DE102016220659A1 - Method for controlling an internal combustion engine, computer program product, an engine control function and engine system - Google Patents

Abstract

A method of controlling an internal combustion engine, the method comprising, starting from a valve overlap-free mode (base reference range) for the timing of opening and closing the intake valve and the timing of opening and closing the exhaust valve, detecting the presence of a pre-ignition condition in FIG a combustion chamber of a drive cylinder of the internal combustion engine, for a predetermined period of time setting a valve overlap mode for the timing of opening and closing of the intake valve and for the timing of opening and closing of the exhaust valve, after the predetermined period of time setting the valve spacing mode for the time of Opening and closing the intake valve and for the timing of opening and closing the exhaust valve, computer program product, engine control function and engine system.

Description

The invention relates to a method for controlling an internal combustion engine of a motor vehicle, a computer program product, an engine control function and engine system.

From the DE 102010040271 is a method for setting an emergency operation in a faulty system for detecting pre-ignition in an internal combustion engine known. To prevent damage to the internal combustion engine if the pre-ignition detection system is faulty, a normal path of sensor failure detection, sensor signal evaluation, pre-ignition detection, and counter-fire countermeasures will be interrupted upon diagnosis of the system failure and emergency operation a security path is activated.

The object of the present invention is to provide a method for controlling an internal combustion engine, a computer program product and an engine control function with which respective mechanical loads due to abnormal burns in the working cylinders can be at least partially compensated.

This object is achieved with the features of the independent claims. Further embodiments are given in the dependent on these respective subclaims.

With the solutions according to the invention, it is possible, in particular, to at least partially compensate for and in particular stop stochastic pre-ignition, which in particular can be harmful to the component. In this way, in particular, vibrations on components of the internal combustion engine are reduced or avoided.

• - Ermittlung des Vorliegens eines Vorentflammungszustands in einem Brennraum eines Antriebszylinders des Verbrennungsmotors,
• - Einstellung eines Ventilüberschneidungs-Modus für den Zeitpunkt des Öffnens und Schließens des Einlassventils und für den Zeitpunkt des Öffnens und Schließens des Auslassventils,
• - nach Erfüllung einer Rückstellungs-Bedingung Einstellung des Ventilabstands-Modus für den Zeitpunkt des Öffnens und Schließens des Einlassventils und für den Zeitpunkt des Öffnens und Schließens des Auslassventils.

According to a first aspect of the invention, there is provided a method of controlling an internal combustion engine, the method comprising the steps of, starting from a valve overlap-free mode for the timing of opening and closing the intake valve and the timing of opening and closing the exhaust valve:

• Determination of the presence of a pre-ignition state in a combustion chamber of a drive cylinder of the internal combustion engine,
• Setting a valve overlap mode for the timing of the opening and closing of the intake valve and the timing of opening and closing the exhaust valve,
• - after fulfillment of a reset condition setting of the valve clearance mode for the timing of opening and closing of the intake valve and for the timing of the opening and closing of the exhaust valve.

According to one embodiment of the method according to the invention, it is provided that the valve overlap mode set after the determination of the presence of a pre-ignition state has a valve overlap of at least 20 degrees crank angle a predetermined valve lift to a maximum of 80 degrees crank angle at a predetermined valve lift.

According to a further embodiment of the method according to the invention, it is provided that the setting of a valve overlap mode takes place in a basic operating range of the internal combustion engine, which is an upper operating range in which the internal combustion engine has an engine torque that is between 50% of the maximum engine torque and the maximum Motor torque is.

• - Ermittlung des Vorliegens eines Vorentflammungszustands in einem Brennraum eines Antriebszylinders des Verbrennungsmotors,
• - Einstellung eines Ventilüberschneidungs-Modus bei dem vorgegebenen Ventilhub für den Zeitpunkt des Öffnens und Schließens des Einlassventils und für den Zeitpunkt des Öffnens und Schließens des Auslassventils, wobei der Ventilüberschneidungs-Modus eine Ventilüberschneidung von mindestens 20 Grad Kurbelwinkel bei dem vorgegebenen Ventilhub bis maximal 80 Grad Kurbelwinkel bei dem vorgegebenen Ventilhub hat,
• - nach Erfüllung einer Rückstellungs-Bedingung Einstellung des Basis-Modus für den Zeitpunkt des Öffnens und Schließens des Einlassventils und für den Zeitpunkt des Öffnens und Schließens des Auslassventils.

Furthermore, according to the invention, a method for controlling an internal combustion engine is provided, wherein the method starting from a valve overlap mode as a base mode with a valve overlap of a maximum of 10 degrees crank angle at a predetermined valve lift for the timing of opening and closing of the intake valve and for the Timing of the opening and closing of the exhaust valve comprises the following steps:

• Determination of the presence of a pre-ignition state in a combustion chamber of a drive cylinder of the internal combustion engine,
• Setting a valve overlap mode at the predetermined valve lift at the time of opening and closing the intake valve and at the time of opening and closing the exhaust valve, wherein the valve overlap mode has a valve overlap of at least 20 degrees crank angle at the predetermined valve lift up to 80 degrees Crank angle at the predetermined valve lift,
• - after fulfillment of a default condition setting of the base mode for the timing of opening and closing of the intake valve and for the timing of opening and closing of the exhaust valve.

