Patent · US Expired

High-pressure discharge lamp with corrosion protected electrode leads

US5001395A · kind A · utility

4Cited by

5References

10Claims

0Family size

Assignee

Patent-Treuhand-Gesellschaft fur elektrische Gluhlampen mbH · DE

Inventors

Clemens Barthelmes · Berlin, DE
Axel Bunk · Berlin, DE

Key dates

Filing date	Apr 14, 1989
Grant date	Mar 19, 1991
Priority date	—
Expiry date	Apr 14, 2009

Classification

Technology area (CPC H)Electricity
CPC primaryH01J61/368
WIPO fieldElectrical machinery, apparatus, energy
WIPO sectorElectrical engineering

Abstract

To protect tungsten electrode shafts (2, 3; 15, 16) extending into the a rtz glass discharge chamber (13, 27) of a high-pressure discharge lamp from attack by metal halides included in the fill to improve the color rendition of the discharge, the electrode shafts (2, 3; 15, 16) are tightly surronded by small tubes (11, 12; 25, 26) of electrically insulating material, which is highly temperature resistant, located in part within the press seal (10; 23, 24) and fitted against the ends of sealing foils (6, 7; 19, 20) which face the discharge chamber. The tube elements extend at least about 0.5 mm beyond the inner ends of the press seal (10; 23, 24) into the discharge chamber (13, 27) and are formed of a material which has a thermal coefficient of expansion which is not lower than that of quartz glass and not higher than that of tungsten.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.