JP2010185423A - Exhaust emission purifying apparatus for internal-combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exhaust emission purifying apparatus for an internal-combustion engine capable of performing more suitably regeneration of an exhaust emission purifying member provided in an exhaust passage. <P>SOLUTION: A DPF 26 for collecting soot in exhaust emissions is provided in an exhaust passage 14 of an internal combustion engine 10. When a deposition amount of soot at the DPF 26 exceeds a predetermined amount, fuel addition to the DPF 26 is performed. When an addition amount is set at the time of the fuel addition, an electronic control device 50 calculates a correction amount with respect to a basic addition amount. As the correction amount, a correction amount based on deposition amount of soot and an intake air temperature and a correction amount based on the deposition amount of soot and atmospheric pressure are calculated. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an exhaust purification device for an internal combustion engine that adds fuel to an exhaust purification member provided in an exhaust passage.

  In recent years, exhaust purification members that collect and purify particulate matter in exhaust gas using a filter provided in an exhaust passage have been adopted in internal combustion engines such as in-vehicle diesel engines. In such an exhaust purification member, it is necessary to regenerate the filter by removing the deposited SOOT before the filter is clogged due to the accumulation of collected SOOT (soot).

  Conventionally, the thing of patent document 1 is known as an exhaust gas purification device which performs regeneration of such a filter. In this exhaust purification device, fuel is added to the exhaust flowing into the filter. The SOOT collected by the filter by this fuel addition is oxidized (including combustion), and the filter is regenerated. Moreover, in the thing of this patent document 1, the addition amount of a fuel is correct | amended according to the accumulation amount of SOOT in a filter.

JP 2001-193440 A

  By the way, the oxidation state of the particulate matter in the exhaust purification member also changes depending on the intake air temperature and the atmospheric pressure state. However, such a point is not considered in the conventional apparatus. For this reason, in some cases, deterioration of fuel consumption due to an increase in regeneration time, excessive temperature rise of the exhaust purification member due to excessive oxidation of particulate matter, or excess of added fuel, etc. There is a concern that inconveniences such as passing through and being discharged as white smoke may occur. Therefore, there is room for further improvement in that the exhaust purification member is more appropriately regenerated.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide an exhaust purification device for an internal combustion engine that can more suitably regenerate the exhaust purification member provided in the exhaust passage.

In the following, means for achieving the above object and its effects are described.
The invention according to claim 1 includes an exhaust purification member that is provided in an exhaust passage of the internal combustion engine and collects particulate matter in the exhaust, and the amount of particulate matter deposited on the exhaust purification member is a predetermined amount. In the exhaust gas purification apparatus for an internal combustion engine that adds fuel to the exhaust purification member when it exceeds, and calculates a correction amount for the basic addition amount when setting the addition amount at the time of fuel addition, the accumulation amount and intake air temperature are used as the correction amount. The gist is to calculate at least one of the correction amount based on the above and the correction amount based on the accumulation amount and the atmospheric pressure.

  In this configuration, the correction amount for the basic addition amount is calculated when fuel addition to the exhaust purification member is performed. Here, in the same configuration, such a correction amount is calculated not only by the amount of particulate matter accumulated but also by taking into account the intake air temperature and atmospheric pressure that affect the oxidation state of the particulate matter in the exhaust purification member. Yes. Therefore, regeneration of the exhaust purification member can be performed more suitably.

BRIEF DESCRIPTION OF THE DRAWINGS Schematic which shows the internal combustion engine to which this is applied, and its periphery structure about one Embodiment of the exhaust gas purification device of the internal combustion engine concerning this invention. 6 is a flowchart showing the procedure of a reproduction flag setting process in the embodiment. The flowchart which shows the procedure of the addition amount calculation process in the embodiment. The conceptual diagram which shows the setting aspect of a 1st correction coefficient. The conceptual diagram which shows the setting aspect of a 2nd correction coefficient. The conceptual diagram which shows the setting aspect of a 3rd correction coefficient.

