JP2011220256A - Internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an internal combustion engine that suppresses deterioration in combustion caused by bypassing a turbine of a turbocharger.SOLUTION: The internal combustion engine includes: an internal combustion engine body 50; the turbocharger 40 where a turbine 42 is provided on one side of an exhaust pipe connected to the internal combustion body 50; a ternary catalyst 22 that is disposed down the stream of the turbine 42; a bypass passage 43a that bypasses the turbine 42 and directly flows exhaust into the ternary catalyst 22; a valve 43 that opens and closes the bypass passage 43a and an ECU1A that increases a cylindrical internal pressure when the bypass passage 43a is opened by the valve 43 and the exhaust is directly flowed in the ternary catalyst 22.

Description

  The present invention relates to an internal combustion engine having a turbocharger.

Internal combustion engines having a turbocharger are known. For example, Patent Document 1 discloses disposing a catalyst downstream of a turbocharger. The catalyst purifies the exhaust gas flowing from the turbocharger.
Patent Document 1 also discloses a bypass passage that bypasses the turbine of the turbocharger and allows exhaust gas to flow into the catalyst. The bypass passage bypasses the turbocharger turbine when warming up the catalyst quickly.

  A correlation between the cylinder pressure in the combustion chamber of the internal combustion engine and the turbocharging pressure of the turbocharger is also known. For example, Patent Document 2 discloses that in an internal combustion engine that does not bypass the turbocharger, when the cylinder pressure in the combustion chamber is lower than a predetermined value, the pressure of the turbocharger is increased so as to increase the pressure of the intake air sucked into the combustion chamber. It is suggested to control the supercharging pressure.

JP 2002-364503 A JP 2004-19462 A

  By the way, when bypassing the turbine of the turbocharger, the exhaust gas flows into both the turbocharger and the bypass passage. For this reason, the space through which the exhaust flows increases, and the exhaust pressure may decrease. In this case, the supercharging pressure of the turbocharger also decreases, and the in-cylinder pressure in the combustion chamber decreases. When the in-cylinder pressure in the combustion chamber decreases, the in-cylinder temperature decreases. Therefore, when the exhaust gas bypasses the turbocharger turbine, combustion in the combustion chamber may be worse than when the exhaust gas bypasses the turbine.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an internal combustion engine that suppresses combustion deterioration associated with bypassing a turbine of a turbocharger.

In order to solve the above problems, an internal combustion engine of the present invention includes an internal combustion engine body, a turbocharger provided with a turbine on the exhaust pipe side connected to the internal combustion engine body, and a catalyst disposed downstream of the turbine. And a bypass passage for bypassing the turbine and allowing the exhaust to flow directly into the catalyst, an opening / closing means for opening and closing the bypass passage, and the bypass passage being opened by the opening / closing means to increase the in-cylinder pressure when the exhaust flows directly into the catalyst. Boosting means.
According to this configuration, the in-cylinder pressure can be increased when the bypass passage is opened by the opening / closing means.

Further, the boosting means in the present invention increases the in-cylinder pressure when the in-cylinder pressure when the bypass passage is opened by the opening / closing means is lower than the in-cylinder pressure when the bypass passage is closed by the opening / closing means. It is a feature.
According to this configuration, the in-cylinder pressure can be increased when the bypass passage is opened by the opening / closing means and the in-cylinder pressure is reduced.

Further, the present invention includes storage means for storing an exhaust deterioration region caused by the operation state of the internal combustion engine body when the bypass passage is opened by the opening / closing means, and the boosting means is provided in the deterioration region where the operation state is predetermined. When included, the in-cylinder pressure is increased.
According to this configuration, the in-cylinder pressure can be increased when the bypass passage is opened by the opening / closing means and when the operating state is included in the predetermined deterioration region.

Further, the boosting means in the present invention is characterized in that when the turbocharger is a variable nozzle turbo, the in-cylinder pressure is increased by controlling the variable nozzle provided in the variable nozzle turbo in a closing direction. .
According to this configuration, when the turbocharger is a variable nozzle turbo, the in-cylinder pressure can be increased by controlling the variable nozzle provided in the variable nozzle turbo in the closing direction. .

