US3911312A - Oxide cathode for an electric discharge tube - Google Patents
Oxide cathode for an electric discharge tube Download PDFInfo
- Publication number
- US3911312A US3911312A US474587A US47458774A US3911312A US 3911312 A US3911312 A US 3911312A US 474587 A US474587 A US 474587A US 47458774 A US47458774 A US 47458774A US 3911312 A US3911312 A US 3911312A
- Authority
- US
- United States
- Prior art keywords
- support
- nickel
- layer
- discharge tube
- electric discharge
- 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
Links
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 8
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 8
- 238000000034 method Methods 0.000 claims abstract description 7
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 6
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 22
- 229910052759 nickel Inorganic materials 0.000 claims description 10
- 239000010936 titanium Substances 0.000 claims description 7
- 239000012535 impurity Substances 0.000 claims description 5
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims description 4
- 229910052788 barium Inorganic materials 0.000 claims description 4
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 claims description 4
- 229910052791 calcium Inorganic materials 0.000 claims description 4
- 239000011575 calcium Substances 0.000 claims description 4
- 229910052799 carbon Inorganic materials 0.000 claims description 4
- 229910052749 magnesium Inorganic materials 0.000 claims description 4
- 239000011777 magnesium Substances 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 4
- 229910052712 strontium Inorganic materials 0.000 claims description 4
- CIOAGBVUUVVLOB-UHFFFAOYSA-N strontium atom Chemical compound [Sr] CIOAGBVUUVVLOB-UHFFFAOYSA-N 0.000 claims description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 3
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 3
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 3
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 3
- 239000011651 chromium Substances 0.000 claims description 3
- 229910052804 chromium Inorganic materials 0.000 claims description 3
- 239000010703 silicon Substances 0.000 claims description 3
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 abstract description 7
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 3
- QVQLCTNNEUAWMS-UHFFFAOYSA-N barium oxide Chemical compound [Ba]=O QVQLCTNNEUAWMS-UHFFFAOYSA-N 0.000 description 2
- 230000001627 detrimental effect Effects 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- IATRAKWUXMZMIY-UHFFFAOYSA-N strontium oxide Chemical compound [O-2].[Sr+2] IATRAKWUXMZMIY-UHFFFAOYSA-N 0.000 description 2
- 101100264195 Caenorhabditis elegans app-1 gene Proteins 0.000 description 1
- 229910000990 Ni alloy Inorganic materials 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
Images
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
- H01J1/26—Supports for the emissive material
Definitions
- ABSTRACT An oxide cathode having an oxide layer obtained from triple carbonate and a support obtained according to the powder-metallurgical method having a content of Si, Al and Ti lower than 0.005, percent by weight.
- the invention relates to an oxide cathode for an electric discharge tube and in particular to such a cathode whose emissive layer consists of a mixture of oxides of barium, strontium and calcium and in which a good adhesion of the emissive oxide layer to a nickel cathode support is obtained.
- a cathode having such an oxide layer is known from French Pat. Specification No. 1,107,589.
- the oxides of said layer are obtained from the carbonates.
- a mixture of the carbonates of the said metal is termed triple carbonate and comprises the said carbonates of barium, strontium and calcium, for example, in the weight ratio 7, 6, l.
- a drawback of such oxide layers formed from triple carbonate is that the adhesion to a nickel cathode support leaves to be desired.
- the support consists of nickel obtained according to the known powder-metallurgical method which comprises reductors such as magnesium and/or carbon, but in which the silicon, aluminum and titanium content is lower than 0.005 percent by weight.
- reductors such as magnesium and/or carbon
- Other impurities such as chromium which may form an intermediate layer with the emissive layer should also be below said limit.
- FIGURE is a longitudinal sectional view through a cathode according to the invention.
- Reference numeral 1 in the FIGURE denotes a cathode support consisting of nickel which has been obtained from carbonyl nickel to which a small quantity of reductors such as Mg and C has been added according to the powder metallurgical method. Said addition may be effected as is described in French Pat. Specification No. 1,152,810 by adding to the carbonyl nickel a given quantity of an alloy of nickel with the said reductors.
- the quantity of reductors in the ultimate alloy which serves for manufacturing the support is, for example, from 0.1 to 0.01 percent by weight for each re-.
- a heating member 3 is present in the support 1.
