WO1993000512A1 - Process for controlling a static ignition distribution system - Google Patents

Abstract

The invention relates to a process for controlling a static ignition distribution system in an internal combustion engine with a gear wheel allocated to a crankshaft and at least two ignition coils, in which the sequence of making and ignition occurrences in the ignition coils is determined dependently upon revolution speed ranges determinable by transmission tooth increment thresholds.

Description

Method for controlling a stationary ignition distribution

State of the art

The invention relates to a method for controlling a static ignition distribution of an internal combustion engine according to the preamble of claim 1.

/

Methods for realizing a static ignition distribution with overlapping closing angles for internal combustion engines are known which have relatively long program run times and a high internal memory requirement (RAM requirement), so that expensive hardware is required for their use.

Advantages of the invention

In contrast, the method according to the invention has the advantage that very precise control of the ignition is possible with a relatively simple control effort short program run times and the memory requirement is low. In particular, by determining the sequence of the closing and ignition events of the ignition coils as a function of speed ranges, which are determined by encoder tooth increment thresholds, the events can be determined with relatively little effort.

A method is preferred in which the selected ignition coil is also selected as a function of encoder tooth increment thresholds. In this way, the existing ignition coils can be controlled in a simple manner, that is to say that the program run times for such control are relatively short.

A preferred embodiment of the method is characterized in that at least one of the encoder tooth increments is variable. This ensures that flexible adaptation to current operating states is possible with little technical effort.

In addition, a method is preferred in which the encoder tooth increment thresholds take place as a function of electrical properties of the ignition coil or as a function of the instantaneous level of the supply voltage. It is thus possible to adapt the ignition distribution method to specific circumstances of the controlled internal combustion engine and its voltage supply.

In a further preferred embodiment of the method, in which the closing angle is dependent on speed is determined by the closing time and the speed of the internal combustion engine, the segment of the associated closing event is determined on the basis of an ignition event of an ignition coil as a function of the already determined encoder tooth increment thresholds. With such a method, the segment of the closing event can be determined relatively easily, so that short program run times are ensured.

A further embodiment of the method is characterized in that the position of the closing event of a specific ignition coil within a segment is determined by the speed, an encoder tooth increment and / or the ignition angle. With such a determination of the closing event, the computational effort can be minimized, so that a relatively precise fixing of the closing event can be determined without a large computer load.

In a further preferred embodiment of the method, in which the closing angle is determined as a function of the closing time and speed, starting from an ignition event of an ignition coil, its closing event is determined by the teeth being detected by a suitable sensor of one of the crankshafts of the Internal combustion engine associated gear, which are to be detected during the closing of the coil is set. In this way, a very exact fixing of the closing event is possible with relatively little effort. Another preferred embodiment of the method is one in which the number of teeth to be detected is determined as a function of the predetermined speed range. By means of this method, the closing event can be easily determined over other speed ranges.

An embodiment of the method is particularly preferred in which the ignition coil to be controlled is determined as a function of whether an encoder tooth increment threshold is exceeded from bottom to top or from top to bottom. This criterion is easy to determine, as a result of which the activation of the corresponding ignition coil requires only short program run times.

drawing

The invention is explained in more detail below with reference to the drawing. Show it:

Figure la the closing and ignition events of three ignition coils of an internal combustion engine during a first operating state of low speed;

FIG. 1b shows the closing and ignition events of three ignition coils of an internal combustion engine after a first speed threshold has been exceeded,

Figures lc and ld the closing and ignition events of three ignition coils of an internal combustion engine after exceeding a second and third encoder tooth increment threshold with closing angle overlap;

FIG. 2 shows three pie charts to clarify the determination of the closing event of an ignition coil;

FIG. 3a charging phases of three ignition coils at a speed of 1000 rpm of the internal combustion engine;

FIG. 3b charging phases of three ignition coils at a speed of 3000 rpm of the internal combustion engine;

3c charging phases of three ignition coils at a speed of 5000 rpm of the internal combustion engine;

Figure 3d charging phases of three ignition coils at a speed of 6000 rpm of the internal combustion engine;

FIG. 4 charging phases of three ignition coils in a dynamic operating state of the internal combustion engine and

Figure 5 is a schematic diagram of a control system of an internal combustion engine with six cylinders and with individual ignition coils.

