Spark plug for internal combustion engines having an alloy layer between the electrodes and tip ends
USRE35012E · kind E · reissue
Assignee
Inventors
Key dates
| Filing date | Jun 9, 1993 |
| Grant date | Aug 8, 1995 |
| Priority date | — |
| Expiry date | Jun 9, 2013 |
Classification
- Technology area (CPC —)General
Abstract
A spark plug for an internal combustion engine including a center electrode, an earth electrode, a metal tip joined by welding to an ignition section of at least one of the center electrode and the earth electrode, and an alloy layer located at a welding portion between the metal tip and the at least one electrode. The metal tip is formed of material highly resistant to heat and wear which is distinct in the coefficient of thermal expansion from the material of the electrodes. The alloy layer is formed to have a thickness of at least about 10.mu., so as to avoid the rupture of the metal tip along the surface thereof adjacent to the welding portion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.