Further, the boosting means in the present invention increases the in-cylinder pressure by increasing the supercharging pressure by increasing the rotational speed of the electric motor provided in the electric assist turbo when the turbocharger is an electric assist turbo. It is characterized by letting.
According to this configuration, when the turbocharger is an electric assist turbo, the in-cylinder pressure can be increased by increasing the supercharging pressure by increasing the rotational speed of the electric motor provided in the electric assist turbo. it can.

Further, the boosting means in the present invention is characterized in that the ignition condition of the ignition device is changed when the internal combustion engine body is a gasoline engine.
According to this configuration, when the internal combustion engine body is a gasoline engine, the ignition condition of the ignition device can be changed.

Further, the boosting means in the present invention is characterized in that the injection condition of the fuel injection device is changed when the internal combustion engine body is a diesel engine.
According to this configuration, when the internal combustion engine body is a diesel engine, the injection conditions of the fuel injection device can be changed.

  Further, the pressure increasing means in the present invention may increase the in-cylinder pressure by changing the phase and / or the operating angle of the intake valve to the side where the intake air amount increases, or to the side where the exhaust pressure increases. The in-cylinder pressure may be increased by changing the phase and / or operating angle of the exhaust valve. Even if it does in this way, the fall of a cylinder internal pressure can be suppressed.

Further, the pressure increasing means in the present invention may increase the in-cylinder pressure by controlling the exhaust throttle valve provided downstream of the catalyst to the closing side.
According to this configuration, the exhaust throttle valve is controlled to the closed side, so that a decrease in exhaust pressure is suppressed, and further, a decrease in supercharging pressure is suppressed. Therefore, a decrease in in-cylinder pressure can be suppressed.

  ADVANTAGE OF THE INVENTION According to this invention, the combustion deterioration accompanying bypassing the turbine of a turbocharger is suppressed.

It is an example of an internal combustion engine. It is a graph which shows the relationship between an EGR rate, exhaust pressure, and intake pressure. It is an example of the graph which shows the relationship between a crank angle and in-cylinder pressure. It is an example of the control map used by a pressure | voltage rise process. It is a flowchart which shows an example of the operation | movement of the pressure | voltage rise process by CPU. It is an example of sectional drawing of a variable nozzle turbo. It is an example of an electrically assisted turbo. It is a flowchart which shows another example of the operation | movement of the pressure | voltage rise process by CPU. It is another example of an internal combustion engine. It is a flowchart which shows an example of the pressure | voltage rise process which concerns on 2nd Example.

  Embodiments according to the present invention will be described below with reference to the drawings.

FIG. 1 is an example of an internal combustion engine 100.
The ECU 1A and the internal combustion engine 100 shown in FIG. 1 are provided in a vehicle (not shown). The internal combustion engine 100 includes an intake system 10, an exhaust system 20, a fuel injection system 30, a turbocharger 40, and an internal combustion engine body 50.

The intake system 10 includes an air cleaner 11, an air flow meter 12, an intercooler 13, an electric throttle 14, a surge tank 15, an intake manifold 16, an intake port 52a, and an intake pipe appropriately disposed between these components.
The air cleaner 11 filters the intake air supplied to the internal combustion engine body 50.
The air flow meter 12 measures the amount of intake air. The air flow meter 12 outputs a signal corresponding to the intake air amount.
The intercooler 13 cools the intake air compressed by the turbocharger 40.
The electric throttle 14 adjusts the intake flow rate supplied to the internal combustion engine body 50 under the control of the ECU 1A. The electric throttle 14 includes a throttle valve 14a, an electric motor (not shown), a throttle opening sensor, and the like.
The surge tank 15 temporarily stores intake air.
The intake manifold 16 distributes intake air from the surge tank 15 to each cylinder of the internal combustion engine body 50.

The exhaust system 20 includes an exhaust port 52b, an exhaust manifold 21, a three-way catalyst 22, a silencer (not shown), and an exhaust pipe appropriately disposed between these components.
The exhaust manifold 21 joins the exhaust from each cylinder. The exhaust manifold 21 collects the exhaust passage branched according to each cylinder into one exhaust passage on the downstream side.
The three-way catalyst 22 purifies the exhaust gas. The three-way catalyst 22 oxidizes hydrocarbons HC and carbon monoxide CO and reduces nitrogen oxides NOx.