Description of the embodiments

In Figures la to ld the closing and ignition events of three ignition coils are one above the other The ignition coil 1, including the ignition coil 2 and finally the third ignition coil 3 as the bottom, is shown in the uppermost diagram. The abscissa denotes the crank angle or the time. The closing event or detonator event of the respective ignition coils is identified by the large letters S and Z, the closing / ignition events of the ignition coils 1 to 3 being designated by the indices. In addition, the triggering of the ignition spark is identified by a lightning symbol. Different time or angle segments are distinguished by vertical lines marked with trl, tr2, tr3. It can be seen that two crankshaft revolutions are to be indicated here in FIGS. 1a to 1d.

The closing and ignition events of the three ignition coils in these figures are shown for four different speed ranges of the associated internal combustion engine, the speed increasing from figure la to figure id. Between the individual representations, the associated speed ranges, there is a swelling of encoder tooth incre, the definition of which will be discussed in more detail below. Thus, the operating state in FIG. 1a is to be distinguished from that shown in FIG. 1b by a first encoder tooth increment threshold, a second encoder tooth incursion lies between the operating states shown in FIG. 1b and FIG. 1c, finally there is between the Operating states according to Figure lc and Figure ld defines a third threshold. It can be seen from the illustration according to FIG. 1 a that the speed of the internal combustion engine is so low that the closing and ignition event of one and the same spark plug lies within a segment. This means that the ignition coil's closing event lies in the segment in which its energy is to be released by ignition. The ignition coil is closed according to the tr brand. In the operating state shown in FIG. 1 a, the internal combustion engine rotates at a low speed n.

It can be seen from the illustration in FIG. 1 a that a certain time or a certain angle of rotation elapses after the ignition process of a spark plug before a closing event takes place in another ignition coil.

In the first segment according to FIG. 1 a, it is made clear by S2 that the closing event of the coil 2 is located here. Z2 indicates that the ignition event of this second ignition coil is also in this segment.

The closing event S3 and the ignition event Z3 of the third coil lie in the second segment according to FIG. 1a, and both the closing event S1 and the ignition event ZI of the first coil lie in the subsequent segment. The events mentioned then repeat themselves cyclically.

The case identified in FIG. 1a is also identified by a large A standing in a circle. It can be seen from FIG. 1b, which is also identified as case B, that the closing and ignition events of one and the same spark plug fall into two separate, successive segments. It can be seen that a closing event of one ignition coil coincides with the ignition event of another ignition coil at the same time. Thus, in the first segment according to FIG. 1b, the ignition event Z2 of the ignition coil 2 coincides with the closing event S3 of the ignition coil 3. In segment 2, the ignition event Z3 of the ignition coil 3 and the closing event S1 of the ignition coil 1 also take place at the same time . The ignition event ZI of the first coil and the closing event S2 of the second coil, etc. are in the following third segment. The closing events are again identified by S and the corresponding index, the ignition events by Z and the associated index of the ignition coil concerned.

A further increase in the speed of the internal combustion engine changes the relationships shown in FIG. 1b: according to FIGS. 1c and 1d, there are overlapping closing angles. It should be noted that a closing angle of an ignition coil is given by the period of time or the angle of rotation distance between the closing event and the ignition event.

While in case B-figure lb- the closing angle is smaller than the length of a segment, in case C, which is shown in FIG. 1c, it can be seen that the closing angle of the ignition coils overlaps extends an area that is longer than a segment.

From Figure lc it can be seen that the closing event S3 of the coil 3 is in the first segment and that the associated ignition event Z3 is in the second segment. While the ignition coil 3 is being charged, the ignition coil 1 is also being charged. Their normally open event S1 is at the beginning of the second segment, and the associated ignition event ZI is in the third segment. While the ignition coil 1 is being charged, the ignition coil 3 is being discharged. Shortly thereafter, the ignition coil 2 is loaded in the third segment, its closing event S2 is at the beginning of the third segment.