In this embodiment of the method according to the invention, it may be provided that the valve overlap mode set after the determination of the presence of a pre-ignition state comprises a valve overlap of has a maximum of 40 degrees crank angle at the given valve lift.

Alternatively or additionally, in this embodiment of the method according to the invention can be provided that the setting of a valve overlap mode with a valve overlap between 20 degrees crank angle and 80 degrees crank angle in a basic operating range of the internal combustion engine, which is an upper operating range, in which Internal combustion engine has an engine torque that is between 50% of the maximum engine torque and the maximum engine torque.

In the embodiments of the method according to the invention can be provided that the internal combustion engine is a four-stroke internal combustion engine and in particular a supercharged four-stroke gasoline engine.

In the embodiments of the method according to the invention, it can be provided that the identification of the presence of the pre-ignition state by a sensor and a decision as to whether the sensor detects a predetermined event value. It can be provided that the predetermined event value is a predetermined amplitude of vibrations of a body structure of the internal combustion engine.

In the embodiments of the method according to the invention, it may be provided that the predetermined event for identifying the presence of the Vorentflammungszustands is detected in a before the top dead center of a working cylinder piston extending range and between 30 degrees before top dead center and 20 degrees after the upper Dead center is located.

In the embodiments of the method according to the invention, it may be provided that the predetermined event is the predetermined event value for identifying the presence of the pre-ignition state is a predetermined pressure of a pressure pipe arranged in the intake manifold. It may be provided that the predetermined event value is a predetermined limit pressure and the identification of the presence of Vorentflammungszustands by a pressure sensor and a decision as to whether the pressure sensor detects a pressure above a limit pressure in an extending over the top dead center of a working cylinder piston area which is located between 30 degrees before top dead center and 20 degrees after top dead center.

In the embodiments of the method according to the invention, it may be provided that the predetermined reset condition is a time period in which the knock sensor does not detect a pre-ignition state.

• - eine Motor-Drehzahl bis zu 50% der maximalen Motor-Drehzahl des Motors,
• - eine geforderte Motordrehmoment zwischen 50 % des maximalen Motordrehmoments und dem maximalen Motordrehmoment.

In these embodiments, it can be provided that to determine the time duration in which the knock sensor detects no Vorentflammungszustand, only periods are added, in which the engine is located in an engine operating range, by a range of required engine torque and at the same time Range of engine speeds is defined. It can be provided that the predetermined restoring condition is a predetermined engine operating range in which both of the following conditions are met:

• an engine speed up to 50% of the maximum engine speed of the engine,
• a required engine torque between 50% of the maximum engine torque and the maximum engine torque.

With regard to the provisioning condition, it can alternatively or additionally be provided in the method according to the invention that the predetermined restoring condition has a predetermined number of crankshaft revolutions. In this case, can be set for the number of crankshaft revolutions, a number that is located between 1 and 60.

1. (a) Erhöhung des Kraftstoff-Luft-Verhältnisses um einen vorbestimmten Betrag oder einen vorbestimmten Faktor,
2. (b) Reduktion der Motor-Drehmoment um einen vorbestimmten Betrag oder einen vorbestimmten Faktor;

nach Ablauf der vorbestimmten Zeitdauer Einstellung des Ausgangs-Modus.In the embodiments of the method according to the invention, provision can be made for the method to be set after the determination of the pre-ignition state and before or after setting a valve overlap mode one or more of the following further operating modes of the internal combustion engine to compensate for the determined pre-ignition state:

1. (a) increasing the air-fuel ratio by a predetermined amount or factor,
2. (b) reducing the engine torque by a predetermined amount or factor;

after expiration of the predetermined period of time setting of the output mode.

In this embodiment of the method according to the invention it can be provided that the working modes of the internal combustion engine are selected according to a predetermined order and in particular step (a) before step (b). It can be provided that a working mode is only selected if the presence of a Vorentflammungszustands is determined in the respective previous operating mode.

According to a further aspect of the invention, a computer program product is provided, with which a method according to one of the preceding claims is realized. In particular, a flow function described herein is programmed in the computer program product.

• - eine Vorentflammungs-Erkennungsfunktion, die aufgrund eines Eingangssignals von einem Klopfsensor ermittelt, ob ein Vorentflammungszustand in einem Brennraum eines Antriebszylinders des Verbrennungsmotors vorliegt,
• - eine Ablauffunktion, die derart ausgeführt ist,
  • - dass diese als Basis-Ansteuerungsmodus einen Ventilabstands-Modus für den Zeitpunkt des Öffnens und Schließens des Einlassventils und für den Zeitpunkt des Öffnens und Schließens des Auslassventils vorgibt,
  • - dass diese bei Ermittlung des Vorliegens eines Vorentflammungszustands in einem Brennraum eines Antriebszylinders des Verbrennungsmotors für eine vorbestimmte Zeitdauer einen Ventilüberschneidungs-Modus für den Zeitpunkt des Öffnens und Schließens des Einlassventils und für den Zeitpunkt des Öffnens und Schließens des Auslassventils vorgibt, wobei nach Ablauf der vorbestimmten Zeitdauer wieder der Ventilabstands-Modus für den Zeitpunkt des Öffnens und Schließens des Einlassventils und für den Zeitpunkt des Öffnens und Schließens des Auslassventils eingestellt wird.

