EP1074719B1 - Method to control an internal combustion engine - Google Patents

Description

State of the art

The invention relates to a method for operating a Internal combustion engine, in particular a motor vehicle, at the fuel, especially in at least two Operating modes, injected into a combustion chamber, at in dependence on a plurality of Emergency running requirements acted on the internal combustion engine and in which the majority of runflat requirements be coordinated. Likewise, the invention relates to a corresponding control device for an internal combustion engine in particular for a motor vehicle.

Such a method and such a control device are known for example from DE 197 31 972 A1. There be different emergency operation functions in different program levels of a control device processed.

From DE 43 26 498 A1 it is known, a so-called Monitoring priority and a so-called control priority in connection with the diagnosis of a vehicle introduce.

In a so-called gasoline direct injection (WO 00/26526), fuel is in a homogeneous operation during the intake phase or in a shift operation during the Compression phase in the combustion chamber of the internal combustion engine injected. The homogeneous operation is preferably for the Full load operation of the internal combustion engine provided while the shift operation for idle and part load operation suitable is. For example, depending on one Desired target mode is in such a direct injection internal combustion engine between the switched over.

The internal combustion engine is continuously on possible Malfunctions checked. Some critical malfunctions can a special emergency operation of the internal combustion engine require. If such a critical error is detected, so are from the function which the error has taken all the necessary measures, to trigger a run-flat. Be multiple errors of Internal combustion engine about the same time or short term determined one after the other, this has the consequence that several such emergency conditions on the Engage internal combustion engine.

In particular, due to the plurality of operating modes an internal combustion engine with gasoline direct injection and the resulting increased possibilities of Malfunctions can be described, for example Simultaneous emergency requirements for conflicts in the Lead implementation.

The object of the invention is a method for operating to create an internal combustion engine with which in the case one or more malfunctions a safe emergency operation achieved and realized.

This task is used in a method of the beginning mentioned type according to the invention by the features of Claim 1 solved.

So it is no longer of that particular function, which has detected an error that triggered emergency operation, but this function only specifies the emergency run request an emergency coordination. There is the emergency run request and possibly other emergency running requirements of others Functions coordinated. Depending on that is then of the emergency coordination of the actual emergency operation triggered.

This means that the actual emergency operation is no longer from the fault-detecting function is triggered directly, but the emergency coordination is interposed. This ensures that several approximately the same time Emergency running requirements no longer lead to conflicts can. Instead, such several are about simultaneous emergency running through the Emergency running coordination processed and with each other coordinated. Only the emergency coordination can then ultimately trigger the actual emergency operation.

According to the invention, the plurality of Emergency running requirements prioritized. Are the Emergency running requirements are not feasible, so they stand for example. in contradiction to each other, so finds a prioritization of pending emergency requirements. This means that one of the received emergency conditions a highest Assigned priority and this emergency request with it is executed first. In this way, the Contradiction resolved and conflicts between the Emergency running requirements are solved.

Furthermore, the invention provides that the Prioritization according to a given priority list is carried out. This makes it possible to set the priorities flexible and flexible to change. In an advantageous embodiment of the invention the majority of runflat requirements on theirs Feasibility checked. It is therefore checked if the individual, of different functions of Internal combustion engine received emergency running requirements Overall, at all feasible, so are executable. is This is the case, lead the incoming Emergency running requirements so easily to an emergency, So this emergency is from the emergency coordination triggered.

It is particularly advantageous if it is determined whether the Majority of runflat requirements in a contradiction to stand by each other. It is therefore checked if the different emergency running requirements in common can be processed or if they are in conflict standing together. If no conflict is detected, so the emergency conditions are feasible and the emergency can be triggered.

In an advantageous embodiment of the invention triggers the prioritized emergency request a system response out. So it is only from the emergency run request with the highest priority triggered a system reaction. there It may be a shutdown of the fuel supply or order a reset of the controller or the like act.

In another advantageous embodiment of the invention the prioritized emergency request has a desired one Operating mode result. In this case, so from the Emergency run request with the highest priority one certain mode requested, then in the from the Internal combustion engine is switched, if they are not already exists.

It is particularly advantageous if the prioritized Emergency run request is stored. That's it possible, an error log or an emergency protocol from which later the occurred error can be reconstructed.

Of particular importance is the realization of the inventive method in the form of a Memory element used for a control unit Internal combustion engine, in particular of a motor vehicle, is provided. It is on the memory element a Program stored on a computing device, especially on a microprocessor, executable and to Execution of the method according to the invention is suitable. As a storage element can in particular an electrical Storage medium are used, for example, a Read-only memory or a flash memory.

Figur 1

zeigt ein schematisches Blockschaltbild eines Ausführungsbeispiels einer erfindungsgemäßen Brennkraftmaschine,

Figur 2

zeigt ein schematisches Blockschaltbild eines Ausführungsbeispiels eines erfindungsgemäßen Verfahrens zum Betreiben der Brennkraftmaschine der Figur 1.

Other features, applications and advantages of the invention will become apparent from the following description of embodiments of the invention, which are illustrated in the figures of the drawing.

