Spark plug for internal combustion engine and production method thereof
US9825432B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 9, 2016 |
| Grant date | Nov 21, 2017 |
| Priority date | — |
| Expiry date | Sep 9, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01T21/02
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A spark plug for an internal combustion engine is provided which includes a housing, a porcelain insulator, a center electrode, and an annular ground electrode. The housing has a small-diameter portion which has a smaller inner diameter and defines a front end thereof. The ground electrode is secured to a front end surface of the small-diameter portion and forms a spark gap between itself and an outer periphery of the center electrode. The ground electrode is smaller in outer diameter than the front end surface of the small-diameter portion. A annular weld which joints the ground electrode and the small-diameter portion is formed in an annular boundary through which the front end surface of the small-diameter portion and the base end surface of the ground electrode face each other. The annular weld continuously and fully extends in a circumferential direction of the ground electrode.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.