US1221034A

US1221034A - Oscillating-current generator.

Info

Publication number: US1221034A
Application number: US1722515A
Authority: US
Inventors: Lee De Forest
Original assignee: FOREST RADIO TELEPHONE AND TELEGRAPH Co DE
Current assignee: DE FOREST RADIO TELEPHONE AND TELEGRAPH Co; FOREST RADIO TELEPHONE AND TELEGRAPH Co DE
Priority date: 1915-03-26
Filing date: 1915-03-26
Publication date: 1917-04-03
Anticipated expiration: 1934-04-03

Description

L. DE FOREST. OSCILLATING CURRENT GENERATOR.

APPLICATION FILED mmzs. m5.

L%1.,@M.. Patented Apr. 3,1917.

Wit m2 0.) I nuQ-Wfoz i I A 6L (it 5 $51, 711 at use L221ld93d.

oE rEE.

LEE DE EoEEs'r, or NEW YoEK, N. Y., Assre'NoE r DE EoEEsr RADIO TELEPHONE AND TELEGRAPH coMrANY, on NEW YoEK, N. Y., A CORPORATION or DELAWARE.

OSCILLATING-GURRENT GENERATOR.

zen of the United States, and residing at New York, county of Bronx, State of New York, have made a certain new and useful Invention ,in Oscillating-Current Gienerators, of which the following is a specification.

This invention relates to oscillating current generators.

The object of the invention is to provide a high frequency oscillatingcurrent generator which is simple and efficient.

Other objects of the invention will appear more fully hereinafter.

The invention consists substantially in the construction, combination, location and relative arrangement of parts all as will be more fully hereinafter set forth, as shown in the accompanying drawings, and finally pointed out in the appended claims.

Figure 1 is a circuit diagram showing one arrangement embodying m invention.

Figs. 2 and 3 are modi 'ed constructions of oscillation generators embodying my in-.

vention. v

Fig. 4 is a sectional view taken on the line 4-4, Fig. 1, and looking in the direc-- tion of the arrows.

It is among the special purposes of my present invention to provide means for generating oscillating currents, and to so assoable resistance 8 to the electrodes 5, 6, to

heat the same and cause a vapor arc column to form in the passage 4.

In a chamber 23*, forming part of the evacuated vessel 1 and communicatin with the mercury arc passage 4, are locate ,two'cold electrodes 9 and 10, preferably arranged at different distances from the vapor arc 'column maintained in the'passagel.

4 The electrode 9 is electrically connected- Specification of Letters Patent. Patented Apr. 3, 1191].? Application filed March 26, 1915, Serial No. 17,225. I

td one terminal of a source of electroiiidtive force 11. I have found it preferable to employ a direct current generator, as shown,

but my invention is not to be limited thereto. One termmal of the current source 11 is connected'to an electrode 9, and the other terminal of said current source 11 is connectplished in any suitable convenient manner.

In the case of electrode 9 I have shown a simple arrangement wherein I employ a reservoir 13 which is provided with pipes 14;

opening upon the electrode 9 and adapted to projecting out of said evacuated vessel 1 toallow a cooling medium to circulate therethrough. My invention, however, is not to be limited or restricted in this respect.

In the usual and well known way, I as sociate an oscillating circuit with the two cold electrodes 9 and 10. This circuit consists of the usual condenser 15, and inductance 16, arranged in series with electrodes 9 and 10 and with each other. and as shown, a switch or other form of circuit make and break device 17 may also be placed in seriesin this oscillating circuit.

If desired, and as shown, a variable capacity, such as a condenser 18-, may be shunted around the inductance 16, but my invention 9'0 If desired,

in its broad'scope is not to be limited or re electrodes. The purpose of this leak path is tov conduct off the excessive charge which may cumulate on the electrode 10 and the" ,1 reduce the efficient operation of the osci'l ato aa I have discovered that if a second oscil:

lating circuit be established including therethe electrode 9 and the vaporarc main-- tained in the passage 4, the inductance and condenser 21 all in' series with each other the oscillations set up in the original oscillating

circuit

9, 16, 18, 15, 10, are increased 111 intensity provided the period of the. second oscillating circuit is made equal spect therefore, the elements20, 21, may be omittedif desired. ,When the two oscillating circuits are employed, however, the inductance elements '16, 20,- thereof, should be inductively associated.

A load or output circuit maybe associated, either inductively or conductively with one or both of the above described os- ,cillating circuits. In the arrangement shown, the load circuit is made up of a variable inductance 22 connected intermediate the radiating antenna 23 and the ground or earth 24 in the usual and well known manner for radio operation; The natural period of the load circuit should be equal to that of the-first cuit.

In Fig. 2 I show a modified form of evacuated vessel oscillator, wherein the heated electrode may be a filament instead of a i vapor arc above described. In this form of my invention the cold electrode 10 is shown in' section as a metal tube inserted inthe constricted portion of the chamber 3 -of the vessel 1, immediately above the passage 4.

