Patent · US Expired

Spark plug having improved consumption resistance

US5977695A · kind A · utility

36Cited by
10References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 13, 1997
Grant dateNov 2, 1999
Priority date
Expiry dateMay 13, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01T13/39
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

To provide a spark plug having an improved consumption resistance and producible through a simple process, a spark plug comprises a noble metal chip composed of an Ir alloy material and disposed on at least one of the tip of the center electrode and the facing portion of the ground electrode, the Ir alloy material is composed of Ir and a metal having a higher oxidation resistance than Ir and forming solid solution with Ir at all proportions to prevent oxidation evaporation of Ir, and the chip is produced by elongating an ingot of the Ir alloy material through hot forging to a bar having a fine fiber texture to prevent surface cracking during elongation, followed by hot rolling, hot wire drawing and cutting to the chip length.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.