US1984429A - Gaseous electric discharge lamp device - Google Patents

Description

Dec. 18, 1934. P|RAN| ET AL 1,984,429

GASEOUS ELECTRIC DISCHARGE LAMP DEVICE Filed July 21, 1933 INVENTORS Patented Dec. 18, 1934 I UNITED STATES PATENT OFFICE GASEOUS ELECTRIC DISCHARGE LAMP DEVICE Marcello Pirani, Berlin-Wilmersdorf, and Martin Reger, Berlin, Germany, assignors to General Electric Company, a corporation of New York Application July 21, 1933, Serial No. 681,592 In Germany August 1-9, 1932 5 Claims. (01. 176-122) The present invention relates to gaseous elecused in the device. Since high current densities tric discharge lamp devices generally and more can be used in this type of gaseous electric disparticularly the invention relates to improvecharge lamp device it is possible to vaporize in ments in concentrated light sources useful in conthe lamp metals having a vaporization tempera- 5 nection with television, sound reproduction, specture of over 500 C., such as alkali earth metals 5 trometry and similar arts. I which vaporize at a temperature of between 600- The object of the present invention is to pro- 800 C. as well as metals having a lower vaporizvide a gaseous electric discharge lamp device ing temperature, such as mercury. The vaporwhich is a concentrated, brilliant, uniform, high ized metal is then present in the gaseous electric intensity point light source. Another object of discharge path and the spectrum of the light 10 the invention is to provide such a lamp device emi ted by t e a p s strong in t y c a startable and operable on either alternating or aeteristie 0f the metal p When Such metal direct current. A further object of the invention V p are d in the l p We prefer to use a is to provide a lamp device of the above type Starting gas,s11eh as argon, at a pressure pp 15 wherein high current densities can be used. A ciably a r a tha of t -m al vapor p sfurther object of the inventi n i t provide sure in order to reduce the rate of difiusion of gaseous electric discharge lamp device of the the metal v p r through the Op n n in he housabove type wherein the vapor of difficultly vapor-V ing to a minimum. Bafiles are also used for this izable metals, such as sodium, constitutes the gasp p w d s d- The m l housing ateous filling or is a component of the gaseous filltains at the highest a dull red temperature and 20 ing. A still further object of the invention is to does not emit light of an intehsitytwhieh wou d i provide su h a lamp d i of simple Structure mix with the light emitted by the gaseous elecand the manufacturing cost of which is reduced tric discharge in he v Th housing is pto a minimum. Further objects d advantages arated from the walls of the glass container of attachi t th d i and t use Operation the device so that said glass walls of the container 25 will be apparent to those skilled in the art from do t attain a dan r us t mp atu e du the following particular description. the Operation of the device- The invention attains its objects by providing In the drawing a c mpanyin and formin part a metal housing in the glass container of a gasof this Specification W b d ts of the in- 0 eous electric discharge lamp device completely vention are shown in which enclosing th gaseous 1 tri discharge. The Fig. 1 is a side elevational view of one emboditerior of said housing is divided by a wall having ment of the invention. a communicating passage therein. A th iem Fig. 2 is a similar view of the same embodiment electrode is mounted on each side of said wall m the POSitiOn shown in 1, and

5 in said housing out of line with the passage in Fig. 3 is'a side elevational view of another emsaid wall. The light emitted by the gaseous elecbodiment of the Inventiont discharge passes through an opening in said Like numbers denote like parts in all the figures. housing co-axial with the communicating pas- Referring to Figs. 1 and 2 of the drawing the sage in said wall, and the gaseous electric disnew and W lamp Flevlce compnses a bulb like charge in the device is viewed end on through said glass contamer 1 haYmg m Current least 40 opening A concentrated, high intensity light 4 and 5 are sealed into the pinch part 3 of said spot of great surface brightness and uniformity stem 2 n elgctrodes 10 and 11 mounted on is thus made available for use in the arts generthe ends of sald.leads 4 and said leads and ally. When the wall dividing the metal housing 5 *P m tubes 17 and i i is of metal it will be understood of course that of insulating material, such as magnesium oxide,

the potential applied to the device is greater than prevent an electnc dlscharge between said leads 4 and 5 and to insulate said leads 4 and g j ?25 2 53; gggi g ggggg gfggg i figg z 5 from the walls of a metal housing 6 mounted take place between the electrodes and the walls m Sam contamer said housmg 6 is of tangular shape and is made of sheet metal. 0f the hOusmg- The gaseous electl'lc dlschm'ge Supports 7 and 8 fused into the pinch part 3 then follows a Pa h through the communicating of said stem 2 are provided for said housing p a e i the partition- A p device having 6. The space in said housing 6 is divided into the above structure is easily and in Ypensively two parts by a diagonal wall 9 of sheet metal 5 manufactured and high current densities can be and one of said electrodes 10 and 11 is located 10 12 and which is indicated at 13.

in each of said parts. Said electrodes 10 and 11 are electron emitting when heated and comprise a metal filament, such as a tungsten filament, coated with an electron emitting material, such 5\ as barium oxide. A cylindrical tube 12 of small internal diameter pierces said partition 9 to form a communicating passage between the two parts of said housing 6. The top wall of said housing 6 has an opening therein co-axial with said tube Said thermionic electrodes 10 and 11, which operate at an incandescent temperature, are out of line with said tube 12 and are not visible through the opening indicated at 13. The discharge path between 5 said electrodes 10 and 11 goes through said tube 12 when the potential applied across the electrodes 10 and 11 is greater than the combined anode and cathode potential drop of a discharge between said electrodes 10 and 11 and the walls of said housing 6 and the gaseous electric discharge is concentrated in said tube 12. The part of the gaseous electric discharge located in said tube 12 is visible end-on through the opening "13 and is a concentrated, brilliant, uniform, high intensity spot, or point source of light. The

gaseous electric discharge is completely surrounded by the housing 6.

