Spark plug with ground electrode having mechanically locked precious metal feature
US7190106B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 30, 2005 |
| Grant date | Mar 13, 2007 |
| Priority date | — |
| Expiry date | Dec 30, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01T13/32
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A ground electrode for a spark plug has a through hole located adjacent a firing end of the electrode, with a precious metal firing tip extending through the hole. The firing tip is compressed axially to define a bulging portion extending radially outwardly from its longitudinal axis to mechanically retain the firing tip within the through hole. The firing tip additionally has an enlarged head or otherwise expanded portion at each axial end of the tip to provide a second mechanical interlock of the tip to the ground electrode. The firing tip can then also be welded to further strengthen its connection to the ground electrode. A method of manufacturing the ground electrode and a spark plug containing the ground electrode is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.