EP0243597B1 - Device for correcting the regulation curve of the governor of a diesel engine in a motor car - Google Patents

Description

The invention relates to a device for changing the end regulation characteristic curve starting from the nominal speed according to the preamble of claim 1 and claim 10.

From DE-OS 33 13 632 it is known, by varying the pretension of the main control spring of a mechanical controller, if necessary, by means of an actuating piston controlled by a 3/2-way valve, the end limiting characteristic of the controller depending on e.g. to change the vehicle speed or the gear ratio.

Furthermore, the article "Electronic Diesel Regulation EDR for Commercial Vehicle Engines" in MTZ 44 (1983) 10 p. 378-380 shows an electronic controller for a diesel internal combustion engine, by means of which the internal combustion engine characteristics or the driving characteristics of one by the Internal combustion engine driven vehicle can be influenced.

How should a device be designed, however, that changes the end regulation characteristic of a controller in such a way that on the one hand the internal combustion engine can be operated at a low nominal speed in order to reduce the noise emission, but on the other hand in order to have a sufficiently high connection speed after a switching operation Gear gradation is not necessary, nothing is said about that in the two publications.

The invention is therefore based on the object of providing a generic device which makes it possible for the internal combustion engine to be operated with less noise by reducing its nominal speed, without, however, impairing the user-friendliness of the vehicle by requiring an increased number of switching operations becomes.

The object is achieved by the features of claims 1 or 10. An advantage of this device according to the invention is that regardless of all the forces acting on the vehicle against the driving force when the vehicle accelerates after a switching operation, the connection speed of the internal combustion engine in the next higher gear when the gear below it is turned out lies above the nominal speed in a range in which the internal combustion engine again has a relatively high output or a high torque. The use of an electronic control unit as a controller enables a control map with any number of final control curves to be saved, so that even with minor changes, e.g. the payload or e.g. in the case of slight gradients, it is possible to immediately adapt the final control characteristic to the new vehicle condition.

Further advantageous refinements of the invention can be found in subclaims 2 to 9 and 11 to 15.

• Figur 1 ein Ausführungsbeispiel einer erfindungsgemäßen Vorrichtung zur zuladungsabhängigen Anderung der Endabregelkennlinie in einer Prinzipdarstellung,
• Figur 2a in einem Diagramm x_Rs = f(n) den Einfluß einer bestimmten Fahrzeugzuladung auf den Endabregelverlauf,
• Figur 2b in einem Diagramm N = F(n) den Einfluß der Verschiebung der Endabregelkennlinien auf die jeweiligen Anschlußdrehzahlen,
• Figur 3 in einem Flußdiagramm den Operationsblock zur Aktivierung der einer bestimmten Fahrzeugzuladung zugeordneten Endabregelkennlinie,
• Figur 4 ein Ausführungsbeispiel einer erfindungsgemäßen Vorrichtung zur Änderung der Endabregelkennlinie in Abhängigkeit von der zeitlichen Änderung der Brennkraftmaschinendrehzahl in einer Prinzipdarstellung,
• Figur 5 in einem Diagramm _XRS = f(n) den Einfluß der zeitlichen Änderung der Brennkraftmaschinendrehzahl auf den Endabregelverlauf,
• Figur 6 in einem Flußdiagramm, den Operationsblock zur Aktivierung der einer bestimmten zeitlichen Änderung der Brennkraftmaschinendrehzahl zugeordneten Endabregelkennlinie,
• Figur 7 in einem Diagramm nos = f(n) den Einfluß der zeitlichen Änderung der Brennkraftmaschinendrehzahl auf die Verschiebung der Endabregelkennlinie und
• Figur 8 die Blockfunktionen der elektronischen Steuereinheit in einem Blockschaltbild.

The drawing shows:

• FIG. 1 shows an exemplary embodiment of a device according to the invention for changing the load-reducing characteristic in dependence on the load, in a basic illustration,
• FIG. 2a shows in a diagram x _R s = f (n) the influence of a specific vehicle load on the final regulation process,
• FIG. 2b shows in a diagram N = F (n) the influence of the shift in the end regulation characteristics on the respective connection speeds,
• FIG. 3 is a flowchart of the operation block for activating the final control characteristic assigned to a specific vehicle load,
• FIG. 4 shows an exemplary embodiment of a device according to the invention for changing the final control characteristic as a function of the change in the engine speed over time in a basic illustration,
• FIG. 5 shows in a diagram _XRS = f (n) the influence of the temporal change in the engine speed on the end regulation curve,
• FIG. 6 shows in a flowchart the operation block for activating the final control characteristic associated with a specific change in the engine speed over time.
• FIG. 7 shows in a diagram nos = f (n) the influence of the temporal change in the engine speed on the displacement of the end-control characteristic and
• Figure 8 shows the block functions of the electronic control unit in a block diagram.

