Combined identification of an inlet valve stroke phase difference and an outlet valve stroke phase difference of an internal combustion engine with the aid of lines of the same amplitude

Abstract

Various embodiments include a method for identifying an inlet and an outlet valve stroke phase difference comprising: measuring pressure oscillations during operation; generating a corresponding signal; determining a corresponding crankshaft phase angle; applying a discrete Fourier transformation to the pressure signal to determine amplitudes of selected frequencies in relation to the crankshaft phase angle; determining lines of equal amplitudes of the frequencies based on the amplitudes depending on the phase differences using reference lines; determining an intersection of the lines by projection into a common plane; and determining the inlet valve stroke phase difference and the outlet valve stroke phase difference from the determined common intersection point of the lines of equal amplitudes of the selected signal frequencies.

Claims

1. A method for analyzing a cylinder of a series-production internal combustion engine during operation, the method comprising: measuring dynamic pressure oscillations, associated with the cylinder, of at least one of (a) intake air in an air intake tract of the series-production internal combustion engine during operation or (b) exhaust gas in an exhaust-gas outlet tract of the series-production internal combustion engine during operation; generating a pressure oscillation signal based on the measured dynamic pressure oscillations; determining a crankshaft phase angle signal corresponding in time to the measured dynamic pressure oscillations; applying a discrete Fourier transformation to the pressure oscillation signal so as to determine amplitudes of a plurality of signal frequencies of the measured dynamic pressure oscillations in relation to the crankshaft phase angle signal; determining at least two respective constant-amplitude lines corresponding to at least two signal frequencies of the plurality of signal frequencies using stored reference line data or stored algebraic functions, wherein each of the at least two constant-amplitude lines are of equal amplitude; projecting the at least two constant-amplitude lines onto a common plane and determining an intersection point of the at least two projected constant-amplitude lines; and determining an inlet valve stroke phase difference and an outlet valve stroke phase difference of the cylinder based on the determined intersection point; and adjusting at least one control parameter of the series-production internal combustion engine based on the determined inlet valve stroke phase difference and outlet valve stroke difference.

2. The method as claimed in claim 1, further comprising: measuring dynamic pressure oscillations, associated with a reference cylinder, of at least one of (a) intake air in a reference air intake tract of a reference internal combustion engine or (b) exhaust gas in an exhaust-gas outlet tract of the reference internal combustion engine so as to determine respective reference constant-amplitude lines corresponding to a plurality of reference signal frequencies of a pressure oscillation signal generated based on the measured dynamic pressure oscillations as a function of reference inlet valve stroke phase difference values and reference outlet valve stroke phase difference values; and storing the reference constant-amplitude lines in reference line characteristic maps.

3. The method as claimed in claim 2, wherein the reference line characteristic maps are stored in a memory area of an engine control unit of the series-production internal combustion engine.

4. The method as claimed in claim 2, further comprising deriving an algebraic function from the reference line characteristic maps, which algebraic function represents a profile of the reference constant-amplitude lines, as a function of the reference inlet valve stroke phase difference values and the reference outlet valve stroke phase difference values.

5. The method as claimed in claim 4, wherein the derived algebraic function is stored in a memory area of an engine control unit of the series-production internal combustion engine.

6. The method as claimed in claim 1, wherein the projecting of the at least two constant-amplitude lines and the determining of the intersection point are performed based on the stored algebraic functions.

7. The method as claimed in claim 1, wherein the method is executed on an electronic programmable engine control unit of the series-production internal combustion engine.

8. The method as claimed in claim 7, wherein the engine control unit executes a correction to the inlet valve stroke phase difference and the outlet valve stroke phase difference.

9. The method as claimed in claim 1, wherein the plurality of signal frequencies include a first signal frequency and multiples of the first signal frequency.

10. The method as claimed in claim 1, wherein the dynamic pressure oscillations are measured by a series-production-type pressure sensor.