Hereinafter, an embodiment of an exhaust gas purification apparatus for an internal combustion engine according to the present invention will be described with reference to FIGS.
FIG. 1 shows a configuration of an internal combustion engine 10 to which the present embodiment is applied. The internal combustion engine 10 is a diesel engine that includes a common rail fuel injection device and a turbocharger 11, and mainly includes an intake passage 12, a combustion chamber 13, an exhaust passage 14, and the like.

  In the intake passage 12 constituting the intake system of the internal combustion engine 10, an air flow meter 16, a compressor 17 of the turbocharger 11, an intercooler 18, And an intake throttle valve 19 is provided. The intake passage 12 is branched at an intake manifold 20 provided on the downstream side of the intake throttle valve 19 and connected to the combustion chamber 13 of each cylinder of the internal combustion engine 10 via an intake port 21.

  On the other hand, in the exhaust passage 14 constituting the exhaust system of the internal combustion engine 10, an exhaust port 22 is connected to the combustion chamber 13 of each cylinder. The exhaust port 22 is connected to the turbocharger 11 via the exhaust manifold 23. Connected to the exhaust turbine 24. In addition, a NOx catalytic converter 25, a DPF 26, and an oxidation catalytic converter 27 are arranged downstream from the exhaust turbine 24 in the exhaust passage 14 in order from the upstream side.

  The NOx catalytic converter 25 carries an NOx storage reduction catalyst. The NOx catalyst stores NOx in the exhaust when the oxygen concentration of the exhaust is high, and releases the stored NOx when the oxygen concentration of the exhaust is low. Further, the NOx catalyst reduces and purifies the released NOx if there is sufficient unburned fuel component as a reducing agent at the time of releasing the NOx.

The DPF 26 is a filter formed of a porous material, and SOOT in the exhaust gas is collected in the filter. The DPF 26 constitutes the exhaust purification member.
The oxidation catalyst converter 27 carries an oxidation catalyst, and HC and CO in the exhaust are oxidized and purified.

  Note that, on the upstream side and the downstream side of the DPF 26 in the exhaust passage 14, there are a first exhaust temperature sensor 28 that detects the first exhaust temperature EXt1 that is the temperature of the exhaust gas flowing into the DPF 26, and the exhaust gas temperature after passing through the DPF 26. A second exhaust temperature sensor 29 for detecting the second exhaust temperature EXt2 is provided. In addition, a differential pressure sensor 30 that detects a pressure difference ΔP between the exhaust upstream side and the exhaust downstream side of the DPF 26 is disposed in the exhaust passage 14. Further, oxygen sensors 32 for detecting the oxygen concentration in the exhaust gas are disposed between the DPF 26 and the oxidation catalytic converter 27, respectively.

  Further, the internal combustion engine 10 is provided with an exhaust gas recirculation (hereinafter referred to as EGR) device that recirculates a part of the exhaust gas to the air in the intake passage 12. The EGR device includes an EGR passage 33 that allows the exhaust passage 14 and the intake passage 12 to communicate with each other. The most upstream portion of the EGR passage 33 is connected to the exhaust upstream side of the exhaust turbine 24 in the exhaust passage 14. The EGR passage 33 is provided with an EGR catalyst 34 for reforming the recirculated exhaust, an EGR cooler 35 for cooling the exhaust, and an EGR valve 36 for adjusting the flow rate of the exhaust from the upstream side. The most downstream portion of the EGR passage 33 is connected to the downstream side of the intake throttle valve 19 in the intake passage 12.

  On the other hand, a fuel injection valve 40 that injects fuel to be used for combustion in the combustion chamber 13 is disposed in the combustion chamber 13 of each cylinder of the internal combustion engine 10. The fuel injection valve 40 of each cylinder is connected to a common rail 42 via a high pressure fuel supply pipe 41. High pressure fuel is supplied to the common rail 42 through a fuel pump 43. The pressure of the high-pressure fuel in the common rail 42 is detected by a rail pressure sensor 44 attached to the common rail 42.

