JP2016050502A - Control device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of an internal combustion engine which can improve drivability while suppressing the generation of soot and deposits in a supercharging region.SOLUTION: On condition that there is an abrupt acceleration requirement of a driver in a supercharging region, an engine controller controls an intake VVT mechanism and an exhaust VVT mechanism so as to obtain an intake VVT target phase α_in and an exhaust VVT target phase α_ex which increase a valve overlap period. On the other hand, on condition that an increase amount of required torque is smaller than a threshold B in the supercharging region, the engine controller prohibits a change of opening/closing timing to the intake VVT target phase α_in and the exhaust VVT target phase α_ex, decreases the valve overlap period more than that at the intake VVT target phase α_in and the exhaust VVT target phase α_ex, and controls the intake VVT mechanism and the exhaust VVT mechanism so as to obtain initial phases α_in0, α_ex0 for securing the valve overlap period in which torque adapted to the required torque can be outputted.SELECTED DRAWING: Figure 2

Description

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

  2. Description of the Related Art Conventionally, as a control device for an internal combustion engine with a supercharger, an exhaust VVT mechanism and an intake VVT mechanism are controlled to change the valve overlap period of the exhaust valve and the intake valve according to the change rate of the accelerator opening. It is known (see, for example, Patent Document 1).

  In this control device for an internal combustion engine, when the change rate of the accelerator opening is equal to or higher than a threshold at which it can be determined that a rapid acceleration request is required, the closing timing of the exhaust valve and the opening timing of the intake valve are set differently from the case of the normal acceleration request. Also, the valve overlap period is increased at a large change rate. According to the control device for an internal combustion engine, acceleration performance at the time of sudden acceleration can be improved.

JP 2013-253558 A

  However, although the above-described conventional control device for an internal combustion engine improves drivability during rapid acceleration, if the valve overlap period is increased in a supercharging region where supercharging is performed by a supercharger, so-called exhaust emission is increased. The air containing the unburned fuel in the cylinder is likely to be returned to the intake passage side by blowing back. For this reason, in the conventional control device for an internal combustion engine, there is a possibility that soot may be generated due to the exhaust air blow back, or deposits may be generated due to an increase in the inner wall temperature of the intake port.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a control device for an internal combustion engine capable of improving drivability while suppressing generation of soot and deposits in a supercharging region. And

  The present invention is a control device for an internal combustion engine having a supercharger and a variable valve mechanism capable of adjusting an opening / closing timing of at least one of an exhaust valve and an intake valve, wherein supercharging by the supercharger is performed. The variable valve mechanism is controlled so that the opening / closing timing becomes a target opening / closing timing that increases the valve overlap period of the exhaust valve and the intake valve, on condition that the driver has requested acceleration in the supercharging region to be performed The control unit is configured to provide the opening / closing timing to the target opening / closing timing on the condition that an increase amount per unit time of the torque requested by the driver is less than a predetermined value in the supercharging region. Before opening the valve overlap period during which the valve overlap period can be output and the torque corresponding to the required torque can be output. And controlling the variable valve mechanism so as to be opening and closing timing.

  According to the present invention, drivability can be improved while suppressing the occurrence of soot and deposits in the supercharging region.

FIG. 1 is a schematic configuration diagram showing a main part of a vehicle equipped with an internal combustion engine control apparatus according to an embodiment of the present invention. FIG. 2 is a flowchart showing a flow of valve overlap control processing executed by the ECU according to the embodiment of the present invention. FIG. 3 is an example of a timing chart showing the phase change of the intake VVT mechanism and the exhaust VVT mechanism according to the required torque.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. As shown in FIG. 1, a vehicle 1 according to the present embodiment includes an engine 2 as an internal combustion engine and an engine controller 10.

  The engine 2 includes a cylinder block 3 and a cylinder head 4 fastened to the upper part of the cylinder block 3. A cylinder 3a is formed in the cylinder block 3, and a piston 21 that can reciprocate up and down is housed inside the cylinder (hereinafter referred to as "in-cylinder").

