SPARK PLUG Russian patent published in 2000 - IPC

FIELD: electrical equipment for internal combustion engines. SUBSTANCE: device has solid housing, which conducts electric current and heat, and connectors. Inner chamber of housing comprises ceramic insulator with central electrode, which extending shed has at least one ring-shaped additional electrode, which is located on extending member of ceramic insulator and provides spark gap with one housing end and central electrode. Outer edges of additional ring-shaped electrode have boss. EFFECT: increased reliability and service life. 8 cl, 4 dwg