According to another aspect of the invention, there is provided a motor control apparatus comprising:

• a pre-ignition detection function that determines whether a pre-ignition state exists in a combustion chamber of a drive cylinder of the internal combustion engine based on an input signal from a knock sensor,
• a flow function that is carried out in such a way
  • that, as the basic driving mode, it specifies a valve-clearance mode for the timing of the opening and closing of the intake valve and the timing of the opening and closing of the exhaust valve,
  • - That this upon determination of the presence of a Vorentflammungszustands in a combustion chamber of a drive cylinder of the internal combustion engine for a predetermined period of time predetermines a valve overlap mode for the timing of opening and closing of the intake valve and for the timing of opening and closing of the exhaust valve, wherein after the predetermined Time period is again set the valve clearance mode for the timing of opening and closing of the intake valve and for the timing of opening and closing of the exhaust valve.

• - eine Vorentflammungs-Erkennungsfunktion, die aufgrund eines Eingangssignals von einem Sensor ermittelt, ob ein Vorentflammungszustand in einem Brennraum eines Antriebszylinders des Verbrennungsmotors vorliegt,
• - eine Ablauffunktion, die derart ausgeführt ist,
  • - dass diese als Basis-Ansteuerungsmodus einen Ventilüberschneidungs-Modus mit einer Ventilüberschneidung von maximal 10 Grad Kurbelwinkel bei einem vorgegebenen Ventilhub für den Zeitpunkt des Öffnens und Schließens des Einlassventils und für den Zeitpunkt des Öffnens und Schließens des Auslassventils vorgibt,
• - dass diese bei Ermittlung des Vorliegens eines Vorentflammungszustands in einem Brennraum eines Antriebszylinders des Verbrennungsmotors für eine vorbestimmte Zeitdauer einen wobei der Ventilüberschneidungs-Modus eine Ventilüberschneidung von mindestens 20 Grad Kurbelwinkel bei dem vorgegebenen Ventilhub bis maximal 80 Grad Kurbelwinkel bei dem vorgegebenen Ventilhub für den Zeitpunkt des Öffnens und Schließens des Einlassventils und für den Zeitpunkt des Öffnens und Schließens des Auslassventils vorgibt, wobei nach Eintreten einer vorgegebenen Bedingung und insbesondere nach Ablauf der vorbestimmten Zeitdauer wieder der Ventilabstands-Modus für den Zeitpunkt des Öffnens und Schließens des Einlassventils und für den Zeitpunkt des Öffnens und Schließens des Auslassventils eingestellt wird.

According to another aspect of the invention, there is provided a motor control apparatus comprising:

• a pre-ignition detection function that determines whether a pre-ignition state is present in a combustion chamber of a drive cylinder of the internal combustion engine based on an input signal from a sensor,
• a flow function that is carried out in such a way
  • that it sets as the basic drive mode a valve overlap mode with a valve overlap of a maximum of 10 degrees crank angle at a predetermined valve lift for the timing of opening and closing of the intake valve and for the timing of opening and closing of the exhaust valve,
• - That this upon determination of the presence of a Vorentflammungszustands in a combustion chamber of a drive cylinder of the internal combustion engine for a predetermined period of time, wherein the valve overlap mode, a valve overlap of at least 20 degrees crank angle at the predetermined valve lift to a maximum of 80 degrees crank angle at the predetermined valve lift for the time of Opening and closing of the intake valve and at the time of opening and closing of the exhaust valve, wherein, after the occurrence of a predetermined condition and in particular after the expiration of the predetermined time again the valve clearance mode for the timing of opening and closing of the intake valve and for the time of opening and closing the exhaust valve is set.

1. (a) der Ventilhub beträgt zwischen 0,05 und 0,5 des maximalen Ventilhubs,
2. (b) der vorgegebene Ventilhub beträgt zwischen 0,05 mm und 4 mm.

In this case, the engine control device may be designed such that the predetermined valve lift is defined according to an upper two of the following provisos:

1. (a) the valve lift is between 0.05 and 0.5 of the maximum valve lift,
2. (b) the predetermined valve lift is between 0.05 mm and 4 mm.

• - zumindest einen und insbesondere mehrere Arbeitszylinder,
• - einen Sensor,
• - die funktional mit dem Sensor in Verbindung stehende Motorsteuerungs-Vorrichtung mit einer Motorsteuerungsfunktion nach dem Anspruch 20 oder 21,
• - eine Nockenwellen-Steuerungsvorrichtung, die mit der Motorsteuerungs-Vorrichtung in Verbindung steht und die aufgrund von Vorgaben derselben eine Verstellung des Zeitpunkts des Öffnens und Schließens des Einlassventils und des Zeitpunkts des Öffnens und Schließens des Auslassventils einstellt.

According to another aspect of the invention, there is provided an engine system comprising:

• at least one and in particular a plurality of working cylinders,
• a sensor,
• the engine-related engine control device functionally related to the sensor having a motor control function according to claim 20 or 21,
• a camshaft control device in communication with the engine control device, which adjusts an adjustment of the timing of the opening and closing of the intake valve and the timing of the opening and closing of the exhaust valve based on presets thereof.

