JP2008002348A - Exhaust gas recirculation device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology for reducing exhaust gas emission when fuel supply is restarted from a fuel supply stop state, in an exhaust gas recirculation device for an internal combustion engine. <P>SOLUTION: The exhaust gas recirculation device for an internal combustion engine comprises: a turbocharger having a turbine disposed to an exhaust passage and a compressor disposed to an intake passage; a low-pressure EGR passage; and a high-pressure EGR passage; a time measurement means S103 measuring a fuel supply stop time in a fuel supply stop state where fuel supply to the internal combustion engine is stopped; and high-pressure EGR gas amount control means S105, S106 each correcting to increase a high-pressure EGR gas amount of the high-pressure EGR passage according to the fuel supply stop time in the fuel supply stop state measured by the time measurement means after the restart of the fuel supply from the fuel supply stop state. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an exhaust gas recirculation device for an internal combustion engine.

A low-pressure EGR passage that takes in part of the exhaust gas from an exhaust passage downstream of the turbine as low-pressure exhaust gas recirculation (hereinafter referred to as EGR) gas and recirculates the low-pressure EGR gas to an intake passage upstream of the compressor, and an exhaust gas upstream of the turbine A high-pressure EGR passage that takes in a part of the exhaust gas from the passage as high-pressure EGR gas and recirculates the high-pressure EGR gas to the intake passage downstream of the compressor, performs EGR using the high-pressure EGR passage at low loads, and at high loads A technique for performing EGR using a low-pressure EGR passage is known (see, for example, Patent Document 1).
Japanese Patent Laying-Open No. 2005-076456 JP 2004-027956 A

  By the way, in a fuel supply stop state (hereinafter referred to as fuel cut-off) in which fuel supply to the cylinder of the internal combustion engine is stopped when the internal combustion engine is decelerated, the first throttle is closed and the low pressure EGR passage and the high pressure EGR passage are used. Circulate the gas flowing through the internal combustion engine. At this time, even if the first throttle is closed, the intake air may leak into the intake passage downstream of the first throttle. Then, the intake air that leaks into the intake passage downstream of the first throttle causes a time change that gradually increases the oxygen concentration of the circulating gas.

  For this reason, when the fuel supply into the cylinder of the internal combustion engine is resumed from the fuel cut-off state, it circulates in the internal combustion engine due to an increase in the oxygen concentration of the gas that was circulating in the fuel cut-off state. The EGR ratio of the gas to be reduced is reduced, and there is a concern that the exhaust emission may increase due to an increase in the combustion temperature in the cylinder of the internal combustion engine and NOx being discharged from the internal combustion engine.

  On the other hand, the low pressure EGR passage has a long path length, and it takes time for the low pressure EGR gas to flow through the low pressure EGR passage. Therefore, an arrival delay (hereinafter referred to as a low-pressure EGR gas recirculation delay) occurs until a part of the exhaust gas in the exhaust gas passage is actually recirculated as low-pressure EGR gas to the internal combustion engine via the low-pressure EGR passage.

  Therefore, when the fuel supply into the cylinder of the internal combustion engine is resumed from the fuel cut-off state, an attempt is made to increase the amount of EGR gas flowing through the internal combustion engine by supplying the low pressure EGR gas using the low pressure EGR passage. However, it is difficult to ensure the amount of EGR gas immediately after resumption of fuel supply due to the delay in reflux of the low-pressure EGR gas.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a technique for reducing exhaust emission when fuel supply is resumed from a fuel supply stop state in an exhaust gas recirculation device for an internal combustion engine. There is to do.

In the present invention, the following configuration is adopted. That is,
A turbocharger having a turbine disposed in an exhaust passage of the internal combustion engine and a compressor disposed in an intake passage of the internal combustion engine;
A low pressure EGR passage that takes a part of the exhaust gas as a low pressure EGR gas from the exhaust passage downstream of the turbine and recirculates the low pressure EGR gas to an intake passage upstream of the compressor;
A high-pressure EGR passage that takes a part of exhaust gas as a high-pressure EGR gas from an exhaust passage upstream of the turbine and recirculates the high-pressure EGR gas to an intake passage downstream of the compressor;
Timing means for timing the fuel supply stop time in the fuel supply stop state for stopping the fuel supply to the internal combustion engine;
After restarting fuel supply from the fuel supply stop state, the high pressure EGR gas amount for correcting the increase in the high pressure EGR gas amount in the high pressure EGR passage according to the fuel supply stop time in the fuel supply stop state measured by the time measuring means Control means;
An exhaust gas recirculation device for an internal combustion engine.