In FIG. 1, 1 shows a diesel internal combustion engine driving a vehicle 2, on which an injection pump 3 is arranged. The control rod of the injection pump 3 is actuated by an actuator 4, which in turn is controlled by an electronic control unit 5. The control unit 5 is identical in structure and functions to the electronic diesel controller (EDR) disclosed in MTZ 44 (1983) 10 pages 378-380. The only difference is that in the control unit 5 according to the invention there is additionally an operation block 14 (see FIGS. 3 and 8) for determining vehicle load-dependent final control characteristics, which, like the other operating parameter-dependent characteristics, is also provided in a further control characteristic in a read-only memory of the control unit 5 are filed. In addition to the measured values 7, which are also supplied to the known electronic diesel controller EDR, the control unit 5 according to the invention is also supplied with a signal s corresponding to the vehicle load via line 6. The integrator 11 shown in dashed lines is only used if the vehicle is intended for an area of application in which the vehicle load constantly changes while driving. To generate the signal s, an inductive displacement sensor 9 is arranged on the rear axle 8 of the vehicle 2, which increases the distance a between the rear axle 8 and the vehicle Building 10 determined as a measure of the loading condition of vehicle 2.

FIG. 2a shows in a diagram x _R s = f (n) the qualitative course of a control map 12 stored in the read-only memory of the control unit 5 with an end control characteristic A for an unloaded vehicle and an end control characteristic B for a loading vehicle. x _R s denotes the control rod travel in the diagram and n the engine speed.

When the vehicle is unloaded, the control rod is continuously moved into the zero delivery position according to the characteristic curve A immediately after the nominal speed n _nominal has been reached. If a certain threshold value SW _{z of} the vehicle payload of, for example, 50% of the maximum permissible payload is exceeded, the control rod is initially only minimally withdrawn in a first section I in accordance with the characteristic curve B after the rated speed n _{nominal has been} exceeded and only from a transition area ÜB which is approximately 25% above the nominal speed nNenn, in a second section II it drops steeply into the zero delivery position

Based on the in Figure 2b illustrated diagram N = f (n), which exhibits high n the dependence of the engine power N of the internal combustion engine speed, it is seen that such a control of the control rod results in that above the nominal rotational speed n _N hen respect. A constant power N _{K of} the internal combustion engine whose speed ne is always higher when the vehicle is loaded than the speed n _A when the vehicle is unloaded. Accordingly, even after a shift in the next higher gear stage, the connection speed na 'when the vehicle is loaded is higher than the connection speed n _A ' when the vehicle is unloaded, so that the loaded vehicle immediately after the shift for further acceleration according to the performance curve 13 has a higher output than AN is available to the unloaded vehicle. For a loaded vehicle, a relatively high connection speed must therefore be given after the switching operation, since otherwise the power required to accelerate the loaded vehicle is not available, which results in a drop in speed, which means that a downshift to the next lower gear stage is unavoidable. In order to adapt the final control curve even better to the payload, further final control characteristic curves that lie between the standard characteristic curve A and the maximum shifted characteristic curve B can also be stored. So it is z. B. conceivable that the control rod control is based on a 10% increase in payload shifted by approx. 2.5% of the nominal speed n _N enn final control characteristic.

FIG. 3 shows in the form of a flowchart the operation block 14 additionally integrated in the known electronic diesel controller for activating the final control characteristic assigned to a specific vehicle load.