  A combustion chamber 5 is provided in the upper part of the cylinder 3a. The combustion chamber 5 is defined by the top surface of the piston 21 and the lower surface of the cylinder head 4. The engine 2 is a so-called four-cycle gasoline engine that performs a series of four strokes including an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke while the piston 21 reciprocates in a cylinder.

  The piston 21 is connected to a crankshaft (not shown) via a connecting rod 21a. The connecting rod 21a converts the reciprocating motion of the piston 21 into the rotational motion of the crankshaft.

  The cylinder head 4 is provided with an injector 30, a spark plug 40, an intake port 41, and an exhaust port 42. The injector 30 is a so-called direct injection type fuel injection valve that directly injects fuel pumped by a fuel pump from a fuel tank (not shown) into the combustion chamber 5. The spark plug 40 is disposed in the cylinder head 4 with an electrode protruding into the combustion chamber 5, and its ignition timing is adjusted by an igniter (not shown).

  The intake port 41 is provided with an intake valve 43 as an intake valve. The intake valve 43 is opened or closed according to the rotation of an intake cam 46 attached to an intake camshaft (not shown). The intake port 41 is opened when the intake valve 43 is opened, and is closed when the intake valve 43 is closed.

  On the other hand, the exhaust port 42 is provided with an exhaust valve 44 as an exhaust valve. The exhaust valve 44 is opened or closed according to the rotation of an exhaust cam 47 attached to an exhaust camshaft (not shown). The exhaust port 42 is opened when the exhaust valve 44 is opened, and is closed when the exhaust valve 44 is closed.

  An intake passage 50 is connected to the intake port 41. The intake passage 50 is a passage for supplying air to the combustion chamber 5 via the intake port 41. The intake passage 50 is provided with an air cleaner 51 for purifying air, a compressor 52 for compressing air, an intercooler 53 for cooling the compressed air, and a throttle valve 54 for adjusting the flow rate of air.

  On the other hand, an exhaust passage 60 is connected to the exhaust port 42. The exhaust passage 60 is a passage for discharging the exhaust discharged from the combustion chamber 5 through the exhaust port 42 to the outside of the vehicle. The exhaust passage 60 is provided with an exhaust turbine 62 driven by an exhaust flow, a catalyst 63 for purifying exhaust, and a muffler (not shown) for silencing.

  The exhaust turbine 62 is connected to the compressor 52. The power of the exhaust turbine 62 driven by the exhaust flow is used as power for the compressor 52 to compress air. The compressor 52 and the exhaust turbine 62 constitute a turbocharger 6 as a supercharger.

  The turbocharger 6 is provided with a wastegate valve 64 that can adjust the exhaust flow to the exhaust turbine 62. The wastegate valve 64 can control the supercharging pressure that is the pressure of the intake air obtained by supercharging the turbocharger 6 by adjusting the exhaust flow to the exhaust turbine 62. The wastegate valve 64 is configured by, for example, an electromagnetic valve, and is opened and closed by the engine controller 10.

  The engine controller 10 includes a microcomputer including, for example, a CPU, a RAM, a ROM, an input / output interface and the like. The CPU uses a temporary storage function of the RAM and performs signal processing according to a program stored in advance in the ROM. Is supposed to do. Various control constants and various maps are stored in advance in the ROM.

  Various sensors such as a pressure sensor 101, a crank angle sensor 102, and an accelerator opening sensor 103 are connected to the input side of the engine controller 10. The pressure sensor 101 detects air supplied to the engine 2 on the downstream side of the throttle valve 54, that is, intake pressure that is the pressure of intake air.

  The crank angle sensor 102 detects the crank angle of the crankshaft by detecting the rotation of a signal rotor attached to the other end of the crankshaft (not shown). The engine controller 10 calculates the engine speed based on the crank angle input from the crank angle sensor 102.

  The accelerator opening sensor 103 detects the amount of depression of an accelerator pedal (not shown) by the driver as the accelerator opening.