The engine system according to the invention may comprise a supercharged internal combustion engine with the working cylinders.

In the embodiments of the engine system according to the invention it can be provided that the sensor is a sensor arranged on the crankcase for determining oscillation amplitudes.

Alternatively or additionally, it can be provided in the embodiments of the engine system according to the invention that the engine system has an intake manifold device with a respective intake manifold connected to the working cylinder and in particular to the combustion chamber thereof, and that the sensor is a pressure sensor arranged in the intake manifold.

The term of a valve overlap-free mode or valve-gap mode is understood to mean an operating mode of an engine in which the inlet valve of the respective working cylinder opens after the outlet valve of the respective working cylinder is closed.

The term of a valve overlap mode is understood to mean an operating mode of an engine in which the inlet valve of the respective working cylinder opens before the outlet valve of the respective working cylinder is closed. The degree of valve overlap may be determined in particular by the crank angle ("degree KW") with respect to a given valve lift, specifically e.g. 0.5 mm valve lift or 1 mm valve lift or 2 mm valve lift.

Herein, in general, that is to say in the embodiments mentioned here, a valve lift which is between 0.05 and 0.5 of the maximum valve lift can be provided as the respective predetermined valve lift. Alternatively or additionally, the respective predetermined valve lift generally have a value between 0.05 mm and 4 mm.

The valve overlap mode is an operation mode with an overlap spread (reference to the maximum valve lift) or overlap area (reference point is the predetermined valve lift) of the intake valve and the exhaust valve of each working cylinder. The overlap spread may also be referred to as a negative spread with respect to the opening and closing of the intake and exhaust valves of a working cylinder. In the valve overlap mode, the intake valve of the respective working cylinder opens before the exhaust valve of the respective working cylinder is completely closed. A positive spread with respect to the opening and closing of the intake valve and exhaust valve of a working cylinder is when the intake valve of the respective working cylinder opens after the exhaust valve of the respective working cylinder is closed.

In the outlet channel, which is opened or closed by the outlet valve, there is an outlet channel pressure. In the inlet channel, which is opened or closed by the inlet valve, there is an inlet channel pressure. Depending on the engine speed and the outlet channel pressure results in each case a current ratio between the inlet channel pressure and the outlet channel pressure. Depending on this pressure ratio, residual gas flows from the outlet channel into the combustion chamber or fresh gas from the inlet channel via the combustion chamber into the outlet channel.

In particular, in an upper engine operating range, and particularly in the full-load engine operating range of supercharged engines, the ratio between the intake port pressure and the exhaust port pressure is such that fresh gas from the intake port flows into the exhaust port via the combustion chamber. This condition is utilized so as to suppress or terminate a pre-ignition condition in the engine.

In the inventive adjustment of a valve overlap mode after determination of a Vorentflammungszustands to avoid or terminate the same amount of scavenging air at the end of the duty cycle and four-stroke engines at the end of the fourth take is increased and prevents Überspülbetrieb and thus a Vorentflammungszustand in the combustion chamber of the respective working cylinder , The accelerated air and exhaust gas columns fresh air-fuel mixture is sucked into the combustion chamber and a retention of exhaust gas residues in the combustion chamber is reduced.

• - 1 eine funktionale Darstellung einer ersten Ausführungsform des erfindungsgemäßen Verfahren zur Steuerung eines Verbrennungsmotors,
• - 2 eine funktionale Darstellung einer weiteren Ausführungsform des erfindungsgemäßen Verfahren zur Steuerung eines Verbrennungsmotors.

Embodiments of the invention will now be described with reference to the accompanying drawings, in which:

• - 1 FIG. 2 a functional representation of a first embodiment of the method according to the invention for controlling an internal combustion engine, FIG.
• - 2 a functional representation of another embodiment of the inventive method for controlling an internal combustion engine.

The inventive method for controlling an internal combustion engine relates to the operation of an engine. The engine may in particular be a gasoline engine and in particular a supercharged internal combustion engine each with working cylinders.

The internal combustion engine is operatively associated with a motor control device for controlling the internal combustion engine having a drain function. Depending on engine operating ranges, the sequence function generates command signals with which the inlet valve and the outlet valve are opened and closed.

The method according to the invention relates to a change of modes for the control of inlet valve at the inlet channel for the supply of air for combustion and the exhaust valve at the outlet channel for the removal of exhaust gas of the combustion. This can be provided according to the invention, in particular in a predetermined operating range, which is referred to herein as the base operating range or reference operating range.

The basic operating range is commanded by a basic drive mode of the engine control device sequence function.

The basic operating range may be, in particular, an upper operating range or a full load-related operating range. The engine is in this upper operating range in an upper engine torque range and especially in the full load range.

By the term "upper operating range" is defined herein in particular a range that extends from 50% of the maximum engine torque and up to the maximum engine torque. In particular, in this case may additionally be the engine speed up to 50% of the maximum engine speed of the engine. In particular, under full load range, this is defined as a range that extends from 75% of the maximum engine torque and to the maximum engine torque.

In particular, the base operating range may also be a medium operating range with a mean engine torque range extending between 0% and 75% of the maximum engine torque, and more particularly between 0% and 50% of the maximum engine torque.

