Method for operating an internal combustion engine and corresponding arrangement

Abstract

A method for operating an internal combustion engine and a corresponding device are described, reference pulses (45) being generated synchronously with respect to the cyclical movement of at least one part of the internal combustion engine. At least one event moment for the occurrence of at least one event is calculated by an output unit (24) at specific, definitively preset time intervals of the cyclical movement. Moreover, an independent clock-pulse generator (25) is provided which generates clock pulses, the interval of the clock pulses being independent of the movement, and the interval of the clock pulses being smaller than the intervals of the reference pulses. The at least one event moment is expressed as the number of clock pulses of the independent clock-pulse generator, and the at least one event is triggered upon reaching the number of clock pulses. By observing the clock pulses of the independent clock-pulse generator (25) counted between at least two successive reference pulses, a relationship value is formed which contains information about the future timing of the movement, this relationship value being used to alter the number of clock pulses.

Description

BACKGROUND INFORMATION

[0001] The present invention relates to a method for operating an internal combustion engine, as well as to a corresponding device. The German Patent Application 199 12 770.0 has already described a method and a corresponding device for operating an internal combustion engine, the setpoint value for the dwell period of a controllable switch of an ignition device being expressed as the number of clock pulses of a clock-pulse generator, the clock pulses being generated independently of the movement of the crankshaft. The ignition is triggered after reaching the calculated number of clock pulses.

[0002] Furthermore, from the German Patent Application 199 06 390.7, a method and a corresponding device are known for operating an internal combustion engine, differentiation being made between two output modes. First of all, in the ignition-angle output mode, the moment of ignition is output in such a way that the calculated ignition angle is honored. Secondly, in the charging-time output mode, an ignition is triggered when a specific charging time of the ignition coil has elapsed.

SUMMARY OF THE INVENTION

[0003] In contrast, the method of the present invention and the corresponding device according to the invention having the features of the independent claims have the advantage that after calculating the setpoint values, the dynamics of the internal combustion engine are taken into consideration, as well. It is thereby possible to operate the internal combustion engine closer to time happenings, and thus to avoid errors developing due to the dynamics. Moreover, it is always ensured that, for example, even if a trigger wheel sensor malfunctions, at least the events associated with the setpoint values already calculated are output in any case.

[0004] The measures set forth in the dependent claims permit advantageous further developments and improvements of the method specified in the independent claim or of the device specified in the independent claim. It is particularly advantageous to initialize the pulse counter after each reference pulse, since the adaptation to a new dynamic of the internal combustion engine may thus take place in the simplest manner. Moreover, it is advantageous to calculate event moments in a cylinder-individual manner, since the cylinders can have different properties. An independent calculation of setpoint values as a function of operating parameters and operating modes with the aid of a control unit separate from an output unit is advantageous, since the computing capacity of the ECU (electronic control unit) is thereby sensibly utilized. For an optimal realization of the ignitions of an internal combustion engine, it is advantageous, first of all, to calculate a moment at which the controllable switch is closed, and a moment of ignition or a dwell-period duration, or in the case of a pulse pull-ignition, to use the number of sparks in a spark band, a recharge time or a break time as setpoint values. To achieve a proper allocation of the processes in the internal combustion engine timewise, it is advantageous to relay the setpoint values in their time sequence to the output unit. Thus, it is possible to recognize long dwell periods early and output them reliably. It is furthermore advantageous to design the events to be controlled in the internal combustion engine as a function of operating parameters, since it is thus possible to image the state of the internal combustion engine as precisely as possible. Moreover, the differentiation of various operating modes is also a possibility, to represent different states of the internal combustion engine as accurately as possible. A further embodiment form, in which the operating mode is held constant over at least two segments, is advantageous, since disadvantageous transitions from one operating mode to the next are thereby avoided. If the number of clock pulses which should pass by until a specific event is very small or negative, then the speed of the control is not sufficient to trigger the event in time. Therefore, it is advantageous that the calculated number of clock pulses is not altered in this case. In order to be able to observe the dynamics of the internal combustion engine long in advance, or to be able to ensure long dwell periods, it is necessary that the event moments for a specific number of cylinders be calculated in a cylinder-individual manner.

