EP0162203B1 - Process and apparatus for adapting the operation characteristic of an actuating rod - Google Patents

Abstract

1. Claims for contracting states AT, IT Method is conjunction with a control or regulation system for the speed of an internal combustion engine in the case of idling via an electromechanical final control element, for controlling the air quantity or mass taken in by means of an adaptation of the shape of a characteristic of the continuously operating final control element of the internal combustion engine by converting the controlling variable (Qset , mset ) fed to the final control element (12, Id-ACT.) by the control or controller output into an adapted electrical manipulated variable (tau) for the final control element in which the controlling variable (Qset , mset ) is combined multiplicatively and/or by summation with at least one stored value (I1 , I2 ) influencing the offset and/or the slope of the characteristic of the final control element, the stored values representing an output signal of in each case one control loop which is activated in the event of certain operating conditions and, from a comparison of the controlling variable (Qset , mset ) with an actual measured value of the air-mass or air-quantity measuring device, generates the output signal with which at least one of the stored values (I1 , I2 ) is altered to produce a relatively slight control deviation, the value thus altered being stored at the temporal end of the particular operating condition. 1. Claims for contracting states DE, FR, GB Method is conjunction with a control or regulation system for the speed of an internal combustion engine in the case of idling via an electromechanical final control element, for controlling the air quantity or mass taken in by means of an adaptation of the shape of a characteristic of the continuously operating final control element of the internal combustion engine by converting the controlling variable (Qset , mset ) fed to the final control element (12, Id-ACT.) by the control or controller output into an adapted electrical manipulated variable (tau) for the final control element in which the controlling variable (Qset , mset ) is combined multiplicatively or by summation with at least one stored value (I1 , I2 ) influencing the offset and/or the slope of the characteristic of the final control element, the stored values representing an output signal of in each case one control loop which is activated in the event of certain operating conditions and, from a comparison of the controlling variable (Qset , mset ) with an actual measured value of the air-mass or air-quantity measuring device, generates the output signal with which at least one of the stored values (I1 , I2 ) is altered to produce a relatively slight control deviation, the value thus altered being stored at the temporal end of the particular operating condition, characterized in that an interlocking of offset and slope adaptation takes place to the effect that, after each slope adaptation, an offset adaptation (Qset = Qactual ) first of all takes place before another slope adaptation is enabled.

Description

State of the art

The invention relates to a method for controlling the amount or mass of air sucked in by adapting a characteristic curve of the continuously operating actuator of the internal combustion engine in conjunction with controlling or regulating the speed of an internal combustion engine when idling via an electromechanical actuator.

In many areas of technology, it is common to determine certain variables, values or positions by regulation or control, in that a variable, which is usually electrical and has a specific function profile, is supplied to any actuator by a controller that processes and also inputs certain signals from the controller path incorporates the result achieved by adjusting the actuator into its control behavior. If the overall design of a control or regulation then already results in disturbance or other undesirable influencing variables that are exclusively attributable to the actuator behavior, in other words that the course of the actuator not only follows the setpoint value supplied to it, then considerable deviations can occur of the set values which, depending on the time constants that occur, can lead to overshoots or that the control simply becomes too slow.

For example, to regulate the idle speed in an internal combustion engine, an idle speed controller is supplied with certain information about the current operating state of the internal combustion engine, for example pressure in the intake manifold, actual speed, a desired target speed for idling and other peripherally usable operating state information, such as throttle valve position, position of a bypass valve, on which the idle charge control system in particular attacks and / or, also instead of the pressure in the intake pipe, information about the intake air quantity or air mass.

From these variables, the idle speed controller can determine an electrical manipulated variable as a setpoint, for example an air volume _signal Q _solI or an air mass signal mSoll, and feed it to an idle actuator (LL actuator), which converts the air mass setpoint, for example, into an opening cross-section (of the valve in the bypass mentioned earlier) .

