GB591401A - Improvements in and relating to the manufacture of spiral filamentary cathodes for electron discharge devices - Google Patents

Improvements in and relating to the manufacture of spiral filamentary cathodes for electron discharge devices

Info

Publication number
GB591401A
GB591401A GB5536/44A GB553644A GB591401A GB 591401 A GB591401 A GB 591401A GB 5536/44 A GB5536/44 A GB 5536/44A GB 553644 A GB553644 A GB 553644A GB 591401 A GB591401 A GB 591401A
Authority
GB
United Kingdom
Prior art keywords
sleeve
mandrel
winding
cathode
graphite
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
GB5536/44A
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.)
STC PLC
Original Assignee
Standard Telephone and Cables PLC
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 Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Publication of GB591401A publication Critical patent/GB591401A/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

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Microwave Tubes (AREA)
  • Solid Thermionic Cathode (AREA)
  • Discharge Lamp (AREA)

Abstract

591,401. Cementation; heat-treating metals. STANDARD TELEPHONES and CABLES, Ltd. March 24, 1944, No. 5536. Convention date, Feb. 13,1943. [Class 72] [Also in Group XL] A spiral filamentary cathode for an electron discharge device is produced by winding the cathode into the desired shape on a mandrel, setting the windings, e.g., by heating the mandrel in an hydrogen atmosphere, preferably by high frequency current, at 2,000‹C, removing the set winding from the mandrel and coating it with a colloidal graphite solution ; covering the inside of a smooth graphite sleeve with the same solution, sliding the filament into the sleeve, heating the sleeve &c. in an hydrogen atmosphere at 2,000‹C until a forty per cent. carburisation of the cathode is obtained and then removing the cathode from the sleeve. The winding 10 of pure tungsten wire or of thoriated tungsten wire is wound on a mandrel of molybdenum before heating by high frequency current at 2,000‹C and after removal from the mandrel is coated with colloidal solution of graphite in water and slid into the smooth bore of a graphite sleeve 14 which is then coated with the same solution. The sleeve 14 with the winding 10 is then placed in a high frequency heating furnace and heated until the desired carburisation has taken place. The carburised winding is then removed from the sleeve 14. Specification 569,048 is referred to.
GB5536/44A 1943-02-13 1944-03-24 Improvements in and relating to the manufacture of spiral filamentary cathodes for electron discharge devices Expired GB591401A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US591401XA 1959-06-10 1959-06-10

Publications (1)

Publication Number Publication Date
GB591401A true GB591401A (en) 1947-08-18

Family

ID=22021092

Family Applications (1)

Application Number Title Priority Date Filing Date
GB5536/44A Expired GB591401A (en) 1943-02-13 1944-03-24 Improvements in and relating to the manufacture of spiral filamentary cathodes for electron discharge devices

Country Status (2)

Country Link
BE (1) BE591401A (en)
GB (1) GB591401A (en)

Also Published As

Publication number Publication date
BE591401A (en) 1960-09-16

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