Spark plug and method of producing central electrode thereof
US11367999B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 20, 2020 |
| Grant date | Jun 21, 2022 |
| Priority date | — |
| Expiry date | Nov 20, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01T21/02
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A spark plug has a central electrode and a ground electrode. The central electrode has an electrode base material part and a noble metal chip of a cylindrical shape and is welded on the electrode base material part. A spark discharge is generated between the noble metal chip of the central electrode and the ground electrode when supplying a predetermined voltage to the spark plug. An intermediate region is formed on an overall surface between the electrode base material part and the noble metal chip. The intermediate region has a primary measurement part and a secondary measurement part. Components of the noble metal chip in the primary measurement area have a first average ratio of not less than 40 wt %, and components of the noble metal chip in the secondary measurement area have a second average ratio of not more than 80 wt %.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.