  Further, low pressure fuel is supplied from the fuel pump 43 to the addition valve 46 through the low pressure fuel supply pipe 45. The addition valve 46 is disposed in the exhaust port 22 of a specific cylinder, injects fuel toward the exhaust turbine 24 side, and adds the fuel into the exhaust.

  The electronic control unit 50 that controls various controls of the internal combustion engine 10 includes a CPU that executes various calculation processes related to the control of the internal combustion engine 10, a ROM that stores programs and data necessary for the control, a calculation result of the CPU, and the like. A RAM that is temporarily stored, an input / output port for inputting / outputting signals to / from the outside, and the like are provided. In addition to the above-described sensors, the input port of the electronic control unit 50 detects the engine rotational speed sensor 51 that detects the engine rotational speed NE, the accelerator sensor 52 that detects the accelerator operation amount, and the opening degree of the intake throttle valve 19. A throttle valve sensor 53 and the like are connected. Also connected to this input port are an intake air temperature sensor 54 that detects the intake air temperature INT, a water temperature sensor 55 that detects the cooling water temperature THW of the internal combustion engine 10, and an atmospheric pressure sensor 56 that detects the atmospheric pressure AP. The output ports of the electronic control unit 50 are connected to drive circuits such as the intake throttle valve 19, the fuel injection valve 40, the fuel pump 43, the addition valve 46, and the EGR valve 36.

  The electronic control unit 50 outputs a command signal to the drive circuit of each device connected to the output port according to the engine operating state grasped from the detection signal input from each sensor. Thus, the electronic control unit 50 performs various controls such as control of the fuel injection timing and fuel injection amount by the fuel injection valve 40, opening control of the intake throttle valve 19, and EGR control based on the opening control of the EGR valve 36. Has been.

  Further, the electronic control unit 50 performs fuel addition to the exhaust gas by the addition valve 46 as part of such control. The addition of fuel to the exhaust gas by the addition valve 46 is performed in the following controls, that is, regeneration control of the DPF 26, NOx reduction control, and S poisoning recovery control.

  The regeneration control is performed to eliminate clogging of the DPF 26 by burning the SOOT collected by the DPF 26 and discharging it as carbon dioxide and water. During this regeneration control, regeneration processing for adding fuel to the exhaust from the addition valve 46 is executed, whereby the DPF 26 is heated to a high temperature (for example, 600 to 700 ° C.), and the collected SOOT is oxidized and burned. Is planned. During the regeneration process, the addition amount T is calculated in an addition amount calculation process described later, and injection control of the addition valve 46 is performed so that the addition amount T is obtained.

  The NOx reduction control is performed to reduce and release NOx stored in the NOx catalyst of the NOx catalytic converter 25 and the DPF 26 to nitrogen, carbon dioxide, and water. During NOx reduction control, by intermittently adding fuel from the addition valve 46 to the exhaust after a certain period of time, the exhaust around the NOx catalyst has a temporarily low oxygen concentration and a large amount of unburned fuel components. The so-called rich spike is intermittently performed. As a result, the release and reduction of NOx from the NOx catalyst are promoted to reduce and purify the NOx.

  The S poison recovery control is performed in order to recover the NOx occlusion ability that has decreased due to the sulfur oxide (SOx) being occluded in the NOx catalyst. When the S poison recovery control is started, first, similarly to the PM regeneration control, the catalyst bed temperature is raised (for example, 600 to 700 ° C.) by continuously adding fuel from the addition valve 46 to the exhaust. The temperature rise control is performed. Thereafter, as in NOx reduction control, intermittent fuel addition from the addition valve 46 is performed, and intermittent rich spikes are performed to promote the release and reduction of SOx from the NOx catalyst, and The NOx occlusion capacity is restored.

  Incidentally, in the internal combustion engine 10, the post-injection by the fuel injection valve 40 may be performed during the regeneration control or when the catalyst bed temperature is increased in the S poison recovery control. This post-injection is an injection that is performed after fuel injection provided for combustion in the combustion chamber 13 such as main injection. Most of the fuel injected in such post-injection is burned in the combustion chamber 13. Without being discharged into the exhaust passage. Therefore, even by such post injection, it is possible to increase the amount of unburned fuel components in the exhaust gas and promote an increase in the catalyst bed temperature.