FIG. 1

shows a schematic block diagram of an embodiment of an internal combustion engine according to the invention,

FIG. 2

shows a schematic block diagram of an embodiment of a method according to the invention for operating the internal combustion engine of Figure 1.

In the figure 1 is an internal combustion engine 1 of a Motor vehicle shown, in which a piston 2 in a Cylinder 3 is reciprocable. The cylinder 3 is with a combustion chamber 4 provided, inter alia, by the Piston 2, an intake valve 5 and an exhaust valve. 6 is limited. With the inlet valve 5 is an intake pipe. 7 and with the exhaust valve 6, an exhaust pipe 8 is coupled.

In the region of the intake valve 5 and the exhaust valve. 6 protrude an injection valve 9 and a spark plug 10 in the Combustion chamber 4. About the injection valve 9, fuel in the combustion chamber 4 are injected. With the spark plug 10 the fuel in the combustion chamber 4 can be ignited.

In the intake pipe 7 is a rotatable throttle valve 11th accommodated, via the intake pipe 7 air supplied is. The amount of air supplied depends on the Angular position of the throttle valve 11. In the exhaust pipe 8 is housed a catalyst 12, the cleaning of the by the combustion of the fuel resulting exhaust gases serves.

From the exhaust pipe 8 performs an exhaust gas recirculation pipe 13 back to the intake pipe 7. In the exhaust gas recirculation pipe 13 is a Exhaust gas recirculation valve 14 accommodated, with the amount of set in the intake pipe 7 recirculated exhaust gas can be. The exhaust gas recirculation pipe 13 and the Exhaust gas recirculation valve 14 form a so-called Exhaust gas recirculation.

From a fuel tank 15 leads a Tank vent line 16 to the intake 7. In the Tank vent line 16 is a tank vent valve 17th housed with the amount of the intake pipe. 7 supplied fuel vapor from the fuel tank 15th is adjustable. The tank vent line 16 and the Tank vent valve 17 form a so-called Tank ventilation.

The piston 2 is activated by the combustion of the fuel the combustion chamber 4 in a reciprocating motion, the is transmitted to a crankshaft, not shown, and on this a torque exerts.

A controller 18 is of input signals 19 applied, measured by sensors operating variables represent the internal combustion engine 1. For example, that is Control unit 18 with an air mass sensor, a lambda sensor, a speed sensor and the like. Of another is the control unit 18 with an accelerator pedal sensor connected, which generates a signal indicating the position of a operated by a driver accelerator pedal and thus the indicates requested torque. The controller 18 generates Output signals 20, with which via actuators or actuators the behavior of the internal combustion engine 1 are affected can. For example, the controller 18 with the Injector 9, the spark plug 10 and the throttle valve 11 and the like connected to and generates the Activation required signals.

Among other things, the controller 18 is provided to the Control operating variables of the internal combustion engine 1 and / or to regulate. For example, that of the injection valve 9 in the combustion chamber 4 injected fuel mass of the Control unit 18, in particular with regard to a small Fuel consumption and / or a low Controlled pollutant development and / or regulated. To For this purpose, the controller 18 with a Microprocessor in a storage medium, especially in a flash memory a program stored, which is suitable to the said To perform control and / or regulation.

The internal combustion engine 1 of Figure 1 may in a plurality operated by operating modes. So it is possible the Internal combustion engine 1 in a homogeneous operation, a Shift operation, a so-called Kat heating and operate the same. This is explicitly stated on the German patent application DE 198 50 586.8 referenced.

Between the described modes of the Internal combustion engine 1 can be switched back and forth become. Such switches are provided by the controller 18 performed. The triggering of a changeover takes place through the individual functions of the internal combustion engine 1. In the internal combustion engine 1, a plurality of such Functions exist, all a specific mode request the internal combustion engine 1 and thus possibly trigger a changeover between the operating modes.

In the figure 2 a method is shown, which of the Control unit 18 can be executed, and that is suitable for emergency operation of the internal combustion engine 1 realize.

According to the figure 2, a block 21 is provided, in which all Error bits and / or other system variables set or be stored, which led to an emergency run Internal combustion engine 1 should lead. These error bits can e.g. of engine functions or diagnostic functions or The like generated and passed to the block 21 become.

The error bits contained in the block 21 are called Emergency run request or emergency run request to a block 22 passed on a coordination of received Emergency running requirements. This coordination is only required if several emergency conditions come in short succession or about the same time and thus in competition with each other. Is only one single emergency request, it will - as yet will be described - readily further processed.

Decides on several emergency conditions received the block 22 in a step A first, whether the Emergency running requirements are at all feasible, or whether they contradict each other. There is no contradiction of the entered emergency conditions, they will become - As will be described - easily further processed.

Consists between the received emergency running requirements However, if a contradiction, the block 22 leads in one Step B prioritization of the emergency running requirements by. This prioritization can be done according to a preset Priority list or flexible from company sizes of Internal combustion engine 1 are performed. Based on this prioritization will then be the prioritized Emergency running request as described below further processed.

