DEVICE FOR IGNITING AND BURNING FUEL MIXTURE IN INTERNAL-COMBUSTION ENGINES Russian patent published in 1999 - IPC

FIELD: engine manufacture. SUBSTANCE: spark plug incorporating first and second central electrodes has its second electrode made in the form of shaped loop embedded in head body and provided with U-shaped bosses over its length formed by wire-wound metal core placed in insulating braid; core ends are, essentially, spirals one of which is mounted on periphery of annular insert and other spiral is arranged in center; they are held tight against plug body and electrode, respectively, to ensure electric contact between them. EFFECT: improved service life of spark plug. 3 cl, 3 dwg