Patent ID: 7971476
Filing Date: 2011-07-05
Classification: F02D

Abstract:
1. A method for identifying various phases of ionization current released during combustion in each cylinder of an internal combustion engine fitted with one or more cylinders, having a control unit, and a device to produce the ionization current (IC) located above each cylinder, comprising a coil, a spark plug, a polarisation circuit and an acquisition circuit, wherein said method comprises the following phases: measurement, in each cylinder of said engine, of the ionization current signal from the end of the spark occurring in the spark plug through to the end of the ionization phenomenon (IC); selection of samples of said ionization current IC signal at predetermined intervals of time within windows which vary from 5 μs to 50 μs (S); registration of the signal samples S; calculation of the value of the derivative of each signal sample S (S association of each sample signal S with the corresponding value S ordering of the values S comparison of each value S registration of each sample signal S corresponding to the value S measurement of each length of time that lapses between the end of the spark occurring in the spark plug and the instant the value P is registered (TP); and registration of the lengths of time TP.