DE10228355A1 - Internal combustion engine heat regulation involves controlling influencing devices according to prevailing state associated with certain coolant temperatures and/or other operating parameter values - Google Patents

Abstract

The method involves detecting coolant temperature of and other operating parameters and controlling devices for influencing the thermal balance in the engine accordingly. Several main states and at least one superimposition state of the engine-cooling circuit system associated with different coolant temperatures and/or other operating parameter values are defined. The influencing devices are controlled according to the prevailing state. The method involves detecting the temperature of a coolant and other operating parameters and controlling devices (14,24,38,40) for influencing the thermal balance in the engine (10) accordingly. Several main states and at least one superimposition state of the engine-cooling circuit system that are associated with different coolant temperatures and/or other operating parameter values are defined. The influencing devices are controlled according to the prevailing state. A change from the superimposition state can only occur to the associated main state and vice-versa.

Description

The invention relates to a method for heat regulation an internal combustion engine for Vehicles with a coolant circuit and controllable devices for influencing the heat balance the internal combustion engine, wherein a coolant temperature and more Operating parameters of the internal combustion engine are detected and the controllable devices depending on the coolant temperature and the further operating parameters of the internal combustion engine are controlled become.

From the German patent application DE 197 28 351 A1 a method for heat regulation of an internal combustion engine is known, in which a coolant temperature, critical component temperatures, in particular the area between exhaust valves, the so-called land zone, and / or performance characteristics of the internal combustion engine are detected and taken into account in the control. In addition to the temperatures and their change per unit time is recorded. As a performance characteristic, for example, the introduced in a combustion chamber per unit time or duty cycle amount of fuel can be used. For heat regulation electrically driven and controllable water pumps, an electrical thermostat, an electrically driven blind and an electrically driven fan are used. If the internal combustion engine arranged in a vehicle is started, first the water pump and the fan are switched off and the thermostat and the blind are closed. With increasing temperature, the water pump is first put into operation and regulated according to the heat accumulation. Thereafter, the control of the thermostat begins and finally the shutter is opened and the fan starts with the control. If the temperature continues to rise, although all the controllable devices are set to maximum values, the performance of the internal combustion engine is reduced for safety.

With the invention, a needs-based heat regulation an internal combustion engine for vehicles dependent on provided the respective operating and environmental conditions become.

According to the invention for this purpose is a method for thermoregulation an internal combustion engine for vehicles with a coolant circuit and controllable devices for influencing the heat balance provided the internal combustion engine, wherein a coolant temperature and more Operating parameters of the internal combustion engine are detected and the controllable devices depending on the coolant temperature and the further operating parameters of the internal combustion engine are controlled, in which several main states and at least one superposition state associated with a main state Defined the system of internal combustion engine and coolant circuit are the respectively different values of the coolant temperature and / or the further operating parameters are assigned and in which the controllable means for controlling at least the coolant temperature be at least partially controlled differently, with a Change to the overlay state exclusively starting from the assigned main state and from the superposition state exclusively can be done in the assigned main state.

By providing overlay and main states are, the control strategy can be made clear and starting from a main state can in an associated overlay state short-term measures be taken to the system in the intended main state hold. In this way, you can respond quickly and with measures to a current operating situation which would not be feasible by means of a conventional system. For example, by means of an overlay state be tried at high load requirements and unfavorable Ambient conditions the heat balance yet to be kept in the normal operating range.

In a further development of the invention a change between the several main states exclusively in and against a predetermined order of the main states.

In this way it is ensured that a controlled transition in extreme conditions and, in particular, within the regulatory strategy, no jumping outside the prescribed order takes place. This way a can very effective regulation can be achieved without oscillations of the Systems to be feared would.

In a further development of the invention the at least one overlay state for one set predetermined period of time and then is in the assigned Main state changed back.

At the end of the period of time becomes automatic again the superposition state assigned main state set. This way a can Simple control structure can be maintained and still can in the overlay state short-term extreme measures can not be adjusted by means of a conventional regulator further feasible would. About that In addition, this can ensure that the system not persisted in a superposition state, which can not be optimal in the long term.

