JP4285080B2 - Exhaust gas purification device for internal combustion engine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an exhaust gas purification device for an internal combustion engine, and more particularly to a control technique for regenerating a particulate filter.
[0002]
[Prior art]
In recent years, internal combustion engines mounted on automobiles and the like have been required to improve exhaust emissions. In particular, compression ignition type diesel engines using light oil as a fuel are included in exhaust gas in addition to CO, HC and NOx. It is necessary to remove exhaust particulates such as soot and SOF. For this reason, the particulate filter is disposed in the exhaust passage through which the exhaust gas discharged from the cylinder of the internal combustion engine body flows, and the exhaust particulates in the exhaust gas are collected here.
[0003]
The particulate filter allows the inflowing exhaust gas to permeate through the porous partition walls, and at that time, collects exhaust particulates in the exhaust gas through the surfaces and pores of the partition walls. When the amount of collection increases excessively, the back pressure of the internal combustion engine body increases due to an increase in flow resistance in the particulate filter, resulting in a decrease in output. For this reason, it is necessary to restore the exhaust particulate collection capability of the particulate filter by executing a regeneration process that appropriately removes the exhaust particulate collected by the particulate filter.
[0004]
A particulate filter that can be regenerated during operation of the internal combustion engine is one in which an oxidation catalyst such as platinum is provided on the particulate filter and the oxidation action of the oxidation catalyst is utilized. The regeneration process is based on the post-injection for injecting fuel during the expansion stroke, or by retarding the intake valve and retarding the timing of normal fuel injection.
[0005]
In Patent Document 1 and Patent Document 2 below, regeneration starts by utilizing the fact that the differential pressure between the inlet and outlet of the particulate filter increases due to the increase in the ventilation resistance due to the increase in the collection amount of exhaust particulates. What determines time etc. is disclosed.
[0006]
[Patent Document 1]
JP-A-7-189654 [Patent Document 2]
Japanese Patent Laid-Open No. 8-303290
[Problems to be solved by the invention]
However, since the regeneration process of the particulate filter such as the post injection acts in the direction of changing the output torque, the net output torque taken out before and after the regeneration start and regeneration end is not smoothly connected to the driver. May give a sense of incongruity.
[0008]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an exhaust gas purifying device for an internal combustion engine that can reduce an uncomfortable feeling of an occupant at the start of regeneration or at the end of regeneration.
[0009]
[Means for Solving the Problems]
The invention according to claim 1 is a filter that collects exhaust particulates in the exhaust gas in the middle of an exhaust passage through which exhaust gas exhausted from a cylinder of the internal combustion engine main body flows. The particulate filter has a particulate filter that can be regenerated so that exhaust particulates can be collected by performing a regeneration process that removes the particulates, and the start time of the regeneration process indicates the collection state of exhaust particulates in the particulate filter. In an exhaust gas purification apparatus for an internal combustion engine that monitors and determines the amount of collected state,
When the collection state amount reaches a regeneration start reference value at which the regeneration process should be started, regeneration start permission means for permitting the start of the regeneration process;
Regeneration start reservation means for reserving the start of the regeneration process is provided on condition that the output torque of the internal combustion engine body is equal to or greater than a predetermined threshold value.
[0010]
If the output torque is equal to or less than the output torque in the no-load balanced state, the shaft output torque of the internal combustion engine body is substantially 0, and the fluctuation of the shaft output torque before and after the start of regeneration is small. Therefore, by keeping the start of the regeneration process when the output torque of the internal combustion engine body is equal to or greater than a predetermined threshold, it is possible to reduce the start of the regeneration process under conditions where the shaft output torque is likely to fluctuate. Thereby, a passenger | crew's discomfort can be reduced.
[0011]
According to the first aspect of the present invention, in the above configuration, when the collection state amount reaches a regeneration start forcing value in which the collection amount is larger than the regeneration start reference value, the reserved state at the start of the regeneration process is released. The reproduction start reservation canceling means is provided.
[0012]
If the collection state amount reaches the regeneration start reference value and the regeneration start is retained too much, the exhaust particulate collection amount becomes excessive, the back pressure of the internal combustion engine body increases, Cause combustion. By forcing the start of the regeneration process when the regeneration start forced value is reached, it is possible to avoid an excessive collection amount of exhaust particulates.
