DE102015216501A1 - Control device for an internal combustion engine - Google Patents

Abstract

A control unit controls intake and exhaust VVT mechanisms such that opening and closing timings are changed to achieve intake and exhaust VVT target phases α_in and α_ex, which extend a valve overlap time under the condition that a rapid one in a boost region Acceleration request of the driver is present. The control unit deactivates a change of the opening and closing timings to the intake and exhaust VVT target phases α_in and α_ex under the condition that the increase amount of the requested torque in the charging region is smaller than a threshold value B, so that the intake and exhaust VVT mechanisms are controlled to achieve initial phases α_in0 and α_ex0. The initial phases α_in0 and α_ex0 cause the valve overlap time to be shortened with respect to the intake and exhaust VVT target phases α_in and α_ex, and maintain the valve overlap time allowing a torque corresponding to the requested and output torque.

Description

Technical area

The present invention relates to control devices for an internal combustion engine, and more particularly to control devices for an internal combustion engine with a supercharger.

General state of the art

A known control device for an internal combustion engine with a supercharger is configured to control an exhaust VVT mechanism and an intake VVT mechanism according to the rate of change of the accelerator opening. This control changes an overlap time between an exhaust valve and an intake valve (see, for example, FIGS Japanese Patent Application Publication No. 2013-253558 hereinafter referred to as Patent Document 1).

When it is determined that the rate of change of the accelerator opening is equal to or greater than a threshold such that there is a quick acceleration request, the known control device for an internal combustion engine respectively changes the closing timing of the exhaust valve and the closing timing of the intake valve with a rate of change higher than if there is a normal acceleration request. This increases the valve overlap time. This control device for an internal combustion engine increases the acceleration performance at a rapid acceleration.

List of pamphlets

Patent document

• [Patent Document 1] Japanese Patent Application Publication No. 2013-253558

Summary

Technical task

The known control device for an internal combustion engine improves drivability during rapid acceleration. Unfortunately, extending the valve overlap time during a charge range through the supercharger may increase the likelihood that unburned fuel air will flow back into the intake manifold due to a rebound of exhaust air back into the intake manifold. The known control device for an internal combustion engine may therefore result in the formation of soot and / or deposits due to an increase in the temperature of the inner wall of the intake passage.

Accordingly, the present invention aims to provide control devices for an internal combustion engine capable of improving drivability while reducing the formation of soot and / or debris during the charging region.

Solution of the task

The present invention provides a control apparatus for an internal combustion engine, which includes a supercharger and a variable valve actuation mechanism for adjusting opening and closing timings of the exhaust valve and / or the intake valve. The control device includes a control unit configured to drive the variable valve actuation mechanism so that when the driver requests acceleration in a charging area in which the supercharger is charging, the opening and closing timings are set to a target opening timing and a target -Schließzeitpunkt be set so that a valve overlap time between the exhaust valve and intake valve is extended. The control unit is further configured to disable the setting of the opening and closing timings to the target opening timing and the target closing timing under the condition that a change amount of the driver-requested torque per unit time is less than a predetermined value in the charging area that the variable valve actuation mechanism is controlled so as to determine the opening and closing timings: causing a shortening of the valve overlap time as compared with the target opening timing and the target closing timing; and which maintain a valve overlap time that allows a torque corresponding to the requested and output torque.

Advantageous Effects of the Invention

The present invention improves drivability while reducing the development of soot and / or debris during the charging area.

Brief description of the drawings

1 FIG. 10 is a schematic diagram of a vehicle having a control apparatus for an internal combustion engine according to an embodiment of the present invention; FIG.

2 is a flowchart showing the sequence of operations of a Valve overlap control performed by an ECU (Electronic Control Unit) according to the embodiment of the present invention;
and

3 FIG. 10 is an example of a timing diagram illustrating how the phases of the intake VVT mechanism and the exhaust VVT mechanism change according to a torque request.

Description of the embodiment

Hereinafter, referring to the 1 to 3 An embodiment of the present invention is described.