  Various devices such as an injector 30, a spark plug 40, a throttle valve 54, an intake VVT mechanism 110 and an exhaust VVT mechanism 111 are connected to the output side of the engine controller 10.

  The intake VVT mechanism 110 adjusts the opening / closing timing of the intake valve 43. The intake VVT mechanism 110 can adjust the opening / closing timing of the intake valve 43 by changing the phase of the intake cam shaft that rotates the intake cam 46 with respect to the movement of the crankshaft, for example, using hydraulic pressure or electromagnetic force. .

  The exhaust VVT mechanism 111 adjusts the opening / closing timing of the exhaust valve 44. The exhaust VVT mechanism 111 can adjust the opening / closing timing of the exhaust valve 44 by changing the phase of the exhaust camshaft that rotates the exhaust cam 47 with respect to the movement of the crankshaft, for example, using hydraulic pressure or electromagnetic force. .

  Driving of the intake VVT mechanism 110 and the exhaust VVT mechanism 111 is controlled by the engine controller 10. In the engine 2 of the present embodiment, the valve overlap period during which both the intake valve 43 and the exhaust valve 44 are opened is increased or decreased through the control of the intake VVT mechanism 110 and the exhaust VVT mechanism 111. The intake VVT mechanism 110 and the exhaust VVT mechanism 111 constitute a variable valve mechanism.

  The engine controller 10 has a function as a required torque calculation unit 11 that calculates a required torque requested by the driver based on the accelerator opening detected by the accelerator opening sensor 103.

  Specifically, the ROM of the engine controller 10 stores a required torque calculation map in which the relationship between the accelerator opening and the required torque is experimentally obtained in advance. Therefore, the engine controller 10 can calculate the required torque by referring to the required torque calculation map based on the accelerator opening.

  The engine controller 10 also has a function as the control unit 12 that controls the intake VVT mechanism 110 and the exhaust VVT mechanism 111 so as to increase or decrease the valve overlap period according to the above-described required torque.

  Specifically, the ROM of the engine controller 10 stores a valve overlap period calculation map in which a valve overlap period corresponding to the required torque is experimentally obtained in advance. Therefore, the engine controller 10 can calculate the valve overlap period by referring to the valve overlap period calculation map based on the required torque.

  Then, the engine controller 10 sets a VVT target phase that is the calculated valve overlap period, and advances or retards the opening / closing timing of the intake valve 43 and the exhaust valve 44 so as to be the VVT target phase. Yes.

  The VVT target phase is set corresponding to the opening / closing timing of each of the intake valve 43 and the exhaust valve 44. Hereinafter, the VVT target phase of the intake valve 43 is referred to as an intake VVT target phase, and the VVT target phase of the exhaust valve 44 is referred to as an exhaust VVT target phase.

  In the present embodiment, such increase / decrease of the valve overlap period is performed according to the presence or absence of an acceleration request from the driver in the supercharging region where supercharging by the turbocharger 6 is performed. Specifically, it is performed by the valve overlap control shown in FIG.

  Next, the valve overlap control executed by the engine controller 10 of the present embodiment will be described with reference to FIG. This valve overlap control is repeatedly executed at predetermined time intervals.

  As shown in FIG. 2, the engine controller 10 determines whether or not the target intake pressure calculated from the required torque is equal to or greater than a threshold value A (step S1). That is, the engine controller 10 determines whether or not the operation region of the turbocharger 6 is in the supercharging region.

  Here, the engine controller 10 can calculate the target intake pressure from the required torque by experimentally obtaining the relationship between the required torque and the target intake pressure in advance and referring to the intake pressure map stored in the ROM. it can.

  The above-described threshold A is a value that varies based on the driving state of the engine 2 such as the engine speed, engine load, engine torque, torque change rate, and intake pressure. The engine controller 10 can set the threshold A by referring to a map in which the relationship between the driving state of the engine 2 and the threshold A is experimentally obtained in advance.