11. The method as claimed in claim 1, wherein the crankshaft phase angle signal is determined using a toothed gear connected to the crankshaft, and a Hall sensor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) A detailed consideration of the relationships taught herein is presented below, with reference to the figures. In the figures:

(2) FIG. 1 shows a simplified schematic drawing of a reciprocating-piston internal combustion engine;

(3) FIG. 2 shows the schematic diagram as per FIG. 1, with labelling of the possible position and angle deviations of significant components of the reciprocating-piston internal combustion engine;

(4) FIG. 3 shows two three-dimensional diagrams for illustrating the dependency of the amplitude (Amp SF) of two selected signal frequencies X and Y of the pressure oscillation signal measured in the air intake tract and/or exhaust-gas outlet tract on the inlet camshaft angle difference and the outlet camshaft angle difference;

(5) FIG. 4 shows two two-dimensional diagrams for illustrating lines of equal amplitude for two selected signal frequencies X and Y of the pressure oscillation signal measured in the air intake tract and/or exhaust-gas outlet tract, projected into a plane spanned by the inlet camshaft angle difference and the outlet camshaft angle difference;

(6) FIG. 5 shows a two-dimensional diagram as per FIG. 4 with plotted lines of equal amplitude of different signal frequencies for a particular combination of inlet camshaft angle difference and of the outlet camshaft angle difference;

(7) FIG. 6 shows a simplified block diagram for illustrating an example method incorporating the teachings herein.

DETAILED DESCRIPTION

(8) When varying the inlet valve stroke phase difference EVH and the outlet valve stroke phase difference AVH on an ideal reference internal combustion engine and analyzing the pressure oscillation signal of the intake air in the air intake tract or of the exhaust gas in the exhaust-gas outlet tract, hereinafter referred to for short as pressure oscillation signal, by means of discrete Fourier analysis, and taking into consideration individual selected signal frequencies which corresponded in each case to the intake frequency or to a multiple of the intake frequency, it has been found that, in particular, the amplitudes of the individual selected signal frequencies, that is to say the amplitude level of the pressure oscillation signal in relation to a midline and the crankshaft phase angle signal, are dependent on the inlet valve stroke phase difference EVH and on the outlet valve stroke phase difference AVH.

(9) In some embodiments of a method for the combined identification of an inlet valve stroke phase difference and of an outlet valve stroke phase difference of a cylinder of a series-production internal combustion engine during operation, dynamic pressure oscillations, assignable to the respective cylinder, of the intake air in the air intake tract and/or of the exhaust gas in the exhaust-gas outlet tract of the respective series-production internal combustion engine are measured during operation and a corresponding pressure oscillation signal is generated in each case from these. At the same time, a crankshaft phase angle signal is determined. From the pressure oscillation signal, using discrete Fourier transformation, the amplitudes of selected signal frequencies of the measured pressure oscillations in relation to the crankshaft phase angle signal are determined.

(10) In some embodiments, the method includes one or more of the following: On the basis of the determined amplitudes of the respective selected signal frequencies, lines of equal amplitude of the selected signal frequencies, which lines are dependent on inlet valve stroke phase difference and outlet valve stroke phase difference, are determined. This is performed using reference lines of equal amplitude, which reference lines are stored in reference line characteristic maps or determined by means of a respective algebraic model function; A common intersection point of the determined lines of equal amplitude of the selected signal frequencies is determined by projection into a common plane spanned by inlet valve stroke phase difference and outlet valve stroke phase difference; and The inlet valve stroke phase difference and the outlet valve stroke phase difference are determined from the determined common intersection point of the lines of equal amplitude of the selected signal frequencies.

(11) A person skilled in the art will recognize all components that serve for the supply of air to the respective combustion chambers of the cylinders, and which thus define the so-called air path, may be referred to as an air intake tract or also simply intake tract, intake system, or inlet tract of an internal combustion engine. These may include for example an air filter, an intake pipe, intake manifold or distributor pipe or, for short, suction pipe, a throttle flap valve, and possibly a compressor and the intake opening in the cylinder or the inlet duct of the cylinder.

(12) By contrast, the expression exhaust-gas outlet tract or, for short, exhaust-gas tract or outlet tract of the internal combustion engine characterizes those components which serve for the controlled discharge of the exhaust gas that emerges from the combustion chambers after the combustion.

(13) For the analysis of the pressure oscillation signal, the latter is subjected to a discrete Fourier transformation (DFT). For this purpose, an algorithm known as a fast Fourier transformation (FFT) may be used for the efficient calculation of the DFT. By means of DFT, the pressure oscillation signal is now broken down into individual signal frequencies which can thereafter be separately analyzed in simplified fashion with regard to their amplitude and the phase position. In some embodiments, the amplitude of selected signal frequencies of the pressure oscillation signal are dependent on the valve control timings, relative to the crankshaft angle, of the internal combustion engine. The amplitude of a signal frequency in this case characterizes the relative amplitude level of the signal frequency signal in relation to a midline.

