Lamp filament support construction
US4868451A · kind A · utility
5Cited by
4References
27Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 16, 1988 |
| Grant date | Sep 19, 1989 |
| Priority date | — |
| Expiry date | Dec 16, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49227
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method of constructing a filament support member from a single-piece preformed refractory metal wire having at least one loop protrusion formed in the wire and positioned between the ends of the wire. A section of glass tubing is positioned over and supported by the loop protrusion with a head portion of the loop extending beyond the section of tubing. Heat is applied to melt the section of tubing to form an insulating bead at the base of said loop protrusion. The head portion of the loop protrusion is then trimmed to interrupt electrical continuity in the wire and thus electrically isolate the respective ends of the wire.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.