Electrode feedthrough assembly for arc discharge lamp
US4804889A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 18, 1987 |
| Grant date | Feb 14, 1989 |
| Priority date | — |
| Expiry date | Dec 18, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J9/323
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A ceramic arc tube assembly for an arc discharge lamp includes an arc tube having openings for electrode feedthroughs at opposite ends. The feedthroughs each comprise a niobium tube having a tungsten electrode welded to it. A connection wire is welded to the feedthrough at or near the end of the niobium tube, and the feedthrough is subsequently sealed into the arc tube with the connection wire abutting the arc tube. Since the connection wire is prewelded to the feedthrough, the feedthrough can be made as short as practicable without risk of damaging the seal during welding. As a result, feedthrough material cost is substantially reduced. Preferably, the connection wire is used for locating the feedthrough in the arc tube during seal formation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.