DE1223956B - Method for manufacturing a heater for an indirectly heated cathode of an electron tube - Google Patents
Method for manufacturing a heater for an indirectly heated cathode of an electron tubeInfo
- Publication number
- DE1223956B DE1223956B DEF44917A DEF0044917A DE1223956B DE 1223956 B DE1223956 B DE 1223956B DE F44917 A DEF44917 A DE F44917A DE F0044917 A DEF0044917 A DE F0044917A DE 1223956 B DE1223956 B DE 1223956B
- Authority
- DE
- Germany
- Prior art keywords
- layer
- titanium
- oxide
- aluminum oxide
- 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.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims description 6
- 238000004519 manufacturing process Methods 0.000 title claims description 5
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 claims description 13
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims description 10
- 239000010936 titanium Substances 0.000 claims description 10
- 238000010438 heat treatment Methods 0.000 claims description 8
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 4
- 229910052719 titanium Inorganic materials 0.000 claims description 4
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 3
- 239000004408 titanium dioxide Substances 0.000 claims description 3
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 claims description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims 2
- 230000002349 favourable effect Effects 0.000 claims 2
- 239000001301 oxygen Substances 0.000 claims 2
- 229910052760 oxygen Inorganic materials 0.000 claims 2
- 239000000725 suspension Substances 0.000 claims 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims 1
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims 1
- 229910010413 TiO 2 Inorganic materials 0.000 claims 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims 1
- 239000011230 binding agent Substances 0.000 claims 1
- 230000015572 biosynthetic process Effects 0.000 claims 1
- 238000000354 decomposition reaction Methods 0.000 claims 1
- 238000007598 dipping method Methods 0.000 claims 1
- 230000009189 diving Effects 0.000 claims 1
- 238000001035 drying Methods 0.000 claims 1
- 238000010304 firing Methods 0.000 claims 1
- 239000001257 hydrogen Substances 0.000 claims 1
- 229910052739 hydrogen Inorganic materials 0.000 claims 1
- BAQNULZQXCKSQW-UHFFFAOYSA-N oxygen(2-);titanium(4+) Chemical compound [O-2].[O-2].[O-2].[O-2].[Ti+4].[Ti+4] BAQNULZQXCKSQW-UHFFFAOYSA-N 0.000 claims 1
- 230000005855 radiation Effects 0.000 claims 1
- 238000005507 spraying Methods 0.000 claims 1
- 238000005979 thermal decomposition reaction Methods 0.000 claims 1
- 230000007704 transition Effects 0.000 claims 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims 1
- 239000010410 layer Substances 0.000 description 18
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 3
- 229910000428 cobalt oxide Inorganic materials 0.000 description 3
- IVMYJDGYRUAWML-UHFFFAOYSA-N cobalt(ii) oxide Chemical compound [Co]=O IVMYJDGYRUAWML-UHFFFAOYSA-N 0.000 description 3
- 239000010937 tungsten Substances 0.000 description 3
- 229910001930 tungsten oxide Inorganic materials 0.000 description 3
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 229910017052 cobalt Inorganic materials 0.000 description 2
- 239000010941 cobalt Substances 0.000 description 2
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- QGLKJKCYBOYXKC-UHFFFAOYSA-N nonaoxidotritungsten Chemical compound O=[W]1(=O)O[W](=O)(=O)O[W](=O)(=O)O1 QGLKJKCYBOYXKC-UHFFFAOYSA-N 0.000 description 2
- 238000013021 overheating Methods 0.000 description 2
- 229910052721 tungsten Inorganic materials 0.000 description 2
- 229910052720 vanadium Inorganic materials 0.000 description 2
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 description 2
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- UOUJSJZBMCDAEU-UHFFFAOYSA-N chromium(3+);oxygen(2-) Chemical class [O-2].[O-2].[O-2].[Cr+3].[Cr+3] UOUJSJZBMCDAEU-UHFFFAOYSA-N 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000004040 coloring Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 230000017525 heat dissipation Effects 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- OOAWCECZEHPMBX-UHFFFAOYSA-N oxygen(2-);uranium(4+) Chemical compound [O-2].[O-2].[U+4] OOAWCECZEHPMBX-UHFFFAOYSA-N 0.000 description 1