Referring to 1 includes a vehicle 1 , which includes a control device for internal combustion engines according to the embodiment, a motor 2 as an internal combustion engine and a motor control unit 10 ,

The motor 2 gets a cylinder block 3 and a cylinder head 4 , the top of the cylinder block 3 is attached. In the cylinder block 3 is a cylinder 3a formed in which a piston 21 installed so that it moves back and forth.

In the upper area of the cylinder 3a is a combustion chamber 5 educated. The combustion chamber 5 is through the top surface of the piston 21 and the bottom surface of the cylinder head 4 limited. The motor 2 is designed as a four-stroke engine, which executes a series of four cycles, namely an intake stroke, a compression stroke, a power stroke and an exhaust stroke, during which the piston 21 in the cylinder 2a moved back and forth twice.

The piston 21 is over a connecting rod 21a coupled with a crankshaft, not shown. The connecting rod 21a converts the reciprocation of the piston 21 in a rotational movement of the crankshaft.

At the cylinder head 4 is a spark plug 40 attached, and in the cylinder head 4 are an injector 30 , an inlet channel 41 and an exhaust duct 42 appropriate. The injector 30 , which is designed as a direct injection fuel injector, injects directly into the combustion chamber 5 Fuel that is compressed and is supplied from a fuel tank, not shown, by a fuel pump, not shown. The spark plug 40 is located on the cylinder head 4 so that its electrode enters the combustion chamber 5 protrudes. An igniter, not shown, adjusts the spark timing of the spark plug.

In the inlet channel 41 is an inlet valve 43 arranged. The inlet valve 43 is formed such that it is in accordance with the rotation of an intake cam mounted on an intake camshaft, not shown 46 opens or closes. The inlet valve 43 opens to the inlet channel 41 to open, and close to the inlet channel 41 close.

In the outlet channel 42 is an exhaust valve 44 arranged. The outlet valve 44 is configured to be in accordance with the rotation of an exhaust cam mounted on an exhaust camshaft, not shown 47 opens or closes. The outlet valve 44 opens to the exhaust duct 42 to open, and closes to the exhaust duct 42 close.

An intake tract 50 is with the intake duct 41 coupled. The intake tract 50 serves to over the inlet channel 41 Air in the combustion chamber 50 introduce. In the intake tract 50 are an air filter 51 , a compressor 52 , a charge air cooler 53 and a throttle 54 intended. The air filter 51 is used for air cleaning and the compressor 52 compresses the air. The intercooler 53 cools the compressed air and the throttle 54 adjusts the air volume.

An exhaust tract 60 is with the exhaust duct 42 coupled. The exhaust tract 60 serves to get out of the combustion chamber 5 over the outlet channel 42 remove discharged exhaust gases from the vehicle. In the exhaust tract 60 are an exhaust gas turbine 62 , a catalyst 63 and an unillustrated silencer provided. The exhaust gas turbine 62 is driven by the exhaust stream, the catalyst 63 cleans the exhaust gases and the silencer, not shown, dampens the sound.

The exhaust gas turbine 62 is with the compressor 52 coupled. The energy generated by the exhaust gas driven by the exhaust gas flow 62 is generated by the compressor 52 used for compressing air. The compressor 52 and the exhaust gas turbine 62 form a turbocharger as a supercharger 6 ,

A wastegate 64 is for the turbocharger 6 intended. The wastegate 64 is capable of exhaust gas flow into the gas turbine 62 to regulate. The wastegate 64 regulates the exhaust gas flow into the exhaust gas turbine 62 , so that the boost pressure caused by the turbocharger 6 obtained pressure of the intake air is controlled. The wastegate 64 For example, it consists of an electromagnetic valve. The engine control unit 10 controls the opening or closing of the wastegate valve 64 ,

The engine control unit 10 comprises a microcomputer consisting of, for example, a central processing unit (CPU), a random access memory (RAM), a read-only memory (ROM), and an input / output interface. The CPU is running a Signal processing according to previously stored in the ROM programs using a cache function in the RAM. The ROM stores various control constants and various schedules.

