US2432789A - Cathode assembly - Google Patents

Cathode assembly Download PDF

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Publication number
US2432789A
US2432789A US600028A US60002845A US2432789A US 2432789 A US2432789 A US 2432789A US 600028 A US600028 A US 600028A US 60002845 A US60002845 A US 60002845A US 2432789 A US2432789 A US 2432789A
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heater
cathode
openings
disk
tube
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Expired - Lifetime
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US600028A
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O'larte Rudolph
Speck Kurt
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Jacques Kreisler Manufacturing Corp
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Jacques Kreisler Manufacturing Corp
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Priority to US600028A priority Critical patent/US2432789A/en
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J1/00Details 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
    • H01J1/02Main electrodes
    • H01J1/13Solid thermionic cathodes
    • H01J1/20Cathodes heated indirectly by an electric current; Cathodes heated by electron or ion bombardment

Definitions

  • This invention relates to a cathode assembly :for a-cathode ray tube or thelike.
  • pro- vide improved means for supporting the heat- :ingelementof Zthecathode and to facilitate the assembly of said heatingelement with the oathode and the tubular member in which the cath- .odeismounted.
  • Fig. .3 is .a -view similar to Fig. .2 showing ,an-
  • Fig. .4 is an end .view of retaining means formh s par of the cathode assembly .of th es invention
  • the cathode assembly 1.0 which is intended for use ,ina cathode ray-tube aspart oftheeleotron gun, comprises .a tubular member 12 .formed of sheet metal. Said.tllbularmemberis preferably of the constructionillustrated in our application, Serial .-.No. 5.8.8230, filed April 13.
  • a sheet metal disk provided with .an electron aperture 22 is positioned and secured at one end of tubular memb r .12, as ad sclosedi ereina d in sa d apand suppo ted h ineiilation mem 35 he einafter more specifi al y descr bed, wh c i .leasably heldih bns iiiintby partsof the retain- 6 Claims. (01. 250-162) ing means 30.
  • the retaining means .370 isformed of resilient sheet metal and comprises ,a forward annular portion 36 having a peripheral flange 38 and a plurality of resilient arms 40 which extend longitudinally of tubular member I12 inengagement with theinner surface .thereof.
  • Each of said arms .40 is provided .with an outwardly pressed transverse rib 42 positioned so that itengages tubular member 12 in an annular groove 44 pressed therein.
  • Annular portion .36 of the retaining means is provided with a plurality .of integral struck .out spring elements or fingers-46 which resilientlyengage the cathode carrying disk 2-6 and press the latter against the spacing member ,28, said spacing member .being thereby pressed against the apertured disk 29.
  • the retaining means ,311 as thus far described is ;the same as inthe cathodeassembly ofxourabove mentioned application. ,In accordance with the present invention, however, the arm 4
  • arms 40 of retaining means 31! are provided with out- Wardly pressed transverse ribs .48 r and insulation upporting member .34, which as here shown is in the ..form of a .diskkis provided with circumierentially spaced .notches :50 in which said ribs 4,8 are movably positioned, respectively, and resiliently-engage said insulation supporting member 34 ,for holding the latter on tubular member
  • Th insulation supportine member 34 is provided with terminal members 52.
  • Each of said terminal members comp ises a.
  • the insulation supporting member .34 is provided with a .pair of openings 56 in which the terminal members 52 are positioned, the companion projections 5 10f each terminal member engaging the inner and outer sides, respectively,
  • the st ips .58 are inserted in position aft r e t rminal members are positioned in the companion openin gs 56 and that after the terminal members are positioned in their companion nehi ese member 34. strips 58 hold the opposite sides of the terminal members against the adjacent sides of the companion openings 56.
  • the ends of the heater element 32 are secured to the inner ends of the companion terminals 52, preferably by positioning the end of the heater element between the inner end portions of the opposite sides of the companion terminal member and by welding the end of the heater element to said end portions of the companion terminal member. It will be understood that, as usual, the heater element is coated with insulation material, except at the ends which are secured to the terminal members 52.
  • the heater element 32 is assembled with the supporting member 34 and forms a unitary subassembly therewith.
  • the sub-assembly comprising the supporting member 34 with the attached heater element 32 is mounted on tubular member I2, heater element 32 being positioned within the tubular cathode 24 andsupporting member 3 3 being resiliently engaged by the ribs 48 of the retaining means 30.
  • each terminal member 52A is formed of a piece of wire, which is preferably of circular crosssection, bent into the form shown in Fig. 3 to provide the laterally spaced legs 64 and 66 which are received in the companion openings 60 and 62.
  • the outer bent end portion of the wire is twisted for providing the outer terminal portions 68, and the inner end portions of legs 64 and 66 are twisted together as indicated at 10, one of said inner end portions being longer than the other and bent into a transversely extending portion I2 to which the ends of the heater element 32 are welded or otherwise suitably secured. It will be noted that end portions 14 of the heater element 32 may extend into companion openings 62, respectively.