The fuel injection system 30 includes a fuel injection valve 31, a fuel injection pump 32, a fuel tank 33, and the like.
The fuel injection valve 31 injects fuel. The fuel injection valve 31 is opened at an appropriate injection timing and injects fuel under the control of the ECU 1A. The fuel injection amount is adjusted by the length of the valve opening period until the fuel injection valve 31 is closed under the control of the ECU 1A. The fuel injection valve 31 is disposed in the intake manifold 16 with an injection hole protruding from the intake passage.
The fuel injection pump 32 pressurizes the fuel to generate an injection pressure. The fuel injection pump 32 adjusts the injection pressure to an appropriate injection pressure under the control of the ECU 1A.

  The turbocharger 40 includes a compressor 41, a turbine 42, and an opening / closing valve 43 as an opening / closing means. The turbocharger 40 is disposed such that a compressor portion that houses a compressor 41 is interposed in the intake system 10 and a turbine portion that houses a turbine 42 is interposed in the exhaust system 20. The turbocharger 40 may be a variable nozzle turbo or an electric assist turbo.

The compressor 41 and the turbine 42 are connected by a rotating shaft. When the turbine 42 is driven by exhaust gas, the compressor 41 is driven via the rotating shaft. As a result, the intake air is compressed.
The open / close valve 43 opens and closes the bypass passage 43a. When the opening / closing valve 43 is opened under the control of the ECU 1A, the exhaust gas bypasses the turbine 42 through the bypass passage 43a and flows directly into the three-way catalyst 22.

  The internal combustion engine body 50 includes a cylinder block 51, a cylinder head 52, a piston 53, an intake valve 54, an exhaust valve 55, a spark plug 56, a connecting rod 57, a crankshaft 58, a crank angle sensor 60, and an intake side VVT (Variable Valve Timing). 61, an exhaust side VVT 62 and an in-cylinder pressure sensor 63 are provided.

  The internal combustion engine body 50 shown in the present embodiment is an in-line 4-cylinder supercharged gasoline engine. However, the present invention is not limited to this, and the internal combustion engine body 50 may have other appropriate cylinder arrangement structure and number of cylinders, and the internal combustion engine body 50 may be a so-called diesel engine, direct injection gasoline engine, or lean burn engine. Besides, other appropriate internal combustion engines may be used. Further, in FIG. 1, the main part of the cylinder 51a is shown as a representative of the internal combustion engine main body 50, but the other cylinders have the same structure.

  The cylinder block 51 is formed with a substantially cylindrical cylinder 51a. A piston 53 is accommodated in the cylinder 51a. A cylinder head 52 is fixed to the upper surface of the cylinder block 51. The combustion chamber 59 is formed as a space surrounded by the cylinder block 51, the cylinder head 52 and the cylinder 53.

  The cylinder head 52 is formed with an intake port 52 a for guiding intake air to the combustion chamber 59 and an exhaust port 52 b for exhausting the burned gas from the combustion chamber 59. An intake pipe is connected to the intake port 52a. An exhaust pipe is connected to the exhaust port 52b. The cylinder head 52 is provided with an intake valve 54 for opening and closing the flow path of the intake port 52a and an exhaust valve 55 for opening and closing the flow path of the exhaust port 52b.

The spark plug 56 is disposed in the cylinder head 52 with an electrode protruding substantially at the center above the combustion chamber 59.
The piston 53 is connected to the crankshaft 58 via a connecting rod 57. The reciprocating motion of the piston 53 is converted into rotational motion by the crankshaft 58.
The crank angle sensor 60 obtains an output pulse proportional to the engine speed.
The in-cylinder pressure sensor 63 detects the pressure in the combustion chamber 59 and outputs the detected pressure to the ECU 1A.

  The intake side VVT (hereinafter simply referred to as InVVT) 61 changes the valve timing of the intake valve 54. The InVVT 61 has an intake side camshaft and a hydraulic device (not shown). The InVVT 61 changes the phase of the intake camshaft with respect to the phase of the crankshaft 58 by a hydraulic device under the control of the ECU 1A. Thereby, the valve timing of the intake valve 54 is changed. The hydraulic device employs a mechanism capable of continuously changing the phase of the intake camshaft.

  An exhaust side VVT (hereinafter simply referred to as ExVVT) 62 changes the valve timing of the exhaust valve 55. The ExVVT 62 has an exhaust side camshaft and a hydraulic device (not shown). The ExVVT 62 can also continuously change the valve timing of the exhaust valve 55 under the control of the ECU 1A, similarly to the InVVT 61.

