IGNITION DEVICE OF INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To further restrain variation of a resonance frequency of a combustion chamber in an ignition region than conventional.SOLUTION: An ignition device 10 of an internal combustion engine comprises: a combustion chamber 12 provided in a cylinder 20 and burning air-fuel mixture; a piston 14 arranged in the cylinder 20 and moved in the cylinder 20 by combustion; and electric field generation means 16 provided on a ceiling face 24 of the combustion chamber 12 opposed to a top face 22 of the piston 14 faced to the combustion chamber 12, and burning the air-fuel mixture by generating an electric field in the combustion chamber 12. Furthermore, the ceiling face 24 has a plane shape that is not flush, and the top face 22 is formed so that a separation distance between the top face 22 of the piston 14 and the ceiling face 24 in a moving direction of the piston 14 is almost constant on the entire face.