In a further development of the invention takes place in the main and / or superimposed states at least partially a regulation of the coolant temperature, the engine component temperature and the oil temperature, wherein the control of the coolant temperature with highest priority, the engine component temperature with the second highest priority and the oil temperature with the lowest priority.

over the regulation of the coolant temperature is primarily the need-based cooling for the engine ensured and the heating comfort in the vehicle interior influenced. By means of a Control of the engine component temperature, in particular a web temperature, can be a combustion chamber surface in terms of efficiency-optimized combustion, a better Exhaust emission and a reduced noise emission targeted temperature become. A web temperature is also the most reliable and fastest error indicator in case of malfunction of the cooling system. By means of a control of the oil temperature can be a better efficiency through an optimized warm-up strategy especially in partial load operation. Furthermore becomes an effective motor protection at high load and speed allows. By the chosen Prioritization avoids system malfunctions.

In development of the invention in the main and / or overlay states at least sometimes used different control characteristics.

For example, in case of imminent overrun of limits, a control with aggressive control parameters used whereas with even load a scheme with defensive control parameters are performed can. That way you can Control differences are quickly corrected without overshoots during normal operation or to fear vibrations would.

In a further development of the invention a change in the various states by exceeding or falling below given Limit values of a coolant temperature, a component temperature of the internal combustion engine, an oil temperature the internal combustion engine and / or a load of the internal combustion engine triggered and in individual states the settings of a coolant pump, a mixing valve between a radiator and a bypass circuit, one of a cooler associated fan, a radiator shutter and / or an injection system of the internal combustion engine changed.

By the exact knowledge of the current Condition of the heat balance the internal combustion engine and by the possibility of effective measures to control the heat balance to be able to use up to the reduction of the engine power, can a permitted value range fully utilized with a small safety distance to critical areas become. Nevertheless, due to the different defined states one high security against overheating given the engine.

In development of the invention a first main state by a coolant temperature below a first coolant temperature limit, a Component temperature below a first component temperature limit and / or an oil temperature defined below a first oil temperature limit, wherein in the first main state the coolant pump is turned off, the fan switched off, the mixing valve closed and / or the radiator shutter are closed.

These measures are after a cold start a very fast warming the internal combustion engine possible, because the cooling water not circulated and as a result the heat produced by combustion only at low level is transported away. When closed, the mixing valve closes a coolant line to the vehicle radiator, so that only the bypass line to bypass the vehicle radiator is open.

In development of the invention a second main state through a coolant temperature above the first coolant temperature limit and below a target coolant temperature range, a component temperature above the first component temperature limit and below a component temperature target range and / or an oil temperature above the first oil temperature limit and below an oil temperature target range defined, wherein in the second main state, the cooling medium pump is regulated, the fan switched off, the mixing valve closed and / or the radiator shutter closed are.

Through this second main state will be a controlled warming of the coolant achieved, which is circulated by means of the regulated coolant pump, due to the closed mixing valve but not flows through the vehicle radiator. Since that Mixing valve is still closed, that will be the internal combustion engine flowing through Coolant quickly heated.

In development of the invention a first superposition state associated with the second main state through a coolant temperature immediately below the target coolant temperature range, a component temperature immediately below the component temperature target range and / or an oil temperature immediately below the target oil temperature range defined, wherein in the first superposition state the coolant pump with maximum possible Power is operated, the fan switched off, the mixing valve closed and / or the radiator shutter closed is.

By the first superposition state, advantageously for one limited period of time can be ensured that the engine and the coolant flowing through it have a uniform temperature have reached before in the next Condition is changed.

In a further development of the invention is a third main state by a coolant temperature within a coolant temperature target range, a component temperature within a component temperature target range and / or an oil temperature within ei Defined nes oil temperature target range, wherein in the third main state, the coolant pump and the mixing valve are controlled and a fan off and / or a radiator shutter is closed.

This state uses by regulation the mixing valve already this cooling capacity a vehicle radiator and represents a normal operation by the internal combustion engine is driven in the optimum temperature range.

In development of the invention a second superposition state assigned to the third main state by the third main state corresponding coolant, engine component and oil temperatures and additionally defined high engine load, wherein in the second superposition state, the coolant pump with maximum possible Power operated, the mixing valve is regulated, the fan off and / or a radiator shutter closed is.

By means of this second superposition state can be early on a looming warming through high engine load to be reacted. This is how you try to do that Keep temperatures of the internal combustion engine in the desired range, nor before a significant increase in these temperatures is observed.

In development of the invention a fourth main state by a coolant temperature within a coolant temperature target range, a component temperature within a component temperature target range and / or an oil temperature within an oil temperature target range as well as a high engine load, a high ambient temperature and / or a low vehicle speed defines, being in the fourth Main condition of the coolant pump regulated will, the fan is regulated, the mixing valve to a maximum flow of the Coolant cooler set is and / or the radiator shutter open is.