- 229910052703 rhodium Inorganic materials 0.000 description 1
- 239000010948 rhodium Substances 0.000 description 1
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 description 1
- 229910052566 spinel group Inorganic materials 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- 229910052715 tantalum Inorganic materials 0.000 description 1
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- FCTBKIHDJGHPPO-UHFFFAOYSA-N uranium dioxide Inorganic materials O=[U]=O FCTBKIHDJGHPPO-UHFFFAOYSA-N 0.000 description 1
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
- H01J9/08—Manufacture of heaters for indirectly-heated cathodes
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
- H01B3/02—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of inorganic substances
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B3/00—Ohmic-resistance heating
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Solid Thermionic Cathode (AREA)
Description
DEUTSCHESGERMAN
PATENTAMTPATENT OFFICE
AUSLEGESCHRIFTEDITORIAL
Int. Cl.:Int. Cl .:
HOIjHOIj
Nummer: 1223 956Number: 1223 956
Aktenzeichen: F 44917 VIII c/21 gFile number: F 44917 VIII c / 21 g
Anmeldetag: 9. Januar 1965Filing date: January 9, 1965
Auslegetag: 1. September 1966Opening day: September 1, 1966
Die Erfindung befaßt sich mit einem Verfahren zum Überziehen eines Heizkörpers für thermische Elektronenquellen, insbesondere eines Heizfadens für eine indirekt geheizte Kathode, mit einer schwarzstrahlenden Isolierschicht. The invention relates to a method of covering a heating element for thermal Electron sources, in particular a filament for an indirectly heated cathode, with a black-radiating insulating layer.
Die Vorteile einer schwarzstrahlenden Isolierschicht bestehen unter anderem im folgenden: Während des Betriebes kann eine kleinere Heiztemperatur zur Erhitzung der Kathode auf die vorgeschriebene Emissionstemperatur verwendet werden, so daß weniger Heizleistung benötigt wird. Ferner wird auch die Überheizung des Heizdrahtes beim Einschalten, die für die Lebensdauer bestimmend ist, durch die kleinere Heizleistung verringert. Damit verringert sich die Zahl der Heizfadenbrüche nach längerer Betriebsdauer. Auch werden die Ausfälle durch lokale Uberheizungen des Isolators und dadurch bedingte Durchschläge verringert.The advantages of a black-emitting insulating layer include the following: During during operation, a lower heating temperature can be used to heat the cathode to the prescribed level Emission temperature can be used, so that less heating power is required. Furthermore, will also the overheating of the heating wire when switching on, which is decisive for the service life, by the lower heating power reduced. This reduces the number of broken filaments after a long period of operation. The failures are also caused by local overheating of the insulator and the breakdowns caused by it decreased.
Man hat allgemein als Isolierschicht Aluminiumoxyd verwendet, welches eine hohe mechanische und elektrische Festigkeit und Temperaturbeständigkeit aufweist. Es ist auch bekannt, das Aluminiumoxyd zu färben, um die Wärmeabstrahlung zu verbessern. Zu diesem Zweck wurden dem Aluminiumoxyd geringe Mengen färbender Stoffe, z.B. Chromoxyde, oder Oxyde anderer Metalle, z. B. Titan, Vanadium, Kobalt oder Eisen, zugesetzt. Bei diesen Verfahren wird die Fähigkeit des Aluminiumoxyds zur Bildung von farbigen Spinellen ausgenutzt. Die Lösbarkeit der Zusätze in Al2O3 geht jedoch nicht so weit, daß ein schwarzer Körper gebildet wird.Aluminum oxide, which has high mechanical and electrical strength and temperature resistance, has generally been used as the insulating layer. It is also known to color the aluminum oxide in order to improve the heat dissipation. For this purpose, small amounts of coloring substances, e.g. chromium oxides, or oxides of other metals, e.g. B. titanium, vanadium, cobalt or iron added. In this process, the ability of aluminum oxide to form colored spinels is used. However, the solubility of the additives in Al 2 O 3 does not go so far that a black body is formed.