Especially with the idle charge control (LFR) of an internal combustion engine, however, special conditions must be taken into account, for example the lowest possible fuel consumption and keeping a minimum idle speed constant even with sudden load changes. Idle speed controllers are therefore known (DE-OS 3 039 435) and are designed so that deviations from a desired target speed are absorbed and kept small. However, the problem here is that speed fluctuations are ultimately reactions of the internal combustion engine to external influences and corresponding speed signals form the last link in the control chain, so that a certain amount of time inevitably elapses between an effect exerted on the internal combustion engine and the reaction of the internal combustion engine. There is therefore at least the risk of unsteady concentricity when the internal combustion engine is running extremely low, and ultimately there is the possibility that the internal combustion engine will stop if high consumers, such as air conditioning and the like, are switched on quickly. This problem is exacerbated by the behavior of the idle actuator itself, since the characteristic curve shows a considerable dependence on the respective temperature and the operating voltage of the internal combustion engine, which can also fluctuate considerably. Idle actuators usually work in the adjustment of the opening cross-section, via which the internal combustion engine is supplied with the required amount of air, as an electromagnetic converter and can in this case be designed as a winding rotary actuator (EWD) or as a magnetic part for valve actuation. When the idle actuator is cold, the actuator winding takes up a larger current at a given duty cycle; there is a larger deflection and a corresponding mismatch. Similar negative relationships result from considerable battery voltage fluctuations, as is very common in internal combustion engines. Therefore, in order to have the least possible mismatch in the actuator area, the idle actuator, in order to correctly convert the electrical manipulated variable supplied to it into the opening cross section, must be constructed in a complex manner and have a characteristic curve that is as reproducible as possible.

But even if the idle actuator responds perfectly, as far as possible, unavoidable dependencies, for example leakage air quantities flowing past the throttle valve in the idle position, remain dependent on the height. speed of the opening cross-section issued by the idle actuator u. the like

One of the objects of the present invention is therefore to provide a device for adapting an actuator characteristic curve which fulfills the condition that the actuation setpoint supplied to the actuator is substantially the same as the actual size resulting from the action of the actuator including peripheral influences on the idle speed controller with an idle speed controller characteristic curve, that the air quantity or air mass setpoint at the output of the idle speed controller is essentially the same as the air quantity or air mass supplied to or drawn by the internal combustion engine.

A procedure for solving the task is for the designated contracting states Federal Republic of Germany, Great Britain and France (DE, GB, FR) already known from the unpublished European patent application 84 108 796.8 (EP-A 136 449) with the priority of September 21, 1981. There, a method for adapting the characteristic curve of a continuously operating actuator of the internal combustion engine in connection with a control or regulation of the speed of an internal combustion engine when idling is presented via an electromechanical actuator. The control variable supplied to the actuator is corrected multiplicatively or by summation with the aid of stored values, and an adapted electrical control variable for the actuator is thus obtained. The multiplicative or summation correction of the control variable makes it possible to adapt the offset or the slope of the actuator characteristic curve to the prevailing conditions with the aid of the above-mentioned stored values. These stored values are obtained from an additional control circuit, which is activated under certain operating conditions, compares the target air quantity or mass specified by the control variable with the measured value of the air mass or quantity, and changes the stored values in the sense of a lower control deviation. The changed values are stored for further use for the correction described above.

For the contracting states Austria and Italy (AT, IT) not named in the European patent application 84108796.8, claim 1 describes the method presented above, claim 7 describes a device for carrying out such a method.

Furthermore, from GB-2 084 353 a mathematical method from the motor vehicle area is known which corrects an electrical control signal of an injection valve in its time length additively and multiplicatively. In this discontinuously operating actuator, however, the injected quantity is neither measured nor corrected, but rather a field of characteristics is corrected in the sense of an optimization of lambda = 1. The directly influenced quantity is the amount of petrol injected, while the quantity measured is lambda. Furthermore, from the target injection time signal tp, on which the multiplicative and additive correction is carried out, the correction variables are not determined by means of a target / actual comparison, but from a measurement of lambda.

The invention described in European patent application 84108796.8 considerably improves the adaptation of the actuator characteristic curve, so that better exhaust gas values can also be expected in the dynamic behavior of engines, even in the case of larger sample variations of the actuators or their aging.

Proceeding from the method according to European patent application 84 108 796.8, there is now another task to improve the functioning of the method presented above by mutually coordinating offset and slope adaptation.

This object is achieved by the features from the second part in conjunction with the features from the first part of claim 1 for the designated contracting states DE, GB and FR in such a way that a slope adaptation can only take place after a previous offset adaptation.