By means of the fourth main state can then, if the temperatures of the engine still in the target range but move due to further circumstances Temperature rise to be feared is to be reacted by initiating temperature-reducing measures before critical temperatures are reached.

In development of the invention a third superposition state associated with the fourth main state through a coolant temperature immediately below a critical coolant temperature, a component temperature immediately below a critical component temperature and / or an oil temperature immediately below a critical oil temperature as well as a high Engine load, a high ambient temperature and / or a small vehicle speed defined, wherein in the third overlay state the coolant pump and the mixing valve are set to a maximum flow of the coolant radiator, the Radiator shutter is open and / or a fan is regulated.

In this third superposition state, advantageously for a limited amount of time, by maximum possible Coolant flow through the engine and the radiator keep the temperatures below the critical range.

In development of the invention a fifth major condition through a coolant temperature essentially equal to the critical coolant temperature, a component temperature essentially equal to the critical component temperature and / or an oil temperature essentially equal to the critical oil temperature and high engine load, high ambient temperature and / or low driving speed, being in the fifth Main condition the coolant pump and the mixing valve are set to a maximum flow of the coolant radiator, the radiator shutter open is and / or the fan operated at maximum air flow.

In this fifth major state, this mobilizes System the last available standing reserves for lowering the temperature.

In development of the invention a sixth main state through a coolant temperature above the critical coolant temperature, a component temperature above the kriti's component temperature and / or an oil temperature above the critical oil temperature defined, wherein in the sixth main state, the coolant pump and the mixing valve are set to a maximum flow of the coolant radiator, the radiator shutter open is and / or the fan operated with maximum air flow and an injection quantity is reduced.

In a final step will be in sixth main state, the injection quantity is gradually reduced, whereby the engine in each case from thermal destruction preserved becomes. This has the advantage that the vehicle remains mobile, Leave dangerous areas and the nearest repair workshop if necessary can be visited. Is not a malfunction, but only an overload the internal combustion engine, is after reaching the normal operating temperatures the engine again the full engine power available.

In a further development of the invention a charge air cooler dependent on be switched on and off of operating parameters of the internal combustion engine.

In this way, in particular at low outside temperatures over the Temperature of the charge air influences the heat balance of the internal combustion engine be taken.

Further features and advantages of the invention will become apparent from the claims and the following description of a preferred embodiment the invention in conjunction with the drawings. In the drawings show:

1 a schematic representation of an internal combustion engine of a motor vehicle with a cooling circuit for carrying out the method according to the invention,

2 a representation of functional blocks in the inventive method and

3 a representation of the different states that the internal combustion engine with cooling circuit of 1 can take according to the method of the invention.

The schematic representation of 1 shows an internal combustion engine 10 which is provided with a coolant circuit. A flow direction of coolant in the coolant circuit is indicated at various points in each case by an arrow. Starting from an outlet opening 12 of the internal combustion engine 10 Coolant reaches a controllable mixing valve 14 , which is designed as a rotary valve. The mixing valve 14 is by means of a central control unit 16 driven. The transmission of data from the controller 16 to the mixing valve 14 and vice versa is indicated by a dashed double arrow. By means of the mixing valve 14 becomes the engine 10 incoming coolant flow via a bypass line 18 or via a vehicle radiator 20 directed. Downstream of the heat exchanger 20 opens the bypass line 18 into a main line 22 coming from the vehicle radiator 20 comes and to a coolant pump 24 leads. The coolant pump 24 is driven by an electric motor and can by the control unit 16 be controlled. A data exchange between the coolant pump 24 and the controller 16 is indicated by a dashed double arrow. Starting from the coolant pump 24 the coolant returns to the internal combustion engine 10 ,

Upstream of the mixing valve 14 branches a line 26 from the coolant outlet 12 starting, one after the other an exhaust gas recirculation heat exchanger 28 and a heater core 30 interspersed and then into the main line 22 leading to the coolant pump 24 leads.

Another coolant line 32 branches directly from the combustion engine 10 and leads through an oil-water heat exchanger 34 and a charge air heat exchanger 36 back to the main line 22 ,

The cooler 20 is with a radiator shutter 38 and an electric fan 40 provided, both by means of the control unit 16 can be controlled.