  In the present invention, after the fuel supply is resumed from the fuel cut-off state, the amount of high-pressure EGR gas in the high-pressure EGR passage is corrected to be increased according to the fuel supply stop time in the fuel cut-off state.

  Here, the high pressure EGR passage has a short path length, and it does not take time for the high pressure EGR gas to flow through the high pressure EGR passage. Therefore, the responsiveness until a part of the exhaust gas in the exhaust passage is actually returned to the internal combustion engine through the high-pressure EGR passage as high-pressure EGR gas is fast. Therefore, the high-pressure EGR gas can flow into the internal combustion engine immediately after the fuel supply is resumed from the fuel cut-off state.

  According to the present invention, the corrected high-pressure EGR gas flows into the internal combustion engine immediately after resumption of fuel supply, increases the EGR ratio of the gas flowing through the internal combustion engine, and increases the combustion temperature in the cylinder of the internal combustion engine. It is possible to suppress the emission of NOx from the internal combustion engine, and to reduce the exhaust emission when the fuel supply is resumed from the fuel cutoff state.

  The high-pressure EGR gas amount control means may increase the high-pressure EGR gas amount in the high-pressure EGR passage to be increased and corrected as the fuel supply stop time becomes longer at least in a predetermined range of the fuel supply stop time.

  According to the present invention, by increasing the amount of high-pressure EGR gas that is corrected to increase as the fuel supply stop time becomes longer, the EGR ratio of the gas flowing through the internal combustion engine that has decreased as the fuel supply stop time becomes longer is determined. The increase in the combustion temperature in the cylinder can be increased to a rate that can be suppressed.

  The high pressure EGR gas amount control means may stop the increase correction at a timing when the low pressure EGR gas amount recirculated to the internal combustion engine after resuming fuel supply from the fuel supply stop state becomes a predetermined amount.

  According to this, the EGR ratio of the gas flowing through the internal combustion engine after resuming the fuel supply can be stabilized in consideration of the low-pressure EGR gas amount after the fuel supply is resumed from the fuel cut-off state.

  Here, the predetermined amount is a low-pressure EGR gas amount that can sufficiently suppress an increase in combustion temperature when the amount of low-pressure EGR gas recirculated into the cylinder of the internal combustion engine reaches the amount.

  According to the present invention, in an exhaust gas recirculation device for an internal combustion engine, exhaust emission when fuel supply is resumed from a fuel supply stop state can be reduced.

  Specific examples of the present invention will be described below.

<Example 1>
FIG. 1 is a diagram showing a schematic configuration of an internal combustion engine to which the exhaust gas recirculation apparatus for an internal combustion engine according to this embodiment is applied and its intake / exhaust system.

  An internal combustion engine 1 shown in FIG. 1 is a water-cooled four-cycle diesel engine having four cylinders 2.

  An intake passage 3 is connected to the internal combustion engine 1. A compressor housing 5 a of a turbocharger 5 that operates using exhaust energy as a drive source is disposed in the intake passage 3. A first throttle 6 for adjusting the flow rate of intake air flowing through the intake passage 3 is disposed in the intake passage 3 upstream of the compressor housing 5a. The first throttle 6 is opened and closed by an electric actuator. An air flow meter 7 that outputs a signal corresponding to the flow rate of the intake air flowing through the intake passage 3 is disposed in the intake passage 3 upstream of the first throttle 6. The air flow meter 7 measures the intake air amount of the internal combustion engine 1.

  An intercooler 8 that performs heat exchange between the intake air and the outside air is disposed in the intake passage 3 downstream of the compressor housing 5a. A second throttle 9 for adjusting the flow rate of the intake air flowing through the intake passage 3 is disposed in the intake passage 3 downstream of the intercooler 8. The second throttle 9 is opened and closed by an electric actuator.

