US2056648A

US2056648A - Gaseous electric discharge device

Info

Publication number: US2056648A
Application number: US663792A
Authority: US
Inventors: Eduard G Dorgelo; Bol Cornelis
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1931-12-23
Filing date: 1933-03-31
Publication date: 1936-10-06
Anticipated expiration: 1953-10-06
Also published as: DE652752C; FR741891A; NL45860C; GB457740A; GB392796A; FR47656E; BE390343A; GB401240A

Description

Oct 6, 1936s Eye. DORGELO ET AL 9 5 GASEOUS ELECTRIC DISCHARGE DEVICE Filed March 51, 1933 g j i W ATTORNEY Patented Oct. 6, 1936 UNITED STATES PATENT OFFICE 2,056,648 GASEOUS ELECTRIC nrscmmca mavrcn' Application March 31, 1933, Serial No. 663,792

In the Netherlands July 27, 1932 3 Claims.

The present invention relates to gaseous electric discharge devices generally and more particularly the invention relates to improvements in such devices the gaseous atmosphere of which comprises a metalvapor.

In many cases it is desirable to maintain the container of an electric discharge device having a gaseous atmosphere comprising a metal vapor at a high temperature in order that the metal vapor will be at a correspondingly high pressure during the operation of the device. The most practical method of accomplishing this result is by reducing the radiation of heat from the container to a minimum and the container of prior devices using this method have had a double walled structure. have proven successful in operation they are very expensive and diflicult to manufacture and do not lend themselves readily to manufacture by an automatic machinery.

The object of the present invention is to provide a lamp unit of simple structure in which the container of the gaseous electric discharge device is at a high temperature during the operation of the lamp unit. Another object of the invention is to provide a lamp unit of the above type which leads itself readily to manufacture by automatic machinery. A further object of the invention is to provide a lamp unit the elements of which are quickly and easily assembled. Fur- 3o ther objects and advantages attaching to the de vice and to its use and operation will be apparent to those skilled in the art from the following particular description.

In accordance with these objects the new and novel lamp unit comprises a gaseous electric discharge device having a gaseous atmosphere comprising a metal vapor and a double-walled light transmitting envelope therefor separate from said 0 container. The space between the container of the device and said double walled envelope is closed oii by a ring of heat insulation material, for example. Said heat insulation ring comprises a resilient core, such as a metal spring, covered 45 with a heat insulation material, such as asbestos. Said insulation ring fits into circular recesses in the container of the lamp device and presses against one of the walls of said double walled envelope. A lamp unit having the above structure lends itself readily to manufacture by automatic machinery as the gaseous electric discharge device and the envelope therefor are made separately on standard machines well known in the art. The container, the envelope and the heat insulating ring are easily and quickly assembled Although such prior devicestainer 21 has two electron emitting cathodes 20 into a lamp unit. Further if one of the separate elements of the lamp unit breaks during the operation of the unit it is necessary to replace only that element rather than the whole structure which makes the lamp unit a very practical de- 5 vice.

In the drawirm accompanying and forming part of this specification several embodiments of the invention are illustrated in which Fig. 1 is an elevational, schematic view of one embodiment of the invention,

Fig. 2 is a top, partly sectional view of a heat insulating ring useful in the embodiment of the invention illustrated in Fig. l and Fig. 3 is an elevational, schematicview of another embodiment of the invention.

Like numbers denote like. parts in all the figures.

Referring to Fig. l of the drawing the new and novel lamp unit comprises a gaseous electric discharge device having an elongated container 21. Said container 21 is filled with a gaseous atmosphere, such as sodium vapor, or a mixture comprising a rare gas, such as neon, argon, and a metal vapor, such as sodium vapor. Said conand 2| and two

anodes

22 and 23 sealed into the 5 stem 28 thereof. Said

anodes

22 and 23 are metal cylinders connected to and surrounding said cathodes 20 and 2|. Said cathodes 20 and 2| consist of a metal filament, such as a tungsten filament, coated with an electron emitting material, such as barium oxide. During the operation of the gaseous electric discharge lamp device on alternating current the gaseous electric discharge is supported by said

cathode

20 and 35 said anode 23 and by said cathode 2| and said anode 22 alternately.