As described above, in this embodiment, the exhaust purification performance of the internal combustion engine 10 is maintained by adding fuel to the exhaust from the addition valve 46 provided in the exhaust passage.
As is well known, in the regeneration control, the SOOT accumulation amount PS, which is the amount of soot accumulated in the DPF 26, is estimated based on the engine operating state and the like. When the SOOT deposition amount PS becomes equal to or greater than a predetermined determination value A, fuel addition is executed and the DPF 26 is regenerated.

  Here, when the exhaust temperature, the cooling water temperature, or the like is low, the temperature increase due to the fuel addition is not sufficiently performed, and in some cases, surplus fuel may pass through the DPF 26 as it is and may be discharged from the exhaust passage as white smoke. is there. Therefore, if the exhaust temperature, the cooling water temperature, etc. are below a certain value, even if the SOOT accumulation amount PS is greater than or equal to the judgment value A, the fuel addition is prohibited, that is, the regeneration process of the DPF 26 is prohibited. Smoke emission can be suppressed. However, in this case, the following inconvenience may occur. For example, if low-speed driving is continuously performed or the engine is frequently stopped, fuel addition is prohibited even if the SOOT accumulation amount PS is equal to or greater than the determination value A. Therefore, the regeneration frequency of the DPF 26 Decreases and an excessive amount of SOOT is deposited on the DPF 26. If an excessive amount of SOOT accumulates on the DPF 26 in this way, the temperature of the DPF 26 may rise excessively and be damaged when the regeneration process is performed thereafter. In addition, when an excessive amount of SOOT accumulates in the DPF 26, a process for shifting to the fail-safe mode (for example, a process for reducing the fuel injection amount from the fuel injection valve 40) is performed, there is an opportunity to shift to the fail-safe mode. There is also a risk of an increase.

Therefore, in the present embodiment, the exhaust temperature and the cooling water temperature that permit the execution of the regeneration process are variably set as follows.
FIG. 2 shows a procedure for setting the regeneration execution flag F repeatedly performed at predetermined intervals by the electronic control unit 50. Note that the initial value of the regeneration execution flag F is “OFF”. When the regeneration process execution condition is satisfied, it is turned “ON” and the fuel addition as described above is executed. On the other hand, when the SOOT accumulation amount PS of the DPF 26 is reduced to a predetermined value or less due to the execution of fuel addition, the fuel supply is changed from “ON” to “OFF”, whereby the fuel addition is stopped and the regeneration process is completed.

  When this process is started, it is first determined whether or not the SOOT deposition amount PS is equal to or greater than the determination value A (S200). If the SOOT accumulation amount PS is equal to or greater than the determination value A (S100: YES), it is determined that the regeneration execution condition for the SOOT accumulation amount PS is satisfied, and then the cooling water temperature THW is determined as the execution determination value B. It is determined whether or not this is the case (S110). This execution determination value B is a value for determining whether or not the regeneration execution condition for the cooling water temperature is satisfied, and is set based on the current SOOT accumulation amount PS. For example, the current SOOT deposition amount PS is set to a lower value as the current SOOT deposition amount PS is larger, more specifically as the excess of the SOOT deposition amount PS from the determination value A is larger.

  If the coolant temperature THW is equal to or higher than the execution determination value B (S110: YES), it is determined that the regeneration execution condition for the coolant temperature THW is satisfied, and then the first exhaust temperature EXt1 is determined to be executed. It is determined whether or not the value is greater than or equal to value C (S120). This execution determination value C is a value for determining whether or not the regeneration execution condition for the exhaust temperature is satisfied, and is also set based on the current SOOT accumulation amount PS. For example, the current SOOT deposition amount PS is set to a lower value as the current SOOT deposition amount PS is larger, more specifically as the excess of the SOOT deposition amount PS from the determination value A is larger.