  If the engine controller 10 determines that the target intake pressure is not equal to or greater than the threshold value A, it determines that the target intake pressure is not in the supercharging region, executes normal control (step S8), and ends the valve overlap control. In the normal control, the engine controller 10 controls the intake VVT mechanism 110 and the exhaust VVT mechanism 111 so that the opening / closing timing of the intake valve 43 and the exhaust valve 44 becomes the normal opening / closing timing in the non-supercharging region.

  On the other hand, when it is determined that the target intake pressure is equal to or higher than the threshold A, the engine controller 10 determines whether the required torque is increased and the change amount of the required torque is equal to or higher than the threshold B as a predetermined value. (Step S2).

In this process, the engine controller 10 determines whether or not there has been a driver's acceleration request, in this embodiment, a rapid acceleration request. Here, the change amount of the required torque is the change amount of the required torque per unit time, and in this embodiment, indicates the increase amount of the required torque per unit time.
Further, the threshold value B described above is a value that varies based on the driving state of the engine 2. The engine controller 10 can set the threshold B by referring to a map in which the relationship between the driving state of the engine 2 and the threshold B is experimentally obtained in advance.

  If the engine controller 10 determines that the required torque has increased and the amount of change in the required torque is greater than or equal to the threshold value B, the engine controller 10 determines that there is a sudden acceleration request by the driver, and the intake valve 43 and the exhaust valve 44 The opening and closing timings of the intake valve 43 and the exhaust valve 44 are advanced and retarded until the opening and closing timings of the engine become the intake VVT target phase and the exhaust VVT target phase, respectively (step S3).

  Specifically, when the engine controller 10 determines that there is a sudden acceleration request, the engine controller 10 advances more than before the sudden acceleration request so that the valve overlap period is longer than before the sudden acceleration request is made. The intake VVT target phase α_in and the exhaust VVT target phase α_ex retarded from before the sudden acceleration request is made are set as the target opening / closing timing.

  Then, the engine controller 10 advances and retards the opening / closing timing of the intake valve 43 and the exhaust valve 44 until the intake VVT target phase α_in and the exhaust VVT target phase α_ex are reached based on the time constant τ1. The exhaust VVT mechanism 111 is controlled.

  Here, the time constant τ 1 is a value that varies based on the driving state of the engine 2. The engine controller 10 can set the time constant τ1 by referring to a map in which the relationship between the driving state of the engine 2 and the time constant τ1 is experimentally obtained in advance. The time constant τ1 is a value that can change the opening / closing timing of the intake valve 43 and the exhaust valve 44 in a stepwise manner, that is, relatively slowly rather than slowly.

  As described above, the engine controller 10 determines that the intake VVT target phase in which the opening / closing timing of the intake valve 43 and the exhaust valve 44 increases the valve overlap period on the condition that the driver has requested rapid acceleration in the supercharging region. The intake VVT mechanism 110 and the exhaust VVT mechanism 111 are controlled so as to be α_in and the exhaust VVT target phase α_ex.

  On the other hand, if the engine controller 10 determines in step S2 that the required torque has increased and the amount of change in the required torque is not greater than or equal to the threshold value B, the engine controller 10 determines that there is no sudden acceleration request from the driver, and the intake valve 43 and the opening / closing timing of the exhaust valve 44 are changed to the initial phases α_in0 and α_ex0 based on the time constant τ2 (step S5).

  Here, the above-described initial phase α_in0 is the opening / closing timing of the intake valve 43 that reduces the valve overlap period as compared with the intake VVT target phase α_in, and ensures a valve overlap period in which a torque corresponding to the required torque can be output. This is the opening / closing timing of the intake valve 43.

  Further, the initial phase α_ex0 described above is an opening / closing timing of the exhaust valve 44 that reduces the valve overlap period as compared with the exhaust VVT target phase α_ex, and an exhaust that secures a valve overlap period that can output a torque corresponding to the required torque. It is the opening / closing timing of the valve 44.