With the input of the engine control unit 10 are various sensors comprising a pressure sensor 101 , a crankshaft sensor 102 and an accelerator pedal position sensor 103 connected.

The pressure sensor 101 is used to measure the pressure of the internal combustion engine 2 supplied air, that is, the intake pressure of the intake air, downstream of the throttle valve 54 ,

The crank angle sensor 102 measures the rotation of a signal rotor mounted on one end of the crankshaft not shown, thereby measuring the crank angle of the crankshaft, not shown. The engine control unit 10 calculates the engine speed according to the crank angle generated by a signal input from the crank angle sensor 102 is represented.

The accelerator pedal position sensor 53 measures an accelerator pedal opening representing the amount of depression of an unillustrated accelerator pedal by the driver.

With the output of the engine control unit 10 various devices are connected, comprising the injector 30 , the spark plug 40 , the throttle 54 , a variable intake valve control mechanism, or intake VVT mechanism 110 , and a mechanism for variable exhaust valve control, or exhaust VVT mechanism 111 ,

The intake VVT mechanism 110 is used to set the opening and closing times of the inlet valve 43 , The intake VVT mechanism 110 changes the phase of the intake camshaft, which is the intake cam 46 by means of a hydraulic pressure or an electromagnetic force rotates relative to the movement of the crankshaft, whereby the opening and closing timing of the intake valve 43 be set.

The outlet VVT mechanism 111 is used to set the opening and closing times of the exhaust valve 44 , The outlet VVT mechanism 111 changes the phase of the exhaust camshaft, which is the exhaust cam 47 rotates by means of a hydraulic pressure or an electromagnetic force, relative to the movement of the crankshaft, whereby the opening and closing timing of the exhaust valve 44 be set.

The engine control unit 10 controls the drive of each of the intake and exhaust VVT mechanisms 110 and 111 , The control of the inlet and outlet VVT mechanisms 110 and 111 allows in the engine 2 the embodiment, an extension or shortening of the valve overlap time, during which both the inlet valve 43 and the exhaust valve 44 are open. The inlet and outlet VVT mechanisms 110 and 111 form a mechanism for variable valve actuation.

The engine control unit 10 serves as a request torque calculation unit 11 indicative of the driver request torque corresponding to that of the accelerator pedal position sensor 103 calculated accelerator opening.

In particular, in the ROM, the engine control unit 10 a request torque calculation map is stored. The request torque calculation map includes the ratio between the accelerator opening and the request torque previously determined by experiments. The engine control unit 10 thus refers to the request torque calculation map corresponding to the accelerator pedal position and calculates the corresponding request torque.

The engine control unit 10 also serves as a control unit 12 containing the inlet and outlet VVT mechanisms 110 and 111 according to the request torque for lengthening or shortening the valve overlap time controls.

In particular, in the ROM, the engine control unit 10 a valve overlap time calculation map is stored. The valve overlap time calculation map includes the valve overlap time previously determined by experiments, corresponding to the request torque. The engine control unit 10 thus refers to the valve overlap time calculation map corresponding to the request torque and calculates the corresponding valve overlap time.

The engine control unit 10 determines VVT target phases to achieve the calculated valve overlap time and causes an indication or a reset of the opening and closing timings of the intake valve 43 and the exhaust valve 44 , whereby the VVT target phases are achieved.

The VVT target phases become the respective opening and closing timings of the intake valve 43 and opening and closing timings of the exhaust valve 44 certainly. The VVT target phase for the intake valve 43 is hereinafter referred to as VVT target phase and the VVT target phase for the exhaust valve 44 referred to as outlet VVT target phase.

In a charging area, during which the turbocharger 6 performs a charge, performs the embodiment, depending on whether an acceleration request from the driver occurs, an extension or shortening of the valve overlap time, which in particular by a in 2 shown valve overlap control is performed.

Hereinafter, referring to 2 coming from the engine control unit 10 The embodiment described valve overlap control described. The valve overlap control is cyclically performed after predetermined time intervals.

Referring to 2 determines the engine control unit in step S1 10 whether a target intake pressure calculated based on the request torque is equal to or greater than a threshold value A. In particular, the engine control unit determines 10 whether the operating range of the turbocharger 6 within the charging area.