[0005] According to a further advantageous refinement of the invention, provision is made in the output unit for storage units whose contents are dependent on the triggering of the events. It is particularly advantageous to provide a success-bit storage location which has a first value when an event has ended, and has a second value when the event has been calculated once more in a new cycle. It is thereby possible to monitor the successful completion of the process of the internal combustion engine, and to forestall false triggerings as long as no new value has yet been calculated for a new cycle. It is also possible to monitor that a new setpoint value is not calculated as long as the event has not been triggered. Equally advantageous is the introduction of an activity-bit storage location which has a first value when the beginning of an event has been triggered, and has a second value when the end of the event has been reached. Based on this activity bit, it is possible to monitor that no new setpoint values are loaded and calculated during the course of the event. For certain processes in the internal combustion engine, it is also advantageous to determine, with the aid of the activity bit, how long an event lasts and/or how many cylinders are performing this event simultaneously. In this context, it is advantageous that in response to an overly long duration of an event, e.g., a charging of an ignition coil is lasting too long, a disturbance is recognized and this event is triggered, i.e., the charging of the ignition coil is ended.

BRIEF DESCRIPTION OF THE DRAWING

[0006] Exemplary embodiments of the invention are shown in the drawings and are explained in greater detail in the following description.

[0007] FIG. 1 shows a device of the present invention for operating an internal combustion engine; and

[0008] FIG. 2 shows a schematic representation of the time sequence of the reference pulses, signals and values, present in the internal combustion engine, which are available in the storage unit of the output unit of the device according to the present invention for operating the internal combustion engine.

DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

[0009] FIG. 1 shows schematically a device of the present invention for controlling an internal combustion engine, particularly for igniting an internal combustion engine. The device in FIG. 1 has an ignition coil which includes a primary coil 3 and a secondary coil 4. Primary coil 3 is connected at its one end to a battery voltage terminal 9. The other end of primary coil 3 is connected to an ignition driver stage 5 which contains a controllable switch, preferably a transistor. Furthermore, the other end of primary coil 3 is connected to the one end of secondary coil 4. The other end of secondary coil 4 is connected to a first electrode of a spark plug 7. The second electrode of spark plug 7 is connected to ground. Ignition driver stage 5 is also connected to ground. Ignition driver stage 5 has a controllable input 11 that is connected to ECU 20, ECU 20 transmitting to controllable input 11, signals which lead to the triggering of the ignition. For example, in response to the transmission of a first signal from ECU 20 to controllable input 11 of ignition driver stage 5, the controllable switch is closed and a current flows through primary coil 3. If ECU 20 transmits a second signal, then the controllable switch is opened again, and the flow of current through primary coil 3 is interrupted. The result is that in secondary coil 4, a voltage is induced which generates an ignition spark in spark plug 7.

[0010] In one preferred exemplary embodiment, ECU 20 has a control unit 22 and an output unit 24 which exchange data via connections 26 and 28. Output unit 24 is connected directly to input 11 of controllable switch 5. Signals may be relayed via this connection from output unit 24 to driver stage 5. The internal combustion engine preferably also has at its crankshaft, a toothed wheel having a defined number of teeth. A trigger wheel sensor 32 detects the occurrence of gaps between the teeth of the trigger wheel, and relays a signal via connection 34 to output unit 24 when a tooth gap has been detected by trigger wheel sensor 32. Analogous thereto, a pulse is likewise relayed to control unit 22 via connection 35 when a tooth gap has been detected by trigger wheel sensor 32. Furthermore, the internal combustion engine has sensors 36 which monitor various operating parameters of the internal combustion engine. For the sake of simplicity, the plurality of sensors is represented here by a small box 36. Operating parameters which are monitored by sensors 36 are, for example, the temperature of the outside air, the coolant temperature, the temperature in the intake tract, the position of the throttle valve, the presence of an exhaust-gas recirculation, a knock control, the load state and/or the engine speed. The information about the operating parameters ascertained by sensors 36 is relayed via connection 38 to control unit 22. Output unit 24 contains an independent clock-pulse generator 25 which generates pulses independently of the processes in the internal combustion engine, i.e., independently of the movements proceeding in the internal combustion engine. Furthermore, output unit 24 has a pulse counter 27 which counts pulses of independent clock-pulse generator 25. Output unit 24 also contains a storage unit 29 in which values may be stored. All the components of the output unit are interconnected and are able to exchange and/or retrieve data.

