Patent · US Expired

Filament structure and method of making such structure

US4973878A · kind A · utility

0Cited by
7References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 24, 1989
Grant dateNov 27, 1990
Priority date
Expiry dateJul 24, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01K3/06
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A method of making an axial filament structure for a lamp in which the filament is concentric with the axis of the envelope, wherein a hook-like shape (131) is formed in a support member (117) which stretches the filament to its final turns-per-inch ratio.

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