The engine control unit 10 refers to a target intake pressure map stored in the ROM that contains the ratio between the request torque and the target intake pressure previously determined by experiments so as to calculate the target pressure based on the corresponding request torque.

The threshold A varies depending on the operating conditions of the engine 2 which include, for example, engine speed, engine load, engine torque, torque change rate, and intake pressure. The engine control unit 10 refers to a map that the previously determined by experiment relationship between the operating conditions of the engine 2 and the threshold A, thereby determining a value of the threshold value A accordingly.

Once it is determined in step S1 that the target intake pressure is lower than the threshold value A, the engine control unit determines 10 that there is no charging area. In this case, the engine control unit performs 10 in step S8, a normal control and terminates the valve overlap control. In a normal control, the engine control unit controls 10 the inlet and outlet VVT mechanisms 110 and 111 , At this time, the opening and closing timings of each of the intake and exhaust valves become 43 and 44 set to the normal opening and closing timings in a non-charging area.

Otherwise, if it is determined in step S1 that the target intake pressure is equal to or greater than the threshold value A, the engine control unit determines 10 in step S2, whether the request torque increases and whether a change amount of the request torque is equal to or greater than a predetermined threshold B.

In particular, the engine control unit determines 10 Whether there is an acceleration request of the driver, that is, a quick acceleration of the driver in the embodiment in this operation. The change amount of the request torque is the change amount of the request torque per unit time, and in the embodiment, represents the increase amount of the torque request per unit time.

Threshold B varies depending on the operating conditions of the engine 2 , The engine control unit 10 refers to a map that the previously determined by experiment relationship between the operating conditions of the engine 2 and the threshold B, thereby determining a value of the threshold B accordingly.

• (1) eine derartige Vorstellung oder Rückstellung der Öffnungs- und Schließzeitpunkte des Einlassventils 43, dass die Öffnungs- und Schließzeitpunkte des Einlassventils 43 mit der Einlass-VVT-Sollphase übereinstimmen, und
• (2) eine derartige Vorstellung oder Rückstellung der Öffnungs- und Schließzeitpunkte des Auslassventils 44, dass die Öffnungs- und Schließzeitpunkte des Auslassventils 44 mit der Auslass-VVT-Sollphase übereinstimmen.

Once it is determined in step S2 that the request torque increases and the change amount of the request torque is equal to or higher than the threshold B, the engine control unit determines 10 in that a rapid acceleration request of the driver is present. Subsequently, the engine control unit initiates 10 in step S3

• (1) Such an idea or provision of the opening and closing timings of the intake valve 43 in that the opening and closing times of the inlet valve 43 coincide with the inlet VVT set phase, and
• (2) such an idea or provision of the opening and closing timings of the exhaust valve 44 in that the opening and closing times of the exhaust valve 44 match the outlet VVT target phase.

• (1) eine Einlass-VVT-Sollphase α_in, die vor einer schnellen Beschleunigungsanforderung mehr vorgeht und die entsprechenden Soll-Öffnungs- und Schließzeitpunkte definiert, und
• (2) eine Auslass-VVT-Sollphase α_ex, die vor einer schnellen Beschleunigungsanforderung mehr nachgeht und die entsprechenden Soll-Öffnungs- und Schließzeitpunkte definiert.

In particular, the engine control unit determines 10 as soon as it is determined that there is a fast acceleration request,

• (1) an intake VVT target phase α_in, which proceeds more before a rapid acceleration request and defines the corresponding target opening and closing timings, and
• (2) an outlet VVT target phase α_ex, which more takes place before a rapid acceleration request and defines the corresponding target opening and closing times.

The purpose of this determination is to extend the valve overlap time before the fast acceleration request.

• (1) die Öffnungs- und Schließzeitpunkte des Einlassventils 43 gemäß einer Zeitkonstante τ1 vor- oder nachgehen, um mit der Einlass-VVT-Sollphase α_in übereinzustimmen, und
• (2) die Öffnungs- und Schließzeitpunkte des Auslassventils 44 gemäß einer Zeitkonstante τ1 vor- oder nachgehen, um mit der Auslass-VVT-Sollphase α_ex übereinstimmen.

