US2367669A - Cathode structure - Google Patents

Cathode structure Download PDF

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Publication number
US2367669A
US2367669A US468199A US46819942A US2367669A US 2367669 A US2367669 A US 2367669A US 468199 A US468199 A US 468199A US 46819942 A US46819942 A US 46819942A US 2367669 A US2367669 A US 2367669A
Authority
US
United States
Prior art keywords
cathode
wires
rods
circumferentially
cathode structure
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 - Lifetime
Application number
US468199A
Other languages
English (en)
Inventor
Chevigny Paul Georges
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
Federal Telephone and Radio Corp
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
Priority to BE461543D priority Critical patent/BE461543A/xx
Application filed by Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Priority to US468199A priority patent/US2367669A/en
Priority to GB16958/43A priority patent/GB570468A/en
Application granted granted Critical
Publication of US2367669A publication Critical patent/US2367669A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • H01J1/22—Heaters

Definitions

  • This invention relates to improvements in cathode structure, and more particularly to a cathode for Vacuum tubes adapted to be heated by bombardment.
  • An object of this invention is to provide a novel unipotential cathode of high emission.
  • a further object of this invention is to form a built-up cathode which has a larger emitting surface than similar cathodes heretofore proposed.
  • a more specific object of this invention is to provide a substantially cylindrical cathode in which the cathode emitting surface is formed by a plurality of circumferentially juxtaposed rods or wires which when heated touch one another so as to form an effectively continuous emitting surface.
  • Fig. 1 is a vertical longitudinal section of a novel cathode structure formed in accordance with the present invention
  • Fig. 2 is a horizontal cross-sectional view taken along the line 22 of Fig. 1;
  • Fig. 3 is a partial cross-sectional view showing a modified structural detail.
  • the cathode emitting surface is formed of a plurality of longitudinally extending parallel rods or wires which may be made of thoriated tungsten or from equivalent material.
  • a sufficient number of the rods ID are circumferentially mounted in end supports i2 and It to form a substantially cylindrical cathode surface surrounding and coaxial with a centrally positioned heater coil it.
  • the rods It are preferably mounted in annular grooves of the end members 12 and M, as by Welding.
  • the rods are preferably slightly spaced from one another so that when they expand under this heating action, they will touch one another to form a continuous cathode surface.
  • the cathode will be of such a type that the rods Ill and will be heated by the filaments It by bombardment, although the invention is not intended to'be limited to this specific form of heating.
  • the filament I 6 is preferably supported by a suitable centrally positioned rod [8 while the cathode as a whole may be supported by a plurality of circumferentially supported rods 20 attached about the periphery of the cylindrical support 12. The ends of the filament, the rod l8 and the rods 2
  • heat screens may be provided at one or both ends of the cathode structure.
  • Fig. 1 shows an example of such heat screens at 22, these being attached in any suitable manner to the lower surface of the lower end member [4.
  • the manner in which the rods [0 may be circumferentially supported may be varied, if desired, for example in the manner illustrated in Fig. 2.
  • the rod H0 are connected about the periphery of an outwardly extending reverse flange I28 on the end of the support I I2.
  • a ring I30 surrounds the ends of the rods 1 l0 and holds them firmly in place against the surface of the flange I28.
  • the rods H0 will be slightly circumferentially spaced, to take care of the increase in diameter of the rods when heated.
  • An advantage of the structures illustrated in Figs. 1 and 2 lies in the fact that the rods forming the cathode surface being cut in short lengths can readily be carburized in advance before being assembled. Additionally, since in their heated condition the rods will be substantially tangent to one another, the emitting surface of the oathode is increased over a comparable cathode having a smooth cylindrical emitting surface.
  • the diameter of the rods is so chosen that the depth of the space between the two wires is small with respect to the distance between the cathode and grid. Particularly in the case of such tubes when used in pulse transmitters, this distance is of no importance, as the grid voltage will be very high and will easily draw electrons fr0mbetween the two rods.
  • a hollow, self-supporting cathode structure comprising a plurality of circumferentially arranged parallel wires, and separate means at opposite ends of said wires for holding them in their circumferentially arranged position.
  • a cathode structure comprising, in combination, a cylindrical cathode support, a plurality of wires connected at one end parallelto one another about one end of said support, and a cup-shaped member connected to and about the other ends of said wires.
  • a cathode structure comprising in combination, a cylindrical cathode support having one end formed with a longitudinally re-entrant annular notch, a plurality of wires welded at one end in said notch parallel to one another, and a cup-shaped member formed with a narrow annular groove receiving and supporting the other ends of said Wires.
  • a cathode structure comprising in combination, a cylindrical cathode support having one end formed with an outwardly turned reverse flange, a plurality of wires mounted at one end about the periphery of said flange, parallel with one another, a clamping ring fastened about one end of the wires, and means at the other end of the wires for holding them in their circumferentially arranged parallel positions.

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  • Electron Sources, Ion Sources (AREA)
US468199A 1942-12-08 1942-12-08 Cathode structure Expired - Lifetime US2367669A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
BE461543D BE461543A (ko) 1942-12-08
US468199A US2367669A (en) 1942-12-08 1942-12-08 Cathode structure
GB16958/43A GB570468A (en) 1942-12-08 1943-10-15 Indirectly heated thermionic cathodes for electron discharge devices

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US468199A US2367669A (en) 1942-12-08 1942-12-08 Cathode structure

Publications (1)

Publication Number Publication Date
US2367669A true US2367669A (en) 1945-01-23

Family

ID=23858816

Family Applications (1)

Application Number Title Priority Date Filing Date
US468199A Expired - Lifetime US2367669A (en) 1942-12-08 1942-12-08 Cathode structure

Country Status (3)

Country Link
US (1) US2367669A (ko)
BE (1) BE461543A (ko)
GB (1) GB570468A (ko)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2774941A (en) * 1952-11-14 1956-12-18 Raytheon Mfg Co Communication systems
US2973449A (en) * 1957-10-23 1961-02-28 Philips Corp Electric discharge tube

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2774941A (en) * 1952-11-14 1956-12-18 Raytheon Mfg Co Communication systems
US2973449A (en) * 1957-10-23 1961-02-28 Philips Corp Electric discharge tube

Also Published As

Publication number Publication date
GB570468A (en) 1945-07-09
BE461543A (ko)

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