US3160946A - Electrical heaters - Google Patents

Electrical heaters Download PDF

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Publication number
US3160946A
US3160946A US14471A US1447160A US3160946A US 3160946 A US3160946 A US 3160946A US 14471 A US14471 A US 14471A US 1447160 A US1447160 A US 1447160A US 3160946 A US3160946 A US 3160946A
Authority
US
United States
Prior art keywords
mandrel
spiral
wire
heater
coil
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
US14471A
Other languages
English (en)
Inventor
Jr Herbert F Dickson
Haas Paul
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.)
GTE Sylvania Inc
Original Assignee
Sylvania Electric Products Inc
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 NL262042D priority Critical patent/NL262042A/xx
Priority to US3097419D priority patent/US3097419A/en
Priority to US14470A priority patent/US3092748A/en
Application filed by Sylvania Electric Products Inc filed Critical Sylvania Electric Products Inc
Priority to US14471A priority patent/US3160946A/en
Priority to GB6534/61A priority patent/GB908096A/en
Priority to DES72903A priority patent/DE1186559B/de
Priority to FR855255A priority patent/FR1287645A/fr
Priority to US287401A priority patent/US3277685A/en
Application granted granted Critical
Publication of US3160946A publication Critical patent/US3160946A/en
Assigned to NORTH AMERICAN PHILIPS CONSUMER ELECTRONICS CORP. reassignment NORTH AMERICAN PHILIPS CONSUMER ELECTRONICS CORP. ASSIGNS ITS ENTIRE RIGHT TITLE AND INTEREST, UNDER SAID PATENTS AND APPLICATIONS, SUBJECT TO CONDITIONS AND LICENSES EXISTING AS OF JANUARY 21, 1981. (SEE DOCUMENT FOR DETAILS). Assignors: GTE PRODUCTS CORPORATION A DE CORP.
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
    • 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
    • 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
    • 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
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J29/00—Details of cathode-ray tubes or of electron-beam tubes of the types covered by group H01J31/00
    • H01J29/02—Electrodes; Screens; Mounting, supporting, spacing or insulating thereof
    • H01J29/04—Cathodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J29/00—Details of cathode-ray tubes or of electron-beam tubes of the types covered by group H01J31/00
    • H01J29/46—Arrangements of electrodes and associated parts for generating or controlling the ray or beam, e.g. electron-optical arrangement
    • H01J29/48—Electron guns
    • H01J29/485—Construction of the gun or of parts thereof
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/49082—Resistor making
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/49082—Resistor making
    • Y10T29/49087—Resistor making with envelope or housing
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/49082—Resistor making
    • Y10T29/49087—Resistor making with envelope or housing
    • Y10T29/49096—Resistor making with envelope or housing with winding