Thereafter, the engine control unit controls 10 the inlet and outlet VVT mechanisms 110 and 111 such that

• (1) the opening and closing timings of the intake valve 43 advance or follow a time constant τ1 to match the inlet VVT target phase α_in, and
• (2) the opening and closing timings of the exhaust valve 44 in accordance with a time constant τ1, to match the outlet VVT target phase α_ex.

The time constant τ1 varies depending on the operating conditions of the engine 2 , The engine control unit 10 refers to a map that the previously determined by experiment relationship between the operating conditions of the engine 2 and the time constant τ1, thereby correspondingly determining a value of the time constant τ1. It should be noted that the time constant τ1 is a stepwise, ie relatively steep, in other words slow, change in the opening and closing timings of the intake and exhaust valves 43 and 44 allows.

The above-mentioned engine control unit 10 controls the inlet and outlet VVT mechanisms 110 and 111 such that the opening and closing timings of the intake valve 43 with the inlet VVT target phase α_in and that the opening and closing timing of the exhaust valve 44 coincide with the outlet VVT target phase α_in to thereby extend the valve overlap time. This control of the inlet and outlet VVT mechanisms 110 and 111 is executed under the condition that there is a rapid acceleration request of the driver in the charging area.

Otherwise, if it is determined in step S2 that the request torque does not increase and / or that the change amount of the request torque is smaller than the threshold B, the engine control unit determines 10 in step S5, that there are no fast acceleration requests of the driver. In this case, the engine control unit causes 10 in that, according to a time constant τ2, the opening and closing timings of the intake valve 43 coincide with an initial phase α_in0 and that the opening and closing times of the exhaust valve 44 coincide with an initial phase α_ex0.

The initial phase α_in0 determines the opening and closing timings of the intake valve 43 ; these opening and closing timings of the intake valve 43 cause a shortening of the valve overlap time compared to the intake VVT target phase α_in and allow the output of a torque corresponding to the request torque.

The initial phase α_ex0 determines the opening and closing times of the exhaust valve 44 ; these opening and closing times of the exhaust valve 44 cause a shortening of the valve overlap time compared to the outlet VVT target phase α_ex and allow the output of a torque corresponding to the request torque.

The time constant τ2 varies depending on the operating conditions of the engine 2 , The engine control unit 10 refers to a map that the previously determined by experiment relationship between the operating conditions of the engine 2 and the time constant τ2, thereby correspondingly determining a value of the time constant τ2. The time constant τ2 is greater than the time constant τ1. Accordingly, the engine control unit changes 10 the opening and closing timings of each of the intake and exhaust valves 42 and 43 slower than with the time constant τ1.

The above-mentioned engine control unit 10 deactivates a change in the values of the opening and closing timings of the intake and exhaust valves described in step S3 43 and 44 to coincide with the corresponding intake VVT target phase α_in and exhaust VVT target phase α_ex. This deactivation is carried out under the condition that the amount of change of the request torque is smaller than the threshold B in the charging area. The above-mentioned engine control unit 10 also controls the intake and exhaust VVT mechanisms such that the opening and closing timings of the intake valve 43 coincide with the initial phase α_in0 and that the opening and closing times of the exhaust valve 44 coincide with the initial phase α_ex0. This control is executed under the condition that in the charging area, the amount of change of the request torque is smaller than the threshold B.

The engine control unit 10 For example, set the throttle 54 or the wastegate valve 64 one to the supercharging pressure of the turbocharger 6 to set to a value that allows reaching the request torque.

After the process in step S3, the engine control unit determines 10 in step S4, whether the difference ΔTr between the request torque and an actual torque is equal to or smaller than a threshold value E and whether the change amount of the request torque is equal to or smaller than a threshold value F.

The threshold E is a threshold value for determining whether ΔTr has dropped to a magnitude that can be used to determine that the actual torque corresponds to the driver's demand torque. The threshold value F is a threshold value for determining whether the amount of change of the request torque has dropped to a magnitude from which it can be determined that the driver's quick acceleration request has been withdrawn.

