Integrated converter high power CD ignition

A capacitive discharge, CD, ignition system including a CD circuit defined by at least one energy storage and discharge capacitor of capacitance C, at least one separate resonating inductor of inductance Le, and one or more ignition coils Ti where i=1, 2, 3, . . . , of turns ratio N defined by the secondary coil winding turns Ns divided by the primary turns Np, coil primary current switch means SCi, said CD circuit having a spark pulse firing discharge period T, and said CD ignition system including an essentially DC power source means for supplying power to the ignition system by charging up said capacitor C, the improvement comprising the connection of said power source through switch S across the ends of said inductor defining an integrated converter, the system constructed and arranged such that upon the ignition system operation said switch means S is off for the spark discharge cycle of any spark pulses, and at a subsequent time is turned-on to conduct current through said inductor from said power source until a predetermined peak current IO is reached which stores energy E1 equal to 1/2*Le*(IO)**2 in said inductor, whereupon switch S is turned off and said current IO flows in a complete circuit including said capacitor C to deposit charge on the positive plate of the capacitor to help restore its charge.

A capacitive discharge, CD, ignition circuit comprised of a series connection from ground of a coil primary current switch means SC comprised of a switch SC1 and shunt diode, an energy storage and discharge capacitor C, a primary winding of a coil T, and a resonating inductor of inductance Le with its one end returned to ground, said CD circuit having an inductor of inductance L0 connected to the intersection of said switch and capacitor defined as the auxiliary feed point, and said inductor connected to a voltage source, the system being constructed and arranged such that when switch SC is turned on to produce a spark pulse current flows through inductor L0 during the discharge period and is delivered to said capacitor after the end of the spark pulse.

A very high power high energy, VHE, ignition system comprising a CD ignition circuit and including one or more toroidal spark plugs, each spark plug having a central tip at the end of an insulating nose section of length l1 protruding from the end of a surrounding shell and defining a gap "g" between surface of said nose section and inside surface of said shell at the shhell end, where l1 is approximately equal to or greater than twice the size of gap g, the system constructed and arranged to fire a train of spark pulses between said tip and shell end such that in normal operation of an IC engine, and a defined acceptable life-time of the plug, material deposited on the insulating nose is readily oxidized to form essentially non-conducting or poorly conducting oxides whose resistance along the nose length is of the order of magnitude and greater than 10,000 ohms, i.e. greater than 1,000 ohms.

A capacitive discharge, CD, ignition system including a CD circuit defined by at least one energy storage and discharge capacitor of capacitance C, at least one separate resonating inductor of inductance Le usable for also connecting a power supply to it for charging capacitor C, and one or more ignition coils Ti for igniting air-fuel mixtures in engines where i=1, 2, 3, . . . , of turns ratio N defined by the secondary coil winding turns Ns divided by the primary turns Np, coil primary current switch means SCi, said CD circuit having a spark pulse firing discharge period T and a gate period Tgon over which a train of multiple firing spark pulses is produced for igniting air-fuel mixtures and a period Tgoff over which no mixture igniting spark firing occurs, and said CD ignition system including an essentially DC power source means for supplying power to the ignition system by charging up said capacitor C, said system further including coil TE and switch means for energizing the coil, said coil TE having its output connected to a sparking device in the exhaust system of said engine wherein said coil is energized and fired during the period Tgoff when the mixture ignition sparks are not fired to ignite unburnt fuel in the exhaust stream.