Arc discharge lamp containing mechanism for extinguishing arc at end-of-life
US5210461A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 18, 1992 |
| Grant date | May 11, 1993 |
| Priority date | — |
| Expiry date | Feb 18, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/70
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An arc discharge lamp having an end-of-life structure and including a light-transmissive envelope having a tubular-shaped main body and a press seal disposed at each end of the main body. An electrode filament having a pair of ends is located in each end of the envelope. Each electrode filament end is in a contiguous relationship with an inside surface of the lamp envelope. When one of the electrode filaments is depleted of electron-emissive material, increased heating of the electrode filament caused by an increase in cathode fall voltage, produces a localized hot spot on the internal surface of the envelope. This localized heating causes a puncture in the lamp envelope and evacuation of the lamp. The introduction of external atmosphere into the lamp extinguishes the arc discharge and renders the lamp inoperable.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.