After detection of the signal s corresponding to the payload and the current internal combustion engine speed n, in the input blocks 15 and 16, the actual payload m _is determined in the operation block 17 according to a fixed characteristic 18 from the signal s. Subsequently, in the branching block 19 there is a query as to whether the payload mz _{u is} greater than a predetermined threshold value SW _z and at the same time the current speed n is greater than the nominal speed n _nominal . If not, that is, either m _is less than SW _z or n is less than n _nominal , the current control rod path _{XRS is determined} in operation block 20 in accordance with block functions 58 to 62 and 64 in FIG. 8, otherwise the current control rod path _{XRS is determined} in operation block 21 determined only as a function of the payload, ie from the map stored in the read-only memory, which contains the final control characteristic B. In this speed range, the other parameters, such remain in the determination of the control rod travel _XRS. B. boost pressure P _L , charge air temperature T _L etc. (see Figure 8), not taken into account.

After determining the current control rod travel _XRS according to one of the blocks 20 or 21, this variable x _R s is transferred via the output block 22 to a suitable converter for conversion into a manipulated variable signal for the actuator 4 (see FIG. 1). Subsequently, a check is carried out in the branch block 23 as to whether the current vehicle speed v is 0. If so, the control branches to its starting point, otherwise to point 24, after which the current speed n is entered in block 16. In this case, the load is entered via the signal s only when the vehicle is stationary, since such a load is normally only loaded and unloaded when the vehicle is stationary. As long as the vehicle speed v is not equal to 0, the load value mzu, which was recorded when the vehicle was last stopped, is the basis for the activation of a final control characteristic. If an area of application is provided in which the payload changes while driving, the signal s can also be entered permanently, in which case the speed _query block 23 is omitted and the control returns directly to its starting point after the output of _XRS in block 22 (see dashed line 25). In this case, it is advisable to provide an integrating element 11 smoothing the signal s in line 6 (see FIG. 1 in dashed lines) in order to prevent the measurement signal to be supplied to the control unit 5 from being temporarily too strong due to the constantly changing dynamic axle loads during the journey is falsified.

Instead of an inductive displacement sensor, a switching element with delayed contact, which is arranged on the underside of the vehicle body and which is actuated from the vehicle axle depending on the deflection, can also be used. If a specific payload mzu has been reached, the switching element gives, but only when it is longer than a predetermined one Time has been operated continuously, a signal to call the final control characteristic B (see Figure 2a) to the control unit. With this switching element, in the case of a load that changes during the journey, it is also taken into account that the switching element, which detects the distance a between the vehicle axle and the vehicle body, can briefly signal a higher loading state than actually present due to varying dynamic axle loads.

genannt, ist ein Maß für die Summe sämtlicher auf das Fahrzeug entgegen der Antriebskraft wirkenden Kräfte, wie z. B. der Reibkraft, der Hangabtriebskraft usw.. Die Hochdrehgeschwindigkeit h wird dabei in einer an späterer Stelle (Figur 6), noch näher beschriebenen Art und Weise aus der Brennkraftmaschinendrehzahl n ermittelt, die neben den übrigen Parametern 30 über den Drehzahlsensor 31 und die Leitung 32 der Steuereinheit 28 zugeführt wird. Auch in dieser Steuereinheit sind die hochdrehgeschwindigkeitsabhängigen Endabregelkennlinien in einem Kennfeld im Festwertspeicher der Steuereinheit 28 abgelegt.FIG. 4 also shows a diesel engine 26 driving a vehicle with an injection pump 27, the control rod of which is actuated by an actuator 29 controlled by an electronic control unit 28. Also in this embodiment, the control unit 28 is similar in structure and functions to the electronic diesel controller disclosed in MTZ 44 (1983) 10 on pages 378-380, but with the difference that in this control unit 28 instead of the operation block 14 In addition, an operation block 36 (see FIG. 6 and FIG. 8) for determining a final regulation characteristic as a function of the temporal change h in the engine speed is provided for the load-dependent determination of a final regulation characteristic. This temporal change h in the engine speed, in the further course "high speed

called, is a measure of the sum of all forces acting on the vehicle against the driving force, such as. B. the friction force, the downhill force, etc. The high speed h is determined in a later place (Figure 6), described in more detail from the engine speed n, which in addition to the other parameters 30 via the speed sensor 31 and the line 32 of the control unit 28 is supplied. In this control unit as well, the high-speed-dependent final control characteristic curves are stored in a map in the read-only memory of the control unit 28.