  On the other hand, an exhaust passage 4 is connected to the internal combustion engine 1. In the middle of the exhaust passage 4, a turbine housing 5b of the turbocharger 5 is disposed. A particulate filter (hereinafter simply referred to as a filter) 10 is disposed in the exhaust passage 4 downstream of the turbine housing 5b. The filter 10 carries an NOx storage reduction catalyst (hereinafter simply referred to as NOx catalyst). The filter 10 collects particulate matter in the exhaust gas. Further, the NOx catalyst occludes nitrogen oxide (NOx) in the exhaust gas when the oxygen concentration of the exhaust gas flowing into the NOx catalyst is high, and on the other hand, when the oxygen concentration of the exhaust gas flowing into the NOx catalyst decreases. Releases the stored NOx. At that time, if a reducing component such as hydrocarbon (HC) or carbon monoxide (CO) is present in the exhaust, NOx released from the NOx catalyst is reduced. Note that an oxidation catalyst or a three-way catalyst may be supported on the filter 10 instead of the NOx catalyst.

  The internal combustion engine 1 is provided with a low pressure EGR device 30 that recirculates (recirculates) part of the exhaust gas flowing through the exhaust passage 4 to the intake passage 3 at a low pressure. The low pressure EGR device 30 includes a low pressure EGR passage 31, a low pressure EGR valve 32, and an EGR cooler 33.

  The low pressure EGR passage 31 connects the exhaust passage 4 downstream of the filter 10 and the intake passage 3 upstream of the compressor housing 5 a and downstream of the first throttle 6. Through this low-pressure EGR passage 31, the exhaust gas is recirculated to the internal combustion engine at a low pressure. In this embodiment, the exhaust gas recirculated through the low pressure EGR passage 31 is referred to as low pressure EGR gas.

  Further, the low pressure EGR valve 32 adjusts the amount of the low pressure EGR gas flowing through the low pressure EGR passage 31 by adjusting the passage sectional area of the low pressure EGR passage 31. Further, the EGR cooler 33 exchanges heat between the low-pressure EGR gas passing through the EGR cooler 33 and the cooling water of the internal combustion engine 1 to lower the temperature of the low-pressure EGR gas.

  The internal combustion engine 1 is provided with a high-pressure EGR device 40 that recirculates a part of the exhaust gas flowing through the exhaust passage 4 to the intake passage 3 at a high pressure. The high pressure EGR device 40 includes a high pressure EGR passage 41 and a high pressure EGR valve 42.

  The high pressure EGR passage 41 connects the exhaust passage 4 upstream of the turbine housing 5 b and the intake passage 3 downstream of the second throttle 9. Through this high-pressure EGR passage 41, the exhaust gas is recirculated to the internal combustion engine at a high pressure. In this embodiment, the exhaust gas recirculated through the high pressure EGR passage 41 is referred to as high pressure EGR gas.

  Further, the high pressure EGR valve 42 adjusts the amount of high pressure EGR gas flowing through the high pressure EGR passage 41 by adjusting the passage sectional area of the high pressure EGR passage 41.

  The internal combustion engine 1 configured as described above is provided with an ECU 11 that is an electronic control unit for controlling the internal combustion engine 1. The ECU 11 is a unit that controls the operation state of the internal combustion engine 1 in accordance with the operation conditions of the internal combustion engine 1 and the request of the driver.

  Further, the ECU 11 outputs an electrical signal corresponding to the amount of depression of the accelerator pedal 12 by the driver, and an accelerator opening sensor 13 that can detect the engine load and a crank position sensor 14 that detects the engine speed are electrically wired. The output signals of these various sensors are input to the ECU 11.

  On the other hand, the ECU 11 is connected to the first throttle 6, the second throttle 9, the low pressure EGR valve 32, and the high pressure EGR valve 42 through electric wiring, and these devices are controlled by the ECU 11.

  The amount of low-pressure EGR gas recirculated to the internal combustion engine 1 is adjusted by at least one of the low-pressure EGR valve 32 or the first throttle 6. Further, the amount of high pressure EGR gas recirculated to the internal combustion engine 1 is adjusted by at least one of the high pressure EGR valve 42 and the second throttle 9.

  By the way, when the internal combustion engine 1 is decelerated (during engine braking) or the like, the first throttle 6 is closed, the second throttle 9, the low pressure EGR valve 32, and the high pressure EGR valve 42 are opened. A gas flowing through the internal combustion engine 1 is circulated using an intake passage 3, an exhaust passage 4, a low pressure EGR passage 31, and a high pressure EGR passage 41 downstream of the throttle 6.

