The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 19, 1991
Filed:
Apr. 14, 1989
Clemens Barthelmes, Berlin, DE;
Axel Bunk, Berlin, DE;
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.