- cathode Although only one embodiment of a cathode according to the invention is shown, the invention is also of importance for so-called pot cathodes in which the emissive oxide layer is present on a closed end face of a cylindrical support.
- Such cathodes are suitable in particular for electron ray tubes, travelling wave tubes, klystrons and other tubes operating with beams of electron current and having a comparatively strongly loaded cathode (cathode current more than 1 amp. per cm of cathode area).
- the cylindrical cathodes according to the drawing are very suitable for amplifier tubes which supply a comparatively large power, for example, ballast tubes and line output tubes for television apparatus.
- An oxide cathode for an electric discharge tube comprising a nickel support, a layer of emissive oxides provided on said support, said layer including a mixture of oxides of barium, strontium and calcium, said support being of nickel obtained according to the powdermetallurgical method and including reductors selected from the group consisting of magnesium and carbon, said nickel having the content of impurity selected from the group consisting of silicon, aluminum, titanium and chromium, lower than 0.005 per cent by weight to increase adhesion of said layer to said support.
Abstract
An oxide cathode having an oxide layer obtained from triple carbonate and a support obtained according to the powdermetallurgical method having a content of Si, Al and Ti lower than 0.005 percent by weight.
Description
United States Patent Coenen et a].
Oct. 7, 1975 OXIDE CATI-IODE FOR AN ELECTRIC DISCHARGE TUBE Inventors: Renier Gertruda I-Iubertus Coenen,
Eindhoven; Karel Martin Hubert Leummens, Nijmegen; Erland Charles Justus Swaving, Eindhoven, all of Netherlands Assignee: U.S. Philips Corporation, New
York, N.Y.
Filed: May 30, 1974 App1. No.: 474,587
Foreign Application Priority Data June 6, 1973 Netherlands 7307855 11.5. C1 313/346 R; 313/311; 313/337 1111. 0. HOIJ 1 14; I-lOlJ 19/06 Field of Search 313/346, 352, 354, 311
Primary Examiner-Saxfield Chatmon, Jr. Attorney, Agent, or Firm-Frank R. Trifari; George B. Berka [57] ABSTRACT An oxide cathode having an oxide layer obtained from triple carbonate and a support obtained according to the powder-metallurgical method having a content of Si, Al and Ti lower than 0.005, percent by weight.
1 Claim, 1 Drawing Figure US. Patent 0ct. 7 ,1975 v 3,911,312
OXIDE CATIIODE FOR AN ELECTRIC DISCHARGE TUBE The invention relates to an oxide cathode for an electric discharge tube and in particular to such a cathode whose emissive layer consists of a mixture of oxides of barium, strontium and calcium and in which a good adhesion of the emissive oxide layer to a nickel cathode support is obtained.
A cathode having such an oxide layer is known from French Pat. Specification No. 1,107,589. The oxides of said layer are obtained from the carbonates. A mixture of the carbonates of the said metal is termed triple carbonate and comprises the said carbonates of barium, strontium and calcium, for example, in the weight ratio 7, 6, l. A drawback of such oxide layers formed from triple carbonate is that the adhesion to a nickel cathode support leaves to be desired.
A very good adhesion of an emissive oxide layer obtained in a triple carbonate can be obtained, if, according to the invention, the support consists of nickel obtained according to the known powder-metallurgical method which comprises reductors such as magnesium and/or carbon, but in which the silicon, aluminum and titanium content is lower than 0.005 percent by weight. Other impurities, such as chromium which may form an intermediate layer with the emissive layer should also be below said limit.
An oxide cathode in which a support is manufactured from nickel prepared according to the powder metallurgical method is known from French Pat. Specification No. 1,152,810. In this specification the Si content was maintained low with a view to the formation of a poorly electrical conducting layer between the oxide layer and the support, but nothing was stated about the Al and Ti contents. In connection with the adhesion said impurities were of little significance since the oxide layer contained barium oxide and strontium oxide only. Such a layer containing only two oxides presents far fewer difficulties in connection with the adhesion.
It has now been found that the presence of Al and Ti in the support is very detrimental to the adhesion of oxide layers obtained from triple carbonate, in particular when the cathodes are to supply a comparatively large current.
The invention will be described in greater detail with reference to the drawing, the sole FIGURE of which is a longitudinal sectional view through a cathode according to the invention.