  The time constant τ2 described above is a value that varies based on the driving state of the engine 2. The engine controller 10 can set the time constant τ2 by referring to a map in which the relationship between the driving state of the engine 2 and the time constant τ2 is experimentally obtained in advance. The time constant τ2 is set to a value larger than τ1 described above. Therefore, the engine controller 10 changes the opening / closing timing of the intake valve 43 and the exhaust valve 44 more slowly than in the case based on the time constant τ1.

  As described above, the engine controller 10 sets the intake VVT target phase α_in and the exhaust VVT target phase α_ex as shown in step S3 to the condition that the change amount of the required torque is less than the threshold value B in the supercharging region. The intake VVT mechanism 110 and the exhaust VVT mechanism 111 are controlled so that the opening / closing timing of the intake valve 43 and the exhaust valve 44 is prohibited and the opening / closing timing of the intake valve 43 and the exhaust valve 44 becomes the initial phases α_in0 and α_ex0.

  Further, when the opening / closing timing of the intake valve 43 and the exhaust valve 44 is controlled to the initial phases α_in0 and α_ex0 as described above, the engine controller 10 adjusts the throttle valve 54, the wastegate valve 64 and the like to adjust the turbocharger 6. The supercharging pressure is controlled to a supercharging pressure capable of realizing the required torque.

  Further, after the process of step S3, the engine controller 10 determines whether or not the difference ΔTr between the required torque and the actual torque is equal to or less than the threshold value E and the change amount of the required torque is equal to or less than the threshold value F (step S4). ).

  The above-described threshold value E is a threshold value for determining whether or not ΔTr has decreased to such an extent that it can be determined that the actual torque that is the actual torque satisfies the required torque requested by the driver. Further, the above-described threshold value F is a threshold value for determining whether or not the amount of change in the required torque has decreased to such an extent that it can be determined that there has been no sudden acceleration request from the driver.

  The threshold value E and the threshold value F are values that vary based on the driving state of the engine 2. The engine controller 10 can set the threshold E and the threshold F by referring to a map in which the relationship between the driving state of the engine 2 and these thresholds is experimentally obtained in advance.

  In the process of step S4, the engine controller 10 determines whether or not the rapid acceleration request by the driver has ended. That is, the engine controller 10 determines whether it is steady running with a constant accelerator opening, or slow acceleration or slow deceleration with a small amount of change in the accelerator opening.

  If the engine controller 10 determines that ΔTr is equal to or less than the threshold value E and the amount of change in the required torque is not equal to or less than the threshold value F, the engine controller 10 determines that there is still a rapid acceleration request from the driver, and again in step S3. Repeat the process.

  On the other hand, when the engine controller 10 determines that ΔTr is equal to or less than the threshold value E and the amount of change in the required torque is equal to or less than the threshold value F, the engine controller 10 determines that the rapid acceleration request by the driver has disappeared, and Step S5 is performed.

  That is, the engine controller 10 controls the intake VVT mechanism 110 and the exhaust VVT mechanism 111 so that the opening / closing timing of the intake valve 43 and the exhaust valve 44 becomes the intake VVT target phase α_in and the exhaust VVT target phase α_ex in the supercharging region. If there is no sudden acceleration request, the process of step S5 is performed.

  Specifically, the engine controller 10 changes the opening / closing timing of the intake valve 43 and the exhaust valve 44 to the initial phases α_in0 and α_ex0 corresponding to the required torque based on the time constant τ2.

  Next, the engine controller 10 determines whether or not the target intake pressure is equal to or less than the threshold value H (step S6). That is, the engine controller 10 determines whether or not the supercharging region has ended, that is, whether or not the operating region of the turbocharger 6 is in the non-supercharging region.

  The threshold value H described above is a value that varies based on the driving state of the engine 2. The engine controller 10 can set the threshold value H by referring to a map in which the relationship between the driving state of the engine 2 and the threshold value H is experimentally obtained in advance.

  If the engine controller 10 determines that the target intake pressure is not less than or equal to the threshold value H, the engine controller 10 returns to step S2 and repeats the subsequent processing.