(14) In some embodiments, without additional sensors, the phase positions, that is to say the present stroke positions of the inlet valves and of the outlet valves of the internal combustion engine, can be determined in relation to the crankshaft phase angle and with high accuracy and can thus be used for the accurate calculation of the charge exchange process and for the tuning of the control parameters of the internal combustion engine.

(15) In some embodiments, the steps, which precede the above-described method according to the invention, of performing measurement on a reference internal combustion engine in order to determine reference lines of equal amplitude of selected signal frequencies of the pressure oscillation signal of the intake air in the air intake tract and/or of the exhaust gas in the exhaust-gas outlet tract in a manner dependent on reference inlet valve stroke phase difference and reference outlet valve stroke phase difference, and storing the reference lines of equal amplitude of the selected signal frequencies of the pressure oscillation signal in a manner dependent on reference inlet valve stroke phase difference and reference outlet valve stroke phase difference in reference line characteristic maps. In this way, the determination of the inlet valve stroke phase difference and the outlet valve stroke phase difference can be performed in a simple manner.

(16) The abovementioned reference line characteristic maps may be stored in a memory area of an existing engine control unit of the respective series-production internal combustion engine, and thus immediately available for use in the abovementioned method during the operation of the series-production internal combustion engine, without the need for separate memory means. In some embodiments, from the reference line characteristic maps, determined as described above, of the selected signal frequencies of the pressure oscillation signal, the respective signal frequency, for an algebraic model function may be derived which replicates the profile of the respective reference lines of equal amplitude of the selected signal frequencies of the pressure oscillation signal in a manner dependent on reference inlet valve stroke phase difference and reference outlet valve stroke phase difference. In this way, a mathematical formulation of the reference lines of equal amplitude is made available, which can be used during the further method for the analytical determination of the common intersection point of the lines of equal amplitude and thus for the identification of the inlet valve stroke phase difference and of the outlet valve stroke phase difference.

(17) In some embodiments, the algebraic model functions, determined as described above, for the selected signal frequencies may be stored in a memory area of an engine control unit of the respective series-production internal combustion engine. In this way, the algebraic model functions are immediately available in the controller and can be easily used for the respectively current determination of the lines of equal amplitude. It is thus not necessary to store corresponding reference line characteristic maps in the memory, which comprise large quantities of data and thus give rise to an increased memory space requirement.

(18) In some embodiments, the projection of the determined lines of equal amplitude into a common plane spanned by inlet valve stroke phase difference and outlet valve stroke phase difference in order to determine a common intersection point, are performed on the basis of corresponding algebraic functions. For this purpose, the diagrammatic illustrations used in this patent application for an improved illustration of the method are converted into algebraic functions or processing operations. This is particularly advantageous in the case of the method being executed by means of an electronic, programmable processing unit, such as for example a corresponding engine control unit (CPU), on which the corresponding processing operations can be executed. Under the abovementioned assumption, the methods described herein can be executed on an electronic, programmable engine control unit of the respective series-production internal combustion engine. In some embodiments, no separate control or processing unit is necessary, and the algorithms of the method can be incorporated into the corresponding sequences of the engine control programs.

(19) In some embodiments, an adaptation of control variables or control routines, for example the fuel mass for injection, the start time of the injection, the ignition time, the actuation of the phase adjusters of the camshafts, etc., in the context of a correction of or adaptation to the determined inlet valve stroke phase difference and the determined outlet valve stroke phase difference is performed in the engine controller. It is thus possible for the combustion process to be optimized for the real conditions of the respective series-production internal combustion engine, and thus for the fuel demand and the emissions values to be reduced.

(20) In some embodiments, the selected signal frequencies advantageously correspond to the intake frequency as fundamental frequency or 1st harmonic and the further multiples, that is to say the 2nd to Xth of the so-called harmonics of the intake frequency of the internal combustion engine. In some embodiments, the intake frequency in turn uniquely relates to the rotational speed of the internal combustion engine. Then, for said selected signal frequencies, taking into consideration the crankshaft phase angle signal detected in parallel, the amplitude of the selected signal frequencies is determined in relation to the crankshaft phase angle. This yields particularly unique results, which are thus easy to evaluate, in the determination of the lines of equal amplitude, which thus results in high accuracy of the results.