The engine is designed in a first embodiment such that the engine operates in this upper engine torque range at a given valve lift in a valve-standby mode as a base drive mode. In this there is a non-overlapping engine operation or negative spread or negative overlap area of the intake valve and the exhaust valve of each working cylinder, in which the intake valves of the working cylinder each open after the exhaust valve of the same working cylinder for exhausting the exhaust gas is completely closed. In particular, a valve lift is provided as the predetermined valve lift, which is between 0.05 and 0.5 of the maximum valve lift. This is especially provided in a four-stroke gasoline engine. In particular, this is provided in a four-stroke turbo engine or a "supercharged" four-stroke gasoline engine. The term "supercharged" four-stroke gasoline engine is understood here to mean a four-stroke gasoline engine charged mechanically, in particular by a compressor or compressor or electrically driven compressor or by an exhaust-gas turbocharger (ATL).

The engine is configured in a second embodiment such that the engine operates in this upper engine torque range in a specific valve overlap mode as the base mode. The specific valve overlap mode can be defined in particular by the fact that the engine operates with a valve overlap of a maximum of 10 degrees crank angle at a given and especially at 1 mm valve lift. In particular, a valve lift is provided as the predetermined valve lift, which is between 0.05 and 0.5 of the maximum valve lift.

According to the method of controlling an internal combustion engine according to the present invention, when the engine controller receives information about the existence of a pre-ignition state in a combustion chamber of a working cylinder of the internal combustion engine, the mode of operation is changed from the respective one of the basic mode and the pilot mode in a pre-ignition compensation mode. The base mode is an output mode that can be understood as a normal mode in the affected engine torque range.

In a first embodiment, when the basic mode of the engine is a valve overlap-free mode, according to the present invention, after detecting the existence of a pre-ignition state as the pre-ignition compensation mode, a valve overlap mode is set. In this case, the valve overlap mode set after the determination of the presence of a pre-ignition state may have a valve overlap of at least 20 degrees crank angle at the respectively predetermined valve lift and in particular at a valve lift between 0.5 mm and 4 mm valve lift up to a maximum of 80 degrees crank angle at the respectively predetermined valve lift and in particular have a valve lift between 0.5 mm and 4 mm valve lift. In particular, the valve overlap mode set after the determination of the presence of a pre-ignition condition may have a valve overlap of a maximum of 40 degrees crank angle at the given valve lift and in particular at a valve lift between 0.5 mm and 4 mm valve lift.

According to a further embodiment, it can also be provided that the engine of a base mode of the engine, a valve overlap free mode with a valve overlap of a maximum of 10 degrees crank angle at the respective predetermined valve lift and in particular at a valve lift between 0.5 mm and 4 mm valve lift is switched to a pre-ignition compensation mode. In this case, according to the present invention, after detecting the existence of a pre-ignition state as a pre-ignition compensation mode, a valve overlap mode is set which has a valve overlap of at least 20 degrees crank angle at the given valve lift and in particular at 1 mm valve lift up to a maximum of 80 degrees crank angle at the respectively predetermined one Valve lift and in particular at a valve lift between 0.5 mm and 4 mm valve lift has.

The change from the normal mode or the basic operating range may be made by a variable valve timing device or camshaft timing device that is operatively connected to and commanded by an engine control device. A sensor and in particular a knock sensor for determining a pre-ignition state is in turn connected to the engine control device.

The sensor for detecting a pre-ignition state in the combustion chamber of a working cylinder may be designed according to several alternatives.

According to one embodiment, the sensor for detecting a pre-ignition state is designed as a seismic sensor and attached to the body structure of the engine and in particular the crankcase. The amplitudes respectively detected by this sensor, in particular within a given frequency range, as event values are compared in a motor control device with a pre-ignition limit value, in this case with a limit amplitude, which, when the pre-ignition limit value is exceeded, is detected by a respective detected amplitude Defines pre-ignition status value for the presence of a pre-ignition state and sends a trigger value or a trigger signal to a command function.

Alternatively or additionally, the sensor for detecting a Vorentflammungszustands be designed as a pressure sensor. In particular, the sensor for detecting a Vorentflammungszustands or pressure sensor may be arranged in a suction pipe connected to the respective working cylinder. The pressures respectively sensed by this pressure sensor as event values in an engine control device with a pre-ignition limit value, in this case compared with a limit pressure, which if the pre-ignition limit value is exceeded by a respectively detected pressure, a pre-ignition status value for the presence defines a pre-ignition state and sends a trigger value or a trigger signal to a command function.

The engine control device has an engine control function with a compensation function that determines or identifies a pre-ignition condition value for the presence of the pre-ignition condition based on signals received from the pre-ignition sensor or knock sensor. To identify the presence of the pre-ignition condition by the pre-ignition sensor, the engine control function may include a comparison function that compares the event value currently sensed by the pre-ignition sensor with a predetermined event value and, in the event that the pre-ignition sensor includes an event value an amount above the event value, sends a trigger value or a trigger signal to a command function of the engine control function, which then generates a command signal and transmitted to the variable valve timing device.