  On the other hand, when the engine controller 10 determines that the target intake pressure is equal to or less than the threshold value H, the opening / closing timing of the intake valve 43 and the exhaust valve 44 is determined based on the time constant τ3, the normal intake VVT phase β_in, the exhaust VVT. Intake VVT mechanism 110 and exhaust VVT mechanism 111 are controlled to advance and retard until phase β_ex is reached (step S7).

  Here, the time constant τ 3 is a value that varies based on the driving state of the engine 2. The engine controller 10 can set the time constant τ3 by referring to a map in which the relationship between the driving state of the engine 2 and the time constant τ3 is experimentally obtained in advance. The time constant τ3 is set to a value larger than τ1 described above. Therefore, the engine controller 10 changes the opening / closing timing of the intake valve 43 and the exhaust valve 44 more slowly than in the case based on the time constant τ1.

  Next, the engine controller 10 shifts to normal control in the non-supercharging region (step S8), and ends the valve overlap control.

  Next, with reference to FIG. 3, the operation of the control apparatus for an internal combustion engine according to the present embodiment will be described.

  As shown in FIG. 3, at the time of steady running until time t1, the operation region of the turbocharger 6 is the non-supercharging region, and the opening / closing timing of the intake valve 43 and the exhaust valve 44 is the normal intake VVT phase β_in, exhaust VVT phase β_ex.

  Thereafter, when the required torque increases in response to the driver's request for slow acceleration at time t1, the operating region of the turbocharger 6 shifts from the non-supercharging region to the supercharging region. At this time, the opening / closing timing of the intake valve 43 and the exhaust valve 44 is maintained at the normal intake VVT phase β_in and the exhaust VVT phase β_ex.

  Subsequently, after the slow acceleration is completed at time t2, when the required torque increases rapidly in response to the driver's request for rapid acceleration at time t3, the change amount of the required torque becomes equal to or greater than the threshold value B. As a result, the opening / closing timings of the intake valve 43 and the exhaust valve 44 are changed from the normal intake VVT phase β_in and the exhaust VVT phase β_ex to the intake VVT target phase α_in and the exhaust VVT target phase α_ex. Changes in the opening / closing timing of the intake valve 43 and the exhaust valve 44 at this time are stepwise, and are immediately changed to the intake VVT target phase α_in and the exhaust VVT target phase α_ex.

  At this time, since the opening / closing timing of the intake valve 43 and the exhaust valve 44 is suddenly changed to the intake VVT target phase α_in and the exhaust VVT target phase α_ex, the actual phase that is the actual VVT phase may overshoot with respect to the VVT target phase. There is. In this case, there is a concern about the influence on OBD (On Board Diagnosis) diagnosis.

  Specifically, when the above-described overshoot occurs, the OBD determination time may elapse before the actual phase shifts to the VVT target phase. If the OBD determination time elapses before the actual phase shifts to the VVT target phase, it is determined by the OBD diagnosis that the intake VVT mechanism 110 and the exhaust VVT mechanism 111 are defective.

  In the present embodiment, in order to avoid such a failure determination, when the opening / closing timing of the intake valve 43 and the exhaust valve 44 is suddenly changed to the intake VVT target phase α_in and the exhaust VVT target phase α_ex, the determination of OBD is performed. The time is changed temporarily. The OBD determination time takes time until the actual phase changes to the VVT target phase when the opening / closing timing of the intake valve 43 and the exhaust valve 44 is suddenly changed to the intake VVT target phase α_in and the exhaust VVT target phase α_ex. However, the determination time is changed to such a long determination time that no failure determination is made.

  Next, at time t4, when the difference ΔTr between the required torque and the actual torque is equal to or less than the threshold value E and the amount of change in the required torque is equal to or less than the threshold value F, the opening / closing timings of the intake valve 43 and the exhaust valve 44 correspond to the required torque. The initial phases α_in0 and α_ex0 are changed. Changes in the opening / closing timing of the intake valve 43 and the exhaust valve 44 at this time are slow.

