SPARK PLUG FOR INTERNAL COMBUSTION ENGINE Russian patent published in 2000 - IPC

FIELD: mechanical engineering; electrical equipment of internal combustion engines. SUBSTANCE: proposed invention relates to devices providing ignition of fuel mixture in carburetor engine. Spark plug has metal shell accommodating rigidly secured ceramic insulator with central rod electrode. Shell has converging and diverging nozzles forming microprechamber together with shell. Converging nozzle is made in form of swirler, and adapter part between nozzles, in form of cylindrical belt forming, with central electrode, a ring spark gap. Volume of prechamber V is related to section area of ring gas S by equation 12S<V<15S where V is volume, cm³ and S is area, cm³. Working surfaces of central electrode and cylindrical belt feature highly developed microrelief, roughness R_a= 0,2-0,16μm, being furnished with electric erosion-resistant coating, for instance, tungsten carbide. Such spark plug operates on principle of combination of impulse acceleration of plasma and precombustion chamber ignition. EFFECT: simplified design of spark plug, reduced overall dimensions, improved combustion of fuel and heat operating conditions of spark plug. 2 cl, 1 dwg