Patent · US Expired

Spark plug with creepage spark gap

US4870319A · kind A · utility

13Cited by

6References

3Claims

0Family size

Assignee

Robert Bosch GmbH · DE

Inventors

Walter Benedikt
Werner Herden · Gerlingen, DE
Jurgen Schmatz · Mundelsheim, DE
Siegbert Schwab · Sindelfingen, DE

Key dates

Filing date	Jan 13, 1988
Grant date	Sep 26, 1989
Priority date	—
Expiry date	Jan 13, 2008

Classification

Technology area (CPC H)Electricity
CPC primaryH01T13/52
WIPO fieldElectrical machinery, apparatus, energy
WIPO sectorElectrical engineering

Abstract

A spark plug with creepage spark gap for internal combustion engines includes a plug housing having an annular side electrode, an insulator, surrounded by the plug housing over a longitudinal section, and a central electrode. The layer lies in a through-bore of the insulator and is exposed on the combustion chamber end side. The creepage spark gap is formed between the central electrode and the side electrode along a slideway on the surface of the insulator. To achieve a small plug capacitance with high-dielectric slideway, the insulator has, at least at the end section on the combustion chamber side, at least two coaxial material layers, having very different dielectric constants. These coaxial layers lie or partially lie against each other in a radial direction of the spark plug.

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