[0011] The method of the present invention for operating an internal combustion engine is now explained with reference to FIG. 2. All signal sequences plotted over the X-axis in FIG. 2 are time-dependent, i.e., the time is plotted on the X-axis. Pulse sequence 40 is a pulse sequence as trigger wheel sensor 32 relays it via connections 34 and 35, respectively, to output unit 24 and control unit 22. This pulse sequence 40 contains information about what rotational angle the crankshaft is exhibiting.

[0012] At specific, definitively preset intervals, e.g. at a crank angle of 72° before top dead center of each cylinder, control unit 22 triggers by a signal 41 at a moment t1 or t7 that the data of sensors 36 are being scanned by control unit 22. According to the data of the sensors, at moments t1 and t7, respectively, control unit 22 calculates setpoint values for specific events which should take place in the future in the internal combustion engine. Such setpoint values for the event “ignition” are, for example, the crank angle at which the controllable switch of driver stage 5 is closed, the ignition angle and the time duration in which the controllable switch of driver stage 5 should be closed (dwell period). If the ignition proceeds in the form of a pulse pull-ignition, setpoint values such as the number of sparks in a spark band, the recharge angle and the break time are calculated. Moreover, for the event “injection”, setpoint values such as the injection quantity, the injection angle or the injection duration may also be calculated. These or other setpoint values for future events in the internal combustion engine, as well—other than the previously indicated events may also be taken into account in this context—are calculated by control unit 22 as a function of operating modes which are selected dependent on the information from sensors 36. Operating modes such as operation during the start phase, dynamic operation, normal operation (partial load), idling operation and/or full load operation may be differentiated. These operating modes are generally known for the operation of internal combustion engines and are therefore not further clarified here.

[0013] In a preferred specific embodiment, these setpoint values are calculated cylinder-individually, the setpoint values preferably being calculated simultaneously for a plurality of cylinders, the events proceeding in the cylinders one after the other; for example, in the case of a 4-cylinder internal combustion engine, the ignition takes place first in the first cylinder, then in the second cylinder, after that in the third cylinder and then in the fourth cylinder, etc. These setpoint values are subsequently relayed in the corresponding time sequence via connection 28 to output unit 24, the setpoint values at this point of time not yet being allocated to a specific cylinder. In FIG. 2, the delivery of the setpoint values to output unit 24 is represented schematically by tables 47 which contain setpoint values A1, A2, A3 and A4 for an event in time sequence, e.g. the ignition-angle setpoint values.

[0014] Output unit 24 now links the setpoint values to the corresponding cylinders in which the events associated with the setpoint values are to take place. Thus, to come back to the example cited above, A1 is then a setpoint value for the ignition in cylinder 1, A2 is a setpoint value for the ignition in cylinder 2, A3 is a setpoint value for the ignition in cylinder 3 and A4 is a setpoint value for the ignition in cylinder 4. After the delivery of the setpoint values to output unit 24 and the allocation to the cylinders, event moments which result from the setpoint values are calculated from the setpoint values. For example, from the setpoint value for the ignition angle of the first cylinder, a moment of ignition, i.e. a moment at which the controllable switch of ignition driver stage 5 should be opened again, is ascertained. From this, output unit 24 calculates the number of pulses which must be awaited from independent clock-pulse generator 25 from the calculation moment until the event moment. These pulses are counted by pulse counter 27, and when a comparison unit, contained in output unit 24, establishes the agreement of the number of pulses counted by pulse counter 27 with the number of calculated pulses, a signal is generated which results in output unit 24 transmitting, for example, to controllable input 11 of driver stage 5, a signal for interrupting the flow of current through the primary coil. A sequence of such signals S1 and S2 is shown in FIG. 2 by curves 52 and 62. At moment t2, a first signal is transmitted to controllable input 11 of ignition driver stage 5, so that current flows through primary coil 3; and at a moment t5, a second signal is transmitted to controllable input 11 of ignition driver stage 5, so that the flow of current through primary coil 3 is interrupted. This initiates an ignition in spark plug 7, which is indicated here by a lightning symbol. In the case of signal sequence S2 of curve 62, the flow of current through primary coil 3 begins at moment t3, and the flow of current through primary coil 3 ends at moment t10.