über einem vorgegebenen Schwellwert SW

, z. B. über 250 min^-1/sec, soll für die Ermittlung des aktuellen Regelstangenweges x_Rs die Endabregelkennlinie 34 die unmittelbar nach Erreichen der Nenndrehzahl n_Nenn steil abfällt, aktiviert werden. Nach Unterschreiten dieses Schwellwertes SW

wird der aktuelle Regelstangenweg x_Rs aus den Endabregelkennlinien 35 ermittelt, die wiederum ab der Nenndrehzahl n_Nenn in je einem ersten Abschnitt I zunächst nur minimal und ab je einem Übergangsbereich ÜB schließlich in je einem zweiten Abschnitt II steil abfallen, wobei sich der Übergangsbereich ÜB mit sinkender Hochdrehgeschwindigkeit h in Richtung höherer Brenn kraftmaschinendrehzahlen n verschiebt, denn je größer die Summe der auf das Fahrzeug entgegen der Antriebskraft wirkenden Kräfte ist, bzw. je kleiner die Hochdrehgeschwindigkeit n ist, desto größer ist während eines Schaltvorganges in die nächsthöhere Gangstufe der Geschwindigkeits verlust des Fahrzeuges (z. B. bei Bergfahrt), bzw. desto geringer ist die in der nächsthöheren Gangstufe gegebene Anschlußdrehzahl und somit auch die verfügbare Leistung um das Fahrzeug noch zu beschleunigen (siehe auch Figur 2b).Such a characteristic diagram 33 is shown in FIG. 5, in which the control rod travel x _{RS is} in turn plotted against the engine speed n. Is the high speed of rotation

above a predetermined threshold SW

, e.g. B. over 250 min ^-1 / sec, for the determination of the current control rod path x _R s, the end control characteristic curve 34, which drops steeply immediately after reaching the nominal speed n _nominal , should be activated. After falling below this threshold SW

the current control rod travel x _R s is determined from the end control characteristic curves 35, which in turn decrease only minimally in a first section I from the nominal speed n _nominal and then steeply decrease in a second section II from a transition area ÜB, the transition area ÜB with decreasing high speed h moves towards higher internal combustion engine speeds n, because the greater the sum of the forces acting on the vehicle against the driving force, or the smaller the high speed n, the greater the loss of speed during a shift into the next higher gear stage of the vehicle (e.g. when driving uphill), or the lower the connection speed given in the next higher gear stage and thus the available power to accelerate the vehicle (see also FIG. 2b).

FIG. 6 shows, in the form of a flow chart, the operation block 36 additionally integrated in the known electronic diesel controller for activating the final control characteristic assigned to a specific high speed n. The high speed of rotation n is determined with the aid of a timer integrated in the electronic control unit, in that the current speed of rotation nm is stored every time after a predetermined time period T _m . Thereafter, the difference is out of the currently active speed n _m and according to the previously elapsed time T _m - stored ₁ speed n _m - ₁ is formed and related to the time period T _m, which results in n for the current high rotational speed of the value. The end of a time period T _m -i is always the beginning of the next time period T _m , the individual time periods being all the same (Tm-1 = Tm = T).

ergibt. Anschließend verzweigt die Steuerung zur Stelle 42. Ist die Zeitspanne T_m noch nicht vorüber (Verzweigungsblock 40), verzweigt die Steuerung direkt zur Stelle 42, von der aus die Ansteuerung der einzelnen Kennfelder bzw. der einzelnen Endabregelkennlinien beginnt. Im Verzweigungsblock 43 wird überprüft, ob die aktuelle Hochdrehgeschwindigkeit n kleiner ist als ein vorgegebener Schwellwert SW_h, der z. B. zwischen 200 und 300 min- ¹/sec liegt und ob gleichzeitig die aktuelle Drehzahl n die Nenndrehzahl n_Nenn schon überschritten hat. Falls nein, wird der aktuelle Regelstangenweg x_Rs in dem Block 44 gemäß den Blockfunktionen 58 bis 62 und 64 in Figur 8 bestimmt, andernfalls erfolgt die Ermittlung von x_Rs nur noch in Abhängigkeit der Hochdrehgeschwindigkeit h unter Zugrundelegung der entsprechenden Endabregelkennlinie. Dies geschieht derart, daß in einem ersten Verzweigungsblock 45 festgestellt wird, ob die Hochdrehgeschwindigkeit h einen ersten Grenzwert GW1 unterschritten hat. Liegt die Hochdrehgeschwindigkeit h noch über diesem Grenzwert GW1, erfolgt in Block 46 die Ermittlung des aktuellen Regelstangenweges x_RS nach der abgespeicherten ersten verschobenen Endabregelkennlinie. Hat die Hochdrehgeschwindigkeit den Grenzwert GW1 bereits unterschritten, verzweigt die Steuerung zum nächsten nicht mehr dargestellten Verzweigungsblock um zu überprüfen, ob ein zweiter Grenzwert über- oder unterschritten ist usw. Dies wiederholt sich dann bis zu einem i-ten Verzweigungsblock 47. Leigt die Hochdrehgeschwindigkeit