  Instead of InVVT 61 and ExVVT 62, for example, a variable valve mechanism that can change the valve lift amount with the valve timing, such as VVTL-i (VVT and Lift intelligent system), may be applied. In this embodiment, the variable valve mechanism is realized by the InVVT 61 and the ExVVT 62.

  The ECU 1A functions as a boosting unit of the present invention, and is configured with a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like (not shown). A computer (hereinafter simply referred to as a microcomputer) and an input / output circuit are included.

  The ECU 1A mainly controls the internal combustion engine body 50. In this embodiment, the ECU 1A controls the fuel injection valve 31, the turbine 42, the opening / closing valve 43, the spark plug 56, the InVVT 61, the ExVVT 62, and the like. Various sensors such as a fuel injection valve 31, a crank angle sensor 60, and an in-cylinder pressure sensor 63 are connected to the ECU 1A. The ECU 1A is connected to various control objects such as an electric throttle 14, a fuel injection valve 31, a spark plug 56, and InVVT 61 and ExVVT 62 via a drive circuit. These connections are omitted as appropriate for convenience of illustration. The ROM stores a program describing various processes (for example, boosting process) executed by the CPU, various control maps, and the like.

  Subsequently, a decrease in exhaust pressure, intake pressure and in-cylinder pressure accompanying opening and closing of the bypass passage 43a will be described with reference to FIGS.

FIG. 2 is a graph showing the relationship between the EGR rate, the exhaust pressure, and the intake pressure. The EGR rate, the exhaust pressure, and the intake pressure are examples of operating states.
A graph indicated by a broken line indicates a relationship between the EGR rate, the exhaust pressure, and the intake pressure when the on-off valve 43 is closed (in FIG. 2, when not bypassed, the same applies in FIG. 3). A graph indicated by a solid line shows a relationship between the EGR rate, the exhaust pressure, and the intake pressure when the opening / closing valve 43 is opened (in FIG. 2, when bypassed; the same applies in FIG. 3).

  As shown in FIG. 2, when the opening / closing valve 43 is opened from the state where the opening / closing valve 43 is closed, the exhaust pressure and the intake pressure are reduced. This is because when the opening / closing valve 43 is opened, the exhaust gas passes through the bypass passage 43a, so that the exhaust pressure is weakened. As a result, the rotational force of the turbine 42 is weakened, and the rotational force of the compressor 41 is also weakened. Therefore, the supercharging pressure is also reduced, and the intake pressure is also reduced.

FIG. 3 is an example of a graph showing the relationship between the crank angle and the in-cylinder pressure. Crank angle and in-cylinder pressure are examples of operating conditions.
A graph indicated by a broken line indicates a relationship between the crank angle and the in-cylinder pressure when the on-off valve 43 is closed. The graph shown by the solid line shows the relationship between the crank angle and the in-cylinder pressure when the on-off valve 43 is opened.

  When the opening / closing valve 43 is opened from the state where the opening / closing valve 43 is closed, the supercharging pressure is lowered as described above, and the intake pressure is also lowered. As a result, the amount of fuel gas flowing into the combustion chamber 59 is reduced. For this reason, the fuel gas which exists in the combustion chamber 59 decreases, and a cylinder pressure falls. When the in-cylinder pressure decreases, the combustion in the combustion chamber 59 deteriorates.

  Therefore, in this embodiment, the in-cylinder pressure is increased by increasing the exhaust pressure at the time of bypass as indicated by the white arrow A shown in FIG. The ECU 1A is caused to perform a pressure increasing process for raising the pressure to the cylinder pressure at that time. By such pressure increase processing, deterioration of combustion in the combustion chamber 59 is suppressed.

FIG. 4 is an example of a control map used in the boosting process.
The control map shown in FIG. 4 shows the relationship between the engine speed and the engine load as the operating state. As the engine load, for example, there is a fuel injection amount. The engine speed is calculated based on output pulses generated from the crank angle sensor 60.

A region surrounded by a vertical axis, a horizontal axis, and a broken line indicates a bypass region. The bypass region is a region specified by the relationship between the engine speed and the engine load when the opening / closing valve 43 is opened.
The exhaust deterioration region is a part of the bypass region, and is a region for determining whether or not the combustion in the combustion chamber 59 has deteriorated. This area is attributed to the operating state. The exhaust deterioration region is determined in advance from the bypass region based on design values and actual measurement values. Accordingly, when the value of the engine speed and the engine load when the opening / closing valve 43 is opened is included in the exhaust deterioration region, it is determined that the combustion in the combustion chamber 59 has deteriorated, and the ECU 1A Is started.