[0015] The setpoint values are only calculated at moments t1 and t7, respectively, i.e. at specific, definitively preset crankshaft angles. However, because of the dynamics of the internal combustion engine, between the moments of calculating the setpoint values, a change may occur in the movement of the internal combustion engine compared to the previously calculated relationships. The intention is to take this into account in the method presented here. To that end, signal sequence 40, which is yielded from the crankshaft signal, is utilized. Each pulse, relayed from trigger wheel sensor 32 to output unit 24, is designated as reference pulse 45. At the moment of each reference pulse 45, output unit 24 ascertains the number of clock pulses of independent clock-pulse generator 25 between two previously registered reference pulses 45. From this number and a comparison of the number to one or more previously ascertained numbers of clock pulses, conclusions may be drawn about the dynamics of the internal combustion engine. Accordingly, a relationship value is calculated, so that event moments A1 through A4 and A2 through A5, respectively, calculated at moments t1 and t7, respectively, are in each case adapted according to this change. To then obtain a correct comparison between the calculated number of clock pulses and the clock pulses of independent clock-pulse generator 25, pulse counter 27 is re-initialized at the moment of each reference pulse 45.

[0016] In this method, it is advantageous that, even in the event of the loss or malfunction of the trigger wheel sensor, i.e., when reference pulses 45 are no longer present, events still following may be output, since independent clock-pulse generator 25, together with pulse counter 27, ensures an output of the calculated event moments, independently of the trigger wheel sensor.

[0017] Alternatively, the method may also be carried out in such a way that the clock pulses are adapted, for example, at each second reference pulse 45. However, a prerequisite for the functioning of the method is that the clock pulses of independent clock-pulse generator 25 are output at markedly smaller intervals than reference pulses 45. Furthermore, reference pulses 45 have perceptibly smaller intervals than pulses 41 at which the setpoint values are calculated.

[0018] In certain situations, it may occur that the number of clock pulses calculated at a reference pulse 45 up to the occurrence of an event moment is very small, i.e., because of the dynamics, the event should already have been in the past, and thus a negative number was ascertained. This occurs, for example, when the internal combustion engine has experienced a sharp acceleration. For safety reasons, when the number of clock pulses is smaller than a specific threshold value, the value for the clock pulses is not updated and the previously calculated value is retained. Thus, at any rate, the event is triggered.

[0019] In one preferred exemplary embodiment, the output unit is able to differentiate two output modes, the ignition-angle output mode and the charge-time output mode. In the ignition-angle output mode, as described above, the number of clock pulses to be awaited until the opening of the controllable switch of ignition driver stage 5 is updated at each reference pulse 45. In the charge-time output mode, after the controllable switch of ignition driver stage 5 has been closed, i.e. the charge time has begun, the number of clock pulses to be awaited is no longer updated. This ensures that exactly the calculated dwell period is output which is needed to make an energy sufficient for the ignition available in the ignition coil. Thus, it is possible to minimize the power loss.

[0020] In the case of certain operating modes, it is necessary that the setpoint-value calculation from one moment of the setpoint-value calculation to the next moment of the setpoint-value calculation not change back and forth quickly between different operating modes. This is particularly the case for internal combustion engines which work with direct gasoline injection. Such internal combustion engines may be operated using the same method described above. Homogenous operation, homogenous/lean operation and stratified operation may be defined here as possible operating modes. These operating modes are generally known in the case of direct gasoline injection, and therefore shall not be further clarified here. To avoid disadvantageous switching back and forth between two operating modes, attention is given here when calculating the setpoint value that the setpoint-value calculation is based on the same operating mode over at least two setpoint-value calculation time intervals, which are also called segments.

[0021] In a further preferred exemplary embodiment, the device for operating an internal combustion engine includes in output unit 24, a storage unit 29 which contains values for each cylinder and for each event, the contents of the respective storage location of the corresponding cylinder being scanned prior to triggering the event, and the triggering of the event being influenced as a function of the contents of the storage location. Furthermore, the contents of the corresponding storage location may also be altered by the triggering of events.