Advantages of the invention

The method according to the invention with the features of claim 1 and the device according to the invention with the characterizing features of the first device claim for the named states Austria and Italy have the advantage that the adaptation to the (possibly changing under certain influencing factors) characteristic of the actuator and the inclusion and, in so far, the regulation of other disturbance variables takes place in such a way that there is an effective independence from the actuator characteristic curve, so that it is no longer necessary to construct the actuator used in each case, applied to the idle charge control, i.e. the idle actuator, in a particularly complex manner . The invention makes it possible to work with simpler actuator designs, with air mass measurement being completely independent of the height at which the internal combustion engine is located and the air quantity measurement being drastically reduced as a function of height. The invention further ensures independence from the leakage air, so that engine settings are no longer required and, moreover, the inventive adaptation, which takes place during the entire control operation, does not influence the actual idle charge control.

Advantageous further developments and improvements of the invention are possible through the measures listed in the subclaims. The possibility of reducing the iteration steps and thus a faster adaptation is particularly advantageous in that, in the case of a slope adaptation, the offset integrator is also retightened according to a calculation rule, so that the rotation of the characteristic curve around the last working point of a stored air volume actual value that occurred when the throttle valve was previously opened has been saved, and not by a reference value that is further away.

The supplemented method according to the invention with the characterizing features of the main claim for the designated contracting states Federal Republic of Germany, Great Britain and France has the advantage that incorrect adaptations, which can possibly take place through a gradient adaptation that takes place several times in succession, are avoided by initially always following a gradient adaptation a successful offset adaptation must only take place before a new slope adaptation is released. Incidentally, the offset integrator always runs, so it is released, when the throttle valve is closed, the slope integrator is not running and a specified blocking time has expired. The slope integrator is only meaningfully enabled if the current actual air volume is greater than the value stored when the throttle valve is opened, plus a definable air volume.

In its application, the invention is basically suitable for adapting any actuator characteristic curves, but is used in the following for a preferred exemplary embodiment, applied to the actuator behavior in the idle charge control (LFR) for an internal combustion engine, and explains in more detail that there is also a preferred area of application for the present invention .

drawing

An embodiment of the invention is shown in the drawing and is described and explained in more detail below. 1 shows, in the form of a block diagram, an idle charge control with idle speed controller and the idle speed controller controlled by this and an intermediate characteristic adaptation block interposed in accordance with a feature of the present invention, FIG. 2 likewise predominantly in the form of a block diagram the device for characteristic curve adaptation in greater detail, and 3 in the form of a diagram, the actuator characteristic air quantity or air mass over the electrical manipulated variable _T and the effects of the adaptation according to the invention on the course of the characteristic curve.

Description of the embodiments

Before the invention is discussed in the following, it is expressly pointed out that the block diagram shown in the drawing, which specifies the invention on the basis of discrete switching stages, does not limit the invention, but in particular serves to illustrate the basic functional effects of the invention and special functional sequences in one possible form of implementation. It goes without saying that the individual modules and blocks can be constructed using analog, digital or hybrid technology, or else, in whole or in part, corresponding areas of program-controlled digital systems, for example microprocessors, microcomputers, digital or analog logic circuits and the like . can include. The description given below of the preferred exemplary embodiment of the invention is therefore to be evaluated with regard to the overall functional and time sequence, the mode of operation achieved by the blocks discussed in each case and with regard to the respective interaction of the sub-functions represented by the individual components, the references to the individual circuit blocks only for reasons of better understanding.

The following explanations relate specifically to the application example of the invention to the optimization of the idle charge control (LFR) in an internal combustion engine (Otto engine) in such a way that the target air quantity Q _target output by an idle speed controller via an actuator characteristic curve adaptation and the idle actuator in one Q _is is reacted, whereby to apply that Q _is Q ≅ _target.

In accordance with a basic idea of the present invention, the adaptation to the characteristic curve of the idle controller then present at the respective point in time and the leakage air take place according to a specific strategy which has the aim of an additive and / or multiplicative intervention in the setpoint output by the (idle speed) controller . In this way, the otherwise necessary and usual basic setting of the leakage air is eliminated with an additional bypass (also over the service life).

In Fig. 1, the idle speed controller with 10 and the actuator controlled by it via the system for adapting the characteristic curve 11 is referred to as an idle actuator with 12. In the present application, the idle actuator acts on the opening cross section in the intake manifold of an internal combustion engine 13, in particular by correspondingly enlarging or reducing a bypass cross section or by motorized adjustment of the throttle valve.