In general, it is provided that the comparison function compares the current value respectively detected by the pre-ignition sensor or knock sensor with a predetermined limit value, and in the event that the value determined by the pre-ignition sensor has an amount above the limit value, a trigger value or Trigger signal sends to a command function.

The compensation function can furthermore have an influencing function, which includes the fulfillment of an additional trigger condition for generating the trigger value or the trigger signal. The trigger condition may in particular be defined in such a way that the working-cylinder piston is located in an area extending beyond the top dead center of a working-cylinder piston in order to generate the trigger value or the trigger signal. This range may be, in particular with respect to the working cycle of the working cylinder between 30 degrees before top dead center and 70 degrees after top dead center, in particular 30 degrees after top dead center.

In the case that the base mode is a valve overlap-free mode, according to an embodiment of the invention, after determining the presence of a pre-ignition state in a combustion chamber of a power cylinder, adjustment of a valve overlap mode for the timing of opening and closing of the intake valve and the timing of opening and closing the exhaust valve. In this case, provision may be made in particular for the valve overlap mode set after the determination of the presence of a pre-ignition state to have a valve overlap of at least 20 degrees crank angle at 1 mm Valve lift up to 80 degrees crank angle at 1 mm valve lift.

In the case that the base mode is a valve overlap-free mode with a valve overlap of a maximum of 10 degrees crank angle at 1 mm valve lift, according to one embodiment of the invention, after determining the presence of a pre-ignition state in a combustion chamber of a drive cylinder, an adjustment of a valve overlap Mode with a valve overlap of at least 20 degrees crank angle with 1 mm valve lift to a maximum of 80 degrees crank angle with 1 mm valve lift.

• - zumindest einen und insbesondere mehrere Arbeitszylinder,
• - einen Vorentflammungs-Sensor,
• - die funktional mit dem Klopfsensor in Verbindung stehende Motorsteuerungs-Vorrichtung mit der Kompensationsfunktion und der Kommandierungsfunktion,
• - die Vorrichtung zur variablen Ventilsteuerung und insbesondere die Nockenwellen-Steuerungsvorrichtung, die mit der Motorsteuerungs-Vorrichtung in Verbindung steht.

Thus, according to the invention there is also provided an engine system comprising:

• at least one and in particular a plurality of working cylinders,
• a pre-ignition sensor,
• the functionally related to the knock sensor engine control device with the compensation function and the command function,
• the variable valve timing device, and more particularly the camshaft timing device associated with the engine control device.

Specifically, the variable valve timing apparatus may be a variable camshaft controller or camshaft control apparatus that, due to the receipt and presence of the command signal, adjusts the intake camshaft, or the exhaust camshaft, or both, based on the command signal so that the engine is in normal mode or in the basic operating range the valve overlap mode and with a corresponding command signal and vice versa. The camshaft control device may in particular comprise a phaser coupled to the camshaft, which is hydraulically or electrically adjusted and thereby adjusts the camshaft.

The command function may include a reset function that generates a command signal that causes the camshaft controller to set the normal mode or the base operating range from the valve overlap mode. The default function may be performed to generate the default command signal when a predetermined default condition is met.

The reset function may be performed such that the default command signal is generated when, as a default condition, the measured value detected by the knock sensor and, in particular, the pressure sensor falls below a reset threshold.

Alternatively or additionally, the reset function may be implemented such that it generates a reset command signal when, as the reset condition, a predetermined period of time has elapsed since the valve overlap mode was activated. The time duration may be defined by a time interval or a number of crankshaft revolutions. In this case, the number of crankshaft revolutions may have a value between 1 and 60.

According to one embodiment, in order to determine the time duration in which the knock sensor does not detect a pre-ignition condition, only time periods are added in which the engine is operated in an engine operating range that extends through a range of required engine torque and optionally a range of engine torque. Speed range is defined. This means that when leaving the engine operating range, the time period in which the engine is operated outside this range would not be counted as summable time.

• - ein gefordertes Motordrehmoment zwischen 50 % des maximalen geforderten Motordrehmoment und dem maximalen Motordrehmoment und
• - eine Motor-Drehzahl bis zu 50% der maximalen Motor-Drehzahl des Motors.

In particular, it may be provided that the engine operating range defined for determining the time duration is defined by the fulfillment of the following two conditions:

• a required motor torque between 50% of the maximum required motor torque and the maximum motor torque and
• - An engine speed up to 50% of the maximum engine speed of the engine.

In the 2 is shown a further embodiment of the method according to the invention.

To carry out this embodiment of the method, the engine control function of the engine control device includes a scheduling function commanding a selection and sequence of alternative operating modes of the internal combustion engine. The comparison function is functionally connected to the sequence function and activates it as soon as the sequence function receives the trigger value or the trigger signal from the comparison function.

The sequence function sends out information for setting a plurality of operating modes of the internal combustion engine starting from an output mode and after determining the pre-ignition state of the command function in a chronological order, wherein the command function as a working mode of the plurality of operating modes, the camshaft control device commanded from an output mode to the valve overlap mode.

• - Erhöhung des Kraftstoff-Luft-Verhältnisses um einen vorbestimmten Betrag oder einen vorbestimmten Faktor;
• - Reduktion des Motor-Drehmoments um einen vorbestimmten Betrag oder einen vorbestimmten Faktor.