[0022] For example, for each cylinder and each event, storage unit 29 contains a so-called success-bit storage location ignsuc1 for the first cylinder, ignsuc2 for the second cylinder. The contents of these storage locations are represented in FIG. 2 in terms of curves 54 and 64, respectively. At the beginning of the observations, storage location ignsuc1 contains the value 1. On the basis of the calculation of a new setpoint value, at moment t1, the value of this success-bit storage location is set to zero. Upon conclusion of a process, i.e., here in response to the output of the signal for the opening of the controllable switch of ignition driver stage 5 at moment t5, the success-bit storage location of the first cylinder is set to the value 1. After the calculation of a new setpoint value at moment t7, the success-bit storage location is again set to the value zero. The method may also be carried out correspondingly with complementary values, i.e., the success-bit storage location may have the value zero whenever the output of the signal for opening the controllable switch takes place, and upon calculation of a new setpoint value, may be changed to the value 1.

[0023] In the output unit, the value of this success-bit storage location may now be scanned before a new ignition process is initiated. If the success-bit storage location of the cylinder in question still contains the value 1, that is to say, the ignition was carried out and no new setpoint value has yet been loaded, then it is not plausible that a new ignition is carried out. Consequently, for this case, the closing of the controllable switch of the ignition driver stage is not implemented. This plausibility conflict is signaled to the fault management of ECU 20.

[0024] Moreover, in one preferred exemplary embodiment, storage unit 29 contains a so-called activity-bit storage location for each cylinder and each event. The values which an activity-bit storage location has for the first and the second cylinder are represented in FIG. 2 by curves 56 and 66, and are designated by ignact1 and ignact2. As long as the ignition process is not initiated, the activity-bit storage location has the value 0. If the charging of the ignition coil, i.e. the flow of current through primary coil 3 is begun, then the value 1 is allocated to the activity-bit storage location, and upon triggering of the end of the flow of current through the primary coil, the value 0 is allocated to the activity-bit storage location of the respective cylinder. Thus, during the charging of the ignition coil, the activity-bit storage location has the value 1, and otherwise the value 0. In this context, it may also be configured that the activity-bit storage location has the value 0 during the charging of the ignition coil, and otherwise the value 1.

[0025] During the charging of the ignition coil of the respective cylinder, it is not sensible that new setpoint values for the event “ignition” be loaded. Therefore, the loading of new setpoint values for moment t1 or t7 is suppressed when the activity-bit storage location has the value 1 for the cylinder in question. In a further exemplary embodiment, for the charge-time output mode, based on the value stored at the activity-bit storage location of the respective cylinder, it is deduced whether a charging of the ignition coil is taking place. For example, when the activity-bit storage location has the value 1, output unit 24 is prohibited from updating the number of clock pulses to be awaited until the opening of the controllable switch. In a further exemplary embodiment, based on the time duration over which the activity-bit storage location of a cylinder has a value 1, it is ascertained how long the charge time lasts. If the charge time exceeds a threshold value, then the charging of the ignition coil is lasting an implausibly long time, and a forced ignition is initiated. Moreover, from the contents of the activity-bit storage locations, it may be ascertained how many ignition coils are in the “charge” state simultaneously.

[0026] In a further exemplary embodiment, a diagnostic-bit storage location may also be provided in storage unit 29 for each cylinder. The value of such a diagnostic-bit storage location for a first and second cylinder, respectively, is represented in FIG. 2 in terms of curves 58 and 68. At a specific moment prior to triggering the ending of the charging of the ignition coil at moment t5, the diagnostic-bit storage location of the respective cylinder is allocated a value 1, and at a specific time after the triggering of the end of the charging of the ignition coil, the diagnostic-bit storage location is allocated a value 0. For example, for the first cylinder represented in FIG. 2, this may occur at a moment t4 and t8. For the second cylinder, the diagnostic-bit storage location is set to the value 1 at moment t9.

[0027] During the time in which the diagnostic-bit storage location has the value 1, the diagnosis, that is to say, for example, the checking of hardware and software functions for the respective cylinder is enabled. Here, values are requested of diagnostic components and are processed in ECU 20. It is thereby ensured that the diagnostic is run for the correct cylinder in each case, and thus the values applicable for the

Claims

1. A method for operating an internal combustion engine, in which a) reference pulses (45) are generated synchronously with respect to the cyclical movement of at least one part of the internal combustion engine, b) at least one event moment (t2, t3, t5, t10) for the occurrence of at least one event is calculated with the aid of an output unit (24) at specific, definitively preset intervals of the cyclical movement, c) with the aid of an independent clock-pulse generator (25) of an output unit (24), clock pulses are generated whose interval is independent of the movement, the intervals of the clock pulses being smaller than the intervals of the reference pulses (45), d) the at least one event moment (t2, t3, t5, t10) is expressed as the number of clock pulses of the independent clock-pulse generator (25), e) upon reaching the number of clock pulses by a pulse counter (27), the at least one event is triggered, wherein f) by observing the clock pulses of the independent clock-pulse generator (25) counted between at least two successive reference pulses (45), a relationship value is formed which contains information about the future time sequence of the movement, and g) the relationship value is used to alter the number of clock pulses.