It should be noted that the closing event of one coil falls in the period in which another coil is already being charged. In this way, the closing angle overlaps mentioned result. The speed in case C is however still so low that, for example, there is a brief pause between the ignition event ZI of the ignition coil 1 and the closing event Z3 of the ignition coil 3.

When the next, third encoder tooth increment threshold is exceeded, the ignition method changes to the next operating state, which is shown in FIG. 1d and is identified with case D. The closing angle overlap increases so that the ignition event of a coil, here the ignition event ZI of the coil 1, coincides with the closer ignis of another coil, here the closing event S3 of the ignition coil 3. Both events take place while the second ignition coil is still being charged. In each segment there are again two events: in the first segment the ignition event Z2 of coil 2 and the closing event S1 of coil 1. Correspondingly, in the second segment the ignition event Z3 of coil 3 and the closing event S2 of coil 2. The corresponding Events result from the other segments.

In case D, the closing angle, that is the distance between a closing and an ignition event, becomes so large that it extends over two tr marks. After the ignition of one coil, the next but one is charged. It can be seen from FIG. 1d that the closing angle thus covers three segments.

The largest possible closing angles in the respective speed ranges are shown in FIGS. 1b to 1d. If the closing angle is increased further, the next case is reached. In the method shown here, the closing angle can reach a maximum of 240 ° KW.

If a closing angle of more than 240 ° KW is to be achieved, a residual open angle monitoring must be carried out in order to ensure the necessary discharge duration of the ignition coil.

FIG. 2 again shows the four cases A to D which are different in FIG. 1, the following being shown: In the uppermost pie chart according to FIG. 2 it is made clear for case A that the closing and ignition event are in a single segment fall. It can be seen from the second pie chart in FIG. 2 that for cases B and C the ignition event takes place in one segment, while the associated closing event is shifted by one segment.

Finally, it can be seen from the bottom circular diagram from FIG. 2 that the closing event of a coil is shifted by two segments compared to the ignition event.

The more precise relationships between the ignition and closing events will be discussed below.

In the diagrams according to FIG. 3, the charging phases of the individual ignition coils, which are limited by the closing and ignition event, are shown above the crank angle, which is given in degrees. The abscissa extends over a range of 1800 ° KW. The charging phases of the ignition coil 1, 2 and 3 are shown one above the other, the diagram of the ignition coil 1 below, that of the ignition coil 2 in the middle and that of the ignition coil 3 above.

The representations according to FIGS. 3a to 3d show examples. They differ in different speed ranges. While a speed n of 1000 rpm is selected in FIG. 3a, the illustration according to FIG. 3b relates to a speed of 3000 rpm, that of 3c n = 5000 rpm and that of FIG. 3d a speed n of 6000 rpm. min.

It is readily apparent that in order to achieve the necessary energy within the ignition coil, the charging phases increase with increasing speed. 3c, a longer closing angle overlap takes place, as already described with reference to FIGS. 1a to 1d, which assumes its maximum value in FIG. 3d. In contrast, it is clear that in FIG. 3a there is a visible angular distance between the ignition event of the one coil and the closing event of the ignition coil controlled thereafter. This distance is reduced to zero in FIG. 3b, that is to say the ignition event, for example of ignition coil 2, coincides with the closing event of ignition coil 1, while its ignition event coincides with the closing event of ignition coil 3.

FIG. 4 shows the closing and ignition events of three ignition coils one above the other, the crank angle in degrees being plotted along the abscissa and the speed n in rpm being plotted on the ordinate. The speed is drawn in a triangular manner above the charging phases shown in dashed lines with a continuous line. It is clear from the diagram that the speed increases during a freely selected range of a total of 10 revolutions from approximately 2500 rpm to just under 4000 rpm and then drops again to the initial value.