Auch ist es bekannt, der Isolierschicht aus Al2O3 mindestens zwei ein schwarzes Gemisch bildende Oxyde, der Elemente Titan, Vanadium, Chrom, Mangan, Eisen, Kobalt, Nickel, Molybdän, Rhodium, Wolfram und Tantal in Mengen von höchstens 3e/o zuzusetzen. Da das Aluminiumoxyd ein weißer Strahler ist, können durch diese Zusätze bestenfalls hellgraue Schichten erzielt werden, die keine erhebliche Herabsetzung der Temperatur des Heizers ergeben.It is also known, the insulating layer of Al 2 O 3 at least two black mixture forming oxides of the elements titanium, vanadium, chromium, manganese, iron, cobalt, nickel, molybdenum, rhodium, tungsten, and tantalum in amounts of at most 3 s / o add. Since the aluminum oxide is a white radiator, these additives can at best result in light gray layers that do not result in a significant reduction in the temperature of the heater.
Man hat zur Vermeidung dieses Nachteiles angegeben, den Überzug des Heizdrahtes aus einer hochisolierenden Zwischenschicht und einer die Wärme gut abstrahlenden Außenschicht aus einem dunkel aussehenden Stoff, vorzugsweise aus einem Gemisch aus Al2O3 und metallischem Wolfram, auszubilden. Ferner ist Urandioxyd empfohlen worden. Auch ist vorgeschlagen worden, Kobaltoxyd als Dunkelschicht zu verwenden.In order to avoid this disadvantage, it has been specified to form the coating of the heating wire from a highly insulating intermediate layer and an outer layer which radiates heat well from a dark-looking material, preferably from a mixture of Al 2 O 3 and metallic tungsten. Uranium dioxide has also been recommended. It has also been proposed to use cobalt oxide as a dark layer.
Obwohl die Wärmeübertragung auf die Kathode durch die Verwendung der genannten Stoffe alsAlthough the heat transfer to the cathode through the use of the substances mentioned as
Verfahren zum Herstellen eines Heizers für eine
indirekt geheizte Kathode einer ElektronenröhreMethod of manufacturing a heater for a
indirectly heated cathode of an electron tube
Anmelder:
Fernseh G. m. b. H.,
Darmstadt, Am Alten Bahnhof 6Applicant:
TV G. mb H.,
Darmstadt, Am Alten Bahnhof 6
Als Erfinder benannt:Named as inventor:
Dr. Heinrich Jarczyk, ReinheimDr. Heinrich Jarczyk, Reinheim
Außenschicht wesentlich verbessert wurde, konnte die des idealen schwarzen Strahlers nicht erreicht und nur eine Temperaturherabsetzung um maximal 200° C erzielt werden. Dies hängt zum Teil damit zusammen, daß die für die Außenschicht verwendeten Stoffe nicht hinreichend dunkel (schwarz) sind. Ferner ist es bekannt, den Heizfaden zunächst mit einer gesinterten Schicht aus reinem Aluminiumoxyd und einer weiteren Schicht aus Aluminiumoxyd undThe outer layer was significantly improved, could not match that of the ideal black body and only a temperature reduction of a maximum of 200 ° C can be achieved. This is partly due to it together that the fabrics used for the outer layer are not sufficiently dark (black). It is also known to first coat the filament with a sintered layer of pure aluminum oxide and another layer of aluminum oxide and
a5 Wolframoxyd zu überziehen und diese Schicht zu reduzieren, so daß eine dunkle Oberflächenschicht erzielt wird; vorzugsweise besteht diese 'schwarze Schicht aus 10 Vo Aluminiumoxyd und 20% Wolframoxyd. Auch ist vorgeschlagen worden, das reine Aluminiumoxyd mit einer Schicht von Kobaltoxyd zu überziehen.a5 tungsten oxide to coat and this layer too reduce so that a dark surface layer is obtained; preferably this' black one Layer of 10 Vo aluminum oxide and 20% tungsten oxide. It has also been suggested that to coat pure aluminum oxide with a layer of cobalt oxide.
