Method for actuating a spark gap

A method for actuating a spark gap in an internal combustion engine in which the spark gap is assigned a first ignition coil and a second ignition coil, each of which has a primary winding and a secondary winding that are inductively coupled to one another, the method comprising the following steps:

• (a) triggered by a start signal, charging the primary winding of the first ignition coil and with a delay D, for which 0≦D, charging the primary winding of the second ignition coil by supplying a direct current, wherein, whilst each primary winding is charged, the respective secondary winding is blocked;
• (b) measuring the total primary current supplied to the primary windings;
• (c) after a period T, abruptly discharging the primary winding of the first ignition coil, and with the delay D abruptly discharging the primary winding of the second ignition coil, whereby secondary currents are induced in the respective secondary windings, which lead to an electrical discharge between two electrodes of the spark gap;
• (d) measuring the total secondary current flowing through the spark gap;
• (e) thereafter alternately starting the charging of the primary winding of the first ignition coil and the primary winding of the second ignition coil whenever the strength of the secondary current flowing through the first or second ignition coil respectively falls below a threshold;
• (f) then abruptly discharging the primary windings whenever the strength of the total secondary current falls to a lower threshold or whenever the strength of the total primary current rises to an upper threshold;
• (g) repeating steps (e) and (f) until the duration of the discharge process between two electrodes of the spark gap reaches a predefined value Z;
• and
• (h) thereafter both primary windings remain separated from the supply of direct current until a further start signal occurs and the above sequence of steps is restarted with step (a).

A method for actuating a spark gap in an internal combustion engine in which the spark gap is assigned a first ignition coil and a second ignition coil, each of which has a primary winding and a secondary winding that are inductively coupled to one another, the method comprising the following steps:

• (a) triggered by a start signal, charging the primary winding of the first ignition coil and with a delay D, for which 0≦D, charging the primary winding of the second ignition coil by supplying a direct current, wherein, whilst each primary winding is charged, the respective secondary winding is blocked;
• (b) measuring the total primary current supplied to the primary windings;
• (c) after a period T, abruptly discharging the primary winding of the first ignition coil, and with the delay D abruptly discharging the primary winding of the second ignition coil, whereby secondary currents are induced in the respective secondary windings, which lead to an electrical discharge between two electrodes of the spark gap;
• (d) measuring the total secondary current flowing through the spark gap;
• (e) thereafter alternately starting charging of the primary winding of the first ignition coil and charging of the primary winding of the second ignition coil whenever a given time interval t1 or t2, respectively, ends, which is started whenever the strength of the total secondary current falls to a lower threshold or whenever the strength of the total primary current rises to an upper threshold;
• (f) then abruptly discharging the primary windings whenever the strength of the total secondary current falls to a lower threshold or whenever the strength of the total primary current rises to an upper threshold;
• (g) repeating steps (e) and (f) until the duration of the discharge process between two electrodes of the spark gap reaches a predefined value Z;
• and
• (h) thereafter both primary windings remain separated from the supply of direct current until there occurs a further start signal and the above sequence of steps is restarted with step (a).

A method for actuating one or more spark gaps in an internal combustion engine, in which the spark gaps are assigned a first ignition coil and a second ignition coil, each of which has a primary winding and a secondary winding that are coupled inductively to one another, the method comprising the following steps:

• (a) starting from a desired ignition time-point, the first ignition coil is charged during a prior period, and with an offset over time D>0 the charging of the second ignition coil is initiated;
• (b) once the discharge of the first ignition coil has started, the following discharging onsets and charging onsets of the two ignition coils are alternately controlled whereby time intervals between the following discharging onsets and charging onsets of the two ignition coils are not predefined and such that a continuous discharge current at the spark gap produces an uninterrupted, extended spark and the ignition coils are controlled on the basis of monitoring at least two of the following:
• thresholds of amperage of individual primary currents;
• thresholds of amperage of individual secondary currents;
• thresholds of amperage of total primary current;
• thresholds of amperage of total secondary current;
• and
• the end of time intervals t1 and t2 at which charging the ignition coils is started.