  FIG. 5 is a flowchart showing an example of the operation of the boosting process by the CPU, FIG. 6 is an example of a sectional view of the variable nozzle turbo, and FIG. 7 is an example of the electric assist turbo. The flowchart is executed when the ECU 1A detects a decrease in the in-cylinder pressure.

  The CPU determines whether or not the bypass passage 43a is open (step S1). Specifically, the CPU communicates with the opening / closing valve 43 and determines whether or not the bypass passage 43a is in an open state. If the in-cylinder pressure is reduced but the bypass passage 43a is not open (step S1: NO), the process is terminated.

  When the CPU determines that the bypass passage 43a is open (step S1: YES), the CPU then determines whether or not the current operation state is included in the exhaust deterioration region (step S2). Specifically, the engine speed is calculated based on the output pulse generated by the crank angle sensor 60, and whether or not a position specified by the engine speed and the fuel injection amount as the engine load is included in the exhaust deterioration region. Determine whether.

  When the CPU determines that the current operation state is included in the exhaust deterioration region (step S2: YES), when the turbocharger 40 is a variable nozzle turbo, the CPU changes the variable nozzle to the closed side (step S3). . Specifically, as shown in FIG. 6A, when the variable nozzle 42a of the variable nozzle turbo is open, the CPU controls the variable nozzle 42a to be closed as shown in FIG. 6B. . Thereby, the supercharging efficiency is increased and the decrease in the supercharging pressure is suppressed. When the turbocharger 40 is an electric assist turbo, as shown in FIG. 7, the rotational speed of the electric assist turbo is assisted by the assist (rotation assist function) of the electric motor 43 based on a control signal from the ECU 1A. Increase the boost pressure to the target pressure. Such a process can also suppress a decrease in supercharging pressure.

  When the CPU completes the process of step S3, it next changes the ignition condition and the fuel injection condition (step S4). For example, if the internal combustion engine body 50 is a gasoline engine, an example of changing the ignition condition is a condition change for delaying the ignition timing. Further, for example, if the internal combustion engine body 50 is a diesel engine, examples of changing the fuel injection conditions include changing the conditions such as increasing the fuel injection timing, widening the injection pattern, and increasing the injection amount. Thereby, the fall of the supercharging pressure accompanying having changed the variable nozzle to the closed side etc. can be suppressed, and the reduction | decrease of the quantity of the fuel gas which flows into the combustion chamber 59 can also be suppressed. Accordingly, a decrease in in-cylinder pressure is also suppressed, and deterioration of combustion in the combustion chamber 59 is also suppressed.

  FIG. 8 is a flowchart showing another example of the operation of the boosting process by the CPU. Note that the processing in steps S11 and S12 shown in FIG. 8 is the same as the processing in steps S1 and S2 shown in FIG.

  In FIG. 8, in the process of step S13, the CPU changes the drive system of the intake valve and the exhaust valve. Specifically, the CPU changes the phase and operating angle of the intake valve so that the intake air amount increases. Further, the CPU changes the phase and operating angle of the exhaust valve so that the exhaust pressure increases. These changes may be made simultaneously. Even with such a change, a decrease in the in-cylinder pressure is suppressed, and deterioration of combustion can be suppressed.

Next, a second embodiment of the present invention will be described with reference to FIGS.
FIG. 9 shows another example of the internal combustion engine 100. In addition, the same code | symbol is attached | subjected to the structure similar to the structure of the internal combustion engine 100 shown in FIG. 1, and the description is abbreviate | omitted.

The internal combustion engine 100 shown in FIG. 9 is different from the internal combustion engine 100 shown in FIG. 1 in that it further includes an exhaust throttle valve 23 and an exhaust pressure sensor 24. Both the exhaust throttle valve 23 and the exhaust pressure sensor 24 are connected to the ECU 1A.
The exhaust throttle valve 23 is provided downstream of the three-way catalyst 22. The exhaust throttle valve 23 adjusts the exhaust flow rate exhausted from the internal combustion engine body 50 under the control of the ECU 1A. When the exhaust throttle valve 23 is throttled, the exhaust pressure increases.
The exhaust pressure sensor 24 is provided between the three-way catalyst 22 and the exhaust throttle valve 23. The exhaust pressure sensor 24 detects the exhaust pressure of the exhaust pipe, and outputs the detected exhaust pressure to the ECU 1A.