  When the first exhaust temperature EXt1 is equal to or higher than the execution determination value C (S120: YES), the regeneration execution conditions for the SOOT accumulation amount PS, the cooling water temperature THW, and the first exhaust temperature EXt1 are all satisfied. Therefore, the reproduction execution flag F is set to “ON” (S130), and this process is temporarily ended.

  Note that if a negative determination is made in each of the above steps S100 to S120, the regeneration execution condition is not satisfied, and therefore the regeneration execution flag F remains “OFF” without being set to “ON”. Thus, this process is temporarily terminated.

  By performing the regeneration execution flag setting process, when the SOOT accumulation amount PS exceeds the determination value A, the execution determination values for the cooling water temperature and the exhaust temperature are both lowered, so that all the regeneration execution conditions are satisfied. And the regeneration frequency of the DPF 26 can be increased. Note that in a state where the excess of the SOOT deposition amount PS from the determination value A is large and it is better to execute the regeneration process as early as possible, the execution determination value B and the execution determination value C are set lower. In this state, an opportunity for executing the reproduction process is preferably ensured.

  On the other hand, the oxidation state of SOOT during the regeneration process of the DPF 26 also changes depending on the intake air temperature and the atmospheric pressure. Therefore, if the addition amount at the time of fuel addition is not set in consideration of such points, in some cases, deterioration of fuel consumption due to an increase in regeneration time, excessive heating of the DPF 26 due to excessive progress of SOOT oxidation, Or there is a concern that the surplus of the added fuel etc. passes through the DPF 26 as it is and is discharged as white smoke.

  Therefore, in the present embodiment, the following addition amount calculation process is performed to optimize the addition amount T during execution of fuel addition, and thereby the regeneration process of the DPF 26 is performed more appropriately.

  FIG. 3 shows a processing procedure for the addition amount calculation processing. This process is repeatedly executed at predetermined intervals by the electronic control unit 50 during the regeneration process, that is, during the fuel addition.

When this process is started, first, the basic addition amount Tb is calculated based on the engine speed NE, the fuel injection amount Q from the fuel injection valve 40, and the target temperature PT of the DPF 26 (S200).
Next, the exhaust gas temperature correction amount Hex is calculated based on the exhaust gas temperature difference ΔEX (= first exhaust gas temperature EXt1−reference exhaust gas temperature EXb) between the first exhaust gas temperature EXt1 and the reference exhaust gas temperature EXb (S210).

  These reference exhaust temperature EXb and exhaust temperature correction amount Hex can be set to the following values, for example. First, the reference exhaust temperature EXb is a value set as appropriate. When the first exhaust temperature EXt1 and the reference exhaust temperature EXb are the same, that is, when the exhaust temperature difference ΔEX is “0”, the exhaust temperature correction amount Hex is set to “0”. Is set. Further, when the first exhaust temperature EXt1 is lower than the reference exhaust temperature EXb, the added fuel is difficult to burn and may become white smoke, so it is desirable to reduce the addition amount. Therefore, as the exhaust temperature difference ΔEX is a negative value and the absolute value thereof is larger, the exhaust temperature correction amount Hex is variably set so as to be a negative value. Conversely, when the first exhaust temperature EXt1 is higher than the reference exhaust temperature EXb, the added fuel is unlikely to become white smoke, so it is desirable to increase the addition amount to shorten the regeneration time of the DPF 26. Therefore, as the exhaust gas temperature difference ΔEX is a positive value and the absolute value thereof is larger, the exhaust gas temperature correction amount Hex is variably set so as to have a larger positive value.