  When the gas is circulated in this way, the intake air may leak into the intake passage 3 downstream of the first throttle 6 even if the first throttle 6 is closed. The intake air that leaks into the intake passage 3 downstream from the first throttle 6 causes a time change that gradually increases the oxygen concentration of the circulating gas. That is, as the elapsed time (fuel supply stop time) in the fuel cut-off state becomes longer, the oxygen concentration of the circulating gas increases.

  For this reason, when the fuel supply into the cylinder 2 of the internal combustion engine 1 is resumed from the fuel cut-off state, the internal combustion engine 1 is caused by an increase in the oxygen concentration of the circulating gas in the fuel cut-off state. The EGR ratio of the gas flowing in the engine has decreased, and when combustion in the cylinder 2 of the internal combustion engine 1 is resumed as it is, the combustion temperature in the cylinder 2 of the internal combustion engine 1 rises and NOx is discharged from the internal combustion engine 1. There is a possibility that the exhaust emission will be increased.

  On the other hand, the low pressure EGR passage 31 has a long path length, and it takes time for the low pressure EGR gas to flow through the low pressure EGR passage 31. For this reason, the low-pressure EGR gas recirculation delay occurs.

  Therefore, when the fuel supply into the cylinder 2 of the internal combustion engine 1 is resumed from the fuel cutoff state, the amount of EGR gas flowing through the internal combustion engine 1 is reduced by supplying the low pressure EGR gas using the low pressure EGR passage 31. Even if an attempt is made to increase the EGR ratio of the gas flowing through the internal combustion engine 1, the low-pressure EGR gas amount does not increase immediately after resumption of fuel supply due to the recirculation delay of the low-pressure EGR gas. Securing is difficult.

  Therefore, in this embodiment, after the fuel supply is resumed from the fuel cut-off state, the amount of high-pressure EGR gas in the high-pressure EGR passage 41 is corrected to increase in accordance with the fuel supply stop time in the fuel cut-off state.

  Specifically, after the fuel supply is resumed from the fuel cut-off state, the higher the EGR gas amount as the fuel supply stop time becomes longer in order to return the reduced EGR ratio to the predetermined EGR ratio before the fuel cut-off state. The high pressure EGR valve 42 is moved to the open side so as to increase the amount by the amount of increase correction.

  Here, the high pressure EGR passage 41 has a short path length, and it does not take time for the high pressure EGR gas to flow through the high pressure EGR passage 41. Therefore, the responsiveness until a part of the exhaust gas in the exhaust passage 4 is actually recirculated to the internal combustion engine 1 through the high pressure EGR passage 41 as the high pressure EGR gas is fast. Therefore, the high-pressure EGR gas can flow into the internal combustion engine 1 immediately after the fuel supply is resumed from the fuel cut-off state.

  For this reason, the high-pressure EGR gas corrected for the increase flows into the internal combustion engine 1 immediately after resumption of fuel supply, and the increase in the combustion temperature in the cylinder 2 of the internal combustion engine 1 is suppressed by controlling the EGR ratio of the gas flowing through the internal combustion engine 1. When the fuel supply is resumed from the fuel cut-off state by increasing it to a possible ratio, suppressing an increase in the combustion temperature in the cylinder 2 of the internal combustion engine 1 to suppress the discharge of NOx from the internal combustion engine 1 Exhaust emissions can be reduced.

  Further, in this embodiment, the timing at which the low-pressure EGR gas recirculation delay after the fuel supply is resumed from the fuel cut-off state, that is, the amount of low-pressure EGR gas recirculated to the internal combustion engine 1 before the fuel cut-off state is reached. At the timing of returning to the predetermined amount, the increase correction is stopped, that is, the increase correction portion of the high pressure EGR gas amount is set to zero.

  Specifically, in order to maintain a predetermined EGR ratio even when low pressure EGR gas is mixed, the increase correction amount of the high pressure EGR gas amount is decreased according to the degree of the flow of the low pressure EGR gas recirculated to the internal combustion engine 1. As described above, the high pressure EGR valve 42 is gradually moved to the closing side.

  According to this, considering the amount of low-pressure EGR gas after restarting fuel supply from the fuel cutoff state, the EGR ratio of the gas flowing through the internal combustion engine 1 after restarting fuel supply from the fuel cutoff state is stabilized. Can be made.

  Next, the flow of EGR gas supply control accompanying the fuel cutoff according to this embodiment will be described. FIG. 2 is a flowchart showing a flow of EGR gas supply control accompanying fuel cut-off according to the present embodiment. This routine is repeatedly executed every predetermined time.