The air that ultimately contains the internal combustion engine 13 is composed of the air through the actuator or the air that the actuator passes through due to its actuation, and a leakage air residual quantity flowing, for example, via the throttle valve. The characteristic curve adaptation according to the invention in block 11 converts the _target air quantity Q _target or m _target output by idle speed controller 10 into an electrical manipulated variable r in such a way that an air quantity (or air mass) is set with idle actuator 12 which, together with the leakage air, produces the desired intake air quantity Q _is (or air mass _m) is obtained. The adaptation takes place. doing this slowly after checking the operating status. In the speed control loop shown in FIG. 1, block 11 - adaptation and adjuster - represents a proportional element with amplification 1 and thus has no influence on the stability. The control unit simulates the inverse actuator characteristic _T = _To + m - Q (see Fig. 3).

In order to carry out the characteristic curve adaptation, two integrators 11 are provided for the characteristic curve offset or the base point shift of the characteristic curve and 12 for the characteristic curve slope, the respective integrators only running if the intervention in the characteristic curve adaptation caused by them can be released by certain operating conditions; therefore, each integrator is assigned release elements, the offset integrator 11 a release element FC1 and the slope integrator 12 a release element FG2.

Accordingly, the slope integrator 12 intervenes on the setpoint output by the idle speed controller 10 in a multiplicative manner via a multiplier M with a predetermined one level multiplier factor, while the offset correction from the output of the integrator I1 takes place additively at a summation point S1.

Both integrators 11 and 12 are supplied with an air quantity difference signal ΔQ from a second summation or comparison point S2, which corresponds to the deviation of the _target size ( _target air quantity Q _target or _target air mass m _target ) from the actual value (air quantity Q _is or air mass m _is ). The data Q _ist can be derived from an air flow meter in the intake pipe or can be obtained in another known manner.

The desired relationship Q _ist = Q _Soll (or based on the air mass, which will not be repeated in the following) can therefore be achieved by changing two parameters, namely by varying the offset K1 and by varying the slope K2. In order to ensure certain initial characteristic values, the integrators 11 and 12 are each followed by summation points S3 and S4, to which initial values K10 for the offset and K20 for the slope are supplied.

It is essential that the adaptation to the current characteristic of the idle actuator and the leakage air takes place according to the following strategy:

The integrator 11 for the offset or the base point shift of the characteristic curve only runs if the throttle valve is closed for longer than a predetermined time T1 = f (n) and the engine speed n is in a certain range, namely in the idling range. Accordingly, the release element FG1 for the integrator 11 is designed such that a throttle valve signal DK and the actual value of the engine speed n are fed to it and the offset integrator 11 is only released and runs when these two conditions are met.

wodurch es möglich ist, ein Überschwingverhalten und eine entsprechende Fehlereinführung des Luftmengenmessers auszublenden, und ferner Q_Soll größer ist als der letzte Wert Q_Soll vor dem Öffnen der Drosselklappe. Das heißt, daß der momentane Adaptions-Arbeitspunkt für den Integrator 12 auf der Kennlinie über dem Adaptions-Arbeitspunkt liegen muß, der durch den Eingriff des Offset-Integrators 11 erreicht worden ist.For the intervention by the integrator 12, which affects multiplicatively a change in the characteristic curve (change in slope) and therefore has a significantly greater effect on the electrical output _manipulated variable _T as an input signal for the idle actuator, this integrator is only released if the throttle valve has a predetermined time period T2, which, for example, can be 100 ms, is closed, the following relationship applies to T2

whereby it is possible to hide overshoot behavior and a corresponding fault introduction of the air flow meter, and furthermore Q _{Soll is} greater than the last value Q _Soll before the throttle valve is opened. This means that the current adaptation operating point for the integrator 12 must lie on the characteristic curve above the adaptation operating point that was achieved by the intervention of the offset integrator 11.

If one considers the course of the actuator characteristic curve Q = f (τ) shown in FIG. 3, which is dependent on the battery voltage, the weighting temperature, differential pressure, leakage air and the like. depends, the hatched curve curve on the left in the drawing plane is only given for the sake of completeness for an idle actuator and is not influenced as an emergency running characteristic by the measures according to the invention, then at man the model characteristic in the initial state can be seen, at @ the characteristic after adaptation offset and with @ after slope adaptation: identical to the actual actuator characteristic. As a first adaptation step, the operating point is then shifted by offset, as indicated by arrow A, it is obvious that the second step of the multiplicative gradient intervention (arrow B) must not be carried out in a working point which is below the offset working point, since in this case, the result is the reverse, that is to say the undesired effect. The slope adaptation always takes place in working points above the offset working point.