(21) In some embodiments, the dynamic pressure oscillations of the intake air in the air intake tract to be measured by means of a series-production-type pressure sensor, which is already provided in any case, in the intake pipe. This has the advantage that no additional sensor has to be provided for this purpose, and therefore no additional costs are incurred for executing the method according to the invention. The crankshaft phase angle signal required for the execution of the methods described herein can be determined by means of a toothed gear connected to the crankshaft and by means of a Hall sensor. Such a sensor arrangement is likewise already provided in modern internal combustion engines for other purposes. The crankshaft phase angle signal generated by means of said sensor arrangement can be easily jointly utilized by the method according to the invention. This has the advantage that no additional sensor has to be provided, and therefore no additional costs are incurred for executing the methods described herein.

(22) FIG. 3 illustrates this dependency for two different signal frequencies, the intake frequency, signal frequency X, and the first harmonic, signal frequency Y. For the variation of the inlet valve stroke phase difference EVH and of the outlet valve stroke phase difference AVH, a respective phase adjuster was used for this purpose to vary the inlet camshaft angle difference ENW and the outlet camshaft angle difference ANW in the range between 5 and +5, and the respectively associated amplitude of the respective signal frequency Amp_SF of the pressure oscillation signal was plotted vertically above the ENW-ANW plane thus spanned.

(23) Under ideal circumstances, there is a direct and unique relationship between inlet camshaft angle difference ENW and inlet valve stroke phase difference EVH and between outlet camshaft angle difference ANW and outlet valve stroke phase difference AVH. For every selected signal frequency, there is thus a resulting, differently inclined amplitude surface 100, 200 in the spanned three-dimensional space. If section planes 110, 120, 210, 220 lying parallel to the ENW-ANW plane are now laid at the level of different amplitudes Amp_SF of the respective signal frequency, one obtains respective lines of intersection with the respective amplitude surface 100, 200, which lines can be referred to as lines of equal amplitude. That is to say, for all ENW-ANW combinations lying along such a line of equal amplitude, one obtains the same amplitude of the selected frequency of the pressure oscillation signal. Conversely, this means that a determined amplitude of a signal frequency of the pressure oscillation signal cannot be assigned a unique ENW-ANW combination.

(24) FIG. 3 shows, in the case of signal frequency X, the phase surface 100 and, by way of example, two section planes 110, 120 at amplitude 0.165 and 0.160. The line of equal amplitude 111 is obtained for amplitude 0.165, and the line of equal amplitude 121 is obtained for amplitude 0.160. In the case of signal frequency Y, the phase surface 200 and, by way of example, two section planes 210, 220 at amplitude 0.165 and 0.160 respectively are shown. The line of equal amplitude 211 is obtained for amplitude 0.165, and the line of equal amplitude 221 is obtained for amplitude 0.160.

(25) For the further examination of the relationships, the lines of equal amplitude of each selected signal frequency of the pressure oscillation signal have now been projected into the ENW-ANW plane. This is illustrated separately for signal frequency X and signal frequency Y in FIG. 4, analogously to FIG. 3. The corresponding lines of equal amplitude 111, 121 for signal frequency X and also 211, 221 for signal frequency Y have been denoted by corresponding reference designations in this illustration too. It can be seen that the lines of equal amplitude of the different selected signal frequencies have different gradients. If one projects the lines of equal amplitude of the different selected signal frequencies into the ENW-ANW plane one above the other, as illustrated in FIG. 5 on the basis of lines of equal amplitude 121 and 221, it can be seen that the lines of equal amplitude of the different signal frequencies X and Y intersect at exactly one intersection point 300 which thus represents a single ENW-ANW combination. Since, taking an ideal reference engine as a basis, a direct and uninfluenced interaction of the inlet camshaft 23 with the inlet valves 22 and of the outlet camshaft 33 with the outlet valves 32 can be assumed, i.e. a direct and unique relationship exists, an inlet camshaft angle difference ENW can be assigned a specific inlet valve stroke phase difference EVH, and the outlet camshaft angle difference ANW can be assigned a specific outlet valve stroke phase difference AVH.