  • the terminal members 52A are secured to the supporting member 34A and then the ends of the heater element are secured to the inner transverse terminal portion 12, respectively, at such points longitudinall of the end portions of the heater element that the forward end of the latter is spaced properly from the inner surface of the forward end of the tubular cathode 24, openings 62 providing means to receive the end portions of the heater element which extend rearwardly of the terminal portion 12.
  • This construction provided a convenient means for adjusting the position of the heater element 32 longitudinally of cathode 24 and also facilitates the attachment of the terminal members to the supporting member 34A and to the end of the heater element.
  • a sub-assembly for a cathode which comprises a tube provided with an electron aperture at one end thereof, a tubular cathode positioned within said tube axially thereof, and a heater in said cathode; said sub-assembly comprising said heater and a support therefor, said support comprising an insulation disk provided with two sets of spaced openings, each set comprising two openings and the openings of the two sets being symmetrically disposed at opposite sides, respectively, of the axis of said disk, a pair of terminal members secured to said disk, one of said terminal members having portions extending through the two openings, respectively, of one of said sets and electrically connected to one end of said heater and the other of said terminal members having portions extending through the two openings, respectively, of the other set and electrically connected to the other end of said heater.
  • a sub-assembly for a cathode which comprises a tube provided with an electron aperture at one end thereof, a tubular cathode positioned within said tube axially thereof, and a heater in said cathode; said sub-assembly comprising said heater and a support therefor, said support comprising an insulation disk rovided with two sets of spaced openings, each set comprising two openings and the openings of the two sets being symmetrically disposed at opposite sides, respectively, of the axis of said disk, a pair of terminal members secured to said disk, one of said terminal members having portions extending through the two openings, respectively, of one of said sets and electrically connected to one end portion of said heater and the other of said terminal members having portions extending through the two openings, respectively, of the other set and electrically connected to the other end of said heater, one of the openings of each set providing a space to receive an end portion of the heater.
  • a sub-assembly for a cathode which comprises a tube provided with an electron aperture at one end thereof, a tubular cathode positioned within said tube axially thereof, and a heater in said cathode; said sub-assembly comprising said heater and a support therefor, said support comprising an insulation disk provided with a pair of openings symmetrically disposed in spaced relation at opposite sides of the axis of the disk.
  • each of said terminal members comprising a bent wire having two sides extending through one of said openings, one of said sides having spaced lateral projections engaging the disk at the opposite sides, respectivel thereof for preventing movement of the terminal member axially of the disk.
  • a cathode assembly which comprises a tube provided with an electron aperture at one end thereof, a tubular cathode positioned within said tube axially thereof, and a heater in said cathode; the combination with said first mentioned tube and said heater of an insulation member which supports said heater and is positioned at and closes the other end of said first mentioned tube, terminals carried by said member and electrically connected to said heater, said insulation member comprising a disk having peripherally spaced notches in its edge, and a plurality of spring arms carried by said tube and releasably engageable with said disk in said notches, respectively, for holding the disk in position.
  • a cathode assembly which comprises a tube provided with an electron aperture at one end thereof, a, tubular cathode positioned within said tube axially thereof, and a heater in said cathode; the combination with said first mentioned tube and said heater of an insulation mem ber which supports said heater and is positioned at and closes the other end of said first mentioned tube, terminals carried by said member and electrically connected to said heater, said disk being provided with two sets of spaced openings, the openings of the two sets being symmetrically disposed at opposite sides of the axis of said disk, a pair of terminal members secured to said disk, each of said terminal members having portions extending through the openings of one of said sets and electrically connected to an end portion of said heater.
  • a cathode assembly which comprises a tube provided with an electron aperture at one end thereof, a tubular cathode positioned within said tube axially thereof, and a heater in said cathode; the combination with said first mentioned tube and said heater of an insulation member which supports said heater and is positioned at and closes the other end of said first mentioned tube, terminals carried by said member and electrically connected to said heater, said disk being provided with a pair of openings symmetrically REFERENCES CITED

