SPARK PLUG FOR INTERNAL COMBUSTION ENGINE Russian patent published in 2002 - IPC

FIELD: ignition systems for automobile, aircraft, and other internal-combustion engines. SUBSTANCE: spark plug has body accommodating insulator, rod-type center electrode secured in central bore of insulator so that its working end protrudes beyond insulator end, annular electrode with central through space protruding beyond end of center electrode, and precombustion chamber in annular electrode which is arranged around center electrode and communicates with engine combustion chamber. Precombustion chamber has main and additional chambers intercommunicating through annular gap between depression bottom and insulator end; spark gap is formed by side surface of center electrode working end and inner surface of main chamber. EFFECT: enhanced operating efficiency, improved performance characteristics of plug. 5 cl, 1 dwg