Patent · US Expired

Robust lamp filament

US6465939B1 · kind B1 · utility

3Cited by
6References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 2, 1999
Grant dateOct 15, 2002
Priority date
Expiry dateDec 2, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J1/18
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A robust coiled filament electrode for a fluorescent lamp used in high vibration environments. A cylindrical mandrel is placed within coils in each end of a coiled filament electrode. The mandrel and the coiled filament electrode are held by a mounting post. The mounting post is bent over and crimped, holding the mandrel and coiled filament electrode. The mandrel extends inward between the two mounting posts, providing support for the coiled filament electrodes. The coiled filament electrode may be made by method or process of chemically dissolving selected portions of a mandrel. Lamp life is extended, as well as the variance between lamp life is substantially reduced. The present invention is particularly applicable to applications in avionics.

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