gaseous ?lling in the envelope is rapidly effected to reduce the starting period and the period of prolongation of the luminous column. Carbon dioxide has been selected as constitut ing a part of the gaseous ?lling because it pos sesses that property when ionized of producing, for all practical purposes, white light or day the envelope decreases by use, the carbonate salts light, and, hence, a light which is radiant and of thereby compensate, for this decrease by produc great intensity. However, carbon dioxide is ioniz 40 ing carbon dioxide gas. As this cycle goes on,. able only at relatively high voltages, and hence, carbon dioxide is constantly fed into the path of if used alone in a tube, the tube could not be oper the discharge where it is utilized together with ated on 110 volt current in place of an incan other gaseous matters in the production of light descent lamp. Therefore, to effect ionization of in the envelope. ' 45 Barium carbide further decomposes into barium and carbide radical which reacts with the oxygen given off by carbonate radicals of magnesium and lanthanum, and produces more carbon dioxide, which is essentially utilized in the production of a 50 luminous column of light between the electrodes. Zirconium hydride acts as dissociator of barium carbide into barium and carbon, and also acts as a catalyst in the formation of carbon dioxide of this free carbon and the excess oxygen liberated by the carbonate radicals. carbon dioxide without increasing the potential applied, it is mixed with one or more inert gases which are ionizable at relatively low voltages. Thus, through initial ionization of the inert gases ionization of carbon dioxide is e?ected without increasing the voltage beyond that neces sary to ionize the inert gases. ' My reason for selecting carbon dioxide is not because it is the only chemical that possesses that property of producing radiant light of great luminosity when ionized, but because it is the cheapest of known chemicals possessing this 55 Further, zirconium has the property of absorb- a property. Other related chemicals and anthra ing a large quantity of carbon dioxide gas during quinone and its related group may be employed. By reason of the auxiliary electrodes as de O processing of the tube, as well as when the tube is scribed above and the choke coil 26,‘sputtering inactive. In the latter case, the absorption prop erty of zirconium is utilized to reduce the number due to abnormal current density or ?uctuations of carbon dioxide molecules in the envelope and at the electrodes during any interval of current thereby facilitate ionization of the inert gases when restarting the tube, thus rendering the car bon dioxide as emitted from the composition more easily ionizable. The electro-conducting elements 32 and 33 and their extensions are made of any metal having that property ‘of emitting electrons when a poten 70 tial is applied thereto while coated with an alkali earth metal. Cadmium, antimony and aluminum are metals possessing this electron-emitting prop erty, and preferably I employ aluminum. In the drawing, 39 indicates the coating of an alkali 76 earth metal such as magnesium oxide or barium alternation, is eliminated. I claim: 1. An electric discharge tube, comprising; an ' envelope containing a gaseous ?lling; a pair of electrodes mounted side by side within the en velope; a septum of insulating material extend ing between the electrodes; and electro-conduct ing elements secured to the electrodes and em bracing the septum for holding the latter in 70 ?xed position within the envelope. 2. An electric discharge tube, comprising; an envelope containing a gaseous ?lling; a pair of electrodes mounted side by side within the en velope; a septum of insulating material extending 75 2,118,981 3 element having parts extending through the sep 8. An electric discharge tube, comprising; an envelope containing an inert gas; a pair of elec-; trodes side by side within the envelope adjacent one end thereof; each comprising a cupped body tum and'spaced from the parts of the other ele ment to form intervening gaps. emitti'ng substance, and a porous receptacle ?xed between the electrodes; and at least a pair of electro-conducting elements on opposite sides of the septum secured to the electrodes and each 3. An electrode for discharge tubes, compris ing; a body of refractory metal coated with an electron-emitting substance; a porous receptacle 10V of electro-conducting material; and a composi tion in said receptacle comprising barium carbide, magnesium carbonate and lanthanum carbonate. 4. An electrode for discharge tubes, compris ing; a body of refractory metal coated with an electron-emitting substance; a porous receptacle of electro-conducting material; a composition in said receptacle comprising barium carbide, mag nesium carbonate and lanthanum carbonate; and a binder comprising zirconium hydride and an equal amount of sodium silicate. 5. An electrode for discharge tubes, compris ing; a body of refractory metal coated with an electron-emitting substance; a porous receptacle of electro-conducting material; and a composi tion in said receptacle comprising 20% to 30% barium carbide, 50% to 60% magnesium carbon ate, and 20% to 30% lanthanum carbonate. 6. In an electric discharge tube, a pair of elec trodes; a septum of insulating material between 30 the electrodes; elements on opposite sides of the septum electrically connected to the electrodes and electrically disconnected from each other, each of said elements being constructed of alu minum coated with magnesium oxide. 7. In an electric discharge tube; a septum of insulating material having slots therein; and a pair of electro-conducting elements at opposite sides of the septum having lateral extensions, the extensions of one element being extended through certain of the slots and the extensions of the other element being extended through the remaining slots and spaced from the extensions of the ?rst element to provide intervening gaps. of a refractory metal coated with an electron centrally within the body and containing carbon ates for producing carbon dioxide gas in the en velope; a slotted septum of insulating material having one end between the electrode bodies and the other end spaced from the other end of the envelope; a pair of electro-conducting strips at opposite sides of the septum having one of their ends secured to the electrode bodies and the other of their ends extended around the free end of the septum; angular extensions on said strips pro jecting through the slots of the septum and co acting with each other and the strips to secure the septum in fixed position within the tube and to form gaps between the strips and extensions; and a coating of electro-emitting material on the strips and extensions. 9. An electric discharge tube, comprising; an envelope containing an inert gas; a pair of elec trodes side by side within the envelope adjacent one end thereof; each comprising a cupped body 10 15 20 25 of a refractory metal coated with an electron emitting substance, and a porous receptacle ?xed centrally within the body and containing car bonates for producing carbon dioxide gas in the envelope; a slotted septum of insulating mate rial having one end between the electrode bodies and the other end spaced from the other end of the envelope; a pair of electro-conducting strips at opposite sides of the septum having one of 35 their ends secured to the electrode bodies and the other of their ends extended around the free end of the septum; and extensions on said strips pro jecting through the slots of the septum and co acting with each other and the strips to secure 40 the septum in ?xed position within the tube and to form gaps between the strips and extensions. HRAND M. MUNCHERYAN.