Ceramic discharge vessel for a high-pressure discharge lamp, having a filling bore sealed with a plug, and method of its manufacture

US5637960A · kind A · utility

Assignees

• Patent-Treuhand-Gesellschaft fur elektrische Gluhlampen mbH · DE
• NGK INSULATORS, LTD. · JP

Inventors

• Stefan Juengst · Zorneding, DE
• Roland Huettinger · Jesenwang, DE
• Jens Clark · Ebersberg, DE
• Osamu Asano · Tokyo, JP
• Kouichiro Maekawa · Ichinomiya, JP

Key dates

• Filing date: Jul 11, 1995
• Grant date: Jun 10, 1997
• Expiry date: Jul 11, 2015

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01J61/827
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

To provide a tight seal for a fill bore in the wall or an end plug of a dharge vessel for high-pressure discharge lamps, a fill bore is provided either through the wall--in the region of the plug--or through a plug, and the fill bore is then closed by a stopper in combination with a melt sealing material, which is so chosen that the sealing material and plug-like member combination provide a minimum of sealing material exposed to the fill in the discharge volume. The fill in the discharge volume of the discharge vessel is ionizable and, for example containing halides, is highly corrosive to the sealing material. The lamp can be made by inserting a stopper into the filling bore, applying, with the stopper in place in the filling bore, sealing material to the outer end of the filling bore, and heating the portion of the discharge vessel to liquefying temperature of the sealing material to liquefy the sealing material and hence close off the fill bore.