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  • Electrodes For Cathode-Ray Tubes (AREA)

Description

Dec. 16, 1947.
R. OLAR.TE' E1" AL CATHODE AS SEMBLY Filed June 18, 1945 INVENTOR. RUDOLPH O'LARTE By KURT SPECK A 7' TO/PNEV Patented Dec. 16, 1947 UNITED STATES PATENT OFFICE :CATHODE ASSEMBLY Rudolph OiLarte, Rego Park, N. Y., and Kurt Speck, Palisades Park, N. J.,
assignors to Jacques 'Kreisler Manufacturing Corporation, North Bergen, N. J., a corporation of New Jersey Application June 18, 1945, Serial No. 600,028
This invention relates to a cathode assembly :for a-cathode ray tube or thelike.
Oneobject of the present invention is to pro- =vide improved means for supporting the heat- :ingelementof Zthecathode and to facilitate the assembly of said heatingelement with the oathode and the tubular member in which the cath- .odeismounted.
sion .of a .cathode assembly in which the heater element;is carried Joyreleasablyattached support- .in g means to ,facilitate =replacementof .the heatins ement in the cathod -assem ly.
Fig. .3 is .a -view similar to Fig. .2 showing ,an-
other formofthe invention;
Fig. .4 is an end .view of retaining means formh s par of the cathode assembly .of th es invention;
a sectiona view ten the i e of Elia-=4- Referring now to 1. the drawings in detail, the cathode assembly 1.0, which is intended for use ,ina cathode ray-tube aspart oftheeleotron gun, comprises .a tubular member 12 .formed of sheet metal. Said.tllbularmemberis preferably of the constructionillustrated in our application, Serial .-.No. 5.8.8230, filed April 13. 9 and ompris .two semi-cylindrical parts ,M and L6 having lateral extensions [8 which definesmail tubular .parts for mountingthe cathodeassembly on insulation rods ,(not shown) provided in the electron gun mounted in thecathode ray tube. A sheet metal disk provided with .an electron aperture 22 is positioned and secured at one end of tubular memb r .12, as ad sclosedi ereina d in sa d apand suppo ted h ineiilation mem 35 he einafter more specifi al y descr bed, wh c i .leasably heldih bns iiiintby partsof the retain- 6 Claims. (01. 250-162) ing means 30. The retaining means .370 isformed of resilient sheet metal and comprises ,a forward annular portion 36 having a peripheral flange 38 and a plurality of resilient arms 40 which extend longitudinally of tubular member I12 inengagement with theinner surface .thereof. Each of said arms .40 is provided .with an outwardly pressed transverse rib 42 positioned so that itengages tubular member 12 in an annular groove 44 pressed therein. Annular portion .36 of the retaining means is provided with a plurality .of integral struck .out spring elements or fingers-46 which resilientlyengage the cathode carrying disk 2-6 and press the latter against the spacing member ,28, said spacing member .being thereby pressed against the apertured disk 29.
The retaining means ,311 as thus far described is ;the same as inthe cathodeassembly ofxourabove mentioned application. ,In accordance with the present invention, however, the arm 4|] of retaining means 30 is provided with integral parts which releasably engage the heater .support 34 rfor holding the latter ;in position .on tubular member l2.
More specifically, s ,here shown, arms 40 of retaining means 31! are provided with out- Wardly pressed transverse ribs .48 r and insulation upporting member .34, which as here shown is in the ..form of a .diskkis provided with circumierentially spaced .notches :50 in which said ribs 4,8 are movably positioned, respectively, and resiliently-engage said insulation supporting member 34 ,for holding the latter on tubular member Th insulation supportine member 34 is provided with terminal members 52. Each of said terminal members comp ises a. bent flat wire provided with .a pair of spaced lateral projections 54., The insulation supporting member .34 is provided with a .pair of openings 56 in which the terminal members 52 are positioned, the companion projections 5 10f each terminal member engaging the inner and outer sides, respectively,
of member 34 (for holding the terminal member against movement transversely of the plane of member .3 5. Metal strips 58 are positioned between the opposite sides of each terminal member 52 and are welded or otherwise secured to said terminal members ,Vfor preventing movement of the opposite sidesof said terminal members, re-
sp t ve y, toward ach other. .It will be understood that the st ips .58 are inserted in position aft r e t rminal members are positioned in the companion openin gs 56 and that after the terminal members are positioned in their companion nehi ese member 34. strips 58 hold the opposite sides of the terminal members against the adjacent sides of the companion openings 56. As shown in Fig. 2, the ends of the heater element 32 are secured to the inner ends of the companion terminals 52, preferably by positioning the end of the heater element between the inner end portions of the opposite sides of the companion terminal member and by welding the end of the heater element to said end portions of the companion terminal member. It will be understood that, as usual, the heater element is coated with insulation material, except at the ends which are secured to the terminal members 52.
The heater element 32 is assembled with the supporting member 34 and forms a unitary subassembly therewith. In producing the complete cathode assembly, the sub-assembly comprising the supporting member 34 with the attached heater element 32 is mounted on tubular member I2, heater element 32 being positioned within the tubular cathode 24 andsupporting member 3 3 being resiliently engaged by the ribs 48 of the retaining means 30.
The construction illustrated in Fig. 3 is the same as described above except in respect to the terminals and in respect to the manner in which the heating element 32 is attached to the insulation supporting member. As here shown, the insulation supporting member or disk 34A instead of being provided with one opening for each terminal member is provided with a pair of openings 60 and 62 for each terminal member, openings 62 having an additional function which will presently appear. Each terminal member 52A is formed of a piece of wire, which is preferably of circular crosssection, bent into the form shown in Fig. 3 to provide the laterally spaced legs 64 and 66 which are received in the companion openings 60 and 62. The outer bent end portion of the wire is twisted for providing the outer terminal portions 68, and the inner end portions of legs 64 and 66 are twisted together as indicated at 10, one of said inner end portions being longer than the other and bent into a transversely extending portion I2 to which the ends of the heater element 32 are welded or otherwise suitably secured. It will be noted that end portions 14 of the heater element 32 may extend into companion openings 62, respectively. In manufacturing the sub-assembly illustrated in Fig. 3, the terminal members 52A are secured to the supporting member 34A and then the ends of the heater element are secured to the inner transverse terminal portion 12, respectively, at such points longitudinall of the end portions of the heater element that the forward end of the latter is spaced properly from the inner surface of the forward end of the tubular cathode 24, openings 62 providing means to receive the end portions of the heater element which extend rearwardly of the terminal portion 12. This construction provided a convenient means for adjusting the position of the heater element 32 longitudinally of cathode 24 and also facilitates the attachment of the terminal members to the supporting member 34A and to the end of the heater element.