The central control unit 16 receives input signals from a component temperature sensor called the combustion chamber surface temperature sensor 42 is formed and with the a Brennraumoberflächen- or web temperature in the internal combustion engine 10 determined and to the control unit 16 can be handed over. By means of an oil temperature sensor 44 becomes an oil temperature of the internal combustion engine 10 recorded and sent to the control unit 16 to hand over. A coolant temperature in the coolant circuit is determined by means of a coolant temperature sensor 46 downstream of the coolant outlet 12 and upstream of the mixing valve 14 recorded and also to the control unit 16 to hand over.

By means of the control unit 16 may be an ignition timing, an injection amount and an injection timing of the internal combustion engine 10 to be changed. The internal combustion engine 10 puts the control unit 16 Actual values available. A data exchange between the control unit 16 and the internal combustion engine 10 is by a dashed double arrow 48 indicated.

By means of the control unit 16 is a regulation of the coolant temperature at the coolant outlet 12 , the combustion chamber surface temperature and the oil temperature of the internal combustion engine 10 realized. The actual values of the coolant temperature at the coolant outlet 12 be by means of the coolant temperature sensor 46 , a combustion chamber surface temperature by means of the combustion chamber surface temperature sensor 42 and an oil temperature by means of the oil temperature sensor 44 recorded and sent to the control unit 16 to hand over. The nominal values of the three reference values coolant temperature at the outlet 12 , Combustion chamber surface temperature and oil temperature are specified by means of maps. So is in the controller 16 a basic map for the coolant temperature at the outlet 12 given as a function of the engine load and the driving speed. By means of the reference variable coolant temperature, the need-based cooling for the engine is ensured in the first place and the heating comfort in the vehicle interior significantly influenced.

Furthermore, in the control unit 16 a map of the web temperature stored as the combustion chamber surface temperature in dependence on the engine speed and the injection quantity. This command value is required for the targeted tempering of the combustion chamber surface, in order to achieve an efficiency-optimized combustion, a better exhaust emission and a reduction of the noise emission. In addition, the web temperature is the most reliable and fastest error indicator in case of malfunction of the cooling system.

As a third reference variable is by means of the controller 16 the oil temperature specified. As a result, a better efficiency can be realized by an optimized warm-up strategy, especially at partial load operation. In addition, an effective motor protection at high load and speed is possible.

The scheme based on the described reference variables by means of the control unit 16 is in the 2 shown schematically. In a functional block 50 Control differences and limits for the operating parameters of the internal combustion engine are determined. Controlled variables are the coolants temperature at the outlet 12 , the web temperature and the oil temperature, wherein a prioritization is provided, the coolant temperature at the outlet 12 the highest priority, the web temperature the second highest priority and the oil temperature the lowest priority. As input variables are in the function block 50 thus the coolant temperature at the outlet 12 , the web temperature and the oil temperature processed, these inputs are used to determine a respective control difference. Further input variables in the function block 50 are an engine speed, a vehicle speed, an injection quantity, an outside air temperature and a refrigerant pressure in an air conditioning system of the motor vehicle. These additional input variables are used to determine operating state-dependent limit values and to classify the current operating state into predefined system states. The input refrigerant pressure is used to control the fan 40 ( 1 ) to influence.

In the block 52 As a result, control differences and limit values are available. On the one hand, these values are sent to a state machine 54 which gives the current operating status and how detailed in connection with 3 is explained measures to control the heat balance of the internal combustion engine 10 pretends. This from the state machine 54 certain actions will be sent to a controller 56 to hand over. The regulator 56 be out of the block 52 also passed the control differences, whereupon the controller 56 Command values are determined and output by the block 58 are shown. The manipulated variables in the block 58 are, for example, pulse width modulated signals (PWM) for controlling the electric coolant pump 24 , designed as a rotary valve mixing valve 14 , the fan 40 as well as the radiator shutter 38 , In addition, signals can be provided for setting an injection quantity as manipulated variables.

A feedback of actual values to the function block 50 , ie of actual values, by means of the sensors 42 . 44 . 46 and possibly other sensors are detected by a connection between the block 58 and the function block 50 symbolizes. The control is designed as a closed loop with feedback, the controllers used are designed as a PI controller with anti-windup reset. This means that when the controlled system is subjected to an extreme disturbance, the PI controllers operate as a pure P controller and in this way reliably prevent vibrations in the controlled system.

