US2755412A

US2755412A - Electron valve

Info

Publication number: US2755412A
Application number: US283395A
Authority: US
Inventors: Sternbeck Olaf
Original assignee: Telefonaktiebolaget LM Ericsson AB
Current assignee: Telefonaktiebolaget LM Ericsson AB
Priority date: 1951-07-05
Filing date: 1952-04-21
Publication date: 1956-07-17
Anticipated expiration: 1973-07-17
Also published as: GB729468A; FR1063263A; NL275650A; DE1101631B

Description

July 17, 1 o. STERNBECK 2,755,412

ELECTRON VALVE Filed April 21 1952 5 Sheets-Sheet l INVENTOR QLJZSF STERNBFCK BY Q QM BT TORN EYES July 17, 1956 o. STERNBECK 2,755,412

ELECTRON VALVE Filed April 21 1952 5 Sheets-Sheet 2 13 FIG. 3

INVENTOR OLA? STERNBECK BYOQZ/QM ATTORPBQYS July 17, 1956 o. STERNBECK 2,755,412

ELECTRCN VALVE Filed April 21 1952 5 Sheets-Sheet 3 FIG. 6A 79 fir 23 IN EN R L AF TERN l K Q/r 2 m:

BTT RNRYS July 17, 1956 Filed April 21 1952 0. STERNBECK ELECTRON VALVE 5 Sheets-Sheet 4 n aw TOR LA) TERNBE K a /QM July 17, 1956 o. STERNBECK 2,755,412

ELECTRON VALVE Filed April 21 1952 5 Sheets-Sheet 5 FIG. 9A

INW NT R LA? TRN B Q/QQ ET T RNY United States Patent" 0 The present invention relates to an electron valve with revolving electron beam to be used especially as counting valve, that is to count electric impulses. v

It is earlier know-fits arrange in amagn'etic field high va'c'iinm electron valves provided with a cathode located a centrally within the valve and a number of electrodes i. e. anodes, positive in relation to the cathode and surrounding said cathode. The cathode may thereby be cylindric and the anodes oblong and chiefly parallel with the cathode. The said magnetic field is chiefly constant and its lines of force are nearly parallel with the cathode cylinder. In such a valve negative internal resistances can be obtained for one or more of the anodes if its potential is lowered below the potential of the other anodes. F0'r a fuller explanation of these operational features reference should b'e had to Backmark Patent No. 2,591,997, granted April 8, 1952, for Electron Tube Device.

In a proposed electron valve of said kind the electrodes su'r'ronnditfg the cathode are of two difierent types, on

one hand receiving electrodes arranged to receive the electron beam emitted by the cathode, and on the other hand control electrodes; for directing the electron beam to one, arbitrarily, of the receiving electrodes. The receiving electrodes andt'he control electrodes surrounding the cylindric cathode are shapedasrails running parallel with thecathode the receiving electrodes and the control electrodes thei eby" alternating with each other the last mentioned electrodes havinga wider extent radially towards the cathode and having the part racing h'e cathode located closer to said cathode than the receiving electrodes. A box comprising one or more receiving electrodes is thereby formed between adjacent control elect hes-r 'ev it at' ai l 'te' a ve b s a Such =i'. .s z t q l pti fi l l $ii dua m bf he valve can beconsiderably simplified if recei ng electrodes are connected witheach 0t er electrically si o" that each of them hasthe sa rie positive potential with regard to the cathode. The control electrodes are used for controlling the electron beam by supplying one of them a lower voltage than the others, whereby the beam 5 is guidedinto a boit adjacent to said control electrode. The electron beam can he made to revolve within the valve, i. e. automatically to perform a stepping movement from be)? to boat, by successively supplying tlie control electrodes following each otherwith such a low voltage. This can be done in several different manners, for ex: ample by feeding a multiphase voltage to the control electrodes", which i's knownearlier. I

The said connection of the receiving electrodes can be arranged Within the valve itself and the simplest manner is then to replace the r'eceiv'ing electrodes By a screen or metal, concentric with the cathode and located behind the control electrodes, seen from the cathode. The stepping movement of the electron beam will naturally not be aflected thereby, but can be effected in the usual way. The constn'lction of the valve will however be much 2,755,412 Patented July 17, 1956 since anuniher of through its glass emr'l'dise can lJ Ofi'li di Thee 'on vet-Ive according to'the invention is chiefly chara'cteriz'edin that it comprises acylindric cathode located centrally Within the valve envelope, a number of control electrodes coaxiallysurrounding said cathode, and a cylindric receiving electrode coaiiially encircling the cathode and the con'ttol electrodes Each part the receivingl elec trode located in' a b'o'x between adjacent control lectfodes is provided with a hole thtong h which aptirtionof theelectron bearir emitted from the can penetrate, when it is steered into said boir, and light ac'orresponding pat-tot on the outside of the receivin'g' eliectrode, which screen is coated with luiiii s n ma a.

