Spark plug and producing method therefor
US6768249B1 · kind B1 · utility
6Cited by
3References
16Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 25, 2000 |
| Grant date | Jul 27, 2004 |
| Priority date | — |
| Expiry date | Dec 28, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C2222/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a spark plug, a complex chromate coat 42 that contains a chromium component and a phosphorus component as cationic components, at least 90 wt % of the chromium component being trivalent chromium and the phosphorus component being present in an amount of 1 to 15 wt % as calculated for PO4, is formed on the surface of the galvanized main metal shell 1 of a spark plug. If a silicon component is substituted for the phosphorus component, it may be present in an amount of 5 to 75 wt % as calculated for SiO2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.