Low-pressure mercury vapor discharge lamp, particularly U-shaped fluorescent lamp, and method of its manufacture

US4481442A · kind A · utility

Assignee

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

Inventors

• Wolfgang Albrecht · Berlin, DE
• Dieter Hofmann · Augsburg, DE
• Lutz Klein · Scheuring, DE
• Ernst Panofski · Augsburg, DE

Key dates

• Filing date: Feb 26, 1982
• Grant date: Nov 6, 1984
• Expiry date: Feb 26, 2002

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01J61/30
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

To reduce the operating temperature of a U-shaped or multiple U-bent fluocent lamp, the respective longitudinal and transverse sectional elements of the U-shaped lamp are so related that the outer generating line M.sub.Q of the individual transverse tube sections (4; 20, 21, 22) is substantially straight; PA1 the diameter D.sub.LQ in the tube bends (5, 6; 23, 24, 25, 26, 27, 28) at the transition between the longitudinal tube sections (2, 3; 16, 17, 18, 19) and the respective transverse tube sections (4; 20, 21, 22) is larger than the diameter D.sub.Q of the individual transverse tube sections in the middle thereof, PA1 and the diameter D.sub.Q of the transverse tube section is at least as large as the diameter D.sub.L of the longitudinal tube sections; PA1 a depression or dent can be formed at the center of the outer surface of the transverse tube section, and the corners of the transverse tube section can include additional heat dissipating material to further reduce the operating temperature.