IGNITION SYSTEM OF INTERNAL COMBUSTION ENGINE Russian patent published in 2006 - IPC F02P3/02 

FIELD: automotive industry; spark ignition systems.

SUBSTANCE: according to invention, ignition system of internal combustion engine contain ignition coil consisting of primary and secondary windings and magnetic circuit, and spark gap placed in circuit of secondary winding of ignition coil. Ignition coil is made so that wave impedance ρ of oscillatory circuit formed by inductance and effective capacitance in secondary winding with due account of leakage currents is within where U_j is minimum voltage at spark gap at which spark jumps the gap, I_t is maximum tolerable current of spark discharge at which spark does not change into low-voltage arc discharge. Windings of ignition coil can be made, with increased magnetic field leakage flux, in form of pie, and magnetic circuit of ignition coil can be made of material with low specific losses for instance, of transformer iron designed for frequency of 400 Hz.

EFFECT: increased power of spark and improved reliability of formation of spark in ignition system with resulting improved reliability of operation of engine at low temperatures and/or high humidity and at poor quality of fuel-air mixture.