Spark plug and process of producing same
US6093071A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 1999 |
| Grant date | Jul 25, 2000 |
| Priority date | — |
| Expiry date | Jun 28, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01T13/39
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A process of producing a spark plug having an improved consumption resistance is provided. The spark plug comprises a noble metal chip composed of an Iridium (Ir) alloy material and includes an insulator enclosing a center electrode and a ground electrode, which has a facing portion facing the tip of the center electrode. The chip may be disposed on the tip of the center electrode, the facing portion of the ground electrode or both. The Ir alloy material consists of Ir and a metal that has a higher oxidation resistance than Ir and forms a solid solution with Ir at all proportions to prevent oxidation evaporation of Ir. In order to prevent surface cracking, the chip is produced by elongating an ingot of the Ir alloy material through hot forging to form a bar having a fine fiber texture. Then, the chip is hot rolled, hot wire drawn and cut to the desired length.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.