(26) Thus, if one assumes otherwise ideal relationships, then it is thus possible, by determining the amplitude of at least two selected signal frequencies of the pressure oscillation signal, and taking into consideration and superposing the known lines of equal amplitude of the determined amplitudes of the respective signal frequency by projection into a common EVH-AVH plane, to determine the single intersection point of the lines of equal amplitude, and from this to determine the value of the inlet valve stroke phase difference EVH and of the outlet valve stroke phase difference AVH. In the example illustrated in FIG. 5, it is thus possible, along the arrows plotted using dashed lines proceeding from the intersection point 300, to determine an outlet camshaft angle difference ANW of 2 and an inlet camshaft angle difference ENW of 0.

(27) The relationships graphically illustrated in FIGS. 3 to 5 serve for ease of understanding of the principles of the methods described herein. Said relationships may also be represented on the basis of corresponding algebraic formulations, and the method may be executed on this basis by means of corresponding processing operations and program algorithms for example on a programmable digital control unit. For this purpose, mathematical-physical model functions corresponding for example to the illustration of the lines of equal amplitude are derived, which model functions can be used for the determination of the common intersection point.

(28) The methods for the combined identification of an inlet valve stroke phase difference EVH and of an outlet valve stroke phase difference AVH of an internal combustion engine during operation is based on the realizations presented above, and is accordingly presented, in one example, as follows:

(29) During the operation of the internal combustion engine, the dynamic pressure oscillations of the intake air in the air intake tract or of the exhaust gas in the exhaust-gas outlet tract, or else in both regions, are measured continuously. The respective measurement results in a pressure oscillation signal. At the same time, a crankshaft phase angle signal is detected by sensor means. The pressure oscillation signal and the crankshaft phase angle signal are supplied to a control unit 50 of the internal combustion engine 1 via corresponding signal inputs 51. In the control unit 50, the pressure oscillation signal is subjected, by means of program algorithms stored therein, to a discrete Fourier transformation, and the respective amplitude of selected signal frequencies, preferably of the first and further harmonics of the intake frequency of the internal combustion engine, of the measured pressure oscillations in relation to the crankshaft phase angle signal is determined.

(30) Subsequently, for the individual selected signal frequencies, on the basis of the respective amplitude, in each case one corresponding line of equal amplitude is determined. This is performed in each case either by selection of a reference line of equal amplitude from a reference line characteristic map which is typical for the corresponding internal combustion engine series and which is stored in a memory area of the control unit 50, or by calculation by means of a respective algebraic model function, which is typical for the corresponding internal combustion engine series and which is stored in a memory area of the control unit, and corresponding processing operations and program algorithms.

(31) The thus determined lines of equal amplitude of the individual selected signal frequencies are then, by means of corresponding program algorithms stored in the control unit, projected into a common plane spanned by inlet valve stroke phase difference EVH and outlet valve stroke phase difference AVH, and thus brought to a common intersection point. From the position of said common intersection point in the plane spanned by inlet valve stroke phase difference EVH and outlet valve stroke phase difference AVH, it is then possible to determine the inlet valve stroke phase difference EVH and outlet valve stroke phase difference AVH.

(32) For the execution of the method, specific characteristic maps with reference lines of equal amplitude or corresponding algebraic model functions may be used. These are dependent on the type of construction and the detailed structural design of the type series/series of an internal combustion engine and may therefore be determined on a structurally identical reference internal combustion engine that is typical of the series. For this purpose, on the reference internal combustion engine, the pressure oscillation signal in the air intake tract and/or in the exhaust-gas outlet tract is recorded at the greatest possible number of operating points, with variation of the inlet valve stroke phase difference EVH and of the outlet valve stroke phase difference AVH, and is subjected to a discrete Fourier transformation, and the amplitudes for the selected signal frequencies are stored in a manner dependent on the inlet valve stroke phase difference EVH and on the outlet valve stroke phase difference AVH. It must be ensured here that no piston stroke phase difference KH is superposed on and falsifies the results.

(33) On the basis of these three-dimensional data maps thus determined, it is then possible, for the individual selected signal frequencies, for the lines of equal amplitude to be determined and stored in corresponding characteristic maps, or for the algebraic model functions for the calculation of the lines of equal amplitude to be determined. The characteristic maps and/or model functions thus determined are then stored in a memory area of a control unit of every structurally identical series-production internal combustion engine and can be used for executing the methods described herein.

