Method and apparatus in electronic ignition systems for internal combustion engine.

摘要

In a method of improving the ignition for electronic ignition systems of the multiple spark type, particularly for difficult operational conditions, the energy required for ignition is stored in the form of magnetic energy in the magnetic core of the ignition coil. The first spark is furthermore given longer duration than the following sparks in every shower of sparks during an ignition period. An apparatus in electronic ignition systems for providing multiple sparks of different durations, particularly during the starting sequence, includes a logical circuit (4) adapted to control a transistor (TR3) to ON and OFF at predetermined times. The transistor is coupled in series with the primary winding of the ignition coil (2), whereby the magnetic energy stored in the magnetic core of the ignition coil generates a spark via the secondary winding of the coil during each opening interval of the transistor. The logical circuit is further arranged to keep the transistor open during an ignition period with a first interval which is longer than succeeding intervals. In order to make closing and opening of the contact breaker points more reliable in an electronic ignition system which contact breaker points for internal combustion engine, a circuit (TR3, D1, C1, R1, R2, C2) is arranged to generate a high voltage, considerably exceeding the battery voltage (12V) across the points (BR) and send a high current through the points when they are closed.