High-pressure electric discharge lamp with tight lead-through pin electrode connection and method of its manufacture
US5446341A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 27, 1993 |
| Grant date | Aug 29, 1995 |
| Priority date | — |
| Expiry date | May 27, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/366
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
To provide a tight seal between an essentially solid niobium or tantalum necting pin or rod (10) passing through an opening (7, 28) in an end plug (11) closing off a high-pressure discharge lamp discharge vessel (8), the pin or rod is formed with two axial portions, one of which has externally projecting continuous rings (17), preferably two or three, or an externally projecting thread (26). The rings or thread are press-fitted into the end portion of the bore in the plug, which deforms the edge (20) of the rim, ridge or thread, or shears off the edge portion, ensuring a tight preliminary fit in the bore; sealing glass, which is then melted to fill a capillary space between the pin or rod and the plug, is protected by the preliminary seal against corrosion or attack from the fill within the discharge lamp; if the projection is in form of a thread, glass can penetrate within the threads to further seal and retain the pin or rod. Diffusion-welding of the threads or ridges to the walls of the plug can also be used.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.