Definitions

  • This invention relates to heaters for electrical devices and more particularly to heaters adapted for use with thermionic cathodes of the type employed in electron tubes.
  • a low heater power type of cathode assembly may be used in electron tubes.
  • One form of such a heater-cathode assembly employs an insulated heater Wire embedded in the cathode base.
  • the cathode base metal material in powdered form is deposited about the heater wire and subsequently the powder is pressed into a pellet and sintered.
  • the heater should physically be uniformly and symmetrically placed, there should be no shorted sections of the heater, and the heater-cathode leakage should be a minimum.
  • the fabrication of the heater itself is an important factor in. achieveing the requirements enumerated above.
  • the heater wire should be formed in to a configuration to provide a relatively large amount of wire within the pellet, and the configuration should be symmetrical with uniform sectional spacings.
  • the insulating coating should be of uniform thickness over the entire embedded heater portion; 7
  • the foregoing objects are achieved in one aspect of the invention by the provision of a process and apparatus for forming a-spiral reverse coil wound heater.
  • the resistance heater wire is spiral wound up on a mandrel and this wire spiral and mandrel assembly are subsequently twisted into a reverse wound flat coil with substantially uniformly spaced wraps.
  • the mandrel is then removed and the heater Wire spiral is coated withinsulating material.
  • the mandrel is placed in a chuck and twisted with the ends of the mandrel arrested from rotational movement by stop pins.
  • FIG. 1 illustrates a length of heater wire spiral wound upon a mandrel
  • FIG. 2 shows the heater coil winding device
  • FIG. 3 is an enlarged top view of the heater winding chuck employed with the device of FIG. 2;
  • FIG. 4 illustrates a cross sectional view of the heater winding device
  • FIGS. 5, 6 and 7 illustrate the manner of forming the reverse heater coil
  • FIG. 8 illustrates the method of annealing the formed heater coil
  • FIG. 9 shows the manner of removing the mandrel from the heater spiral
  • FIG. 10 illustrates the heater coating operation
  • FIG. 11 is a plan view of a finished spiral reverse coil wound flat heater.
  • FIG. 11 a spiral reverse wound substantially flat coiled heater 13 is shown in FIG. 11.
  • the heater resistance wire 15 is formed into a spiral which is in turn twisted as a reverse wound coil.
  • Each turn of the spiral is coated with an electrical insulating material 17 except the last several turns.
  • the straight wire ends 19 are left uncoated to allow for welding to the heater power supply leadswhen employed in an electron tube.
  • Heater 13 is uniquely adapted to provide maximum heat for a given area with minimum power. Due to its relatively small size, compactness and uniform spacing and symmetry, the heater is suitable for use in an indirectly heated cathode assembly wherein the heater is embedded in the cathode base material.
  • FIG. 1 illustrates a spiral length of heater wire 15 which has been selected to provide the heat necessary for a given application at a given power rating.
  • the wire, wire may be tungsten, is Wound up a mandrel 21 made of, for instance, molybdenum.
  • the diameter of the wire, turns per inch of the spiral, and length ofthe heater can be varied in order to produce the desired electrical characteristics.
  • the wire 15 is preferably stretched beyond the elastic limit so. that the initial spiral shape will be substantially maintained after mandrel 21 has been removed as will be hereafter described.
  • the mandrel and wire spiral assembly 22 are subsequently formed or twisted into a substantially flat reverse wound coil.
  • a winding device 23 is provided for the purpose of accomplishing thisreverse winding operation. Referring to FIGS. 2' through 7, device 23 comprises a cylindrical block 25 having an aperture 27 extending longitudinally therethrough; The upper heater supporting surface 29 may be tapered. a slight amount, e.g., several degrees, radically symmetrically downward from aperture 27 to prevent the Wire spiral from climbing over itself during the twisting operation.
  • pins 31 preferably exceed the height of the spiral of wire and are oppositely disposed from and equally radially spaced'from the center of aperture 27.
  • the pins maybe permanently located as shown. However, for larger or more intricate coil configurations, it may be desirable to either move the pins radially during the winding operation surface 29.
  • Block 25 rests upon a cylindrical base 33 having a rod.
  • the upper end of the rod has a chuck 36 formed with a spiral and mandrel assembly receiving slot 37 defined by laterally spaced slot walls 39.