  FIG. 10 is a flowchart illustrating an example of the boosting process according to the second embodiment. Note that the processes in steps S21 and S22 shown in FIG. 10 are the same as the processes in steps S1 and S2 shown in FIG.

  In FIG. 10, in the process of step S <b> 23, the CPU determines the valve opening degree of the exhaust throttle valve 63 with reference to the control map related to the exhaust throttle. The control map related to the exhaust throttle is indicated by the relationship between the operating state (for example, the exhaust pressure) and the valve opening of the exhaust throttle valve 63. The control map has a relationship in which the valve opening decreases as the exhaust pressure decreases, that is, the valve closes.

  Therefore, when the exhaust pressure sensor 24 detects the exhaust pressure, and the ECU 1A determines that the detected exhaust pressure has decreased compared to the state before the opening / closing valve 43 is opened, the exhaust throttle valve 63 is It will be closed. In this case, the valve opening degree of the exhaust throttle valve 63 may be completely closed or may be partially closed. By controlling the exhaust throttle 63 as described above, a decrease in exhaust pressure is suppressed. For this reason, the fall of supercharging pressure is suppressed and also the fall of in-cylinder pressure is suppressed. Therefore, combustion deterioration can be suppressed.

  The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to such specific embodiments, and various modifications can be made within the scope of the gist of the present invention described in the claims.・ Change is possible.

1A ECU
DESCRIPTION OF SYMBOLS 10 Intake system 20 Exhaust system 22 Three-way catalyst 23 Exhaust throttle valve 24 Exhaust pressure sensor 30 Fuel injection system 40 Turbo supercharger 42 Turbine 43 On-off valve 43a Bypass passage 50 Internal combustion engine main body 63 In-cylinder pressure sensor

Claims (10)

An internal combustion engine body;
A turbocharger provided with a turbine on the exhaust pipe side connected to the internal combustion engine body;
A catalyst disposed downstream of the turbine;
A bypass passage for bypassing the turbine and allowing exhaust to flow directly into the catalyst;
Opening and closing means for opening and closing the bypass passage;
A pressure-increasing means for increasing an in-cylinder pressure when the bypass passage is opened by the opening / closing means and the exhaust gas directly flows into the catalyst;
An internal combustion engine.   The boosting means increases the in-cylinder pressure when an in-cylinder pressure when the bypass passage is opened by the opening / closing means is lower than an in-cylinder pressure when the bypass passage is closed by the opening / closing means. The internal combustion engine according to claim 1. Storage means for storing an exhaust deterioration region caused by an operating state of the internal combustion engine body when the bypass passage is opened by the opening / closing means;
3. The internal combustion engine according to claim 1, wherein the booster increases the in-cylinder pressure when an operating state is included in the predetermined deterioration region.   The said pressure | voltage rise means raises the said in-cylinder pressure by controlling in the direction which closes the variable nozzle provided in the said variable nozzle turbo, when the said turbo supercharger is a variable nozzle turbo. Item 4. The internal combustion engine according to any one of Items 1 to 3.   The boosting means increases the in-cylinder pressure by increasing the supercharging pressure by increasing the rotational speed of an electric motor provided in the electric assist turbo when the turbocharger is an electric assist turbo. The internal combustion engine according to any one of claims 1 to 3, wherein   6. The internal combustion engine according to claim 4, wherein the boosting unit changes an ignition condition of an ignition device when the internal combustion engine main body is a gasoline engine.   The internal combustion engine according to claim 4 or 5, wherein the boosting means changes an injection condition of a fuel injection device when the internal combustion engine body is a diesel engine.   8. The cylinder pressure according to claim 1, wherein the boosting means increases the in-cylinder pressure by changing a phase and / or a working angle of the intake valve toward a side where the intake air amount increases. The internal combustion engine described in 1.   The said pressure | voltage rise means raises a cylinder pressure by changing the phase of an exhaust valve and / or a working angle to the side where exhaust pressure increases, The any one of Claim 1 to 8 characterized by the above-mentioned. Internal combustion engine. The internal combustion engine according to any one of claims 1 to 9, wherein the pressure increasing means increases the in-cylinder pressure by controlling an exhaust throttle valve provided downstream of the catalyst to a closing side. organ.

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