Spark plug having horizontal discharge gap
US5502351A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 1994 |
| Grant date | Mar 26, 1996 |
| Priority date | — |
| Expiry date | Apr 8, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01T13/467
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The tip 10 of the center electrode 1 is opposed to the ground electrodes 21 and 22. The tip 10 has flat faces 111 and 121 opposed to the discharge faces of the ground electrodes 211 and 221, and inclined faces 101 and 102 extending from the flat faces to the base 19. The flat faces have noble metal pieces 31 and 32 at positions opposed to the discharge faces. The discharge faces have a spark gap G between itself and the noble metal piece, a minimum gap A between itself and the inclined face, and a minimum gap B between itself and the tip face 41 of the insulator 4. The spark gap G, minimum gap A, and minimum gap B are related such that the distance of A.gtoreq.1.2.times.the distance of G, and the distance of B.gtoreq.the distance G. The axial length L of the flat face and the area S of a cross section perpendicular to the flat face should, preferably, have the relation S/L.gtoreq.0.7.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.