http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-537826-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_fb6664456a7258fd59152873346749f9 http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_fbd3cefb4f504c554f2859b7eee1ff4e |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/H01J61-72 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/H01J61-72 |
| filingDate | 1940-01-01-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1941-07-08-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-537826-A |
| titleOfInvention | Improvements in cathodes of electric discharge devices |
| abstract | 537,826. Discharge lamps. GENERAL ELECTRIC CO., Ltd., and PIRANI, M. Jan. 1, 1940, Nos. 40 and 8759. [Class 39 (i)] In the manufacture of the cathode of an electric discharge device, particularly of the low pressure arc discharge type, a compound of a thermionically active metal, stable under exposure to the atmosphere, is mixed with a reducing agent and preferably also a binder, and the mixture is heated within the discharge envelope to a temperature to cause reaction between the reducing agent and compound and produce a cathode which consists of, or is coated with, an electrically conducting material. The compound and reducing agent are chosen so that the latter is not volatile at the reaction temperature. The compound may be the chromate or aluminate of barium, strontium or calcium ; the reducing agent may be silicon, zirconium, tantalum, ferro-titanium or manganese titanium. More volatile reducing agents, such as aluminium, may be used when shields surrounding the electrodes are provided. As binder may be used potassium water-glass, or an organic material such as a solution of ethyl cellulose. A pellet prepared from the mixture is preferably placed within a tungsten helix which serves as the support and heating element for the reaction. In a low pressure arc discharge device, the cathodes are associated with auxiliary electrodes extending side by side throughout most of the space between the electrodes as described in Specification 523,839. These may be sensitized by a solution of barium azide and 1 per cent of caesium azide so as to spread the initial discharge over their length. An example of the discharge device comprises an envelope 400 m.m. long and 20 m.m. in diameter, filled with argon at 10 m.m. pressure mixed with mercury vapour saturated at room temperature with a series impedance adjusted so that the tube carried in full operation, 300 m.A at 80-100 volts between the electrodes, the discharge starts regularly on 200 volts A.C. Specifications 306,281, 309,581, [both in Class 39 (i)], 397,836, 521,818 and U.S.A. Specification 2,002,653 also are referred to. |
| priorityDate | 1940-01-01-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 43.