• starre Forderung bzw. starres Verbot bestimmter Betriebsarten der Brennkraftmaschine 1,
• Androsseln der Brennkraftmaschine 1 über die Drosselklappe 11,
• die Drosselklappe 11 wird stromlos gesteuert,
• die Zufuhr von Kraftstoff zu den Einspritzventilen 9 wird abgeschaltet,
• das Steuergerät 18 wird durch einen sogenannten Reset zurückgesetzt,
• es erfolgt eine Begrenzung des von der Brennkraftmaschine 1 erzeugten Moments,
• es erfolgt eine Begrenzung der von der Brennkraftmaschine 1 erzeugten Drehzahl.

In this further processing of the single emergency run request or non-conflicting emergency run requests or the prioritized emergency run request, system reactions are triggered in a step C, which may be, for example, the following:

• rigid demand or rigid prohibition of certain operating modes of the internal combustion engine 1,
• Throttling the internal combustion engine 1 via the throttle valve 11,
• the throttle valve 11 is de-energized,
• the supply of fuel to the injection valves 9 is switched off,
• the controller 18 is reset by a so-called reset,
• there is a limitation of the torque generated by the internal combustion engine 1,
• There is a limitation of the speed generated by the internal combustion engine 1.

The selected system response (s) will then be / implemented a block 23 and realized with it. In which Block 23 may be e.g. to act on engine functions, with which controlled the fuel supply and / or regulated becomes.

In a possible step D, the selected one (s) may System reaction (s) e.g. in one of the triggering in block 21 Function associated error path of a memory 24th be stored.

In the figure 2, a block 25 is further provided, which is a coordination of the requested Operating modes is. These operating modes can be from various functions of the internal combustion engine. 1 be requested. According to the figure 2 apply a Plurality of functions block 25.

This is a "monitoring" feature. This ensures that the internal combustion engine. 1 never generates too much torque as requested. Further it is a function "component protection". Thereby For example, it is ensured that the temperature of the Exhaust pipe 8 is never so high that damage to the Exhaust pipe 8 or the catalyst 12 is to be feared. Next it is the function "adjustability a desired torque of the internal combustion engine 1 and the Compliance with desired lambda limits "and so on.

Next is a function "emergency" of Internal combustion engine 1. This function is at a Emergency running for this emergency mode desired mode of operation Internal combustion engine 1 selected. This emergency run or this Mode is indicated by an arrow 26 from the block 22 triggered or specified.

About the arrow 26 is thus one due to the received Emergency Run Required Mode to Block 25 passed. This makes it possible, not just over the Block 23 directly or directly to certain functions the internal combustion engine 1, but it can also over the block 25 an action in the form of a desired mode of operation.

From the block 25 is by means of a block 27 that Detected operating mode in which the internal combustion engine 1 operate according to the priorities of the block 25 is. This determination is made according to a predetermined Procedures performed, such as in the German Patent Application DE 198 50 586.8 already mentioned is described.

In the figure 2 a Sollbyte 28 is shown, which is the Storage of the described modes of operation Internal combustion engine 1 in the control unit 18 is used. The Target byte 28 has eight bits, not all of which bits need to be occupied. The different operating modes of the Internal combustion engine 1 are each by one of the bits in represents the desired byte 28.

The Sollbyte 28 shown in Figure 2 is to provided, the desired mode, ie the desired Mode of operation of the internal combustion engine 1 to mark. Should the internal combustion engine 1, for example, in homogeneous operation is operated as desired desired mode, so is in the desired byte 28, the corresponding bit is set to "1", while the other relevant bits are all set to "0" are. In the Sollbyte 28 is thus always one of relevant bits set to "1" while the other bits are set to "0".

The bit set to "1" indicates the desired one Target mode in which the internal combustion engine 1 then is switched, provided that this mode is not yet performs.

Claims (8)

1. Method for operating an internal combustion engine (1), in particular of a motor vehicle, in which, in particular in at least two operating modes, fuel is injected into a combustion chamber (4), in which the internal combustion engine (1) is acted on as a function of a plurality of emergency-running requirements, and in which the plurality of emergency-running requirements are coordinated (22), characterized in that the plurality of emergency-running requirements are prioritized (B), and in that the prioritization is carried out in accordance with a predefined list of priorities.
2. Method according to Claim 1, characterized in that the ability of the plurality of emergency-running requirements to be implemented is checked (A).
3. Method according to Claim 2, characterized in that a check is made to determine whether the plurality of emergency-running requirements contradict one another.
4. Method according to one of Claims 1 to 3, characterized in that the prioritized emergency-running requirement initiates a system reaction (C).
5. Method according to one of Claims 1 to 4, characterized in that the prioritized emergency-running requirement results in a desired operating mode (26).
6. Method according to one of Claims 1 to 5, characterized in that the prioritized emergency-running requirement is stored (D).
7. Memory element, in particular a read-only memory or a flash memory, for a controller (18) of an internal combustion engine (1), in particular of a motor vehicle, in which memory element a program is stored which is programmed for use in a method according to one of Claims 1 to 6.
8. Controller (18) for an internal combustion engine (1), in particular of a motor vehicle, the controller (18) being programmed for use in a method according to one of Claims 1 to 6.

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