Halogen incandescent lamp with filament positioning arrangement

US5686794A · kind A · utility

Assignee

• Patent-Treuhand-Gesellschaft fur elektrische Gluhlampen mbH · DE

Inventors

• Hans-Juergen Streppel · Wipperfürth, DE
• Hans Liermann · Kandern, DE
• Juergen Eder · Cologne, DE

Key dates

• Filing date: Jun 5, 1996
• Grant date: Nov 11, 1997
• Expiry date: Jun 5, 2016

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01K1/28
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

To positively locate a filament (5, 22) in position within a bulb (2) of a halogen incandescent lamp, the walls of the bulb are deformed at selected points along the length of the filament within the bulb to define at least three inwardly projecting dimples which just barely engage, or engage, the filament. Preferably, the filament is formed with a connecting portion (7) in the region of engagement, which connecting portion is either straight, coiled with a very steep pitch, or, if the filament is double-coiled, only single-coiled. The connecting portion (7) may be electrically short-circuited by a core pin (39). If the bulb is single-ended (FIG. 3), a return lead (29) along the wall of the bulb, can be pinched between adjacent walls (45) of adjacent dimples. The dimples, looked at from the outside of the lamp, are essentially funnel-shaped and, in cross section, may be circular, or if space between adjacent dimples is insufficient, may be elliptical.