Reference numeral 1 in the FIGURE denotes a cathode support consisting of nickel which has been obtained from carbonyl nickel to which a small quantity of reductors such as Mg and C has been added according to the powder metallurgical method. Said addition may be effected as is described in French Pat. Specification No. 1,152,810 by adding to the carbonyl nickel a given quantity of an alloy of nickel with the said reductors. The quantity of reductors in the ultimate alloy which serves for manufacturing the support is, for example, from 0.1 to 0.01 percent by weight for each re-.
ductor. It is ensured that the quantity of detrimental reductors Si, Al and Ti present as an impurity is less than 0.005 percent by weight. It has been found that an oxide layer formed from triple carbonate very readily adheres to such a support.
A heating member 3 is present in the support 1.
Although only one embodiment of a cathode according to the invention is shown, the invention is also of importance for so-called pot cathodes in which the emissive oxide layer is present on a closed end face of a cylindrical support. Such cathodes are suitable in particular for electron ray tubes, travelling wave tubes, klystrons and other tubes operating with beams of electron current and having a comparatively strongly loaded cathode (cathode current more than 1 amp. per cm of cathode area).
The cylindrical cathodes according to the drawing are very suitable for amplifier tubes which supply a comparatively large power, for example, ballast tubes and line output tubes for television apparatus.
What is claimed is:
1. An oxide cathode for an electric discharge tube, comprising a nickel support, a layer of emissive oxides provided on said support, said layer including a mixture of oxides of barium, strontium and calcium, said support being of nickel obtained according to the powdermetallurgical method and including reductors selected from the group consisting of magnesium and carbon, said nickel having the content of impurity selected from the group consisting of silicon, aluminum, titanium and chromium, lower than 0.005 per cent by weight to increase adhesion of said layer to said support.
Claims (1)
1. AN OXIDE CATHODE FOR AN ELECTRIC DISCHARGE TUBE, COMPRISING A NICKEL SUPPORT, A LAYER OF EMISSIVE OXIDES PROVIDED ON SAID SUPPORT, SAID LAYER INCLUDING A MIXTURE OF OXIDES OF BARIUM, STRONTIUM AND CALCIUM, SAID SUPPORT BEING OF NICKEL OBTAINED ACCORDING TO THE POWDER-METALLURGICAL METHOD AND INCLUDING REDUCTORS SELECTED FROM THE GROUP CONSISTING OF MAGNESIUM AND CARBON, SAID NICKEL HAVING THE CONTENT OF IMPURITY SELECTED FROM THE GROUP CONSISTING OF SILICON, ALUMINUM, TITANIUM AND CHROMIUM, LOWER THAN 0.005 PER CENT BY WEIGHT TO INCREASE ADHESION OF SAID LAYER TO SAID SUPPORT.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL7307855.A NL158647B (en) | 1973-06-06 | 1973-06-06 | OXYD CATHOD FOR AN ELECTRIC DISCHARGE TUBE. |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US05687217 Continuation | 1976-05-17 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3911312A true US3911312A (en) | 1975-10-07 |
Family
ID=19819020
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US474587A Expired - Lifetime US3911312A (en) | 1973-06-06 | 1974-05-30 | Oxide cathode for an electric discharge tube |
Country Status (9)
| Country | Link |
|---|---|
| US (1) | US3911312A (en) |
| JP (1) | JPS5621212B2 (en) |
| CA (1) | CA1008914A (en) |
| DE (1) | DE2425337C3 (en) |
| ES (1) | ES426956A1 (en) |
| FR (1) | FR2232833B1 (en) |
| GB (1) | GB1470318A (en) |
| IT (1) | IT1014280B (en) |
| NL (1) | NL158647B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1385190A1 (en) * | 2002-07-24 | 2004-01-28 | Thomson Licensing S.A. | Oxide cathode for electron gun with a differentially doped metallic substrate |