The thresholds E and F vary depending on the operating conditions of the engine 2 , The engine control unit 10 refers to a map that the previously determined by experiment relationship between the operating conditions of the engine 2 and each of the thresholds E and F, thereby determining the values of the thresholds accordingly.

In particular, the engine control unit determines 10 in step S4, whether a quick acceleration request of the driver has been withdrawn. That is, the engine control unit 10 determines whether a smooth ride is performed at a constant accelerator opening, a slow acceleration is performed with a smaller amount of change of the accelerator opening or a slow deceleration is performed with a smaller amount of change of the accelerator opening.

When it is determined in step S4 that the difference ΔTr between the request torque and an actual torque is greater than the threshold value E and / or the change amount of the request torque is greater than the threshold value F, the engine control unit determines 10 in that the driver's rapid acceleration request persists. In this case, the engine control unit repeats 10 the process of step S3.

Otherwise, if it is determined in step S4 that the difference ΔTr between the request torque and the actual torque is equal to or smaller than the threshold value E and the change amount of the request torque is equal to or smaller than the threshold value F, the engine control unit determines 10 in that the driver's rapid acceleration request has been withdrawn. In this case, the engine control unit performs 10 the process of step S5.

• (1) eine Übereinstimmung der Öffnungs- und Schließzeitpunkte des Einlassventils 43 mit der Einlass-VVT-Sollphase α_in verursachen, und
• (2) eine Übereinstimmung der Öffnungs- und Schließzeitpunkte des Auslassventils 44 mit der Auslass-VVT-Sollphase α_ex verursachen.

In particular, the engine control unit performs 10 the operation in step S5 on the condition that in the charging area, the rapid acceleration request is withdrawn while the engine control unit 10 the inlet and outlet VVT mechanisms 110 and 111 so drives that they

• (1) a correspondence of the opening and closing timings of the intake valve 43 with the inlet VVT target phase α_in, and
• (2) a coincidence of the opening and closing timings of the exhaust valve 44 with the outlet VVT target phase α_ex cause.

In particular, the engine control unit causes 10 in that, according to the time constant τ2, the opening and closing timings of the intake valve 43 with the initial phase α_in0 and the opening and closing timing of the exhaust valve 44 coincide with the initial phase α_ex0.

Subsequently, the engine control unit determines 10 in step S6, if the target intake pressure is equal to or lower than a threshold value H In particular, the engine control unit determines 10 whether the charging area is completed, ie whether the operating range of the turbocharger 6 within the non-charging area.

The threshold H varies depending on the operating conditions of the engine 2 , The engine control unit 10 refers to a map that the previously determined by experiment ratio between the operating conditions of the engine 2 and the threshold H, thereby determining the values of the threshold H accordingly.

Once it has been determined that the target intake pressure is higher than the threshold H, the engine control unit goes 10 to step S2 and repeats the operations of step S2 and the subsequent steps.

• (1) die Öffnungs- und Schließzeitpunkte des Einlassventils 43 gemäß einer Zeitkonstante τ3 vor- oder nachgehen, um mit einer normalen Einlass-VVT-Phase β_in übereinzustimmen, und
• (2) die Öffnungs- und Schließzeitpunkte des Auslassventils 44 gemäß einer Zeitkonstante τ3 vor- oder nachgehen, um mit einer normalen Auslass-VVT-Phase β_ex übereinzustimmen.

Otherwise, if it is determined in step S6 that the target intake pressure is equal to or lower than the threshold value H, the engine control unit controls 10 in step S7, the inlet and outlet VVT mechanisms 110 and 111 such that

• (1) the opening and closing timings of the intake valve 43 in accordance with a time constant τ3 to match a normal inlet VVT phase β_in, and
• (2) the opening and closing timings of the exhaust valve 44 in accordance with a time constant τ3, to match a normal outlet VVT phase β_ex.