(34) FIG. 6 illustrates an example embodiment of a method incorporating the teachings herein for the combined identification of an inlet valve stroke phase difference EVH and of an outlet valve stroke phase difference AVH of a cylinder of a series-production internal combustion engine 1 during operation, once again in the form of a simplified block diagram showing the major steps. At the start, dynamic pressure oscillations, assignable to the respective cylinder, of the intake air in the air intake tract and/or of the exhaust gas in the exhaust-gas outlet tract of the respective series-production internal combustion engine are measured during operation and a corresponding pressure oscillation signal is generated from these, and a crankshaft phase angle signal is determined at the same time, as illustrated by the blocks which are arranged in parallel and which are labelled DDS (dynamic pressure oscillation signal) and KwPw (crankshaft phase angle). Then, from the pressure oscillation signal (DDS), using discrete Fourier transformation (DFT), the amplitude of multiple selected signal frequencies (Amp_SF_1 . . . Amp_SF_X) of the measured pressure oscillations in relation to the crankshaft phase angle signal (KwPw) are determined, which is illustrated by means of the blocks labelled DFT (discrete Fourier transformation) and Am_SF_1 to Amp_SF_X (amplitude of the respective signal frequency).

(35) Then, on the basis of the determined amplitudes (Amp_SF_1 . . . Amp_SF_X) of the respective selected signal frequency, in each case one line of equal amplitude L_Amp_1 . . . L_Amp_X of the respectively same signal frequency, which line is dependent on inlet valve stroke phase difference and outlet valve stroke phase difference, is determined, as illustrated by means of the correspondingly labelled blocks. This is performed using reference lines of equal amplitude RL-Amp_1 . . . X of the respective signal frequency, which reference lines are stored in reference line characteristic maps or determined by means of a respective algebraic model function. For this purpose, in the diagram in FIG. 6, a memory labelled Sp_RL/Rf is illustrated, from which the reference lines of equal amplitude RL_Amp_1 . . . X, or else corresponding algebraic model functions Rf(Amp_1 . . . X), provided therein can be accessed for the purposes of determining said lines.

(36) Subsequently, one respective common intersection point of the determined lines of equal amplitude L_Amp_1 . . . L_Amp_X is then determined by projection into a common plane spanned by inlet valve stroke phase difference and outlet valve stroke phase difference, as illustrated by the block labelled SPEm (intersection point determination).

(37) Finally, from the determined intersection point of the lines of equal amplitude L_Amp_1 . . . L_Amp_X of the selected signal frequencies, the inlet valve stroke phase difference EVH and the outlet valve stroke phase difference AVH are determined. This is illustrated by the blocks correspondingly labelled in FIG. 6.

(38) Furthermore, FIG. 6 shows the steps, which precede the above-described method, of performing measurement on a reference internal combustion engine in order to determine reference lines of equal amplitudes RL_Amp_1 . . . X of selected signal frequencies of the pressure oscillation signal in the air intake tract and/or of the exhaust gas in the exhaust-gas outlet tract in a manner dependent on reference inlet valve stroke phase difference and reference outlet valve stroke phase difference, and storing the reference lines of equal amplitudes of the selected signal frequencies of the pressure oscillation signal in each case in a manner dependent on reference inlet valve stroke phase difference and reference outlet valve stroke phase difference in reference line characteristic maps, as is symbolically illustrated by the block labelled RL_Amp_1 . . . X.

(39) The block labelled Rf(Amp_1 . . . x) comprises the derivation of algebraic model functions which, as reference line functions of equal amplitude Rf(Amp_1) . . . Rf(Amp_X), replicate the profile of the respective reference lines of equal amplitude of the selected signal frequencies of the pressure oscillation signal in a manner dependent on the reference inlet valve stroke phase difference and reference outlet valve stroke phase difference, on the basis of the previously determined reference line characteristic maps.

(40) The reference line characteristic maps or reference line functions of equal amplitude are then stored in a memory area Sp_RL/Rf of an engine control unit 50, CPU of the respective series-production internal combustion engine, where they are available for the execution of the method according to the invention as discussed above. The border shown by dashed lines around the corresponding blocks in the block diagram symbolically represents the boundary between an electronic programmable engine control unit 50, CPU of the respective series-production internal combustion engine, on which the method is executed.