noch über einem i-ten Grenzwert GWi, wird der Regelstangenweg x_RS nach dem Block 48 über die Endabregelkennlinie die vor der liegt, die maximal verschoben ist bestimmt. Aus letzterer Kennlinie ergibt sich der Regelstangenweg _XRS im Block 49 dann, wenn die Hochdrehgeschwindigkeit

den i-ten Grenzwert GWi unterschritten hat. Der Wert von i kann dabei beliebig gewählt werden, je nachdem wie genau der Endabregelverlauf an die Hochdrehgeschwindigkeit n angepaßt werden soll.The process in detail looks as follows: After an initial high speed of rotation h _o , which can be any value as a starting value, and the constant time period T = T _m - ₁ = T _m between two speed recordings in block 37, the current one is accepted in input block 38 Speed n. In operation block 39, the respective current high speed n is then determined, and in branching block 40 there is first a check as to whether the predetermined time period Tm for storing the next current speed n _m has already expired. If this is the case, then in operation block 41 first the rotational speed just previously entered n as n _m stored, then n of this speed _m the stored after the end of the preceding time period T m-1 current speed n _m - ₁ is subtracted and the difference to the delay T _m related, from which the current high speed

results. The control then branches to position 42. If the time period T _m has not yet passed (branch block 40), the control branches directly to position 42, from which the control of the individual characteristic diagrams or the individual final control characteristic curves begins. In the branch block 43 it is checked whether the current speed of rotation n is less than a predetermined threshold value SW _h , which, for. B. is between 200 and 300 min- ¹ / sec and whether at the same time the current speed n has already exceeded the nominal speed n _nominal . If no, the current control rod path x _R s is determined in block 44 in accordance with block functions 58 to 62 and 64 in FIG. 8, otherwise this takes place Determination of x _R s only as a function of the high speed h based on the corresponding final control characteristic. This is done in such a way that it is determined in a first branch block 45 whether the high speed of rotation h has fallen below a first limit value GW1. If the high speed of rotation h is still above this limit value GW1, the current control rod travel x _RS is determined in block 46 according to the stored first shifted final control characteristic. If the high speed of rotation has already fallen below the limit value GW1, the control branches to the next branch block, which is no longer shown, in order to check whether a second limit value has been exceeded or fallen short of, etc. This is then repeated up to an i-th branch block 47

even above an i-th limit GWi, the control rod travel x _{RS is determined} according to block 48 via the final control characteristic which lies before that which is maximally shifted. The control rod travel _XRS results from the latter characteristic in block 49 when the high speed of rotation

has fallen below the i th limit GWi. The value of i can be chosen arbitrarily, depending on how exactly the final control curve is to be adapted to the high speed n.

After the current control rod path x _{RS has been passed} on via the output block 50 to a converter in order to generate a corresponding manipulated variable signal, it is checked again in the branching block 51 whether the current speed n is above the nominal speed n _nominal . If it is higher, the control branches back to point 42, because a new determination of the high speed ñ is only necessary when the current speed n has _fallen below the nominal speed n _nominal again. However, in order to be able to continue to determine the current control rod travel x _R s in the area in which the current speed n is higher than the nominal speed nNenn, the current speed n must be recorded in the branch from block 51 to position 42 in a separate input block 52 will.

If the current speed n is again less than the nominal speed nNom, the control branches again to point 53.

zugrundegelegt wird, die noch unmittelbar vor Überschreiten der Nenndrehzahl n_Nenn ermittelt wurde und zum anderen, daß dieser Wert h solange konstant gehalten wird, bis die Nenndrehzahl wieder unterschritten ist.The two branch blocks 43 and 51 have the effect that the speed of rotation is selected precisely for the selection of the end regulation characteristic

on the basis that was determined immediately before the nominal speed n _nominal was exceeded and secondly that this value h is kept constant until the nominal speed is again fallen below.