The dynamic behavior of the ignition control is to be explained on the basis of this representation:

In the lowest area of the increasing speed curve, approximately up to 720 ° KW, there is a distance between the ignition event of the one ignition coil and the closing event of the. next ignition coil can be seen. In the subsequent range between 720 ° KW to about The ignition event of an ignition coil and the closing event of the subsequently activated ignition coil coincide with almost 1400 ° KW.

Due to the increasing speed, the associated encoder tooth increment threshold between case B and case C shown in FIGS. 1 and 3 is finally exceeded, so that finally a closing angle overlap occurs, which is approximately between 1400 ° KW and approximately 2000 ° KW. This means that the overlapping charging phases of the different ignition coils are: First, the charging phase of the ignition coil 1 with that of the ignition coil 3; the charging phase of the ignition coil 2 also falls later in the charging phase of the ignition coil 3. While this is being charged, the closing event of the ignition coil 1 is finally initiated. The closing angle overlaps result more clearly from FIGS. 1c and 1d and 3c and 3d. According to FIG. 4, the area of the closing angle overlap with decreasing rotational speed is in turn followed by an area in which the charging phases of the various ignition coils directly adjoin one another. Finally, a clear distance between the individual charging phases can be seen when the speed has dropped further.

From the representations in the figures it can be seen without further ado that the control of the individual ignition coils takes place as a function of the rotational speed, the sequence of the closing and ignition events of the individual ignition coils being determined as a function of specific speed ranges . These are determined by encoder tooth increment thresholds. differed, as was explained with reference to the figures.

The various speed ranges are selected such that a closing angle is set so large that the energy required to generate the ignition spark is fed into the ignition coil. To ensure this, the encoder tooth increment thresholds are designed to be variable, in particular they are determined as a function of the electrical parameters of the individual ignition coils. Depending on the ignition coil, a larger or smaller closing angle can therefore be specified.

In addition, it is also possible to influence the encoder tooth increment thresholds and thus the specified speed ranges as a function of the supply voltage of the internal combustion engine. If the battery voltage drops, the closing angle is extended due to the present method so that sufficient energy is fed into the ignition coils.

From the previous explanations it is clear that the ignition and closing events of the ignition coils can fall into different segments depending on the specific speed ranges. Figures la to ld show that the ignition event of an ignition coil is close to a tr mark, which are shown in figures la to ld. In Figure 2, the numbers 1, 2 and 3 are chosen to designate these brands.

In order depending on the speed and the named parameters (coil data and battery voltage) To ensure the necessary ignition energy, the associated closing event of the corresponding coil must be predetermined for an ignition event of a coil.

This can be done in two different ways: firstly, a rough definition of the segment into which the closing event falls can be carried out, while the position of the closing event within this segment is then defined more precisely. It is also possible to determine in a suitable manner the number of teeth of a gearwheel assigned to the crankshaft which has to be counted during the charging phase of an ignition coil, that is to say that the closing angle of an ignition coil is defined by the number of teeth counted.

In the first-mentioned method, the control of the closing angle is carried out with the aid of an ignition counter IZX, an ignition coil counter IZS and an ignition control counter ZZ. The counter reading in the ignition counter IZX determines which of the ignition coils 1, 2 or 3 is to be discharged in a certain segment. The status of the ignition coil counter IZS indicates the ignition coil 1, 2 or 3, which is to be loaded in this segment. The ignition control counter ZZ controls these events in a conventional manner, so that a more detailed description is dispensed with. The ignition coil to be charged is selected according to the following equation:

IZS = IZX + ILX (1). ILX is the speed range-dependent offset that indicates the number of segments that must lie between the ignition event of an ignition coil and its closing event.

It can be seen from FIG. 2 that for case A the speed range-dependent offset ILX assumes the value 0 because the ignition coil, the ignition event of which is in a segment, is to be loaded in the same segment; its closing event therefore falls in the segment in which the ignition event is located.