In step S101, the ECU 11 determines whether or not to shift the internal combustion engine 1 to the fuel cutoff state. Whether or not to shift to the fuel cut-off state is determined based on the engine load detected by the accelerator opening sensor 13, the engine speed detected by the crank position sensor 14, the intake air amount detected by the air flow meter 7, and the like. This is determined by turning off.

  If it is determined in step S101 that the fuel cut-off state is not entered, the ECU 11 once ends this routine. If it is determined that the fuel cut-off state is to be entered, the process proceeds to step S102.

  In step S102, the ECU 11 closes the first throttle 6 and opens the second throttle 9, the low-pressure EGR valve 32, and the high-pressure EGR valve 42 in accordance with the execution of the fuel cutoff that is controlled separately from this routine. Thus, the gas flowing through the internal combustion engine 1 is circulated using the intake passage 3, the exhaust passage 4, the low pressure EGR passage 31, and the high pressure EGR passage 41 downstream of the first throttle 6 of the internal combustion engine 1.

  In step S103 following step S102, the ECU 11 measures the elapsed time of the fuel cutoff state, that is, the fuel supply stop time. The ECU 11 performs measurement of the fuel supply stop time. The ECU 11 that executes this step corresponds to the time measuring means of the present invention.

  In step S104 subsequent to step S103, the ECU 11 determines whether or not to restart the fuel supply from the fuel cutoff state into the cylinder 2 of the internal combustion engine 1. Whether or not to restart the fuel supply depends on the engine load detected by the accelerator opening sensor 13, the engine speed detected by the crank position sensor 14, the intake air amount detected by the air flow meter 7, and the like. It is judged by doing.

  If it is determined in step S104 that the fuel supply is not resumed, the ECU 11 returns to step S103 and continues to measure the fuel supply stop time. If it is determined that the fuel supply is resumed, the process proceeds to step S105.

  In step S105, the ECU 11 obtains a correction amount for correcting the opening degree of the high pressure EGR valve 42 in order to increase and correct the high pressure EGR gas after the fuel supply is resumed from the fuel cutoff state. This correction amount is a value indicating how much the opening degree of the high pressure EGR valve 42 is actually changed from the opening degree of the reference value. The correction amount is obtained according to the fuel supply stop time measured in step S103 using FIG. 3 described later.

  Here, FIG. 3 is a diagram showing the relationship between the fuel supply stop time and the correction amount in the fuel cutoff state measured in step S103. That is, as the fuel supply stop time becomes longer, the correction amount increases more and the opening degree of the high pressure EGR valve 32 becomes larger. On the map shown in FIG. 3, when the fuel supply stop time becomes too long, the correction value is limited and the maximum value is set. The reason why the maximum value is set for the correction amount in this way is to prevent the correction amount from becoming too large and the amount of high-pressure EGR gas to be increased and corrected from being excessively large, thereby causing adverse effects such as misfire of the internal combustion engine 1. is there. The relationship of FIG. 3 is obtained in advance through experiments or the like and mapped, and stored in the ECU 11.

  In step S106 following step S105, the ECU 11 adjusts the opening degree of the high pressure EGR valve 42 so that the opening degree of the high pressure EGR valve 42 becomes a target value.

  The initial target value of the opening of the high pressure EGR valve 42 at the start of this step is a value obtained by adding the correction amount obtained in step S105 to the reference value of the opening of the high pressure EGR valve 32 opened in step S102.

When the control in this step is executed and time elapses, the low-pressure EGR gas flows back into the internal combustion engine 1 and flows in regardless of the low-pressure EGR gas recirculation delay. The correction amount is decreased to decrease the increase correction amount of the high-pressure EGR gas amount so that the predetermined EGR ratio is maintained even if the low-pressure EGR gas is mixed according to the degree of the flow of the low-pressure EGR gas accompanied by the reflux delay. There is a need. Therefore, the correction amount after the start of control is made smaller than the correction amount obtained using FIG. For this reason, the target value of the opening degree of the high pressure EGR valve 42 becomes smaller than the initial target value. The correction amount is decreased according to the elapsed time after the fuel supply is restarted from the fuel cut-off state using FIG. 4 described later.