The invention will be describedmore' in detail with reference to the/accompanying drawing. 2 v N Fig. l on the drawing shows sch'elnaticallya with negative internal resistancein the casewhere all the anodes have the same positive potential with relation to Fig. 2 shows the same valve with a 10' v 11 one of the anodes. Fig. 3 shows a sim e embodiment of a valve according to the invention. F g 4 shows avalve rwhere the position of the control electrodes in the valve has been changed. Fig; 5 shows a valve further modified control electrodes. Fig. 6A shows a horizontal and Fig; 6" a vertical section of a; valve according to the invention provided with at nescent screen. Fig. 7 shows a horizontal section elnd Fig. 7A a side-view of a. valve with another kind of coat ing on the; lnminescent screen'; Fig. and Fig. 8Aand Figs. 9 and 9A separately show a si iew and a N of electrode systeinin other embodiments" of a valve according to the invention. I l

, In Fig. ion the drawing is shown a previously known electron valve of the magnetron type withnegative lllf teriial re istance, the athode not which is sump-tinned by a number of anodes 1- 8 arrangedalong a supposed cylindric surface coaxial with the'eathode. The discharge space of the valve is penetrated by a constant magnetic field which is parallel with the axis of the cylindric' cathode and is symbolized by the indicated at 15. The magnetic field is directed towards the plane of the figure. n ne magnetic field s sufiicientIy strong man, as indicated on thie figure, all the anodes 198 have the n voltage, the-battery 1d, practically no el e as cu rent; yvillno y from the cathode to the an he lectrons emitted by the cathode williriste atd circle 'onn'd said cathode in paths indicated by the designati n i2. Owing" to space enact thns for d electron cloud 12 willprevent further emission of elec-' trons from the cathode. 1

If the potential of one of the electrodes, for example 1 in Fig. 1', decreases, an electron current wjll star t flo ingto said electrode, Fig. 2'. At further decrease (if the potential o f said anode, sfo that said potential will lie close to the cathode potential, the current to said elec} trode 1 decreases and the beam 12 is displaced towards the nearest preceding anode 8'. The neg'ative characteristic. PP f in? r a va ia ia ei if the voltage, i. e. thedecr'ease of the current with increasing voltage within said range, and the s epping, which can be obtained by lowering the voltage of a certain electrode below the wives; limit of the said variation rangefor the voltage, can be used for counting electric impiilses.

To make it possible to count im ulses, the device shown in Figs. 1 and 2 is suitably completed with a further electrode shaped as a cylinder surrounding the cathode 11 the anodes 1-8. Such a valve is shown in Fig. 3. Between two adjacent anodes 1 8 in saidv alve there is a hole thrtiiigh which the eleeirii bein'i 12 mi find its way to the cylindric electrode 16, instead of to the nearest preceding anode as in Figs. 1 and 2, when the potential on one of the anodes 18 decreases. As long as the concentric electrode 16, which obviously functions as receiving electrode for the electron beam, is positive, anode voltage from the battery 17, the different anodes 1-8, which obviously function as control electrodes, will not take up any current worth mentioning owing to a voltage decrease on the respective subsequent anode. If however the voltage on the receiving electrode 16 decreases to the neighbourhood of the cathode potential, the electron current will, at isolated voltage decrease on one of the control electrodes 1-8, however be obliged to pass over to the nearest preceding control electrode. If the control electrodes are suitably connected to resistances, this quality can in a suitable connection be used to count impulses which are in a suitable manner provided between the cathode 11 and the receiving electrode 16.

The valve shown in Fig. 3 has a drawback, and that is that the variations in the potential of the cylindric receiv ing electrode 16 affect the electric field round the cathode and therewith the strength of the cathode current. In order to reduce this detrimental effect the control electrodes 1-8 should be shaped so as to have a wide extent in a peripheral direction towards the cathode, as is shown in Fig. 4. The qualities of the valves are further favourably influenced if the mutual radial distance of the control electrodes 1-8 is constant. In Fig. 5 a valve is shown, in which the space existing between adjacent control electrodes has a constant width along the whole radial extent of said electrodes.

When utilizing such a valve to count electric impulses it is obvious that it is desirable to have a possibility to see in which one of the boxes existing between adjacent control electrodes the electron beam is, for example at the beginning and at the end of the counting process. According to the invention this can be achieved in a simple manner by the receiving electrode being coated with a material which becomes luminescent during electron bombardment. The receiving electrode will then gleam only at the place, indicated by the designation 13 in Fig. 4, where the electron beam falls onto it.

Different embodiments of electron valves according to the invention with visual indicating means are shown in Figs. 6-9.

In Fig. 6 a counting valve is shown, having ten receiving boxes limited by control electrodes 1'-8 shaped as rails parallel with the cathode 11. The valve is enclosed in a glass envelope 13 and provided with vacuum-tight inlets 20 for the different electrodes. The cylindric receiving electrode 16 is provided with a number of holes in its upper part, one in front of each one of the boxes existing between adjacent control electrodes. Two of these

holes

23 and 28 are shown in the side view of the valve comprised in Fig. 6. A portion of the electron beam-not shown on the drawingwhen steered into the corresponding box, is capable of penetrating said hole, Whereafter it impinges on a cone-shaped screen 19 coated on the inside with a luminescent material. Thus, if the valve is looked at from above, a luminous patch on the cone-shaped screen 19 will plainly indicate in which box the electron beam is steered.