  • the opposed outside edges 41 of the walls are recessedfrom the rod periphery and are curved to provide the initial coil wrap configuration.
  • the height of the walls preferably exceed the diameter of the wire spiral. Since block 25 merely rests upon base 33, these parts may be rotated relative to one another. The amount of rotation of, for instance, base 33 or chuck 36 relative to block 25 may be ascertained from pointer 43 and markings 45. Also, base 33 and block 25 may reciprocate longitudinally relative to one another so that chuck 36 can be retracted to a mandrel assembly release position.
  • assembly 22 is first placed within slot 37 as shown in FIG. 2.
  • a symmetrical reverse coil such as is illustrated in FIGS. 7 and 11
  • the center of assembly 22 is positioned at the center of the slot.
  • the initial partial Wrap of the coil is achieved by applying tension to the mandrel and rotating base 33 toprovide rotation of chuck 36, FIG. 5.
  • the tension may be'applied by holding the ends of mandrel 21 to provide drag and therefor bending around the edges 41 of Walls 39, or it may be accomplished by pressing downwardly against the spiral and mandrel toachieve the same results.
  • chuck '36 isfurther rotated until assembly 22 contacts arresting pins 31.
  • assembly 22 After assembly 22 has been wound into a reverse coil, it is placed in an oven (not shown) and-fired between flat tungsten plates 47, see FIG. 8.
  • the firing operation may be performed in a wet hydrogen reducing atmosphere in accordance-with the temperature-time relationship reremoves the mandrel by selective etching, see FIG. '9.
  • a suitable solution such as one consisting of 50 percent nitric acid, 30 percent sulfuric acid and 20'percent water;
  • the reverse wound coil of wire may be subsequently rinsed in deionized water and subsequently electrophoretically coatedin tank 50 with the insulating material 17.
  • the coil of wire 15 is held in electrode 51, FIG. 10, so that the area'tobe coated is exposed to coating bath 53, which may consist of a dispersion. of aluminumoxide'in a partiallyrhyd'rolized aluminum nitrate and alcohol solution. shields the last several turns of wire 15 and the ends 19 so that no coating is deposited thereon.v
  • the uncoated portions of the wire are utilized for a welding connection during ultimate assembly in an electron'tube.
  • anode 55 is also disposed in bath 53, and positive and negative potentials are applied to anode 55 and electrode 51 respec-. tively to electrophoretically ooatwire 15 in a manner well understood in the art. spacing between the spiral turns and coil wraps, the insulating coating is uniformly deposited overv the desired area.
  • Wire is subsequently fired between flat plates of the type shown in FIG. 8.
  • a'wet hydrogen atmosphere may be used during this operation. Firing of the wire assures flatness of the coil, it removes any distortion in the reverse coil wraps, and it sinters the insulating coating 17 to produce the, reverse coil wound spiral heater 13, shown in FIG. 11.
  • a process for forminga spiral reverse coil wound flatheater adapted'for use in anelectro-n' discharge device comprising the steps of winding a spiral of heater'wire upon amandrel, holding the mandrel at a position along an axis intermediate the ends thereof, forming a substantially fiat reverse wound mandrelcoil byrotating said mandrel in a plane about said axis withthe ends thereof rotatively arrested-and-guided for frictionally inhibited movement'substantially'in said plane'toward the mandrel coil during rotation, heating the coiledmandrel arid supportedwire spiral in a reducing atmosphere between flat plates'to anneal the coiled spiral, removing the mandrel from the reverse coiled spiral of wireby selectively etching away'the mandrel, and electrophoretically coating the wire with an 7 electrical insulating material.
  • A'process for forming a-s pir'al reverse coil wound flat-heater adapted for use inan electron discharge device comprising the steps of winding heater wire upon a deformablemandrel under tension to provide a permanently elongated spiral of wire upon the mandrel; holding the mandrel at a position along an a-Xisintermediatethe ends plane about said axis-with the.” ends thereof rotatively arrested and giidedforfr'ictionally inhibited movement substantially in said plane toward the mandrel coil during rotation to' provide substantially tight wrapping of said Dueto the uniformity of tially'uniformlyspaced wraps; heating the coiled mandrel and supported wire spiral in areducing atmosphere between flat pl'at'es'to anneal the coiled'spiral; removing the *ma-ndr'el from the reverse coiled spiral of wire by selectively etching away the -mandrel;,-and coating the wire with an electrically