It will be understood that various changes in the details of construction and in the arrangement of parts may be made without departing from the underlying idea or principles of the present invention within the scope of the appended claims, and it will be noted that the present application is a continuation-in-part of our above mentioned application, Serial Number 588,230.
Having thus described our invention, what we claim and desire to secure by Letters Patent is:
1. A sub-assembly for a cathode which comprises a tube provided with an electron aperture at one end thereof, a tubular cathode positioned within said tube axially thereof, and a heater in said cathode; said sub-assembly comprising said heater and a support therefor, said support comprising an insulation disk provided with two sets of spaced openings, each set comprising two openings and the openings of the two sets being symmetrically disposed at opposite sides, respectively, of the axis of said disk, a pair of terminal members secured to said disk, one of said terminal members having portions extending through the two openings, respectively, of one of said sets and electrically connected to one end of said heater and the other of said terminal members having portions extending through the two openings, respectively, of the other set and electrically connected to the other end of said heater.
2. A sub-assembly for a cathode which comprises a tube provided with an electron aperture at one end thereof, a tubular cathode positioned within said tube axially thereof, and a heater in said cathode; said sub-assembly comprising said heater and a support therefor, said support comprising an insulation disk rovided with two sets of spaced openings, each set comprising two openings and the openings of the two sets being symmetrically disposed at opposite sides, respectively, of the axis of said disk, a pair of terminal members secured to said disk, one of said terminal members having portions extending through the two openings, respectively, of one of said sets and electrically connected to one end portion of said heater and the other of said terminal members having portions extending through the two openings, respectively, of the other set and electrically connected to the other end of said heater, one of the openings of each set providing a space to receive an end portion of the heater.
3. A sub-assembly for a cathode which comprises a tube provided with an electron aperture at one end thereof, a tubular cathode positioned within said tube axially thereof, and a heater in said cathode; said sub-assembly comprising said heater and a support therefor, said support comprising an insulation disk provided with a pair of openings symmetrically disposed in spaced relation at opposite sides of the axis of the disk. a pair of terminal members secured in said openings, respectively, and electrically connected to the ends of said heater, each of said terminal members comprising a bent wire having two sides extending through one of said openings, one of said sides having spaced lateral projections engaging the disk at the opposite sides, respectivel thereof for preventing movement of the terminal member axially of the disk.
4. In a cathode assembly which comprises a tube provided with an electron aperture at one end thereof, a tubular cathode positioned within said tube axially thereof, and a heater in said cathode; the combination with said first mentioned tube and said heater of an insulation member which supports said heater and is positioned at and closes the other end of said first mentioned tube, terminals carried by said member and electrically connected to said heater, said insulation member comprising a disk having peripherally spaced notches in its edge, and a plurality of spring arms carried by said tube and releasably engageable with said disk in said notches, respectively, for holding the disk in position.
5. In a cathode assembly which comprises a tube provided with an electron aperture at one end thereof, a, tubular cathode positioned within said tube axially thereof, and a heater in said cathode; the combination with said first mentioned tube and said heater of an insulation mem ber which supports said heater and is positioned at and closes the other end of said first mentioned tube, terminals carried by said member and electrically connected to said heater, said disk being provided with two sets of spaced openings, the openings of the two sets being symmetrically disposed at opposite sides of the axis of said disk, a pair of terminal members secured to said disk, each of said terminal members having portions extending through the openings of one of said sets and electrically connected to an end portion of said heater.
6. In a, cathode assembly which comprises a tube provided with an electron aperture at one end thereof, a tubular cathode positioned within said tube axially thereof, and a heater in said cathode; the combination with said first mentioned tube and said heater of an insulation member which supports said heater and is positioned at and closes the other end of said first mentioned tube, terminals carried by said member and electrically connected to said heater, said disk being provided with a pair of openings symmetrically REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,797,990 Lucian Mar. 24, 1931 2,386,790 Gaun et a1 Oct. 16, 1945 2,391,780 Hillier Dec. 25, 1945 2,393,057 OLarte et a1 Jan. 15, 1945 FOREIGN PATENTS Number Country Date 432,970 Great Britain Aug. 7, 1935
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2582454A (en) * 1950-05-13 1952-01-15 Du Mont Allen B Lab Inc Cathode grid assembly
US2623090A (en) * 1947-12-19 1952-12-23 Sylvania Electric Prod Electron discharge device of the disk seal type
US2932755A (en) * 1956-01-30 1960-04-12 Applied Radiation Corp Electron gun and cathode
US3601651A (en) * 1970-01-09 1971-08-24 Motorola Inc Replacement cathode assembly