Next, the intake air temperature correction amount Hin is calculated based on the intake air temperature difference ΔIN (= intake air temperature INt−reference intake air temperature INb) between the intake air temperature INt and the reference intake air temperature INb (S220).
These reference intake air temperature INb and intake air temperature correction amount Hin can be set to the following values, for example. First, the reference intake air temperature EXb is a value set as appropriate. When the intake air temperature INT and the reference intake air temperature INb are the same, that is, when the intake air temperature difference ΔIN is “0”, the intake air temperature correction amount Hin is set to “0”. The Further, when the intake air temperature INt is lower than the reference intake air temperature INb, the added fuel is difficult to burn and may become white smoke, so it is desirable to reduce the addition amount. Therefore, as the intake air temperature difference ΔIN is a negative value and the absolute value thereof is large, the intake air temperature correction amount Hin is variably set so as to become a negative large value. Conversely, when the intake air temperature INt is higher than the reference intake air temperature INb, the added fuel is unlikely to become white smoke, so it is desirable to increase the addition amount to shorten the regeneration time of the DPF 26. Therefore, as the intake air temperature difference ΔIN is a positive value and the absolute value thereof is larger, the intake air temperature correction amount Hin is variably set so as to become a larger positive value.

  Next, an atmospheric pressure correction amount Hap is calculated based on the atmospheric pressure AP (S230). The atmospheric pressure correction amount Hap can be set to the following value, for example. That is, in an environment where the atmospheric pressure is low, such as when traveling at high altitudes, the oxygen concentration in the atmosphere is low, so that the added fuel is difficult to burn and may become white smoke, so it is desirable to reduce the amount of addition. Therefore, as the atmospheric pressure AP is lower, the atmospheric pressure correction amount Hap is variably set to a smaller value of “1” or less.

Next, the addition amount T is calculated based on the following expression (1) (S240), and this process is temporarily terminated.

T = {((Tb + Hex) · K1) + (Hin · K2)} · (Hap · K3) (1)
T: addition amount Tb: basic addition amount Hex: exhaust temperature correction amount Hin: intake air temperature correction amount Hap: atmospheric pressure correction amount K1: first correction coefficient K2: second correction coefficient K3: third correction coefficient

The first correction coefficient K1 is a correction amount for the basic addition amount Tb and is variably set based on the SOOT deposition amount PS. The second correction coefficient K2 is a correction amount for the intake air temperature correction amount Hin, and is also variably set based on the SOOT accumulation amount PS. The third correction coefficient K3 is a correction amount for the atmospheric pressure correction amount Hap, and is also variably set based on the SOOT deposition amount PS.

  These correction coefficients K1, K2, and K3 are set for the following reasons. For example, during the regeneration process, as the SOOT deposition amount PS is larger, more SOOT oxidation heat is generated, so that the amount of fuel added can be reduced. In consideration of these points, for example, as shown in FIGS. 4 to 6, the correction coefficients K1, K2, and K3 are such that the SOOT deposition amount is such that the smaller the SOOT deposition amount PS is, the smaller the value is “1” or less. The amount of addition T is reduced as the SOOT deposition amount PS is increased.

According to this embodiment described above, the following effects can be obtained.
(1) As a correction amount for the basic addition amount T, a second correction coefficient K2 is calculated based on the SOOT accumulation amount PS, and the second correction coefficient K2 is multiplied by the intake air temperature correction amount Hin [Expression (1) The second term of the right side: (Hin · K2)], the correction amount based on the SOOT accumulation amount PS and the intake air temperature INT is calculated.

  Further, as a correction amount for the basic addition amount T, a third correction coefficient K3 is calculated based on the SOOT accumulation amount PS, and the atmospheric pressure correction amount Hap is multiplied by the third correction coefficient K3 [Expression (1) The third term on the right side: (Hap · K3)], and the correction amount based on the SOOT deposition amount PS and the atmospheric pressure AP is calculated.

  As described above, in this embodiment, the correction amount of the addition amount is calculated in consideration of not only the SOOT accumulation amount but also the intake air temperature and the atmospheric pressure that affect the oxidation state of the SOOT in the DPF 26. Therefore, the regeneration of the DPF 26 can be performed more suitably.

  (2) As a correction amount for the basic addition amount T, a first correction coefficient K1 is calculated based on the SOOT accumulation amount PS, and the exhaust gas temperature correction amount Hex and the basic addition amount T are multiplied by the first correction coefficient K1. [First term on the right side of equation (1): ((Tb + Hex) · K1)], the basic addition amount T is corrected by the SOOT deposition amount PS. Therefore, this also makes it possible to perform the regeneration of the DPF 26 more suitably.