For cases B and C explained with reference to FIG. 1, the speed range-dependent offset ILX according to FIG. 2 (central pie chart) assumes the value 1. The result of this is that the ignition coil to be charged is ignited in the next segment, that is to say that the closing event and the ignition event of an ignition coil fall into two successive different segments.

Finally, in the bottom diagram of FIG. 2, the speed range-dependent offset ILX with the value 2 indicates that the ignition coil to be charged is ignited in the next but one segment, that is, as shown in FIG. 1d, the closing event and the ignition event of one and the same The ignition coil does not fall into successive segments, but rather that there is a segment in between. In other words, the closing angle of the ignition coil is so large that the closing event of this coil falls into one segment and its ignition event into the next segment. From the above-mentioned equation (1) it follows that an ignition coil is skipped during the transition of the closing event via a tr mark without additional measures. This concerns the transitions between case A and case B on the one hand and between case C and case D on the other

In case A, ILX = 0 and in case B, ILX = 1. A Δ ILX = 1 is thus obtained. ILX = 1 also applies to case C and ILX = 2 applies to case D. Here, too, there is a difference of SILX = 1. The count of the ignition counter IZX changes in each segment according to FIG. 2, so that the value IZS resulting from equation (1) changes by the value 2 during the transition from A to B or C to D. The transition from case A to case B is to be illustrated using the following numbers for two successive ignition processes:

Ignition process n - 1 for case A: IZX = 2; ILX = 0. Therefore, the following applies to IZS: IZS = 2.

Ignition process n for case B: IZX = 3; ILX = 1; therefore the following applies to the state of the ignition coil counter IZS: IZS = 1. The value IZS = 3 was omitted. If the count of the ignition coil counter IZS assumes a value of> 3, this counter is set to the value 1 because after the 3rd ignition coil the first should be loaded again.

It can be seen that ILX changes at the transition to a tr mark. The reason is that the closing, like the ignition, is controlled from the beginning of the segment in accordance with the tr brands, in each case for the current segment. In case B the closing should have happened through the transition at the end of the last segment, which is not possible in principle. Therefore, when a corresponding transition is recognized at the tr mark, the ignition coil in question is positively closed. This measure has no external impact. The additional closing is therefore not noticeable. However, it is ensured that the closing process functions properly and dynamically.

Within the speed ranges defined by the encoder tooth increment thresholds, the closing angle is set more precisely using the ignition control counter ZZ.

The closing process is controlled individually in the following way:

The ignition control counter ZZ is loaded with the number of encoder increments which, calculated from the tr mark, must still occur before the closing process can be initiated, ie before the associated coil can be closed.

For example, there is a requirement that 36 ° KW should be closed after the tr mark. This value of the crank angle is divided by the encoder tooth width of, for example, 6 °. It follows from this that the value 36/6, ie the number "6 ¹¹ , must be loaded into the ignition taxpayer ZZ. In the numerical example chosen here it was assumed that a toothed disk was used as the encoder wheel, which is rigidly connected to the crankshaft with 60 teeth is selected, from which it can be deduced that a single increment tooth extends over 6 ° KW. This value is also referred to as L _z .

The encoder tooth increments Z are calculated using the following formula

360 ° • N _ms • SZ Z = (2)

^L Z

In addition to the known names, the following information is used here: SZ denotes the closing time (measured in ms) and N _ms the number of crankshaft revolutions per millisecond.

It is noted in more detail below that the size of the tooth increment thresholds depends on the ignition angle.

The value loaded into the ignition control counter ZZ is then calculated by starting from a lower encoder increment threshold Z 'and by counting the number of teeth per segment around the lower encoder increment threshold as the value to be loaded into the ignition control counter ZZ Z ^{1 is} reduced.

It is particularly advantageous that the closing angle can be controlled to 6 ° to 3 ° KW in this way even without the use of a timer.

Since the speed ranges are determined by the variable encoder tooth increments, the current battery voltage and the coil data are included in the calculation of the respective charging time. The encoder tooth increment thresholds ^{' are} grounded according to the Percentage change in loading time postponed. In this way, these methods dispense with the use of a map for the closing angle.