Accordingly, the conditions for the release block FG2 of the slope integrator 12 are additionally designed such that the slope is only adapted for air flow rates that are greater than, for example, a minimum air flow rate, such as results for the clear idle case.

To obtain these conditions, the procedure is preferably such that the instantaneous Q _target or m _target values are stored at the moment the throttle valve is opened, for which purpose a memory block SB is provided, to which a throttle valve signal DK and the Q _target value are supplied; this storage then corresponds to the latter operating point, at which the offset integrator 11 has adapted. To enable the slope adaptation, it is then checked in each case whether the now requested air volume value (Q _target ; m _target ) is greater than the value last saved and only then can the release be carried out; the block comparing the two setpoints is designated VG in FIG. 2.

This condition can alternatively be replaced by the consideration that a slope adaptation can always be enabled when the current speed is above a certain speed, for example the following condition is met n> n _LL + 500 min ^-1 because assumed can be that at higher speed, an operating point is taken on the characteristic that is above the idle point, so that you are on the correct section of the characteristic. Such a case of increased speed occurs, for example, after a gas surge or in overrun. However, it must be mentioned that this consideration should only apply in the alternative and that the storage of the setpoints before opening the throttle valve has absolute priority.

One circumstance has yet to be considered. Before the multiplier M, a further summation point S4 is provided, at which an air quantity Q _{o is} subtracted from the _target quantity Q _Soll . This measure serves to optimize the work area. The value of 0 should be ₀ should not be greater than the minimum _target air quantity Q _target that occurs, so that the quantity reaching the multiplier M after the summation point S4 is preferably always greater than O. This addition with a negative value of Q _o makes it possible to set the pivot point of the curve or characteristic as close as possible to the working point. If one starts from a desirable ideal case, in which the supplied a _o value lies exactly on the working point, then it is possible to adapt and display the curve with only one iteration step, namely once an offset setting and once an incline setting . But even if the pivot point is lower due to the deviation of the Q _o value from the direct working point, you can manage with fewer iteration steps overall.

• der Offset-Integrator 11 immer dann läuft, also freigegeben ist, wenn die Drosselklappe geschlossen ist, wenn der Steigungsintegrator 12 nicht läuft und die Sperrzeit T₂ abgelaufen ist;
• daß der Steigungsintegrator 12 nur dann läuft, wenn Q_ist + Q_sp + ΔQ ist, wobei Q_sp der beim Öffnen der Drosselklappe jeweils abgespeicherte Wert und ΔQ eine festlegbare Luftmenge ist;
• daß nach einer Steigungsadaption zunächst eine erfolgreiche Offset-Adaption stattfinden muß, d.h. Q_Soll = Q_lst, bevor eine neue Steigungsadaption stattfinden kann;

According to an advantageous embodiment of the present invention to improve the adaptation of the actuator characteristic curve in such a way that a reduction in the iteration steps and thus a faster adaptation is achieved or incorrect adaptations can be avoided in such a way that the slope is not adapted, for example, several times in succession without In the meantime, an offset adaptation takes place, furthermore consists in the fact that:

• the offset integrator 11 always runs, ie is released, when the throttle valve is closed, when the slope integrator 12 is not running and the blocking time T _{2 has} expired;
• that the slope integrator 12 only runs when Q _is + Q _sp + ΔQ, where Q _{sp is} the value stored when the throttle valve is opened and ΔQ is a definable amount of air;
• that has to take place a successful adaptation offset by a first slope adaptation, ie Q _set = Q _actual before a new slope adaptation can take place;

and that, in the case of a slope adaptation, the offset integrator 11 is also simultaneously traced in accordance with a specific calculation rule, as a result of which it is possible to rotate the characteristic curve around the last working point Q _sp and not around 0 ₀ . In the most favorable case (if T _{1 is} very large), the number of required integration steps can be reduced to one step in this way.

In order to be able to use these measures individually and / or preferably as a whole in the idle charge control according to the invention, an additional function circuit block SB is provided according to FIG. 2, which can also take over the functions of the two integrators that lock against one another and the input signals from the output of the memory block SB (via the comparator VG) with respect to the value Q _sp stored when the throttle valve was last opened and the output signals of the two integrators and / or the enable circuits assigned to them. The function block then preferably acts on the release circuits with corresponding output signals and thereby ensures that, in accordance with the measures mentioned above, the offset generator is always released via its release element FG1 when this corresponds to the above-mentioned condition, with correspondingly additionally required input signals being supplied and the slope integrator is only released if the current Q _{actual value is} greater, but at least the same as the value stored when the throttle valve is opened and a definable air volume, because the slope adaptation quickly results in a relatively strong intervention in the output manipulated variable, which can only be approved if the stated condition is met.