Based on 3 will now be described in detail, as in the state machine 54 a current system status is determined and what measures are then set to control the heat balance. The state machine 54 can be between six main states 60 . 62 . 64 . 66 . 68 and 70 as well as three superposition states 72 . 74 and 76 choose. It should also be noted that in the 3 shown structure can be traversed only sequentially in the vertical or horizontal direction. As a result, the system state may change only from one main state to one of the adjacent main states or to an optionally assigned superposition state. For example, the superposition state 72 can only be based on the main state 62 from being reached and from the overlay state 72 The system can only return to its original state 62 move back. Starting from the main state 62 again only the previous main state 60 or the next main state 64 be achieved. This achieves a manageable and effective control strategy.

The main state 60 The system will pick up after a cold start or when the engine is cold. In the main state 60 is a coolant temperature below a first coolant temperature limit, a component temperature below a first component Teilbeteilgrenzwertes and / or an oil temperature below a first oil temperature limit. In order to achieve a rapid heating of the internal combustion engine, are in the main state 60 all controllable devices are not activated or closed. So are in the first main state 60 the coolant pump 24 and the fan 40 switched off and the mixing valve 14 and the radiator shutter 38 are closed. With closed mixing valve 14 is the conduit to the radiator 20 closed and the bypass line 18 open.

With increasing warming of the internal combustion engine 10 The system then takes the main state 62 a, by the relevant temperatures, although above the limits of the state 60 but still below their respective target range. In the main state 62 are the mixing valve 14 and the radiator shutter 38 closed, the fan 40 is off but the coolant pump 24 is regulated. In this state, due to the closed mixing valve 14 the coolant circulated only in the bypass circuit, ie by the bypass line 18 , the wires 26 and 32 with the connected heat exchangers 28 . 30 . 34 and 36 as well as the main line 22 ,

Starting from the main state 62 can be a first overlay state 72 be set. This overlay state 72 is set for a predetermined period of time, and automatically returns to the main state after the predetermined time has elapsed 62 he follows. The transition to the first superposition state 72 takes place when the internal combustion engine 10 has almost reached its operating temperature, that is, that a coolant temperature immediately below the coolant temperature target range, a component temperature immediately below the Bauteililtempe temperature setpoint and / or an oil temperature is immediately below the target oil temperature range. In this first overlay state 72 becomes the coolant pump 24 operated at maximum possible power, whereas the fan 40 is switched off, the mixing valve 14 is closed and the radiator shutter 38 is also closed. By the first superposition state 72 ensures that the coolant in the bypass circuit is evenly heated and that the vehicle radiator 20 only then flows through, if that of the internal combustion engine 10 generated heat no longer through the heat exchanger 28 . 30 . 34 and 36 can be dissipated. This can be done by switching between states 62 and 72 The internal combustion engine and a vehicle interior are heated very quickly before the mixing valve 14 opens.

Starting from the second main state 62 the system can enter the third main state 64 pass. This third main state 64 is defined by the engine having reached its desired operating temperature and thus having a coolant temperature within a coolant temperature target range, a component temperature within a component temperature target range, and / or an oil temperature within an oil temperature target range. In this third major state 64 be the coolant pump 24 and the mixing valve 14 fixed, the fan 40 remains switched off and the radiator shutter 38 remains closed. In the third main state 64 thus becomes the vehicle radiator 20 flows through the heat balance of the internal combustion engine 10 to keep in the target range.

Starting from the third main state 64 a change takes place in the second superposition state 74 when there is a high engine load and thus an increased heat input can be expected. In the second overlay state 74 becomes in contrast to the third main state 64 the coolant pump operated at maximum possible power, the mixing valve 14 continues to be regulated, the fan 40 switched off and the radiator shutter 38 are closed. By the second superposition state 74 For example, the effects of short-term load increases on the heat balance can be compensated. It is advantageous that even before the actual heat input is reacted by an increased engine load, so that a predictive control is possible. The second overlay state 74 is set for a predetermined period of time, after which time the state machine 54 again the third main state 64 established.

If these boundary conditions exist, meaning that the engine has reached its operating temperature, the engine load is still high, and furthermore the ambient temperature is high and the vehicle speed is low, the temperatures rise again and a transition to the fourth main state 66 must be done to keep the temperatures within the target range. In the fourth main state 66 be the coolant pump 24 and the fan 40 regulated, the mixing valve 14 is at a maximum flow through the radiator 20 set and the radiator shutter 38 is opened.