The distinction between the four cases A to D ensures that the control functions of the ignition control counter ZZ do not come into conflict with one another, because both ignition and closing are controlled via this counter.

In order to avoid malfunctions of the method, additional coercive measures can be integrated into the method: in addition to positive ignition after top dead center of a piston, depending on the speed range, before ignition - this applies to cases A and C - or after tr mark - this applies to cases B and D- if the closing event of an ignition coil has not been initiated in this or in the previous segment by the given time.

According to the other method, the closing angle resulting from the closing time and the speed is determined on the basis of the number of teeth counted on a gear wheel of the internal combustion engine assigned to the crankshaft, the desired closing angle also being reached when a predetermined number of teeth is reached. In this method, the closing angle is set based on the number of tooth increments over which an ignition coil must be closed.

In this method, the selection of the control range with which the closing angle is determined is based on the tooth increments Z. a segment, as defined in FIG. 1 for a six-cylinder engine, sweeps 20 tooth increments. The number of tooth increments, according to which the ignition is triggered - calculated from the tr mark (beginning of the segment) - should be 8, for example. This results in the following division of area by the encoder tooth increment thresholds:

40> Z> 28 area D

28> Z> 20 area C

20> Z> 8 area B

8> Z> 0 area A

In the start area with Z = 0, in which the closing angle cannot be controlled in these processes, the closing angle is controlled with the aid of a timer control.

It is particularly advantageous that with this method a direct coupling of the start of closing to the ignition of the coil is possible. In particular, a transition from one control area to the adjacent can be effected solely by changing the ignition angle, which depends on the respective operating state of the internal combustion engine. In principle, dynamic changes in the ignition angle after the ignition coil is closed further shorten or extend the closing time. The size of the individual control areas is determined by the respective firing angle and the position of the tr mark.

With this method, the closing time is controlled correctly independently of these parameters. The program runtime is shortened in each individual segment.

Another advantage of this method is that the actual closing time of an ignition coil as a function of the battery voltage is stored as a characteristic. The desired closing time for a given battery voltage can thus be entered directly.

It can be seen from FIG. 4 that the method described here can be used not only for static operating states of the internal combustion engine, but also if its speed changes.

For this purpose, an additional control mechanism is provided, in which a special activation of the ignition coils takes place during a transition via an encoder tooth increment: If an encoder tooth increment threshold is exceeded from bottom to top, it can be determined in the control method that the ignition timing is one The ignition coil has already moved so close that the remaining charging time is no longer sufficient to achieve the required ignition energy. If a sensor tooth increment threshold is exceeded with increasing speed, the problem arises that during the lower speed a late closing event occurs in order to achieve the desired ignition energy would have been enough. Now, after the speed has increased, an earlier closing event should actually have been initiated in order to ensure a sufficient charging phase. This is no longer possible retrospectively.

In the opposite case, if the encoder tooth increment threshold is exceeded from top to bottom, no further measures are required. During the high speed, the corresponding ignition coil was closed at an earlier point in time in order to ensure the required ignition energy. Now, after the speed has been reduced, a later start of the charging phase, that is to say a later closing event, would be sufficient. In this case, a new closing event is initiated only for the ignition coil.

Finally, exceeding an encoder tooth increment threshold with increasing speed would lead to an increase in the speed range-dependent offset ILX. This means that there should be an additional segment between the ignition event and the closing event. Since such control is subsequently no longer possible, in this case, as shown above, care is taken to ensure that the ignition coil in question is positively closed at the upcoming tr mark as a compulsory measure.

These coercive measures are due to the software structure. Only the correct closing and ignition control appears to the outside. The change in the control of the ignition coils visible in a dynamic operating state of the internal combustion engine can be seen in FIG. 4. This illustration shows a dynamic transition from case B to case C.

The method can be used for any number of ignition coils, with no additional memory or RAM cell requirement in the memories being required. In particular, individual ignition coils can also be used. It should also be pointed out that this method is characterized in that z-1 ignition coils can be closed at the same time in the case of ignition coils of an internal combustion engine.