Instead of employing a column of vapor, if desired, and as shown, a heavy filamentof tungsten or platinum coated with oxidof I calcium.;.or other suitable material may be employed asindicated at 25. In this in-.

- stance, heavy leading in wires. 26 are em- I h this modification of my invention is simishown in Fig. l.

ployed tosupport the heating filament 25. The circuit connections and theoperation of lar to the above described arrangement I If desired, instead of employing the merwith a suitable non-vaporizable electrode such as indicated at 2'7, Fig.3, I I Theexact operation involved in a generatorhaving the construction shown in the feed chambers. 2, 3 of Fig. 1, or the filament arrangement of Fig. 2, one of the

chambers

2, 3, may be supplied with a mercury. or'other form of electrode such as 5 or 6, while'the rawing, and as above described I have not r as'yet been able to fully and 'eompletely unoperate" as a or original oscillating cir- If the generator 11 is a direct current .source a negative current isset up across the oscillator by means of the thermions-pass ing from the hot electrode 25, 27, or the vapor arc in passage 4 as the case may be, to the cold electrode 9. A charge impressed upon the cold electrode 10 will greatly reduce the flow of thermions from the hot electrode or vapor arc to the electrode 9, or, in other words, will increase the potential drop between the cold electrode 9 and the hot electrode. Therefore, if the electrical connec- 4. tion between the electrode 10 and the electrode 9' be suddenly established by closing the switch or circuit maker 17, the positive potential of the electrode 9 and. of the positive terminal of condenser 18 will be suddenly increased. Further, any positive charge on the. electrode 10 will be rapidly carried away by action of charged thermions from the hot electrode attractedthereto, inasmuch as the capacity of the stopping condenser 15 is small. Thus a difference in potential is quickly established between denser 18. The inductance coil 16 prevents this difference of potential across the .condenser 18 from immediately equalizing and minal of condenser 18, and on the electrode I the negatively the two terminals of con 9 causes a sudden increase of positive current from source 11 which again charges one negative current again sets up across coil 16 to the other terminalof said condenser cury or other form of electrodes 6, 5 in the hot electrode to the cold electrode 9,

that is, will again still further increase the I terminal of said condenser. Thuscondenser other assoclated chamber may be provided 18 will once more begin to discharge a positive current through the, coil 16 and the en- .tire phenomena as above described, willbe 'ceeds, coil16, up to a point where the losses inthe q h circuits and in the oscillator are equal to any xderstand. I have discovered however that such an arrangement or arrangements do I generator ofh ghfrequency 1o'sc1llat1 ons' suitable fOI'TfltilQ'WQIk and, -'ture' of my invention, and various arrange- Having now described the objects and naterminal of condenser 18 positively, and a .further increasein the energy representing the'oscillations.

nearest ments for accomplishing the same, what I claim as new and useful and desire to secure by LettersPatent, is,-

I. In a system for generating oscillating current, a work circuit, and means for generating and transmitting the generated oscillations to said work circuit comprising a vapor arc and a'plurality of cold electrodes, each located at a relatively difi'erent distance from said arc and each directly conductively connected to said work circuit, and means vfor successively charging one of said cold electrodes.

2. In a system for generating oscillating current, a work circuit, and means for generating and transmitting the generated oscillations to said work circuit comprising a vapor arc and a plurality of cold electrodes, each located at a relatively diflerent distance from said arc, a'series oscillating circuit connecting said cold electrodes, and means for impressing an electromotive force upon the electrode in the space between said are and the other cold electrode.

3. In asystem for generating electrical oscillations, a work circuit, and means for generating and transmitting the generated oscillations comprising a vapor arc and a cold anode, a source of electromotive force in series relation between said vapor arc and anode, a second anode, and a series oscillating circuit connecting said anodes.

4. An oscillator for generating high frequency oscillations comprising an evacuated vessel and a vapor arc. and two cold electrodes contained therein, av current source connected between one of said cold electrodes and the vapor arc, and a series oscil lating circuit connected between said cold electrodes to set up an alternating current therebetween, a work circuit and means to transmit the generated osc'llations to said circuit.

5. An oscillating system consisting of a vapor arc and a cold anode, a source of electromotive force in series circuit relation between said vapor arc and anode, a secondanode, and a series oscillating circuit connecting said anodes, a work circuit, and means to transmit the generated oscillations to said .WOI'k circuit.

6. An oscillating system consisting of a heated cathode and a cold anode, a source of electromotive force in series circuit relation between said cathode and anode, a second anode, and a series oscillating circuit connecting said anodes, and a second oscillating circuit associated with said first mentioned oscillating circuit, an antenna system, and means for transmitting the generated oscillations to said antenna system.

In testimony whereof I have hereunto set.

my hand witnesses, 1915.

in the presence of the subscribing on this 24th day of March A. D.,

LEE D'E FonEs'r.