As at least one other working mode, the command function commands the engine controller in at least one of the following working modes:

• - Increasing the air-fuel ratio by a predetermined amount or a predetermined factor;
• - Reduction of the engine torque by a predetermined amount or a predetermined factor.

1. (a) Einstellung eines Ventilüberschneidungs-Modus für den Zeitpunkt des Öffnens und Schließens des Einlassventils und für den Zeitpunkt des Öffnens und Schließens des Auslassventils;
2. (b) Erhöhung des Kraftstoff-Luft-Verhältnisses um einen vorbestimmten Betrag oder einen vorbestimmten Faktor, wozu die Ablauffunktion über ein entsprechendes Signal an die Kommandierungsfunktion eine Motor-Anfettungsfunktion aktiviert.
3. (c) Reduktion des Motor-Drehmoments um einen vorbestimmten Betrag oder einen vorbestimmten Faktor, wozu die Ablauffunktion über ein entsprechendes Signal an die Kommandierungsfunktion eine Drehmomenten-Reduktionsfunktion aktiviert.

In particular, the sequence function may be implemented such that it commands the following concrete sequence of working modes:

1. (a) setting a valve overlap mode for the timing of opening and closing the intake valve and timing of opening and closing the exhaust valve;
2. (B) increase the air-fuel ratio by a predetermined amount or a predetermined factor, for which the sequence function activates a motor-enrichment function via a corresponding signal to the command function.
3. (C) reduction of the engine torque by a predetermined amount or a predetermined factor, for which the sequence function activates a torque reduction function via a corresponding signal to the command function.

In particular, the sequence function can be designed such that it activates the command function via a control signal to set the output mode after the predetermined time has expired.

Also in this embodiment, the command function may include a reset function that generates a command signal to the engine control function that resets the normal mode or the base operating range. The default function may be performed to generate the default command signal when a predetermined default condition is met. The reset function may be performed such that the default command signal is generated when, as a default condition, the measured value detected by the knock sensor and, in particular, the pressure sensor falls below a reset threshold. Alternatively or additionally, the reset function may be implemented such that it generates a reset command signal when, as the reset condition, a predetermined period of time has elapsed since the valve overlap mode was activated. The time duration may be defined by a time interval or a number of crankshaft revolutions. In this case, the number of crankshaft revolutions may have a value between 1 and 60.

In particular, the sequence function can be designed such that it activates the command function in a predetermined order.

Also, the flow function may be performed such that it activates the command function only to a certain working mode, if the presence of a pre-ignition state is still determined.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102010040271 [0002]

Claims (29)