  (3) The execution determination values B and C constituting the regeneration execution condition of the DPF 26 are variably set based on the SOOT accumulation amount PS. Therefore, the regeneration frequency of the DPF 26 can be increased particularly in a situation where the exhaust gas temperature and the cooling water temperature are low.

In addition, the said embodiment can also be changed and implemented as follows.
-Calculation of the exhaust gas temperature correction amount Hex may be omitted. Further, the calculation of the first correction coefficient K1 may be omitted.

  The calculation of the correction amount based on the SOOT accumulation amount PS and the intake air temperature INT may be omitted by omitting the second term (Hin · K2) on the right side of the above equation (1). Further, the third term (Hap · K3) on the right side of the equation (1) may be omitted, and the calculation of the correction amount based on the SOOT deposition amount PS and the atmospheric pressure AP may be omitted.

The calculation of one of the second correction coefficient K2 and the third correction coefficient K3 may be omitted.
Each setting mode of the execution determination value B, the execution determination value C, the exhaust temperature correction amount Hex, the intake air temperature correction amount Hin, the atmospheric pressure correction amount Hap, and the first to third correction coefficients K1 to K3 is an example, and is appropriately Can be changed. Further, the above formula (1) can be appropriately changed as long as the addition amount T can be calculated in the same manner.

  Only one of the execution determination value B and the execution determination value C may be variably set. Further, it is not always necessary to variably set the execution determination value B and the execution determination value C. Even in this case, the effects described in (1) and (2) can be obtained.

-The NOx catalytic converter 25, DPF 26, and oxidation catalytic converter 27 are provided in the exhaust passage.
Even if the NOx catalytic converter 25 and the oxidation catalytic converter 27 are other catalytic converters, or the DPF 26 is a so-called DPNR converter carrying a NOx storage reduction catalyst, the present invention is similarly applied. be able to. Moreover, the arrangement | positioning aspect and number of said each converter and filter can be changed suitably.

  DESCRIPTION OF SYMBOLS 10 ... Internal combustion engine, 11 ... Turbocharger, 12 ... Intake passage, 13 ... Combustion chamber, 14 ... Exhaust passage, 15 ... Air cleaner, 16 ... Air flow meter, 17 ... Compressor, 18 ... Intercooler, 19 ... Intake throttle valve, 20 Intake manifold, 21 ... Intake port, 22 ... Exhaust port, 23 ... Exhaust manifold, 24 ... Exhaust turbine, 25 ... NOx catalytic converter, 26 ... DPF, 27 ... Oxidation catalytic converter, 28 ... First exhaust temperature sensor, 29 ... Second exhaust temperature sensor, 30 ... differential pressure sensor, 32 ... oxygen sensor, 33 ... EGR passage, 34 ... EGR catalyst, 35 ... EGR cooler, 36 ... EGR valve, 40 ... fuel injection valve, 41 ... high pressure fuel supply pipe, 42 ... Common rail, 43 ... Fuel pump, 44 ... Rail pressure sensor, 45 ... Low pressure fuel supply pipe, 46 ... Addition valve, 50 ... Electronic control Location, 51 ... engine rotational speed sensor, 52 ... accelerator sensor, 53 ... throttle valve sensor, 54 ... intake air temperature sensor, 55 ... water temperature sensor, 56 ... atmospheric pressure sensor.

Claims (1)

An exhaust purification member that is provided in an exhaust passage of the internal combustion engine and collects particulate matter in the exhaust gas, and when the amount of particulate matter accumulated in the exhaust purification member exceeds a predetermined amount, fuel is added to the exhaust purification member In the exhaust purification device of the internal combustion engine for calculating the correction amount for the basic addition amount when setting the addition amount at the time of fuel addition,
As the correction amount, at least one of a correction amount based on the accumulation amount and the intake air temperature and a correction amount based on the accumulation amount and the atmospheric pressure is calculated.

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