The determination of the final control characteristic curve corresponding to the respective high speed of rotation h can also be carried out with the aid of a map 54, also shown in the read-only memory of the control unit and shown in FIG. 7, which shows the relationship between the high speed of rotation h and the speed n _üB at which the transition range ÜB (see Figure 5) from the first to the second section of a final control characteristic. Assuming that the slope of the first and second section is the same for all end control characteristics (with the exception of the standard end control characteristic, of course, which drops steeply at nominal speed), each end control characteristic can only be determined by determining its transition range ÜB or the associated speed n _ÜB at a known high rotation speed h can be determined from the stored map 54 shown in FIG. The position of the characteristic curves in the characteristic diagram is model-dependent, with the characteristic curves 55, 56 and 57 showing three conceivable courses qualitatively.

In general, it remains to be said that an overloading of the internal combustion engine to avoid due to high rotational speeds, the transition region of the most displaced Endabregelkennlinie by a maximum of 25% above the nominal rotational speed n _N hen lies.

kann die Endabregelkennlinie auch in Abhängigkeit der Fahrzeugbeschleunigung verschoben werden.Instead of the high speed

the final control characteristic can also be shifted depending on the vehicle acceleration.

The block functions of the electronic control unit are shown in a block diagram in FIG. In the blocks 58 to 62, characteristic maps are stored, from which a specific control rod path is proposed depending on the individual input parameters. Block 58, after checking the incoming vehicle speed v, is to be prevented by a corresponding control rod travel that a predetermined maximum speed _V max can be exceeded. Block 59, in the event that the internal combustion engine is switched to power take-off, sets the speed n to a setpoint speed predetermined by the position a of a hand throttle control, whereby for normal driving operation in block 60 alternatively (symbolically represented by the switch 63) the speed is regulated in accordance with a conventional idle end speed controller as a function of the accelerator pedal position β. In block 61, the control rod travel is to be limited such that a maximum permissible torque M _{perm is} not exceeded, and block 62 limits the injection quantity according to a stored smoke / performance map, inter alia as a function of the pressure p _L and the temperature T _L of a turbocharger in the combustion chamber of the internal combustion engine delivered charge air. The smallest value _XRS is selected in block 64 from these control rod paths determined in detail.

, die aus der aktuellen Drehzahl n bestimmt wird, dargestellt. In dem Ausführungsbeispiel nach Figur 1 wird dem Block 14 das Zuladungssignal s und das Drehzahlsignal n zugeführt, in dem Ausführungsbeispiel nach Figur 4 dem Block 36 dagegen nur das Drehzahlsignal n.8 and 14 in FIG. 8 are the additional operational block according to the invention for determining the final control characteristic either as a function of the signal s corresponding to the vehicle load m or as a function of the high speed of rotation

, which is determined from the current speed n, is shown. In the embodiment according to 1, the payload signal s and the speed signal n are fed to block 14, in the exemplary embodiment according to FIG. 4 block 36, on the other hand, only the speed signal n.

During the start of the internal combustion engine, the current control rod travel x _R s is only specified by the map stored in block 66, the injection quantity being additionally influenced in this operating state by the internal combustion engine temperature T _BKM .

In contrast, when the internal combustion engine is operating, either the control rod travel _XRS determined in block 64 or in control block _XRS determined in block 14 or 36 according to the invention is further processed. This depends on whether the payload threshold SWz is already above or below the high-speed threshold SW _h and whether the current speed n is above the nominal speed n _N nominal or not (see FIG. 3 and FIG. 6 and the associated description). The selection of the respective control rod travel is again represented by a symbolic switch 67 which can assume three switch positions. After the control rod travel xRs has been corrected by the respective fuel temperature T _K in block 68, it is fed as a reference variable to a control circuit for setting and correcting the control rod to the determined position x _R s'.

