Patent ID: 6032657
Filing Date: 2000-03-07
Classification: F02P

Abstract:
An ignition system for internal combustion engines with spark ignition, the system comprising:an ignition coil having a primary winding and a secondary winding,a spark plug connected to the secondary winding and capable of producing a spark whenever a voltage at terminals of the spark plug exceeds a predetermined threshold value,an electric supply circuit associated with the primary winding and including a semiconductor device that can be cyclically switched between a first and a second operating position so as to produce a charging cycle in the course of which instantaneous current flowing in the primary winding gradually increases from a minimum value to a maximum value and then returns brusquely to the minimum value in such a manner as to produce a discharge cycle in the course of which instantaneous current flowing in the secondary winding gradually reduces from a maximum value to a minimum value,an electronic control unit capable of controlling the switching movements of the semiconductor device as a function of appropriate engine operating parameters, andcombustion control means capable of providing during each engine cycle an electric signal that indicates whether combustion has or has not occurred in the combustion chamber and is obtained as a function of the growth rate of the primary current,wherein the electronic control unit is programmed to produce a succession of charging and discharge cycles during one and the same engine cycle, each of the charging cycles being separated from the previous charging cycle by a time interval equal to or greater than the duration of a discharge cycle.