If the coolant temperature, the web temperature and / or the oil temperature in the fourth main state 66 continue to increase and lie immediately below the respective critical temperatures, the system changes to the third superposition state 76 , In order to avoid an increase in the temperatures to the respective critical values, are in the third superposition state 76 the coolant pump 24 and the mixing valve 14 to a maximum flow through the radiator 20 set, the radiator shutter 38 is open and the fan 40 is regulated. After a predetermined period of time, the system exits the third overlay state 76 and goes back to the main state 66 about.

If a driver still insists on his desire for high or maximum engine load at high ambient temperatures and low vehicle speed, ultimately the operating temperatures of the engine reach their critical value. The system then enters the fifth main state 68 in which the last available reserves are mobilized to dissipate heat. For this purpose, in the fifth main state, the coolant pump 24 and the mixing valve 14 set to a maximum flow through the radiator, the radiator shutter 38 is open and the fan 40 is operated with maximum air flow.

Should the internal combustion engine 10 now also exceed the critical operating temperatures, the system changes to the sixth main state 70 , Opposite the fifth main state 68 becomes in the sixth main state 70 gradually the injection quantity of the internal combustion engine 10 reduced, whereby the engine is preserved in any case from thermal destruction. If the coolant temperature, the oil temperature and / or the web temperature are correspondingly reduced again by this measure, the system can be in the fifth main state 68 change back, whereupon the full engine power is available again.

In order to avoid thermal damage after parking a vehicle, the method according to the invention is continued in the context of a tracking function even with the ignition off, possibly restricted, and regulates the temperatures until a condition is reached in which no danger or overheating is to be feared , Only then does the controller switch 16 final self.

Claims (16)