The time constant τ3 varies depending on the operating conditions of the engine 2 , The engine control unit 10 refers to a map that the previously determined by experiment relationship between the operating conditions of the engine 2 and the time constant τ3, thereby correspondingly determining a value of the time constant τ3. The time constant τ3 is greater than the time constant τ1. Accordingly, the engine control unit changes 10 the opening and closing times of the admission and exhaust valves 43 and 44 slower than with the time constant τ1.

In step S8, the engine control unit changes 10 then the operation to a normal control in the non-charging region, whereby the valve overlap control is terminated.

Hereinafter, the operations of the control device for internal combustion engines according to the embodiment will be described.

Referring to 3 is the operating range of the turbocharger 6 set to the non-charging area during a smooth running until a time t1 in which the opening and closing timings of the intake and exhaust valves 43 and 44 are set to a corresponding normal intake VVT phase β_in and normal exhaust VVT phase β_ex.

Thereafter, at time t1, due to an increase in the request torque in accordance with a driver's slow acceleration request, the operating range of the turbocharger changes 6 from a non-charging area to a charging area. At this time, the opening and closing timings of the intake and exhaust valves become 43 and 44 corresponding to a normal intake VVT phase β_in and normal exhaust VVT phase β_ex.

Subsequently, after the completion of the slow acceleration at the time t2, a rapid increase in the torque in response to a quick acceleration request of the driver at a time t3 causes the amount of change of the request torque beyond the threshold B to increase. This causes a change in the opening and closing timings of each of the intake and exhaust valves 43 and 44 values based on a respective normal intake VVT phase β_in and normal exhaust VVT phase β_ex to values based on an intake VVT target phase α_in and exhaust VVT target phase α_ex. At this time, the opening and closing timings of each of the intake and exhaust valves change 43 and 44 gradually. This results in an immediate change of the opening and closing timings of each of the intake and exhaust valves 43 and 44 to values based on a corresponding inlet VVT set phase α_in and outlet VVT set phase α_ex.

An immediate change in the opening and closing times of the intake and exhaust valves 43 and 44 to values based on a respective intake VVT target phase α_in and exhaust VVT target phase α_ex may cause an actual phase, which is an actual VVT phase, to exceed a corresponding VVT target phase. This can have an effect on on-board diagnostics (OBD).

In particular, such overshoot may result in a time required for a change from an actual phase to a corresponding target VVT phase to exceed an OBD determination time, such that the OBD determines that a malfunction is the intake and exhaust -VVT mechanisms 110 and 111 is present.

The aim of the embodiment is to avoid such a determination of a fault. Specifically, the embodiment temporarily changes the OBD determination time when a rapid change in the opening and closing timings of the intake and exhaust valves 43 and 44 to the values based on a respective intake VVT target phase α_in and exhaust VVT target phase α_ex. The OBD determination time is extended so that no determination of a failure is made even if, in the case of a rapid change in the opening and closing timings, each of the intake and exhaust valves 43 and 44 to the values based on a respective intake VVT target phase α_in and exhaust VVT target phase α_ex that takes time to change from an actual phase to a corresponding VVT target phase.

Subsequently, at time t4, the difference ΔTr between the request torque and the actual torque becomes equal to or smaller than the threshold value E, and the change amount of the request torque becomes equal to or smaller than the threshold value F. As a result, the opening and closing timings of each of the intake and exhaust valves change 43 and 44 to the values based on a corresponding initial phase α_in0 and initial phase α_ex0. This leads to a slow change in the opening and closing timings of each of the intake and exhaust valves 43 and 44 ,

As described above, the internal combustion engine controller according to the embodiment deactivates a change in the values of the opening and closing timings of each of the intake and exhaust valves 43 and 44 to coincide with the corresponding intake VVT target phase α_in and exhaust VVT target phase α_ex. This deactivation is performed under the condition that the change amount of the request torque is smaller than the threshold value B in the charging area. At this time, the internal combustion engine controller according to the embodiment also controls the intake and exhaust VVT mechanisms 110 and 111 such that the opening and closing timings of the intake valve 43 coincide with the initial phase α_in0 and the opening and closing times of the exhaust valve 44 coincide with the initial phase α_ex0.

