GB725719A - Improvements in and relating to cathodes for electric discharge devices - Google Patents

Improvements in and relating to cathodes for electric discharge devices

Info

Publication number
GB725719A
GB725719A GB8242/53A GB824253A GB725719A GB 725719 A GB725719 A GB 725719A GB 8242/53 A GB8242/53 A GB 8242/53A GB 824253 A GB824253 A GB 824253A GB 725719 A GB725719 A GB 725719A
Authority
GB
United Kingdom
Prior art keywords
cathode
thoria
sleeve
heated
heater
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
GB8242/53A
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.)
General Electric Co
Original Assignee
General Electric Co
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 General Electric Co filed Critical General Electric Co
Publication of GB725719A publication Critical patent/GB725719A/en
Expired legal-status Critical Current

Links

Classifications

    • 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
    • H01J1/26—Supports for the emissive material

Abstract

725,719. Cathode materials and processing. GENERAL ELECTRIC CO. March 25, 1953 [April 1, 1952], No. 8242/53. Class 39 (1). Layers of thoria and of a carbide of one of the metals tantalum, tungsten, molybdenum are formed cn the respective sides of a thermionic cathode. A tantalum cathode 1 is fitted with a sleeve 3 which is grooved at the ends of a diameter for the passage of the heater-connecting wires to the terminal sleeve 5. The terminal 4 also supports the filament 2. A layer of carbide mixed with methyl cellulose is heated in a vacuum to 1700-1800‹C. to reduce the thickness from 0.5 microns to 0.001. Thoria is sprayed, painted or deposited by electrophoresis and the cathode again heated for 30 mins. in a vacuum so that carbon will diftuse though the sleeve 1 to reduce to thoria some of the thorium coating. Further reduction of the thoria is produced during the activation of the thermionic valve when the cathode is heated by the heater to 1700-2200‹C. for 10-90 fins. Dimensions of the electrode and details of the electrolyte are included in the Specification.
GB8242/53A 1952-04-01 1953-03-25 Improvements in and relating to cathodes for electric discharge devices Expired GB725719A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US279888A US2723363A (en) 1952-04-01 1952-04-01 Cathode and method of producing same

Publications (1)

Publication Number Publication Date
GB725719A true GB725719A (en) 1955-03-09

Family

ID=23070780

Family Applications (1)

Application Number Title Priority Date Filing Date
GB8242/53A Expired GB725719A (en) 1952-04-01 1953-03-25 Improvements in and relating to cathodes for electric discharge devices

Country Status (5)

Country Link
US (1) US2723363A (en)
BE (1) BE518861A (en)
DE (1) DE967715C (en)
FR (1) FR1073802A (en)
GB (1) GB725719A (en)

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2768321A (en) * 1955-05-02 1956-10-23 Rca Corp Indirectly heated electron emitter for power tubes and the like
BE571711A (en) * 1957-10-04
US3034479A (en) * 1957-10-17 1962-05-15 Larsh Apparatus for flow coating the slots of a slotted stator
DE1080700B (en) * 1958-05-17 1960-04-28 Deutsche Elektronik Gmbh Process for the production of an indirectly heated cathode, in particular for magnetrons with high oscillating power, and cathode produced according to this process
NL272248A (en) * 1960-12-15
GB1004776A (en) * 1961-03-15 1965-09-15 Gen Electric Improvements in cathode construction
DE1133835B (en) * 1961-12-16 1962-07-26 Telefunken Patent Process for the production of an indirectly heated cathode for an electrical discharge tube
US3475161A (en) * 1967-03-14 1969-10-28 Howmet Corp Method of forming cemented carbide coatings on metal surfaces by employing volatile,organic liquid solvents and organic binders
US3958146A (en) * 1974-02-08 1976-05-18 Gte Sylvania Incorporated Fast warm up picture tube cathode cap having high heat emissivity surface on the interior thereof
US3881126A (en) * 1974-03-06 1975-04-29 Gte Sylvania Inc Fast warm-up cathode assembly
USRE32918E (en) * 1983-03-11 1989-05-09 Technion, Inc. Heater/emitter assembly
US4569198A (en) * 1983-03-11 1986-02-11 Technion, Incorporated Heater/emitter assembly
US4730449A (en) * 1983-07-26 1988-03-15 Technion, Inc. Radiation transfer thrusters for low thrust applications
DE19828158C1 (en) * 1998-06-24 1999-11-25 Siemens Ag Indirectly heated cathode, especially for X-ray tube

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1886705A (en) * 1926-02-06 1932-11-08 Arsene N Lucian Indirect electron excitation for thermionic vacuum tubes
US2115828A (en) * 1935-04-13 1938-05-03 Bell Telephone Labor Inc Electron emitting cathode and method of preparation
DE710283C (en) * 1936-10-03 1941-09-09 Aeg Coating of tantalum carbide on non-emission electrodes of electrical discharge vessels and method for its application
DE715156C (en) * 1937-07-23 1941-12-16 Aeg Method for applying a coating of zirconium and / or niobium carbide or a coating made from an admixture of these carbides to tantalum carbide on electrodes that are not used for emission
US2284655A (en) * 1939-10-26 1942-06-02 Lorenz C Ag Electric discharge tube
NL149363C (en) * 1940-01-24
NL65083C (en) * 1942-02-06
US2438732A (en) * 1947-03-15 1948-03-30 Eitel Mcculough Inc Electron tube cathode

Also Published As

Publication number Publication date
US2723363A (en) 1955-11-08
BE518861A (en)
FR1073802A (en) 1954-09-29
DE967715C (en) 1957-12-05

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