Said container 1 is filled with a rare gas, such as argon or neon, at a'pressure of approximately 1-10 mm. When desired, a vaporizable material,

particularly important where an alkali metal vapor, such as sodium vapor, is used as a component of the gaseous filling toprotect the glass container from the chemical effects of such vapor. Said container 1 is made of a glass resistant to 5 the chemical efiects of the alkali metal vapor,

when desired. The gaseous electric discharge between said electrodes 10 and 11 first takes place in the rare gas. The gaseous electric discharge raises the temperature of said housing 6 and the vaporizable metal contained in said housing 6 to the vaporization temperature of the metal and the metal is then present in vaporous form in the discharge path during the operation of the device. The spectrum of the light emitted by the device is rich in rays characteristic of the metal vapor dur-' ing the operation of the lamp device. The housing 6 is separated an appreciable distance from the walls of container 1 which protects said walls from the heat of the gaseous electric discharge during the operation of the lamp. High current densities necessary to generate enough heat to.

70 bodiment the partition 9 is vertical and the electrodes 10 and 11 are in the same horizontal plane. The tube 12 is located above said electrodes 10 and 11 and-the longitudinal axis thereof is parallel to the plane of said electrodes. The ends of 7 said tube 12 extend beyond said electrodes 10 and 11. A tube 14, which is co-axial with said tube 12, protrudes from one of the side walls of said housing 6 and acts as a baffle for the particles of vaporized material in said housing to retard the rate of diffusion. of the metal vapor from the housing 6 to containerl. The glass walls of said container 1 are thus kept free from undesired light absorbing deposits of condensed material and said walls are protected from the chemical efiects of the vapor filling. The gaseous electric discharge is visible through the opening in said tube 14 and is a concentrated, bright, intense, uniform spot of light. A ring-shaped electrode 15 mounted on current lead 16 sealed into the pinch part 3 of said stem is adjacent the external end of said tube 14 and is concentric with the longitudinal axis of said tube 14. Said electrode 5 is connected as an auxiliary starting electrode when the electric discharge device is operated on alternating current and as an anode when the device is operated on direct current, when desired.

While we have shown and described and have pointed out in the annexed claims certain novel features of the invention, it will be understood 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 those skilled in the art without departing from the broad spirit and scope of the invention, for example, any of the well known types of thermionic electrode, such as the oxide coated, metal shell-type Hull electrode, or the mixed, sintered metal and oxide type Pirani electrode, can be used in place of the electrodes 10 and llashown and described.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. An electric discharge device comprising a container, electrodes sealed therein, a gaseous atmosphere therein, a housing in said container, a vaporizable material in said housing, said housing being divided into chambers by a partition having a communicating passage of appreciable length therein, one of said electrodes being mounted in each of said chambers, and one of the walls of said housing being perforated in line with said communicating passage, the end of said passage being at an appreciable distance from the opening in said housing.

2. An electric discharge device comprising a container, electrodes sealed therein, a gaseous atmosphere therein, a housing in said container, 9. vaporizable material in said housing, said housing being divided into chambers by a partition having acommunicating passage of appreciable length therein, one of said electrodes being mounted in each of said chambers, out of line with said passage and one of the walls of said housing being perforated in line with said communicating passage, the end of said passage being at appreciable distance from the opening in said housing.

3. An electric discharge device comprising a container, electrodes sealed therein, a gaseous atmosphere therein, a housing in said container, a vaporizable material in said housing, said housing being divided into chambers by a partition having a communicating passage of appreciable length therein, one of said electrodes being mounted in each of said chambers, a tube in the wall of said housing co-axial with said communicating passage and spaced an appreciable distance from the end of said passage.

4. An electric discharge device comprising a women container, electrodes sealed therein, a gaseous atmosphere therein, a housing in said container, a vaporizable material in said housing, said housing being divided into chambers by a partition having a communicating passage of appreciable length therein, one of said electrodes being mounted in each of said chambers, a tube in the wall of said housing co-axial with said communicating passage and spaced an appreciable distance from the end of said passage, another of said electrodes being mounted outside of said housing and adjacent the external end of said tube.

5. An electric discharge device comprising a container, electrodes sealed therein, a gaseous atmosphere therein, a housing in said container, said housing being divided into chambers by a. partition having a communicating passage of appreciable length therein, one of said electrodes being mounted in each of said chambers, and one of the walls of said housing being perforated in line with said communicating passage, the end of said passage being at an appreciable distance from the opening in said housing.

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