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Solid Thermionic Cathode (AREA)
  • Electrodes For Cathode-Ray Tubes (AREA)
  • Powder Metallurgy (AREA)
  • Resistance Heating (AREA)
  • Discharge Lamp (AREA)
US14471A 1960-03-11 1960-03-11 Electrical heaters Expired - Lifetime US3160946A (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
NL262042D NL262042A (xx) 1960-03-11
US3097419D US3097419A (en) 1960-03-11 dickson
US14471A US3160946A (en) 1960-03-11 1960-03-11 Electrical heaters
US14470A US3092748A (en) 1960-03-11 1960-03-11 Indirectly heated cathode
GB6534/61A GB908096A (en) 1960-03-11 1961-02-22 Heater cathode assembly and support therefor
DES72903A DE1186559B (de) 1960-03-11 1961-03-09 Kathode fuer Elektronenroehren und Verfahren zu ihrer Herstellung
FR855255A FR1287645A (fr) 1960-03-11 1961-03-10 Ensembles élément de chauffage-cathode et leurs supports
US287401A US3277685A (en) 1960-03-11 1963-06-12 Electrical heaters

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US1447260A 1960-03-11 1960-03-11
US14471A US3160946A (en) 1960-03-11 1960-03-11 Electrical heaters
US14470A US3092748A (en) 1960-03-11 1960-03-11 Indirectly heated cathode
US287401A US3277685A (en) 1960-03-11 1963-06-12 Electrical heaters

Publications (1)

Publication Number Publication Date
US3160946A true US3160946A (en) 1964-12-15

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ID=27486394

Family Applications (4)

Application Number Title Priority Date Filing Date
US3097419D Expired - Lifetime US3097419A (en) 1960-03-11 dickson
US14470A Expired - Lifetime US3092748A (en) 1960-03-11 1960-03-11 Indirectly heated cathode
US14471A Expired - Lifetime US3160946A (en) 1960-03-11 1960-03-11 Electrical heaters
US287401A Expired - Lifetime US3277685A (en) 1960-03-11 1963-06-12 Electrical heaters

Family Applications Before (2)

Application Number Title Priority Date Filing Date
US3097419D Expired - Lifetime US3097419A (en) 1960-03-11 dickson
US14470A Expired - Lifetime US3092748A (en) 1960-03-11 1960-03-11 Indirectly heated cathode

Family Applications After (1)

Application Number Title Priority Date Filing Date
US287401A Expired - Lifetime US3277685A (en) 1960-03-11 1963-06-12 Electrical heaters

Country Status (5)

Country Link
US (4) US3092748A (xx)
DE (1) DE1186559B (xx)
FR (1) FR1287645A (xx)
GB (1) GB908096A (xx)
NL (1) NL262042A (xx)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130192616A1 (en) * 2012-01-31 2013-08-01 Altria Client Services Inc. Electronic cigarette and method

Families Citing this family (6)

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US3762014A (en) * 1966-05-23 1973-10-02 Mallory & Co Inc P R Apparatus for making capacitors
US3444416A (en) * 1966-09-10 1969-05-13 Sony Corp Electron emitting device and method of assembling the same
US3465195A (en) * 1967-03-10 1969-09-02 Funkwerk Erfurt Veb K Shock and vibration-resistant arrangement for cathodes of small heating power
GB1237638A (en) * 1968-04-13 1971-06-30 Sony Corp Electron gun device
JPS6023455B2 (ja) * 1978-10-17 1985-06-07 株式会社東芝 直熱形陰極構体
KR920008501Y1 (ko) * 1990-11-27 1992-11-30 삼성전관 주식회사 초소형 음극선관용 직열형 음극구조체

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US817386A (en) * 1905-01-11 1906-04-10 Charles E Pickrell Metal-bending appliance.
US2287460A (en) * 1940-11-29 1942-06-23 Rca Corp Insulated heater and method of manufacture
US2516930A (en) * 1944-04-14 1950-08-01 Sperry Corp Filament forming method
US2548592A (en) * 1949-08-26 1951-04-10 Gen Electric Resistance strain gauge and method for making same
US2885334A (en) * 1954-01-01 1959-05-05 Int Standard Electric Corp Thermionic cathode heaters
US2936516A (en) * 1954-05-17 1960-05-17 John A Adair Method of making a dielectric core and resistor