  Here, FIG. 4 is a diagram showing the relationship between the elapsed time after resumption of fuel supply and the correction amount. That is, as the elapsed time after the resumption of fuel supply becomes longer and the inflow of the low pressure EGR gas increases, the correction amount is decreased and the opening degree of the high pressure EGR valve 42 is gradually reduced. Then, at the timing when the low-pressure EGR gas recirculation delay disappears, that is, when the low-pressure EGR gas amount returns to the predetermined amount before the fuel cut-off state is reached, the correction amount is set to 0 and the increase correction is stopped, and the high-pressure EGR valve 42 is stopped. Is returned to the reference value. The relationship shown in FIG. 4 is obtained in advance through experiments and is mapped and stored in the ECU 11.

  In this way, by controlling the opening degree of the high pressure EGR valve 42 after the fuel supply is restarted from the fuel cut-off state, the EGR ratio of the gas flowing through the internal combustion engine 1 is increased. An increase in the combustion temperature in the cylinder 2 can be suppressed to suppress NOx from being discharged from the internal combustion engine 1, and exhaust emission when fuel supply is resumed from the fuel cut-off state can be reduced.

  In this embodiment, the ECU 11 that executes the processes of steps S105 and S106 corresponds to the high-pressure EGR gas amount control means in the present invention.

  In the flowchart of this embodiment shown in FIG. 2, the opening degree of the high pressure EGR valve 42 is corrected in order to correct the increase in the high pressure EGR gas amount. The opening degree of 9 may be corrected. In this case, since the differential pressure between the exhaust passage 4 side and the intake passage 3 side of the high pressure EGR passage 41 is increased by moving the second throttle 9 to the closed side, the amount of high pressure EGR gas can be increased.

  The exhaust gas recirculation apparatus for an internal combustion engine according to the present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the gist of the present invention.

1 is a diagram illustrating an internal combustion engine and an intake / exhaust system thereof according to Embodiment 1. FIG. 3 is a flowchart showing a flow of EGR gas supply control accompanying fuel cut-off according to the first embodiment. It is the figure which showed the relationship between the fuel supply stop time in the fuel cutoff state which concerns on Example 1, and a correction amount. It is the figure which showed the relationship between the elapsed time after the fuel supply resumption which concerns on Example 1, and a correction amount.

Explanation of symbols

1 Internal combustion engine 2 Cylinder 3 Intake passage 4 Exhaust passage 5 Turbocharger 5a Compressor housing 5b Turbine housing 6 First throttle 7 Air flow meter 8 Intercooler 9 Second throttle 10 Filter 12 Accelerator pedal 13 Accelerator opening sensor 14 Crank position sensor 30 Low pressure EGR device 31 Low pressure EGR passage 32 Low pressure EGR valve 33 EGR cooler 40 High pressure EGR device 41 High pressure EGR passage 42 High pressure EGR valve

Claims (3)

A turbocharger having a turbine disposed in an exhaust passage of the internal combustion engine and a compressor disposed in an intake passage of the internal combustion engine;
A low pressure EGR passage that takes a part of the exhaust gas as a low pressure EGR gas from the exhaust passage downstream of the turbine and recirculates the low pressure EGR gas to an intake passage upstream of the compressor;
A high-pressure EGR passage that takes a part of exhaust gas as a high-pressure EGR gas from an exhaust passage upstream of the turbine and recirculates the high-pressure EGR gas to an intake passage downstream of the compressor;
Timing means for timing the fuel supply stop time in the fuel supply stop state for stopping the fuel supply to the internal combustion engine;
After restarting fuel supply from the fuel supply stop state, the high pressure EGR gas amount for correcting the increase in the high pressure EGR gas amount in the high pressure EGR passage according to the fuel supply stop time in the fuel supply stop state measured by the time measuring means Control means;
An exhaust gas recirculation device for an internal combustion engine, comprising:   The high-pressure EGR gas amount control means increases the high-pressure EGR gas amount in the high-pressure EGR passage to be increased and corrected as the fuel supply stop time becomes longer at least in a predetermined range of the fuel supply stop time. The exhaust gas recirculation device for an internal combustion engine according to claim 1.   The high-pressure EGR gas amount control means stops the increase correction at a timing when the low-pressure EGR gas amount recirculated to the internal combustion engine after restarting fuel supply from the fuel supply stop state becomes a predetermined amount. The exhaust gas recirculation device for an internal combustion engine according to claim 1 or 2.

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