Claims (15)

1. A device for varying the final regulating characteristic of the regulator of an injection pump, commencing at the rated rotary speed, on a diesel internal combustion engine which drives a vehicle and as a function of vehicle-specific parameters such as for example the vehicle speed, wherein the parameters are ascertained by measuring sensors and are fed to the regulator as a correcting value signal which corresponds to the parameters, characterised in that as a further characteristic the load on the vehicle is ascertained by a measuring sensor (9) the correcting value signal of which so controls the regulator (5) that for a loaded vehicle the final regulating characteristic merges from a first minimally falling portion (I) into a second steeply falling portion (II) and in that starting from the rated rotary speed with the vehicle (2) unladen, increasing loading results in the transition zone (UB) from the first portion to the second being shifted in the direction of higher rotary speeds of the internal combustion engine.

2. A device according to Claim 1 with an electronic control unit as a regulator with digitally electronically stored performance characteristics for final rotary speed adjustment, characterised in that on a basis of the correcting value signal (s) which is fed to the control unit (5) from a stored set (12) of load dependent final control characteristics, the final control characteristic corresponding to the load at any given time can be activated.

3. A device according to Claim 1 or 2, characterised in that displacement of the transition zone (UB) takes place at a maximum of 25% of the rated engine speed.

4. A device according to one of Claims 1 to 3, characterised in that the measuring sensor (9) is constructed as a displacement transducer which ascertains the distance (a) between an axle (8) of the vehicle (2) and its superstructure (10).

5. A device according to one of Claims 1 to 4, characterised in that an integrating member (11) is disposed in the connecting line (6) between the measuring sensor (9) and the regulator (5) for smoothing out the correcting value signal (s) generated by the measuring sensor (9).

6. A device according to one of Claims 1 to 5, characterised in that an increase in the load by in each case 10% of the maximum admissible load results in the transition zone (UB) being displaced by approx. 2.5% of the rated engine speed.

7. A device according to one of Claims 1 to 3, characterised in that the measuring sensor (9) is constructed as a switching member for delayed contacting, which is disposed on the underside of the vehicle superstructure and which can be actuated by an actuating element disposed on an axle of the vehicle.

8. A device according to one of Claims 1 to 5 and Claim 7, characterised in that maximum displacement of the transition zone (UB) is brought about by a given threshold value of the load being exceeded.

9. A device according to one of Claims 1 to 5 and 7 to 8, characterised in that the threshold value amounts to approx. 50% of the maximum admissible load.

10. A device for varying the final regulating characteristic of the regulator of an injection pump, commencing at the rated rotary speed, on a diesel internal combustion engine which drives a vehicle and as a function of vehicle-specific parameters such as for example the vehicle speed, wherein the parameters are ascertained by measuring sensors and are fed to the regulator, as a correcting value signal which corresponds to the parameters, characterised in that as a further characteristic the time-related variation in engine speed or vehicle acceleration is ascertained by a measuring sensor (31) with, on the downstream side, a differentiating stage (39), the correction value signal leaving the differentiating stage (39) so controlling the regulator that if a given threshold value of the time-related variation in engine speed or vehicle acceleration fails to be attained, the final regulating characteristic merges from a first just minimally falling portion (I) into a second steeply falling portion (II) and in that the transition zone (UB) from the first portion to the second, starting from the rated engine speed when the threshold value is exceeded is, with diminishing time-related variation in engine speed or vehicle acceleration displaced in the direction of higher engine speeds.

11. A device according to Claim 10 with an electronic control unit as the regulator, with digitally electronically stored performance characteristics for final engine speed control, characterised in that on a basis of the correcting value signal (s) which is fed to the control unit (28) from a stored set of final regulating characteristics which are dependent upon the time variation in engine speed or vehicle acceleration, the final regulating characteristic corresponding to the time-related variation in engine speed at any given time or to the vehicle acceleration at any given time can be activated.

12. A device according to Claim 10 or 11, characterised in that the measuring sensor (31) is constructed as a rotary speed sensor which ascertains the rotary speed of the flywheel of the internal combustion engine (26).

13. A device according to one of Claims 10 to 12, characterised in that in the case of a time-related variation in engine speed, the threshold value ranges from approx. 200 to 330 min-1/sec.

14. A device according to one of Claims 10 to 13, characterised in that for time-related variations in engine speed of around nil, the transition zone (UB) is displaced by a maximum of 25% of the rated speed.

15. A device according to one of Claims 10 to 14, characterised in that the relevant final control characteristic is ascertained as a function of the time-related variation in engine speed which prevailed immediately before attaining the rated speed.

Images