2. The method as recited in claim 1, wherein the pulse counter (27) is initialized at each reference pulse (45), and using the relationship value, the number of clock pulses of the independent clock-pulse generator (25) up to the at least one event moment (t2, t3, t5, t10) is recalculated.

3. The method as recited in claim 1, wherein if there is a plurality of cylinders, the at least one event moment (t2, t3, t5, t10) is calculated cylinder-individually.

4. The method as recited in one of the preceding claims, wherein the at least one event moment (t2, t3, t5, t10) is calculated by an output unit (24) from at least one setpoint value of the internal combustion engine, the at least one setpoint value being determined by a control unit (22) as a function of at least one operating parameter and at least one operating mode with reference to characteristic curves stored in the control unit (22), the at least one setpoint value being transferred by the control unit (22) to the output unit (24).

5. The method as recited in claim 4, wherein an ignition angle, an angle at which the controllable switch (5) is closed, a dwell-period duration, a number of sparks in a spark band, a recharge angle or a break time represent setpoint values.

6. The method as recited in claim 4 or 5, wherein in the case of an internal combustion engine having a plurality of cylinders, the setpoint values are transferred to the output unit (24) in time sequence, the output unit (24), prior to calculating the event moments, allocating the setpoint values to the cylinders passing through an ignition top dead center in time sequence.

7. The method as recited in claim 4, wherein at least one temperature, among them preferably a temperature of the outside air, a coolant temperature and/or an intake temperature, as well as a position of the throttle valve, the presence of an exhaust-gas recirculation, a knock signal, a load signal and/or an engine speed are scanned as operating parameters; and as possible operating modes with reference to the moment after the start of the internal combustion engine or with reference to the engine speed or engine-speed dynamics, the following operating modes are differentiated: operation in the start phase, dynamic operation, normal operation, idling operation and/or a full-load operation; and homogeneous operation, homogeneous/lean combustion operation and stratified operation are differentiated with reference to the direct gasoline injection; the operating modes with reference to the moment after the start or with reference to the engine speed being able to be combined with the operating modes with reference to the direct gasoline injection.

8. The method as recited in claim 4, wherein the operating mode used for calculating the setpoint values is not altered over the duration of at least two specific intervals of the cyclical movement.

9. The method as recited in claim 1, wherein the movement of at least one part of the internal combustion engine is the movement of a crankshaft; and intervals of a specific, definitively preset angular position of the crankshaft before an ignition top dead center are the specific, definitively preset interval of the cyclical movement.

10. The method as recited in claim 1, wherein when the number of clock pulses calculated at the reference pulse (45) is smaller than a first threshold value, the number of clock pulses calculated in a previous step is not altered.

11. The method as recited in claim 3, wherein the at least one event moment (t2, t3, t5, t10) is calculated cylinder-individually at the specific, definitively preset intervals of the cyclical movement simultaneously for a specific, definitively preset number of cylinders.

12. The method as recited in one of the preceding claims, wherein at least one storage location in a storage unit (29) of the output unit (24) contains a first or second value for each cylinder of the internal combustion engine and for each event; the contents of the at least one storage location of the corresponding cylinder are scanned prior to triggering the at least one event for the cylinder in question, and the triggering of the at least one event is influenced as a function of the contents of the at least one storage location, and/or the contents of the at least one storage location of the corresponding cylinder are altered by the triggering of the at least one event for the respective cylinder.

13. The method as recited in one of the preceding claims, wherein the at least one event includes at least the beginning of a process and the end of a process, preferably the beginning of a dwell period and the end of a dwell period, and accordingly, the at least one event moment (t2, t3, t5, t10) includes an event beginning moment (t2, t3) and an event ending moment (t5, t10), preferably the dwell-period beginning moment and the dwell-period ending moment.