[0013]
The invention according to claim 2 is a filter that collects exhaust particulates in the exhaust gas in the middle of an exhaust passage through which exhaust gas discharged from the cylinder of the internal combustion engine main body flows, the collected exhaust gas It has a particulate filter that can be regenerated so that exhaust particulates can be collected by performing a regeneration process to remove the particulates, and the end time of the regeneration process is shown as a trap that indicates the collection state of exhaust particulates in the particulate filter. In an exhaust gas purification apparatus for an internal combustion engine that monitors and determines the amount of collected state,
When the collection state amount reaches the regeneration end reference value at which the regeneration process is to be terminated, regeneration end permission means for permitting the end of the regeneration process;
Regeneration completion reservation means for reserving completion of the regeneration process is provided on condition that the output torque of the internal combustion engine body is equal to or greater than a predetermined threshold value.
[0014]
If the output torque is equal to or less than the output torque in the no-load balance state, the shaft output torque of the internal combustion engine body is substantially 0, and the fluctuation of the shaft output torque before and after the end of regeneration is small. Therefore, when the output torque of the internal combustion engine body is greater than or equal to a predetermined threshold, the end of the regeneration process is reserved, so that the end of the regeneration process under conditions where the shaft output torque is likely to fluctuate can be reduced. Thereby, a passenger | crew's discomfort can be reduced.
[0015]
According to a third aspect of the present invention, in the configuration of the second aspect of the invention, when the collection state amount reaches a regeneration end forcing value with a collection amount less than the regeneration end reference value, the regeneration process is terminated. Regeneration end reservation canceling means for canceling the reserved state is provided.
[0016]
After the collection state amount reaches the regeneration end reference value, if the suspension of the regeneration end continues excessively, unnecessary regeneration processing (post-injection or the like) is performed, and fuel consumption and the like deteriorate. By forcing the end of the playback process when the playback end forced value is reached, the unnecessary playback process can be avoided.
[0017]
According to a fourth aspect of the invention, in the configuration of the first or third aspect of the invention, it is determined whether or not the internal combustion engine body has been warmed up, and only when the negative determination is made, the regeneration start reservation means or the regeneration A reservation control means for enabling the end reservation means is provided.
[0018]
When the cold state is removed, the friction torque is stabilized and the controllability of the output torque is improved. Therefore, the change in the shaft output torque at the start and end of the regeneration can be made smaller than that in the cold state. . Therefore, it is possible to expand the degree of freedom of the start time or the end time of the reproduction while ensuring a certain effect of smoothly connecting the shaft output torque.
[0019]
According to a fifth aspect of the present invention, in the configuration of the first to fourth aspects of the present invention, the threshold value is a torque value in a no-load balanced state.
[0020]
If the output torque is equal to or less than the torque value in the no-load balanced state, the shaft output torque is substantially zero, and the passenger feels uncomfortable.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
FIG. 1 shows the configuration of a diesel engine according to a first embodiment to which the present invention is applied. In the diesel engine, an intake passage 2 through which intake air flows and an exhaust passage 3 through which exhaust gas from a cylinder of the engine body 1 flows are connected to the engine body 1, and a particulate filter 4 is disposed in the middle of the exhaust passage 3. Is provided.
[0022]
The particulate filter 4 is formed by sealing the flow path of a honeycomb body made of a porous ceramic such as cordierite or silicon carbide to form a filter main body, and from each cylinder of the engine main body 1 flowing from the inlet 4a. Exhaust gas flows through the porous partition and flows downstream from the outlet 4b. At this time, in the particulate filter 4, exhaust particulates contained in the exhaust gas are collected and accumulate as the operation time passes. An oxidation catalyst mainly composed of a noble metal such as platinum or palladium is supported on the surface of the filter body of the particulate filter 4. By oxidizing and removing the exhaust particulates under a predetermined temperature condition by the action of the oxidation catalyst, the particulate filter 4 is regenerated so that the exhaust particulates can be collected again. The regeneration process for removing the exhaust particulates is performed by a known method such as post injection, intake valve throttling, or retarding. Hereinafter, the combustion mode involving regeneration processing of the particulate filter 4 is referred to as regeneration combustion, and the combustion mode not involving regeneration processing is referred to as normal combustion.