Bei den Verfahren, bei denen Wolfram- oder Kobaltoxyd oberflächlich aufgebracht werden, besteht die Möglichkeit, daß die Reduktion zu weit geht und stellenweise Metallbrücken erzeugt werden, die zu Überschlägen Anlaß geben können.In the case of processes in which tungsten or cobalt oxide is applied to the surface, there is the possibility that the reduction goes too far and metal bridges are created in places, which can give rise to flashovers.
In einer Veröffentlichung wurde auch als schwarzer Stoff für die Außenschicht Ti2O3 erwähnt, jedoch als unbrauchbar verworfen, da sich dieser Stoff in das weiße Titandioxyd umwandeln soll. In a publication, Ti 2 O 3 was also mentioned as a black substance for the outer layer, but discarded as unusable, since this substance is supposed to be converted into white titanium dioxide.
Bei den Untersuchungen der Anmelderin hat sich jedoch ergeben, daß bei Anwendung eines speziellen,
neuen Herstellungsverfahrens das Titanoxyd Ti2O3
vorzüglich als Schwärzungsschicht geeignet ist, eine Herabsetzung der Heizertemperatur um 300° C ermöglicht
und auch hinreichend beständig ist. Dauerversuche zeigten bis 700 Stunden kein Ansteigen der
Heizertemperatur.
Das neue Verfahren zum Herstellen eines Heizers für eine indirekt geheizte Kathode einer Elektronenröhre,
bei dem der Heizer mit einer gesinterten Schicht aus reinem Aluminiumoxyd und mit einerThe applicant's investigations have shown, however, that when using a special, new production process, the titanium oxide Ti 2 O 3 is ideally suited as a blackening layer, enables the heater temperature to be reduced by 300 ° C. and is also sufficiently stable. Endurance tests showed no increase in heater temperature up to 700 hours.
The new method of manufacturing a heater for an indirectly heated cathode of an electron tube, in which the heater with a sintered layer of pure aluminum oxide and with a
609 658/316609 658/316
Claims (1)
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEF44917A DE1223956B (en) | 1965-01-09 | 1965-01-09 | Method for manufacturing a heater for an indirectly heated cathode of an electron tube |
| GB87566A GB1078530A (en) | 1965-01-09 | 1966-01-07 | Improvements in or relating to the manufacture of heater elements for indirectly heated thermionic cathodes |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEF44917A DE1223956B (en) | 1965-01-09 | 1965-01-09 | Method for manufacturing a heater for an indirectly heated cathode of an electron tube |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| DE1223956B true DE1223956B (en) | 1966-09-01 |
Family
ID=7100261
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DEF44917A Pending DE1223956B (en) | 1965-01-09 | 1965-01-09 | Method for manufacturing a heater for an indirectly heated cathode of an electron tube |
Country Status (2)
| Country | Link |
|---|---|
| DE (1) | DE1223956B (en) |
| GB (1) | GB1078530A (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1126520B (en) * | 1958-04-29 | 1962-03-29 | Rca Corp | Electrically insulating cover for a heating wire of an indirectly heated cathode of an electron tube and process for its production |
-
1965
- 1965-01-09 DE DEF44917A patent/DE1223956B/en active Pending
-
1966
- 1966-01-07 GB GB87566A patent/GB1078530A/en not_active Expired
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1126520B (en) * | 1958-04-29 | 1962-03-29 | Rca Corp | Electrically insulating cover for a heating wire of an indirectly heated cathode of an electron tube and process for its production |
Also Published As
| Publication number | Publication date |
|---|---|
| GB1078530A (en) | 1967-08-09 |
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