Finally, the function block FB is designed in such a way that it interlocks the releases of the offset integrator and the slope integrator, so that it is prevented that changes in the slope are strongly adapted without the base point or pivot point of the characteristic curve being intermittently adjusted due to an offset adaptation undergoes an adjustment. It has already been pointed out above that the invention is particularly suitable for implementation using computer circuits, microprocessors, small computers and the like. is suitable, with the last-mentioned measures in particular representing conditions which are or the like through appropriate program design when using a microprocessor. indicate well and have it processed.

Claims (8)

1. Method is conjunction with a control or regu- . lation system for the speed of an internal combustion engine in the case of idling via an electromechanical final control element, for controlling the air quantity or mass taken in by means of an adaptation of the shape of a characteristic of the continuously operating final control element of the internal combustion engine by converting the controlling variable (Q_set, m _set) fed to the final control element (12, Id-ACT.) by the control or controller output into an adapted electrical manipulated variable (τ) for the final control element in which the controlling variable (Q_set, m_set) is combined multiplicatively and/or by summation with at least one stored value (1₁, 1₂) influencing the offset and/or the slope of the characteristic of the final control element, the stored values representing an output signal of in each case one control loop which is activated in the event of certain operating conditions and, from a comparison of the controlling variable (Q_set, m_set) with an actual measured value of the air-mass or air-quantity measuring device, generates the output signal with which at least one of the stored values (I₁, I₂) is altered to produce a relatively slight control deviation, the value thus altered being stored at the temporal end of the particular operating condition.

2. Method according to Claim 1, characterized in that the values (I₁, 1₂) are stored in integrators and enabled as a function of various operating conditions (idling etc.) of the internal combustion engine in order to influence the electrical manipulated variable (τ) for the final control element.

3. Method according to either of Claims 1 or 2, characterized in that the time constants of the integrators (I₁, 1₂) for offset and slope adaptation are so large that the characteristic adaptation is consequently so slow that the actual idling-speed control is not influenced.

4. Method according to one or more of Claims 1 to 3, characterized in that the slope integrator (1₂) only runs when the actual air quantity (Q_aclual) is greater than or equal to the last air-quantity value (Q_st) stored upon the opening of the throttle valve plus a specifiable air quantity (AQ).

5. Method according to one or more of Claims 1 to 4, characterized in that an interlocking of offset and slope adaptation takes place in such a way that, after each slope adaptation, a successful offset adaptation (Q_set = Qactua_l) first of all takes place before another slope adaptation is enabled.

6. Method according to one or more of Claims 1 to 5, characterized in that, during each slope adaptation, the offset integrator (1₁) is simultaneously corrected in accordance therewith, in such a way that the rotation of the characteristic, in each case brought about by the slope adaptation, takes place about the last operating point in each case (value Q_st stored upon the last opening of the throttle valve).

7. Device in conjunction with a control or regulating arrangement for controlling the speed of an internal combustion engine in the case of idling via an electromechanical final control element for controlling the air quantity'or mass taken in, for carrying out a method according to one of Claims 1 to 3, by means of means for an adaptation of the shape of characteristic of the continuously operating final control element of the internal combustion engine, by converting the controlling variable (Q_set, m_set) fed to the final control element (12, Id-ACT) by the controller output into an adapted electrical manipulated variable (τ) for the final control element, the controlling variable (Q_set, m_set) being combined multiplicatively and/or by summation with at least one.value (1₁, 1₂), from a memory, influencing the offset and/or the slope of the characteristic of the final control element, the stored values representing an output signal of one control loop which is activated in the event of certain operating conditions and, from a comparison of the controlling variable (Q_set, m_set) with an actual measured value of the air-mass or air-quantity measuring device, generates the output signal with which at least one of the stored values (1₁, 1₂) is altered to produce a relatively slight control deviation, the value thus altered being stored at the temporal end of the particular operating condition.

8. Device according to Claim 7, characterized in that additional interlocking means (FB) are provided which effect a reaction or interaction between offset integrator and slope integrator.

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