14. The method as recited in claim 13, wherein a success-bit storage location is set to a first value by the triggering of the end of the event of the corresponding cylinder and of the corresponding event; the success-bit storage location of the corresponding cylinder and of the corresponding event being set to a second value by calculating a new, at least one event moment for the respective event at the specific, definitively preset intervals.

15. The method as recited in claim 14, wherein as long as the success-bit storage location of the specific cylinder and of the specific event has a first value, the event for the specific cylinder is not triggered.

16. The method as recited in claim 13, wherein an activity-bit storage location of one cylinder and of one event is set to a first value by the triggering of the beginning of this event for this cylinder; and this activity-bit storage location is set to a second value by the triggering of the end of this event for this cylinder.

17. The method as recited in claim 16, wherein as long as the activity-bit storage location of a cylinder and of an event has a first value, no new setpoint values are calculated for this event and this cylinder.

18. The method as recited in claim 16, wherein the sum of the cylinders is ascertained whose activity-bit storage location has a first value; and/or the number of reference pulses (45) of a cylinder and/or the number of intervals of the cyclical movement is ascertained, during which the activity-bit storage location of the respective cylinder retains the first value unchanged.

19. A device for operating an internal combustion engine, a sensor unit (32) being provided by which reference pulses (45) are able to be generated synchronously with respect to the cyclical movement of at least one part of the internal combustion engine; an output unit (24) being provided by which, at specific, definitively preset intervals of the cyclical movement, at least one event moment (t2, t3, t5, t10) for the occurrence of at least one event is calculated; an independent clock-pulse generator (25) of an output unit (24) being provided by which clock pulses are able to be generated whose intervals are independent of the movement, the intervals of the clock pulses being smaller than the intervals of the reference pulses (45); with the aid of the output unit (24), the at least one event moment (t2, t3, t5, t10) being able to be expressed as the number of clock pulses of the independent clock-pulse generator (25); with the aid of the output unit (24), the at least one event being able to be triggered upon reaching the number of clock pulses by a pulse counter (27), wherein by observing the clock pulses of the independent clock-pulse generator (25) counted between at least two successive reference pulses (45), a relationship value which contains information about the future time sequence of the movement is able to be formed by the output unit (24), and the relationship value is usable by the output unit (24) in order to alter the number of clock pulses.

20. The device as recited in claim 19, wherein a pulse counter (27) is provided in such a way that it is able to be initialized at each reference pulse (45); and using the relationship value, the number of clock pulses of the independent clock-pulse generator (25) up to the at least one event moment (t2, t3, t5, t10) is able to be recalculated.

21. The device as recited in claim 19, wherein if there is a plurality of cylinders, at least one event moment (t2, t3, t5, t10) is able to be calculated cylinder-individually by the output unit (24).

22. The device as recited in one of claims 19 through 21, wherein the at least one event moment (t2, t3, t5, t10) is able to be calculated by output unit (24) from at least one setpoint value of the internal combustion engine, a control unit (22) being provided so that the at least one setpoint value is able to be determined as a function of at least one operating parameter and at least one operating mode on the basis of characteristic curves stored in the control unit (22), the at least one setpoint value being transferable from the control unit (22) to the output unit (24) via a connection (28).

23. The device as recited in claim 22, wherein at least one sensor (36) is provided by which at least one operating parameter is able to be detected; a temperature of the outside air and/or a coolant temperature and/or a temperature of the intake tract and/or a position of the throttle valve and/or the presence of an exhaust-gas recirculation and/or a knock signal and/or a load signal and/or an engine speed is preferably able to be scanned as operating parameter; the value of the at least one operating parameter being transferable from the at least one sensor (36) via a connection (38) to the control unit (22).

24. The device as recited in one of claims 19 through 23, wherein at least one storage location, which contains a first or a second value for each cylinder of the internal combustion engine and for each event, is provided in a storage unit (29) of the output unit (24); the contents of the at least one storage location of the cylinder in question being able to be scanned prior to triggering the at least one event for the respective cylinder, and the triggering of the at least one event being influenced as a function of the contents of the at least one storage location, or the contents of the at least one storage location of the cylinder in question being alterable by the triggering of the at least one event for the respective cylinder.