A disc 29 of heat insulating material, such as a mica disc, rests on said stem 28 and presses against the lower part of the circular indentation 30 in the walls of said container 21. The upper part of said container 21 is filled with a gaseous mixture comprising a rare gas, such as neon, and a condensible metal vapor, such as sodium vapor. The disc 29 substantially or completely, as desired, seals of! the lower, stem part of said container 21 from the upper part of said container 21. The condensible metal vapor is thus prevented from entering the lower part of said container 21 which is the coolest part of said container during the operation of the gaseous electric discharge device. The un desired condensation of the condensible metal vapor in the lower part of said container 21 is thus avoided during the operation of'the device. 5

- spring 3| covered with a heat insulating material 32, such as asbestos, is located in the circular indentation 39 of said container 21 and presses against the inner wall of said envelope 9 to close off the space between the inner wall of said envelope 9 and said container 21 and to separate said lamp parts. Having this structure the container 21, the envelope 9 and the ring ll, 32 are quickly and easily assembled into a lamp unit and said envelope 9 is easily removable from said container 21. By virtue of this structure of the lamp unit the heat generated by the gaseous electric discharge between the electrodes of the device is retained within the space between said container 21 and the envelope 9 so that said container 21 is at a high temperature during the operation of the lamp unit to maintain the vapor in the electric discharge device at a correspondingly high pressure during the operation of said lamp unit. The metal vapor thus participates in conducting the electric discharge between said

electrodes

22 and 23 and the spectrum of the light emitted by the lamp unit is rich in the light rays characteristic of the metal vapor.

The embodiment of the invention illustrated in Fig. 3 is similar to that illustrated in Fig. 1 except that in this embodiment the gaseous electric discharge lamp device is provided with a cylindrical base 33. The outer diameter of said base 33 closely approaches the inner diameter of the inner wall of said envelope 9 to prevent the entrance of the colder outside air into the space between the inner wall of said envelope 9 and said container 21. A shoulder 4| is provided on said base 33 to assist in supporting said envelope 9.

Circular electrodes 35 and 36 having electrode leads 31 and 39 attachedthereto respectively are sealed into the space between the inner and outer wall of said envelope 9. A gaseous atmosphere which emits light of the same or of a difierent color as that emitted by the gas in said container" 21 is present in said envelope 9. Where the gaseous atmosphere in said container 21 com prises sodium, for example, said envelope 9 is filled with neon at a pressure of approximately 1-10 mm. During the operation of the above described lamp unit the light emitted by the gaseous electric discharge between said electrodes 35 and 39 complements the light emitted by the gaseous electric discharge lamp device having the container 21. In other respects the operation of the embodiment of the invention illustrated in Fig. 3 is the same as that of the embodiment illustrated in Fig. 1.

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, other gaseous atmospheres such as a mixture of argon and mercury vapor, or mercury vapor alone is present in the space between the inner and outer walls of said envelope 9, where desired.

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

1. A lamp unit comprising in combination, a gaseous electric discharge lamp device having a container, a double walled envelope substantially surrounding said container, a circular recess in said container and a resilient, heat insulating ring fitted into said recess and pressing against the inner wall of said envelope.

2. A lamp unit comprising in combination, a gaseous electric discharge lamp device having a container, a double walled envelope substantially surrounding said container and a resilient, heat insulating ring interposed between said container and the inner wall of said envelope.

3. A lamp unit comprising in combination, a gaseous electric discharge lamp device having a container, a gaseous atmosphere therein and a vaporizable metal therein, said container having a stem part and a septum closing oif said stem part from the part of said container containing said vaporizable metal, a double walled envelope substantially surrounding said container and a gasket of flexible, heat insulating material fitting around said container and against the inner surface of said envelope, said gasket being substantially in line with said septum.

EDUARD G. DORGELO. CORNELIS BOL.