  As described above, the control device for the internal combustion engine according to the present embodiment provides that the intake valve 43 and the control unit are configured on the condition that the increase amount per unit time of the torque requested by the driver is less than the threshold value B in the supercharging region. Changing the opening / closing timing of the exhaust valve 44 to the intake VVT target phase α_in and the exhaust VVT target phase α_ex is prohibited. At this time, the control device for the internal combustion engine according to the present embodiment controls the intake VVT mechanism 110 and the exhaust VVT mechanism 111 so that the opening / closing timings of the intake valve 43 and the exhaust valve 44 become the initial phases α_in0 and α_ex0.

  For this reason, the control device for an internal combustion engine according to the present embodiment reduces the valve overlap period when there is no driver's rapid acceleration request in the supercharging region, so that the exhaust gas is blown back to the intake port 41. Can be suppressed. Further, at this time, the valve overlap period in which a torque commensurate with the driver's required torque can be output is ensured, so that the driver's required torque can be ensured. As a result, the control apparatus for an internal combustion engine according to the present embodiment can improve drivability while suppressing the generation of soot and deposits in the supercharging region.

  In addition, the control apparatus for an internal combustion engine according to the present embodiment includes the intake VVT mechanism 110 and the exhaust VVT target phase α_in and the exhaust VVT target phase α_ex so that the opening / closing timings of the intake valve 43 and the exhaust valve 44 become the intake VVT target phase α_ex in the supercharging region. The intake VVT mechanism 110 and the exhaust VVT mechanism 111 are set so that the opening / closing timing of the intake valve 43 and the exhaust valve 44 becomes the initial phases α_in0 and α_ex0 on condition that the acceleration request is lost when the exhaust VVT mechanism 111 is controlled. Control. Thereby, the control apparatus for an internal combustion engine according to the present embodiment can improve drivability while suppressing the generation of soot and deposit even when the acceleration request is lost in the supercharging region.

  In the present embodiment, an example in which the intake VVT mechanism 110 and the exhaust VVT mechanism 111 are provided as variable valve mechanisms has been described. However, the present invention is not limited to this, and for example, the intake VVT mechanism 110 and exhaust VVT are provided as variable valve mechanisms. The structure which provided either one of the mechanisms 111 may be sufficient. In this case, the valve overlap period is increased or decreased by either the intake VVT mechanism 110 or the exhaust VVT mechanism 111.

  Although the embodiments of the present invention have been disclosed as described above, it is obvious that those skilled in the art can make changes without departing from the scope of the present invention. All such modifications and equivalents are intended to be included in the following claims.

1 vehicle 2 engine (internal combustion engine)
6 Turbocharger (supercharger)
DESCRIPTION OF SYMBOLS 10 Engine controller 11 Required torque calculation part 12 Control part 43 Intake valve (intake valve)
44 Exhaust valve (exhaust valve)
110 Intake VVT mechanism (Variable valve mechanism)
111 Exhaust VVT mechanism (variable valve mechanism)

Claims (2)

A control device for an internal combustion engine having a supercharger and a variable valve mechanism capable of adjusting an opening / closing timing of at least one of an exhaust valve and an intake valve,
In the supercharging region where supercharging by the supercharger is performed, the opening / closing timing becomes the target opening / closing timing for increasing the valve overlap period of the exhaust valve and the intake valve, on condition that the driver has requested acceleration. A control unit for controlling the variable valve mechanism,
The control unit prohibits the change of the opening / closing timing to the target opening / closing timing on the condition that an increase amount per unit time of the torque requested by the driver is less than a predetermined value in the supercharging region. The variable valve mechanism is set to the opening / closing timing for reducing the valve overlap period from the target opening / closing time, and to ensure the valve overlapping period in which a torque commensurate with the required torque can be output. A control device for an internal combustion engine, characterized by controlling. In the supercharging region, the control unit controls the variable valve mechanism so that the opening / closing timing becomes the target opening / closing timing. The variable valve mechanism is controlled so as to be the opening / closing timing for reducing the valve overlap period and ensuring the valve overlap period during which a torque commensurate with the required torque can be output. The control device for an internal combustion engine according to claim 1.

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