Global Patent Index - EP 0989646 A1

EP 0989646 A1 20000329 - Spark Plug and ignition system for use with internal combustion engine

Title (en)

Spark Plug and ignition system for use with internal combustion engine

Title (de)

Zündkerze und Zündanordnung zur Anwendung in einem Verbrennungsmotor

Title (fr)

Bougie d'allumage et système d'allumage pour utilisation dans un moteur à combustion interne


EP 0989646 A1 20000329 (EN)


EP 99307498 A 19990922


  • EP 99307498 A 19990922
  • EP 99306552 A 19990819
  • JP 26825598 A 19980922

Abstract (en)

A spark plug (100) includes a spark portion (31, 32) of an Ir-based metal and a resistor (15) disposed between a center electrode (3) and a metallic terminal (13) and adapted to establish an electric resistance of not less than 10 k OMEGA , preferably not less than 15 k OMEGA , as measured between the center electrode (3) and the metallic terminal (13). Thus, even in a system in which an ignition coil (51) is connected directly to the spark plug (100) without use of a high tension cable, an electrical discharge with a relatively weak current, such as a glow discharge, can be maintained stably, so that even at high-speed or heavy-load operation, consumption of the spark portion (31, 32) caused by volatilization of Ir through oxidation can be suppressed, thereby extending spark plug life. <IMAGE>

IPC 1-7

H01T 13/39; H01T 13/41

IPC 8 full level

H01T 13/39 (2006.01); H01T 13/41 (2006.01)

CPC (source: EP)

H01T 13/39 (2013.01); H01T 13/41 (2013.01); F02B 2275/18 (2013.01)

Citation (search report)

Designated contracting state (EPC)


DOCDB simple family (publication)

EP 0989646 A1 20000329; EP 0989646 B1 20010321

DOCDB simple family (application)

EP 99307498 A 19990922