The shape of the valve appears clearly from Fig. 7, which shows a modified embodiment of the screen 19 itself. This screen is not wholly coated with the luminescent material but only ten stripes of its surface are provided with such a coating. These stripes are in the figure indicated by 41-50 and are applied in a suitable manner in relation to the different holes 2130 on the receiving electrode 16. Due to the bending of the electron beam after it has issued from said holes under the influence of the magnetic field generated by the permanent magnet 31,'the said stripes do not lie in front of the corresponding holes but they are displaced or offset to one side. In the upper portion of the figure the electron beam 12 is shown when steered into the box between the control electrodes 1 and 2, whereby part of the beam issues from said box by the corresponding hole in the receiving electrode 16 to meet the stripe 41, on which a patch with a diameter corresponding to the hole will plainly gleam to indicate that the beam is in the 'box between said control electrodes.

lnstead of being round as in Figs. 6 and 7, the holes in the receiving electrodes may have any arbitrary shape. In order to prevent the patch formed by the electron beam from spreading, the screen shown in Fig. 7 is only partly coated with luminescent material. Such spreading can also be prevented by dividing by means of partition walls the channel formed between the cone-shaped screen and the receiving electrode into a number of chambers corresponding to the number of boxes. Such an embodiment is disclosed in the electrode system shown in Fig. 8, where the receiving electrode 16 is provided with triangular openings 21-30, from which partition walls forming tabs 51-66 have been bent between the electrode 16 and the screen 19. In said channel said tabs or partition walls limit a number of open topped chambers 4150', the oblique far end of which, as seen from the cathode, is formed by the screen 19 and coated with luminescent material.

' In the embodiment shown in Fig. 9 the receiving electrode 16 itself is on its external side, counted from the cathode, in the neighbourhood of the respective holes 214%), pro-vided with luminescent coatings 71-80. When the electron beam 12 issues from a hole, for example 21, it will, due to the influence of the magnetic field, be bent towards the external side of the receiving electrode, which it meets on the luminescent surface 71 arranged near said hole; the surface will thereby gleam on a patch corresponding to the section of the beam. A cone-shaped screen 19 is arranged round the upper part of the receiving electrode in the same manner as the screens shown in the preceding figures. In this case however, the screen 19 is not coated with any luminescent material but polished to shine as a mirror, so as to give upwards a refiectionof the patch formed on the external side of the receiving electrode owing tothe electron beam. If the valve is looked at from above, a reflection 65' of the gleaming patch will thus be visible and the position of the electron beam in the tube can be judged.

Detail-modifications of the shown and described embodiments of an electron valve according to the invention may naturally be made without the scope of the invention being departed from.

I claim:

1. Anelectron valve of the type described comprising in combination, an evacuated envelope, an elongated cylindrical receiving electrode in said envelope, means providing a constant magnetic field within the envelope and parallel to the axis of said electrode, a cylindrical cathode coaxially arranged in said electrode to emit electrons directed in a circular path by said field and a plurality of circumferentially spaced control electrodes intermediate the receiving electrode and the cathode, each control electrode extending longitudinally of and parallel to the cathode and receiving electrode and having substantial radial extent with its outer portion close to the receiving electrode, the envelope of the innermost portions of said control electrodes coaxially surrounding the cathode and means to separately connect a control electrode to a potential different from that of the other control electrodes to divert electrons from said cathode in a beam to the area of the receiving electrode exposed between such differently energized electrode and the adjacent control electrode preceding it in the direction of electron circulation.

2. The electron valve of claim 1 in which material adapted to luminesce when energized by a part of the electron beam frorn said cathode is'arranged at receiving electrode potential and positioned to be so energized as to indicate the particular area of the receiving electrode exposed between adjacent control electrodes which is receiving the beam.

3. The electron valve of claim 1 in which each area of the receiving electrode exposed to the cathode between adjacent control electrodes is provided with an aperture through which a part of the electron beam emitted from the cathode can pass when steered to a particular area and material adapted to luminesce when energized by said beam positioned beyond each aperture and at receiving electrode potential in the path of the beam passing through it.

4. The electron valve of claim 3 in which said material is applied to a cone shaped screen fixed to and surrounding the receiving electrode adjacent the apertures therein.

5. The device as claimed in claim 4 in which the whole inner area of the screen is coated with the luminescent material.

6. The device as claimed in claim 4 in which the inner area of the screen is coated with individual stripes of luminescent material each positioned to be struck by the electron beam passing through a particular aperture.

7. The device as claimed in claim 3 in which the outer side of the receiving electrode is provided with the luminescent material close to said apertures.

8. The device as claimed in claim 7 in which a cone shape reflecting screen is arranged externally of the receiving electrode to disclose the position of luminous patches on the outer surface of the receiving electrode from a position adjacent one end of the envelope.

9. The device as claimed in claim 4 in which the apertures are formed by tabs bent outwardly from the receiving electrode, said tabs forming partitions to divide the coated area of the screen into a number of parts corresponding and allotted to the respective apertures.

References Cited in the file of this patent UNITED STATES PATENTS w I W