Helical wire coil in solenoidal lamp tip-off region wetted by alloy forming an amalgam with mercury
US4262231A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 25, 1978 |
| Grant date | Apr 14, 1981 |
| Priority date | — |
| Expiry date | Oct 25, 1998 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J7/14
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A lead-tin-bismuth alloy is disposed within a solenoidal electric field lamp to control the mercury vapor pressure. In accordance with one embodiment of the present invention, the alloy is placed within the tip-off region of the lamp envelope. The alloy is fixed within the tip-off region by a means of wetting the alloy to a metal wire structure such as a helix or a cylindrical screen. Alternatively, the alloy may be placed on an interior surface of the envelope by first wetting the glass with a layer of indium. Additionally, methods for wetting the lead-tin-bismuth alloy to the metal wire include firing the alloy in contact with the wire in a hydrogen atmosphere at a sufficiently high temperature to wet the alloy to the wire. The present invention permits the control of mercury vapor pressure in solenoidal electric field discharge lamps.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.