Method for thermoregulation of a fuel engine ( 10 ) for vehicles with a coolant circuit and controllable devices ( 14 . 24 . 38 . 40 ) for influencing the heat balance of the internal combustion engine ( 10 ), wherein a coolant temperature and further operating parameters of the internal combustion engine ( 10 ) and the controllable facilities ( 14 . 24 . 38 . 40 ) as a function of the coolant temperature and the further operating parameters of the internal combustion engine ( 10 ), characterized in that several main states ( 60 . 62 . 64 . 66 . 68 . 70 ) and at least one, a main state ( 62 . 64 . 66 assigned overlay state ( 72 . 74 . 76 ) of the system of internal combustion engine ( 10 ) and coolant circuit are defined, which are respectively assigned to different values of the coolant temperature and / or the further operating parameters and in which the controllable devices ( 14 . 24 . 38 . 40 ) are at least partially controlled differently for controlling at least the coolant temperature, wherein a change in the superposition state ( 72 . 74 . 76 ) exclusively based on the assigned main state ( 62 . 64 . 66 ) and the superposition state ( 72 . 74 . 76 ) exclusively in the assigned main state ( 62 . 64 . 66 ). Method according to claim 1, characterized in that a change between the several main states ( 60 . 62 . 64 . 66 . 68 . 70 ) exclusively in and against a predetermined order of the main states ( 60 . 62 . 64 . 66 . 68 . 70 ). Method according to claim 1 or 2, characterized in that the at least one superimposed state ( 72 . 74 . 76 ) is set for a predetermined period of time and then in the assigned main state ( 62 . 64 . 66 ) is changed back. Method according to one of the preceding claims, characterized in that in the main and / or superposition states ( 60 62, 64, 66, 68, 70, 72, 74, 76) at least partially controlling coolant temperature, engine component temperature, and oil temperature, wherein the highest priority coolant temperature control, the second highest priority engine component temperature, and the lowest priority oil temperature he follows. Method according to claim 4, characterized in that in the main and / or superposition states ( 60 . 62 . 64 . 66 . 68 . 70 . 72 . 74 . 76 ) at least partially different control characteristics are used. Method according to one of the preceding claims, characterized gekennzeichne that a change in the various states by exceeding or falling below predetermined limits of a coolant temperature, a component temperature of the internal combustion engine, an oil temperature of the internal combustion engine and / or a load of the internal combustion engine is triggered and in the individual states the settings of a coolant pump ( 24 ), a mixing valve ( 14 ) between a radiator and a bypass circuit, a radiator ( 20 ) associated fan ( 40 ), a radiator shutter ( 38 ) and / or an injection system of the internal combustion engine ( 10 ) to be changed. Method according to claim 6, characterized in that a first main state ( 60 ) is defined by a coolant temperature below a first coolant temperature limit value, a component temperature below a first component temperature limit value, and / or an oil temperature below a first oil temperature limit value, wherein in the first main state ( 60 ) the coolant pump ( 24 ), the fan ( 40 ), the mixing valve ( 14 ) and / or the radiator shutter ( 38 ) are closed. Method according to claim 6 or 7, characterized in that a second main state ( 62 ) is defined by a coolant temperature above the first coolant temperature limit and below a coolant temperature target range, a component temperature above the first component temperature limit and below a component temperature target range, and / or an oil temperature above the first oil temperature limit and below an oil temperature target range; 62 ) the coolant pump ( 24 ), the fan ( 40 ), the mixing valve ( 14 ) and / or the radiator shutter ( 38 ) are closed. Method according to claim 8, characterized in that a second main state ( 62 ) associated with the first overlay state ( 72 ) is defined by a coolant temperature immediately below the coolant temperature target range, an engine component temperature immediately below the engine component temperature target range, and / or an oil temperature immediately below the target oil temperature range, wherein in the first superposition state ( 72 ) the coolant pump ( 24 ) is operated with maximum possible power, the fan ( 40 ), the mixing valve ( 14 ) and / or the radiator shutter ( 38 ) closed is. Method according to one of claims 6 to 9, characterized in that a third main state ( 64 ) by a coolant temperature within a coolant temperature target range, a component temperature within a component temperature range and / or an oil temperature within an oil temperature target range is defined, wherein in the third main state ( 64 ) the coolant pump ( 24 ) and the mixing valve ( 14 ) and a fan ( 40 ) and / or a radiator shutter ( 38 ) closed is. Method according to claim 10, characterized in that a third main state ( 64 ) assigned second superposition state ( 74 ) by the third main state ( 64 ) corresponding coolant, engine component and oil temperatures and additionally high engine load is defined, wherein in the second superposition state ( 74 ) the coolant pump ( 24 ) with maximum possible power, the mixing valve ( 14 ), the fan ( 40 ) and / or a radiator shutter ( 38 ) closed is. Method according to one of claims 6 to 11, characterized in that a fourth main state ( 66 is defined by a coolant temperature within a coolant temperature target range, a component temperature within a component temperature target range, and / or an oil temperature within an oil temperature target range, and a high engine load, high ambient temperature, and / or low vehicle speed, wherein in the fourth main state ( 66 ) the coolant pump ( 24 ), the fan ( 40 ), the mixing valve ( 14 ) to a maximum flow through the coolant radiator ( 20 ) and / or the radiator shutter ( 38 ) is open. Method according to claim 12, characterized in that a fourth main state ( 66 ) associated third superposition state ( 76 ) is defined by a coolant temperature immediately below a critical coolant temperature, a component temperature immediately below a critical component temperature and / or an oil temperature immediately below a critical oil temperature and a high engine load, a high ambient temperature and / or a small vehicle speed, wherein in the third superposition state Coolant pump ( 24 ) and the mixing valve ( 14 ) to a maximum flow through the coolant radiator ( 20 ), the radiator shutter ( 38 ) is open and / or a fan ( 40 ) is regulated. Method according to one of claims 6 to 13, characterized in that a fifth main state ( 68 ) is defined by a coolant temperature substantially equal to the critical coolant temperature, a component temperature substantially equal to the critical component temperature and / or an oil temperature substantially equal to the critical oil temperature and high engine load, high ambient temperature and / or low vehicle speed, wherein in the fifth main state ( 68 ) the coolant pump ( 24 ) and the mixing valve ( 14 ) to a maximum flow through the coolant radiator ( 20 ), the radiator shutter ( 38 ) is open and / or the fan ( 40 ) is operated at maximum air flow. Method according to one of claims 6 to 14, characterized in that a sixth main state ( 70 ) is defined by a coolant temperature above the critical coolant temperature, a component temperature above the critical component temperature and / or an oil temperature above the critical oil temperature, wherein in the sixth main state, the coolant pump ( 24 ) and the mixing valve ( 14 ) to a maximum flow through the coolant radiator ( 20 ), the radiator shutter ( 38 ) is open and / or the fan ( 40 ) is operated with maximum air flow and an injection quantity is reduced. Method according to one of the preceding claims, characterized that a charge air cooler dependent on switched on and off of operating parameters of the internal combustion engine can be.