Thus, the internal combustion engine controller according to the embodiment reduces the valve overlap time when the driver does not have a quick acceleration request in the charging area, whereby a return of exhaust air back into the intake passage 41 is reduced. In addition, the internal combustion engine controller according to the embodiment maintains the valve overlap time, which enables outputting of torque corresponding to the driver's request torque, thereby achieving the driver's demand torque. As a result, the internal combustion engine control apparatus according to the embodiment improves drivability while reducing the generation of soot and / or deposits in the charging area.

• (1) eine Übereinstimmung der Öffnungs- und Schließzeitpunkte des Einlassventils 43 mit der Einlass-VVT-Sollphase α_in verursachen und
• (2) eine Übereinstimmung der Öffnungs- und Schließzeitpunkte des Auslassventils 44 mit der Auslass-VVT-Sollphase α_ex verursachen.

The internal combustion engine controller according to the embodiment also controls the intake and exhaust VVT mechanisms 110 and 111 such that the opening and closing timings of the intake valve 43 coincide with the initial phase α_in0 and the opening and closing times of the exhaust valve 44 coincide with the initial phase α_ex0. This control is performed under the condition that the rapid acceleration request is withdrawn in the charging area while the engine control unit 10 the inlet and outlet VVT mechanisms 110 and 111 so energizes that they

• (1) a correspondence of the opening and closing timings of the intake valve 43 with the inlet VVT target phase α_in cause and
• (2) a coincidence of the opening and closing timings of the exhaust valve 44 with the outlet VVT target phase α_ex cause.

As a result, the internal combustion engine control apparatus according to the embodiment improves drivability while reducing the generation of soot and / or deposits in the charging area even when the acceleration request in the charging area is retreated.

It should be noted that this embodiment is an example of the inlet and outlet VVT mechanisms 110 and 111 describes as variable valve actuation mechanisms. It can also be just one of the intake and exhaust VVT mechanisms 110 and 111 be provided as a variable valve actuation mechanism. In this modification, one of the intake or exhaust VVT mechanism increases 110 or 111 the valve overlap time.

An embodiment of the present invention has been disclosed. It is understood that one skilled in the art can change this embodiment without departing from the scope of the present invention. All modifications or equivalents are to be considered as covered by the following claims.

LIST OF REFERENCE NUMBERS

1

vehicle

2

Engine (combustion engine)

6

Turbocharger (loader)

10

Engine control unit

11

Request torque calculation unit

12

control unit

43

intake valve

44

outlet valve

110

Inlet VVT mechanism (variable valve actuation mechanism)

111

Outlet VVT mechanism (variable valve actuation mechanism)

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

• JP 2013-253558 [0002, 0004]

Claims (2)

A control device for an internal combustion engine, comprising a supercharger and a variable valve actuation mechanism for adjusting opening and closing timings of an exhaust valve and / or an intake valve, the control device comprising: a control unit configured to drive the variable valve actuation mechanism such that when the driver requests acceleration in a charging area in which the supercharger performs charging, sets the opening and closing timings to a target opening timing and a target closing timing be extended so that a valve overlap time between the exhaust valve and the intake valve, wherein the control unit is further configured to deactivate the setting of the opening and closing timings to the target opening timing and the target closing timing under the condition that a change amount of the driver-requested torque per unit time is less than a predetermined value in the charging area in that the variable valve actuation mechanism is controlled so as to determine the opening and closing timings: which cause a shortening of the valve overlap time compared to the target opening timing and the target closing timing; and which maintain a valve overlap time which allows a torque corresponding to the requested and output torque. The control device according to claim 1, wherein, under the condition that the acceleration request is withdrawn, while the control unit controls the variable valve operating mechanism such that the opening and closing timings are set to the target opening timing and the target closing timing in the charging area Control unit controls the mechanism for variable valve actuation to determine opening and closing times: which cause a shortening of the valve overlap time compared to the target opening timing and the target closing timing; and which maintain a valve overlap time which allows a torque corresponding to the requested and output torque.

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