| US20060158086A1 (en) * | 2002-07-24 | 2006-07-20 | Jean-Michel Roquais | Oxide cathode for electron gun with a differentially doped metallic substrate |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS51115765A (en) * | 1975-04-03 | 1976-10-12 | Sony Corp | Electron tube cathode apparatus |
| JPS5351798U (en) * | 1976-10-02 | 1978-05-02 |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2179110A (en) * | 1938-08-27 | 1939-11-07 | Rca Corp | Cathode for electron discharge devices |
| US2192491A (en) * | 1939-02-01 | 1940-03-05 | Rca Corp | Cathode for electron discharge devices |
| US3056061A (en) * | 1959-03-06 | 1962-09-25 | Philips Corp | Method of manufacturing nickel supports for oxide cathodes and cathodes provided with such supports |
| US3099577A (en) * | 1960-08-24 | 1963-07-30 | Philips Corp | Method of manufacturing oxide cathodes and cathodes manufactured by such methods |
| US3351486A (en) * | 1966-11-23 | 1967-11-07 | Sylvania Electric Prod | Cathodes |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1107589A (en) * | 1954-06-18 | 1956-01-03 | Csf | Improvements to oxide cathode supports |
| FR1152810A (en) * | 1955-06-29 | 1958-02-26 | Philips Nv | Oxide cathode and process for preparing nickel alloys for their bottom coating |
| GB1076229A (en) * | 1963-10-08 | 1967-07-19 | Sylvania Electric Prod | Cathodes |
-
1973
- 1973-06-06 NL NL7307855.A patent/NL158647B/en not_active IP Right Cessation
-
1974
- 1974-05-25 DE DE2425337A patent/DE2425337C3/en not_active Expired
- 1974-05-29 CA CA201,140A patent/CA1008914A/en not_active Expired
- 1974-05-30 US US474587A patent/US3911312A/en not_active Expired - Lifetime
- 1974-06-03 IT IT68747/74A patent/IT1014280B/en active
- 1974-06-03 JP JP6198274A patent/JPS5621212B2/ja not_active Expired
- 1974-06-03 GB GB2440374A patent/GB1470318A/en not_active Expired
- 1974-06-04 ES ES426956A patent/ES426956A1/en not_active Expired
- 1974-06-06 FR FR7419481A patent/FR2232833B1/fr not_active Expired
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2179110A (en) * | 1938-08-27 | 1939-11-07 | Rca Corp | Cathode for electron discharge devices |
| US2192491A (en) * | 1939-02-01 | 1940-03-05 | Rca Corp | Cathode for electron discharge devices |
| US3056061A (en) * | 1959-03-06 | 1962-09-25 | Philips Corp | Method of manufacturing nickel supports for oxide cathodes and cathodes provided with such supports |
| US3099577A (en) * | 1960-08-24 | 1963-07-30 | Philips Corp | Method of manufacturing oxide cathodes and cathodes manufactured by such methods |
| US3351486A (en) * | 1966-11-23 | 1967-11-07 | Sylvania Electric Prod | Cathodes |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1385190A1 (en) * | 2002-07-24 | 2004-01-28 | Thomson Licensing S.A. | Oxide cathode for electron gun with a differentially doped metallic substrate |
| WO2004012217A1 (en) * | 2002-07-24 | 2004-02-05 | Thomson Licensing S.A. | Oxide cathode for electron gun with a differentially doped metallic substrate. |
| US20060158086A1 (en) * | 2002-07-24 | 2006-07-20 | Jean-Michel Roquais | Oxide cathode for electron gun with a differentially doped metallic substrate |
| US7208864B2 (en) | 2002-07-24 | 2007-04-24 | Thomson Licensing | Oxide cathode for electron gun with a differentially doped metallic substrate |
| CN100437874C (en) * | 2002-07-24 | 2008-11-26 | 汤姆森许可贸易公司 | Oxide cathode for electron gun with a differentially doped metallic substrate |
Also Published As
| Publication number | Publication date |
|---|---|
| DE2425337A1 (en) | 1975-01-02 |
| GB1470318A (en) | 1977-04-14 |
| JPS5621212B2 (en) | 1981-05-18 |
| DE2425337C3 (en) | 1981-06-25 |
| NL158647B (en) | 1978-11-15 |
| FR2232833A1 (en) | 1975-01-03 |
| NL7307855A (en) | 1974-12-10 |
| CA1008914A (en) | 1977-04-19 |
| ES426956A1 (en) | 1976-08-01 |
| FR2232833B1 (en) | 1978-12-29 |
| JPS5023554A (en) | 1975-03-13 |
| AU6971174A (en) | 1975-12-04 |
| IT1014280B (en) | 1977-04-20 |
| DE2425337B2 (en) | 1978-04-27 |
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