US1659636A - Device fob amplifying voltage and cubeent - Google Patents

Description

F'. E. NULL DEVICE FOR AMPLIFYING VOLTAGE AND CURRENT Fgb; 21, V1928.

Filed Sept. 24. .1926

INVENTOR f /Vf/LL BY' M V61 ATTORNEYS Patented Feb. 21, 192.8..

UNITED STATES PATENT oEFlcE.

FLY EDISON NULL, .QFUBBANZL ILLINOIS.

DEVICE'FOB AMPLIFYINGIVOLTAGE AND CURRENT.

Application led September 24, 1.826. Serial No. 137,544.

M invention relates to a device for amp ifying voltage and current, and it consists in the combinations, constructions and arrangements herein described and claimed.

An object of my invention is to provide a device, b means of which a very high degree of distortionless voltage and Current amplification may be obtained by utilizing given voltage to deflect a retarded cathode ray for the subsequent production of Leon ard rays, by means of which the amplifica.- tion is effected.

A further object of the invention is to provide an apparatus which is composed of relativel few parts, and by means of which the amp ification is effected. v

Other objects 'and advantages will -appear in the following specification, and the novel features ofthe invention will be particularly pointed out in the appended claims.

My invention is illustrated in the accompanying drawings, forming part of this application, in which Figure 1 is a diagrammatic View of the apparatus, and

`Figures 2 and 3 are detailed views showing a perforated plate which forms a part of the apparatus. l

In carryingl out my invention I provide an envelope 1, forming achamber which is preferably `made of glass. The air isexhausted from the chamber so as to produce a good vacuum. At one end of the chamber is an electrostatic focusing mirror C. In front of this mirror is disposed a thoriated tun sten filament F, which forms the source o the cathode rays. At G1. I have shown a grid for the acceleration of a cathode beam and at G2 is a retarding grid for decreasing the velocity ofthe beam. The beam, itself, I have indicated at E. At D1 and D2 are electrostatic deflecting plates which are connected to the source V1 of the voltage to be amplified. At G3 is a neutral grid which is at the same potential as the retarding grid G2 on the opposite side of the deflecting plates. At G,i I have shown an accelerating grid, by means of which the electron beam is speeded up for the p'roduction of Leonard rays.

The envelope C', has associated with it an envelope C2 in which a secondary discharge takes place. Between these chambers, and in alignment with the central axis 0f the electron beam, is a window in which there is a perforated metal late P covered over with thin metal foil which is brazed to the surface of the plate so as to render the plate gas-tight, but to permit the producionif Leonard rays in the auxiliary cham In. the latter chamber are second discharge electrodes E1 and E2, respectively. The latter is connected to one side of a secondary discharge battery B, the opposite terminal of which is connected with one terminal where the amplified voltage V2 is to be impressed(4 The electrode E, is connected to the other terminal, a blocking condenser XC being provided in the circuit. At R I have shown a D. C. shunt.

From the foregoing description of the various parts of the device, the operation may be more clearl understood. Inorder that a large deflection of the beam may be produced by very small electrostatic deflecting fields, the cathode beam is produced in a good vacuum so as to prevent the shielding of the beam from the defiecting field by space charge. To this end the thoriated tungsten filament F is used as the electron source. The electrostatic focusing mirror C is for the urpo'se of concentrating the rays to form a eam with a cross-section of uniform current density. Since the deflection of an electron stream by an electrostatic field is inversely proportional to its velocity, great sensitivity can be obtained by passing the electron stream through a retardin field so as to greatly reduce its velocity be ore passing into the deflecting field. To this end I make use of the. grid G2 through which the beam is passed.

Since the lateral acceleration produced by the deflecting field between the plates D1 and g5 D2 is En; where X is the electric field, e is the charge, and m the'mass of the electron,

i and is 1.77X 10" electromagnetic units per gram, it is evident that a very small field will produce a great acceleration and will produce large deflections if the velocity of the electron beam is reduced so that the ac- Vpart o foil window of the ionization climber with sucient velocity to produce Leonard rays. In the osition of zero deflection of the beam,

fp the cross-section of the focused beam strikes the wall of the ionization chamber and has no useful effect, while the other part strikes the thin metal foil Window in the wall of the ionization chamber for the production of Leonard rays. Thus the variation in the magnitude of the Leonard rays produced is directly roportional to the deflection of tl1e.catho e beam.

The ionization chamber contains gas under pressure. As an example, I may use carbon dioxide gas under pressure of 3.95 mm., although the kind of gas, as pressure, and )iptential drop between the e ectrodes E, and 2 may vary Without departing from the spirit of the invention. Each negative ion produced by the Leonard rays produces several thousand more by ionization, by col' lision, in each cm. of its'path to the anode, and every new ne ative ion" produced, itself produces several tousand. electrons for each cm. of its path, so that the eifect is very greatly multiplied and a relatively large current may be produced. The discharge is still stable and directly proportional to the number of ions initially produced by the Leon-ard ra S.

- claim: v

1. In an apparatus for amplifying current or voltage, the combination of a vacuum tube, a source of cathode rays in said tube, means for directing the rays to form a beam of subf stantially uniform current density, means for rctarding the velocity of the beam, means for deliecting the beam after retardation, means for acceleratinr the deflected beam, and

means for producing Leonard rays bythe" accelerated portion of the beam.

2. In an apparatus for amplifying current y or voltage, the combination of a vacuum tube, a source of cathode rays 1n said tube,

means for directing the rays to form a beamof substantially uniform current density,

means for rctarding the velocity of the beam,

means for deiecting the beam after retardation, means for acceleratin the deiected beam, means for producing eonard rays by the accelerated ortion of the beam, a sec ond discharge c amber associated with the said irst-named tube for receiving the Leonard rays, and electrodes in said second disu charge tube.

FAY EDISON NULL.v

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