The described method can be reproduced again with the aid of FIG. 5. In this illustration, a control unit is shown which carries out the calculations described above. There are corresponding control signals to the ignition coils 1, 2, 3, 4, 5 and 6 of an internal combustion engine with six cylinders, which are only indicated here. The individual ignition coils 1, 2, 3, 4, 5 and 6 are assigned to cylinders 1 to 6.

A sensor wheel 20 is rigidly connected to the crankshaft of the internal combustion engine (not shown here), individual teeth 22 being indicated on the circumferential surface thereof, and a gap 24 can also be seen as a reference mark.

A master tooth increment, as mentioned above, is defined by the flanks of two teeth 22 immediately following one another. To clarify Such a tooth increment Z was shown in FIG. With the aid of a first sensor 26, the outer lateral surface of the sensor wheel 20 is scanned. The signals from the sensor 26 are forwarded to the control device 10 and processed by the latter.

In addition, a phase encoder wheel 40 is also shown here, which is rigidly connected to the camshaft of the internal combustion engine and has a tooth 42 on its outer surface. The phase sensor wheel 40 is scanned or the appearance of the tooth 42 is detected by a second sensor 44. The output signals of the second sensor 44 are also forwarded to the control device 10.

The ignition events of the ignition coils 1, 2, 3, 4, 5 and 6 are controlled by the control unit 10 taking into account the signals emitted by the sensors 26 and 44, as was made clear above by means of the explanation of the method.

The phase signal is only required in the case of individual ignition coils for which the method can be used in an analogous manner.

The method also allows the refined setting of the closing angle as the specified 3 ° or 6 ° without eliminating the program run benefits. In addition, the use of different ignition coils for the individual cylinders of an engine is conceivable and can be implemented using this method.

Claims

Expectations 1. A method for controlling a static ignition distribution in an internal combustion engine with a gearwheel assigned to a crankshaft and with at least two ignition coils, characterized in that the sequence of the closing and ignition events of the ignition coils can be determined as a function of encoder tooth increment thresholds Working areas. 2. The method according to claim 1, characterized gekennzeich¬ net that the selection of the controlled ignition coil in dependence on encoder tooth increments follows er¬. 3. The method according to claim 1 or 2, characterized ge indicates that at least one encoder tooth increment threshold is variable. 4. The method according to any one of the preceding Ansprü¬ che, characterized in that the Geberzahnin- be determined depending on the electrical properties of the ignition coil. 5. The method according to any one of the preceding Ansprü¬ che, characterized in that the encoder tooth increment threshold is determined as a function of the instantaneous voltage of the voltage supply. 6. The method according to any one of the preceding claims, characterized in that the closing angle is set as a function of the closing time and the speed, and that, based on an ignition event of an ignition coil, the segment associated with its closing event as a function of the encoder tooth increment threshold is determined. 7. The method according to any one of the preceding Ansprü¬ che, characterized in that ^' the position of the closing event within the segment is determined by speed, encoder tooth increment and / or Zünd¬ angle. 8. The method according to any one of the preceding Ansprü¬ che, characterized in that the closing angle is determined as a function of the closing time and the speed, and that based on an ignition event of an ignition coil whose closing event by the number of during the closing of the ignition coil capturing teeth of the gear is fixed. 9. The method according to any one of the preceding Ansprü¬ che, characterized in that the number of teeth to be detected is determined depending on the speed range. 10. The method according to any one of the preceding Ansprü¬ che, characterized in that the selection of the ignition coil to be currently controlled is carried out as a function of the change in speed during the exceeding of an encoder tooth increment threshold. 11. The method according to any one of the preceding Ansprü¬ che, characterized in that z-1 ignition coils can be closed simultaneously in an internal combustion engine with z ignition coils. 12. The method according to any one of the preceding Ansprü¬ che, characterized in that in a particularly advantageous manner the closing and ignition events over the entire speed range, in particular the areas with overlapping closing angles, with only one event counter / timer and one associated Reload value can be generated.