A method of controlling an internal combustion engine, the method comprising, starting from a valve overlap-free mode for the timing of opening and closing the intake valve and for the timing of opening and closing the exhaust valve, the steps of: Determination of the presence of a pre-ignition state in a combustion chamber of a drive cylinder of the internal combustion engine, Setting a valve overlap mode for the timing of the opening and closing of the intake valve and the timing of opening and closing the exhaust valve, - after fulfillment of a reset condition setting of the valve clearance mode for the timing of opening and closing of the intake valve and for the timing of the opening and closing of the exhaust valve. Method according to the Claim 1 wherein the valve overlap mode set after the determination of the presence of a pre-ignition condition has a valve overlap of at least 20 degrees crank angle a predetermined valve lift up to a maximum of 80 degrees crank angle for a given valve lift. The method of claim 1, wherein adjusting a valve overlap mode occurs in a base operating range of the internal combustion engine that is an upper operating range where the engine has an engine torque that is between 50% of the maximum engine torque and the maximum engine torque. A method of controlling an internal combustion engine, the method starting from a valve overlap mode as a base mode with a valve overlap of a maximum of 10 degrees crank angle at a predetermined valve lift for the timing of opening and closing of the intake valve and for the timing of opening and closing of the exhaust valve the following steps: Determination of the presence of a pre-ignition state in a combustion chamber of a drive cylinder of the internal combustion engine, Setting a valve overlap mode at the predetermined valve lift at the time of opening and closing the intake valve and at the time of opening and closing the exhaust valve, wherein the valve overlap mode has a valve overlap of at least 20 degrees crank angle at the predetermined valve lift up to 80 degrees Crank angle at the predetermined valve lift, - after fulfillment of a default condition setting of the base mode for the timing of opening and closing of the intake valve and for the timing of opening and closing of the exhaust valve. Method according to the Claim 4 wherein the valve overlap mode set after the determination of the presence of a pre-ignition condition has a valve overlap of a maximum of 40 degrees crank angle at the predetermined valve lift. Method according to the Claim 4 or 5 wherein the setting of a valve overlap mode with a valve overlap between 20 degrees crank angle and 80 degrees crank angle in a base operating range of the internal combustion engine, which is an upper operating range in which the engine has an engine torque that is between 50% of the maximum engine torque and the maximum motor torque. Method according to one of the preceding claims, wherein the internal combustion engine is a four-stroke internal combustion engine and in particular a supercharged four-stroke gasoline engine. The method of any one of the preceding claims, wherein the identification of the presence of the pre-ignition condition by a sensor and a decision is made as to whether the sensor detects a predetermined event value. Method according to the Claim 8 wherein the predetermined event value is a predetermined amplitude of vibrations of a body structure of the internal combustion engine. Method according to the Claim 8 wherein the predetermined event is detected in an area extending before top dead center of a power cylinder piston and located between 30 degrees before top dead center and 20 degrees after top dead center. Method according to the Claim 8 wherein the predetermined event value is a predetermined pressure in the intake manifold of a working cylinder. Method according to the Claim 11 wherein the predetermined event value is a predetermined limit pressure and the identification of the presence of the pre-ignition state by a pressure sensor and a decision is made as to whether the pressure sensor detects a pressure above the limit pressure in a range extending above the top dead center of a working cylinder piston that is between 30 Degrees before top dead center and 20 degrees after top dead center. The method of any one of the preceding claims, wherein the predetermined default condition is a period of time in which the knock sensor does not detect a pre-ignition condition. Method according to the Claim 13 wherein for determining the length of time that the knock sensor detects no pre-ignition condition, only time periods are added in which the engine is located in an engine operating range that defines a range of requested engine torque and a range of engine speeds is. Method according to the Claim 14 wherein the predetermined restoring condition is a predetermined engine operating range in which both of the following conditions are met: an engine speed up to 50% of the maximum engine speed of the engine, a required engine torque between 50% of the maximum engine torque and maximum motor torque. Method according to one of Claims 1 to 12 wherein the predetermined default condition has a predetermined number of crankshaft revolutions. Method according to the Claim 16 wherein a number is set for the number of crankshaft revolutions, which is located between 1 and 60. Method according to one of the preceding claims, wherein the method after the determination of the Vorentflammungszustands and before or after setting a valve overlap mode, one or more of the following other operating modes of the internal combustion engine to compensate for the determined pre-ignition state are set: (a) increasing the air-fuel ratio by a predetermined amount or factor, (b) reducing the engine torque by a predetermined amount or factor; after expiration of the predetermined period of time setting of the output mode. Method according to the Claim 18 , wherein the working modes of the internal combustion engine are selected according to a predetermined order and in particular step (a) before step (b). Method according to the Claim 19 , wherein a working mode is selected only if the presence of a Vorentflammungszustands is determined in the respective previous operating mode. Computer program product, with which a method according to one of the preceding claims is realized. Motor control device, comprising: a pre-ignition detection function that determines whether a pre-ignition state exists in a combustion chamber of a drive cylinder of the internal combustion engine based on an input signal from a knock sensor, a flow function that is carried out in such a way that, as the basic driving mode, it specifies a valve-clearance mode for the timing of the opening and closing of the intake valve and the timing of the opening and closing of the exhaust valve, - That this upon determination of the presence of a Vorentflammungszustands in a combustion chamber of a drive cylinder of the internal combustion engine for a predetermined period of time predetermines a valve overlap mode for the timing of opening and closing the intake valve and for the timing of opening and closing of the exhaust valve, wherein after the predetermined Time period is again set the valve clearance mode for the timing of opening and closing of the intake valve and for the timing of opening and closing of the exhaust valve. Motor control device, comprising: a pre-ignition detection function that determines whether a pre-ignition state is present in a combustion chamber of a drive cylinder of the internal combustion engine based on an input signal from a sensor, a flow function that is carried out in such a way that it sets as the basic drive mode a valve overlap mode with a valve overlap of a maximum of 10 degrees crank angle at a predetermined valve lift for the timing of opening and closing of the intake valve and for the timing of opening and closing of the exhaust valve, - That this upon determination of the presence of a Vorentflammungszustands in a combustion chamber of a drive cylinder of the internal combustion engine for a predetermined period of time, wherein the valve overlap mode, a valve overlap of at least 20 degrees crank angle at the predetermined valve lift to a maximum of 80 degrees crank angle at the predetermined valve lift for the time of Opening and closing of the intake valve and at the time of opening and closing of the exhaust valve, wherein, after the occurrence of a predetermined condition and in particular after the expiration of the predetermined time again the valve clearance mode for the timing of opening and closing of the intake valve and for the time of opening and closing the exhaust valve is set. Motor control device after the Claim 23 wherein the predetermined valve lift is defined according to an upper two of the following provisos: (a) the valve lift is between 0.05 and 0.5 of the maximum valve lift, (b) the predetermined valve lift is between 0.05 mm and 4 mm. Motor control device after the Claim 24 , where the given valve lift is 1 mm. Engine system, comprising: - at least one and in particular a plurality of working cylinders, - a sensor, - the motor-control device, which is functionally connected to the sensor and has an engine control function after the engine Claim 20 or 21 a camshaft control device in communication with the engine control device, which adjusts an adjustment of the timing of the opening and closing of the intake valve and the timing of the opening and closing of the exhaust valve based on presets thereof. Motor system after the Claim 26 wherein the engine system comprises a supercharged engine with the working cylinders. Motor system after the Claim 26 or 27 wherein the sensor is a sensor arranged on the crankcase for determining oscillation amplitudes. Motor system after the Claim 26 or 27 wherein the engine system comprises a suction pipe device with a respective suction pipe connected to the working cylinder and in particular to the combustion chamber thereof, wherein the sensor is a pressure sensor arranged in the suction pipe.

Images