GB685444A - Improvements relating to thermionic cathodes - Google Patents

Improvements relating to thermionic cathodes

Info

Publication number
GB685444A
GB685444A GB513/49A GB51349A GB685444A GB 685444 A GB685444 A GB 685444A GB 513/49 A GB513/49 A GB 513/49A GB 51349 A GB51349 A GB 51349A GB 685444 A GB685444 A GB 685444A
Authority
GB
United Kingdom
Prior art keywords
helix
cathode
aluminate
barium
barium aluminate
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB513/49A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
British Thomson Houston Co Ltd
Original Assignee
British Thomson Houston Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by British Thomson Houston Co Ltd filed Critical British Thomson Houston Co Ltd
Publication of GB685444A publication Critical patent/GB685444A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J9/00—Apparatus or processes specially adapted for the manufacture, installation, removal, maintenance of electric discharge tubes, discharge lamps, or parts thereof; Recovery of material from discharge tubes or lamps
    • H01J9/02—Manufacture of electrodes or electrode systems
    • H01J9/04—Manufacture of electrodes or electrode systems of thermionic cathodes
    • H01J9/042—Manufacture, activation of the emissive part
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J1/00—Details of electrodes, of magnetic control means, of screens, or of the mounting or spacing thereof, common to two or more basic types of discharge tubes or lamps
    • H01J1/02—Main electrodes
    • H01J1/13—Solid thermionic cathodes
    • H01J1/20—Cathodes heated indirectly by an electric current; Cathodes heated by electron or ion bombardment
    • H01J1/28—Dispenser-type cathodes, e.g. L-cathode
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J3/00—Details of electron-optical or ion-optical arrangements or of ion traps common to two or more basic types of discharge tubes or lamps
    • H01J3/02—Electron guns
    • H01J3/027—Construction of the gun or parts thereof

Abstract

685,444. Cathode ray tubes; cathode materials and processing. BRITISH THOMSON-HOUSTON CO., Ltd. Jan. 7, 1949 [Jan. 15, 1948], No. 513/49. Class 39(i) A thermionic cathode e comprises a wire helix 1 enclosing a fused body of electron emissive material 17. The material is preferably barium aluminate and the cathode is shown applied to an electron accelerator'in which the helix is of square cross-section and is supported in a channel-shaped shield and focusing member 3 by an intermediate channel-shaped member 4. The shield and cathode are in turn supported in a larger channel-shaped accelerator electrode 14. In one method of manufacturing the cathode, the barium aluminate in granular form is loaded into the helix and heated to about 1650‹C, preferably in an atmosphere of hydrogen, to melt the barium aluminate which then forms a solid, dense mass partially filling the helix. The process is repeated until the helix is completely filled. Alternatively, the helix may be immersed in liquid barium aluminate in an electrically heated boat, Fig. 5 (not shown) preferably also in an atmosphere of hydrogen. When removed from the boat and after cooling, the helix has a dense core of barium aluminate completely filling it. In both cases the barium aluminate extends between adjacent turns of the helix sufficiently to insulate them from each other so that the helix may serve as a heater. Other materials referred to are barium hydroxide, thorium aluminate and strontium aluminate. Dimensions of an example of a completed cathode are given.
GB513/49A 1948-01-15 1949-01-07 Improvements relating to thermionic cathodes Expired GB685444A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US2402A US2499192A (en) 1948-01-15 1948-01-15 Dispenser type cathode

Publications (1)

Publication Number Publication Date
GB685444A true GB685444A (en) 1953-01-07

Family

ID=21700589

Family Applications (1)

Application Number Title Priority Date Filing Date
GB513/49A Expired GB685444A (en) 1948-01-15 1949-01-07 Improvements relating to thermionic cathodes

Country Status (4)

Country Link
US (1) US2499192A (en)
BE (1) BE486753A (en)
FR (1) FR979177A (en)
GB (1) GB685444A (en)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2719244A (en) * 1952-01-25 1955-09-27 Westinghouse Electric Corp Electrical discharge tube
BE519027A (en) * 1952-04-09
FR1078606A (en) * 1953-04-02 1954-11-19 Csf Improvements to emissive cathodes
US3113236A (en) * 1959-06-23 1963-12-03 Philips Corp Oxide dispenser type cathode
US3105917A (en) * 1960-02-11 1963-10-01 Philips Corp Electric discharge device comprising an activated cold cathode
DE1217503B (en) * 1964-12-02 1966-05-26 Siemens Ag Storage cathode for electrical discharge vessels
US3405303A (en) * 1964-12-29 1968-10-08 Sylvania Electric Prod Arc discharge tube having an electrode which contains a light-emitting metal
US3706115A (en) * 1971-02-09 1972-12-19 Robert F Bleile Staple for sod and erosion control mattings
US4243624A (en) * 1979-05-21 1981-01-06 Exxon Research & Engineering Co. Method of making cathodes derived from ammonium-metal-chalcogen compounds

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL24414C (en) * 1926-06-09
US1813704A (en) * 1928-06-26 1931-07-07 Westinghouse Lamp Co Cathode
US1946603A (en) * 1929-05-09 1934-02-13 Electrons Inc Cathode for electrical discharge devices
US2007932A (en) * 1930-08-23 1935-07-09 Sirian Lamp Co Surge arrester
US2007926A (en) * 1930-10-21 1935-07-09 Sirian Lamp Co Light emitting unit
US2107945A (en) * 1934-11-20 1938-02-08 Gen Electric Cathode structure
US2175345A (en) * 1935-07-12 1939-10-10 Gen Electric Electric gaseous discharge device

Also Published As

Publication number Publication date
BE486753A (en)
US2499192A (en) 1950-02-28
FR979177A (en) 1951-04-23

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