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1797990A (en) * 1926-02-06 1931-03-24 Arsene N Lucian Heater construction for cathodes
GB432970A (en) * 1933-02-10 1935-08-07 Fernseh Ag Improvements in or relating to cathode-ray tubes
US2386790A (en) * 1944-11-29 1945-10-16 Sylvania Electric Prod Electron gun and the like
US2391780A (en) * 1943-10-13 1945-12-25 Rca Corp Electron discharge device
US2393057A (en) * 1944-01-18 1946-01-15 Jacques Kriesler Mfg Corp Cathode assembly

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1797990A (en) * 1926-02-06 1931-03-24 Arsene N Lucian Heater construction for cathodes
GB432970A (en) * 1933-02-10 1935-08-07 Fernseh Ag Improvements in or relating to cathode-ray tubes
US2391780A (en) * 1943-10-13 1945-12-25 Rca Corp Electron discharge device
US2393057A (en) * 1944-01-18 1946-01-15 Jacques Kriesler Mfg Corp Cathode assembly
US2386790A (en) * 1944-11-29 1945-10-16 Sylvania Electric Prod Electron gun and the like

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2623090A (en) * 1947-12-19 1952-12-23 Sylvania Electric Prod Electron discharge device of the disk seal type
US2582454A (en) * 1950-05-13 1952-01-15 Du Mont Allen B Lab Inc Cathode grid assembly
US2932755A (en) * 1956-01-30 1960-04-12 Applied Radiation Corp Electron gun and cathode
US3601651A (en) * 1970-01-09 1971-08-24 Motorola Inc Replacement cathode assembly

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