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US2335818A (en) * 1942-09-29 1943-11-30 Rca Corp Cathode assembly
US2385386A (en) * 1943-05-07 1945-09-25 Ohio Carbon Company Method of making resistors
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FR1178741A (fr) * 1956-08-06 1959-05-14 Procédé pour élever la limite d'allongement et augmenter la résistance de produits en acier laminé, notamment des aciers pour béton armé, et dispositif permettantd'appliquer ce procédé
US2888591A (en) * 1956-08-22 1959-05-26 Varian Associates Charged particle emitter apparatus
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US734350A (en) * 1902-11-04 1903-07-21 Charley Merritt Mcfatridge Wire-bender.
US817386A (en) * 1905-01-11 1906-04-10 Charles E Pickrell Metal-bending appliance.
US2287460A (en) * 1940-11-29 1942-06-23 Rca Corp Insulated heater and method of manufacture
US2516930A (en) * 1944-04-14 1950-08-01 Sperry Corp Filament forming method
US2548592A (en) * 1949-08-26 1951-04-10 Gen Electric Resistance strain gauge and method for making same
US2885334A (en) * 1954-01-01 1959-05-05 Int Standard Electric Corp Thermionic cathode heaters
US2936516A (en) * 1954-05-17 1960-05-17 John A Adair Method of making a dielectric core and resistor

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130192616A1 (en) * 2012-01-31 2013-08-01 Altria Client Services Inc. Electronic cigarette and method
US9854839B2 (en) * 2012-01-31 2018-01-02 Altria Client Services Llc Electronic vaping device and method
US10092037B2 (en) 2012-01-31 2018-10-09 Altria Client Services Llc Electronic cigarette
US10098386B2 (en) 2012-01-31 2018-10-16 Altria Client Services Llc Electronic cigarette
US10123566B2 (en) 2012-01-31 2018-11-13 Altria Client Services Llc Electronic cigarette
US10405583B2 (en) 2012-01-31 2019-09-10 Altria Client Services Llc Electronic cigarette
US10780236B2 (en) 2012-01-31 2020-09-22 Altria Client Services Llc Electronic cigarette and method
US10881814B2 (en) 2012-01-31 2021-01-05 Altria Client Services Llc Electronic vaping device
US10980953B2 (en) 2012-01-31 2021-04-20 Altria Client Services Llc Electronic cigarette
US11478593B2 (en) 2012-01-31 2022-10-25 Altria Client Services Llc Electronic vaping device
US11730901B2 (en) 2012-01-31 2023-08-22 Altria Client Services Llc Electronic cigarette

Also Published As

Publication number Publication date
US3097419A (en) 1963-07-16
FR1287645A (fr) 1962-03-16
NL262042A (xx)
US3277685A (en) 1966-10-11
GB908096A (en) 1962-10-17
DE1186559B (de) 1965-02-04
US3092748A (en) 1963-06-04

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AS Assignment

Owner name: NORTH AMERICAN PHILIPS CONSUMER ELECTRONICS CORP.

Free format text: ASSIGNS ITS ENTIRE RIGHT TITLE AND INTEREST, UNDER SAID PATENTS AND APPLICATIONS, SUBJECT TO CONDITIONS AND LICENSES EXISTING AS OF JANUARY 21, 1981.;ASSIGNOR:GTE PRODUCTS CORPORATION A DE CORP.;REEL/FRAME:003992/0284

Effective date: 19810708

Owner name: NORTH AMERICAN PHILIPS CONSUMER ELECTRONICS CORP.,

Free format text: ASSIGNS ITS ENTIRE RIGHT TITLE AND INTEREST, UNDER SAID PATENTS AND APPLICATIONS, SUBJECT TO CONDITIONS AND LICENSES EXISTING AS OF JANUARY 21, 1981.;ASSIGNOR:GTE PRODUCTS CORPORATION A DE CORP.;REEL/FRAME:003992/0284

Effective date: 19810708