Photoflash lamp
US3947225A · kind A · utility
1Cited by
4References
13Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 31, 1975 |
| Grant date | Mar 30, 1976 |
| Priority date | — |
| Expiry date | Mar 31, 1995 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF21K5/02
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A photoflash lamp having an envelope comprised of a lead-containing glass having a low coefficient of thermal expansion and a pair of filament-supporting lead-in wires secured to the glass envelope by means of a graded seal having a lead-free intermediate expansion glass disposed between the envelope and lead-in wires. The lead-in wires are composed of an iron-nickel-cobalt alloy. The intermediate expansion glass may be in the form of a bead having its midportion between the lead-in wires stretched to protrude toward the filament to prevent post-ignition short circuits.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.