[0023]
An ECU 51 that controls each part of the engine such as an injector of the engine body 1 is provided. The ECU 51 is a general one configured mainly with a microcomputer, and includes a CPU, a RAM, a ROM, and the like.
[0024]
The ECU 51 receives signals from various sensors for determining the state of each part of the engine in a general diesel engine. The exhaust passage 3 is connected to a first branch passage 31a that branches right upstream of the particulate filter 4 and a second branch passage 31b that branches right downstream of the particulate filter 4, and both branch passages 31a. , 31b is configured to detect a differential pressure between the inlet 4a and the outlet 4b of the particulate filter 4 (hereinafter referred to as filter differential pressure as appropriate). The filter differential pressure is a pressure that increases as the amount of particulates collected in the particulate filter 4 (hereinafter, appropriately referred to as “PM trapped amount”) increases and the pressure loss increases.
[0025]
In addition, an air flow meter 53 is provided in the intake passage 2, and the flow rate of intake air (hereinafter referred to as “intake amount” as appropriate) is known from its output.
[0026]
Further, the engine speed is known from the output of the speed sensor 54. Further, the temperature of the cooling water (hereinafter referred to as “cooling water temperature” as appropriate) is known from the water temperature sensor 55, and the temperature of the engine oil (hereinafter referred to as “oil temperature” as appropriate) is known from the oil temperature sensor 56.
[0027]
FIG. 2 and FIG. 3 show the control contents executed by the ECU 51 regarding the regeneration process of the particulate filter 4. These are programs that start up at a predetermined cycle by a timer interrupt. The process of FIG. 2 is a process of monitoring the collection state of exhaust particulates in the particulate filter 4. First, in step S110, the filter differential pressure, the intake air amount, and the like are read, and the PM collection amount m, which is a collection state amount, is calculated based on these. The calculation is performed according to a known method, for example, a filter differential pressure and an intake air amount as input, and a PM trapping amount m corresponding to the map. The filter differential pressure increases as the amount of PM trapped increases, and the filter differential pressure increases as the amount of intake air increases for the same amount of PM trapped. Therefore, the map captures PM as the filter differential pressure and the amount of intake air increase. It becomes a map of the tendency that quantity increases.
[0028]
In step S120, if the regeneration process is not currently being executed, that is, normal combustion, the PM collection amount m is compared with the regeneration start reference value mA, and the PM collection amount m is greater than the regeneration start reference value mA. It is determined whether or not. If an affirmative determination is made in step S120, a normal / regenerative combustion switching permission flag F1 indicating that permission for switching between normal combustion and regenerative combustion (hereinafter, referred to as normal / regenerative combustion switching permission) is permitted in step S130. Set. In this case, the normal / regenerative combustion switching permission is switching from normal combustion to regenerative combustion.
[0029]
On the other hand, if the regeneration process is currently being executed, that is, regeneration combustion, in step S120, the PM collection amount m is compared with the regeneration end reference value mC, and the PM collection amount m is determined from the regeneration end reference value mC. It is determined whether or not it is smaller. If an affirmative determination is made in step S120, a normal / regenerative combustion switching permission flag F1 is set in step S130. The normal / regenerative combustion switching permission in this case is switching from the regenerative combustion to the normal combustion.
[0030]
If a negative determination is made in step S120, step S130 is skipped and the normal / regenerative combustion switching permission flag F1 is not set. The normal / regenerative combustion switching permission flag F1 is reset when normal / regenerative combustion switching (step S240), which will be described later, is performed.
[0031]
Here, if the regeneration start reference value mA is too low, the frequency of regeneration processing will be excessive, and if it is too high, the back pressure of the engine body 1 may increase or rapid combustion may occur during regeneration processing. To set. If the reproduction end reference value mC is too high, the frequency of reproduction processing is excessive, and if it is too low, meaningless reproduction processing may be performed.
[0032]
FIG. 3 is a flow for switching between normal / regenerative combustion, which starts after the processing of FIG. Step S210 is processing as regeneration start permission means and regeneration end permission means, and it is determined whether or not the normal / regeneration combustion switching permission flag F1 is set. If a negative determination is made, this flow ends. If a positive determination is made in step S210, the process proceeds to step S220. Step S220 is processing as a reservation control means, and determines whether or not it is after warm-up, that is, whether or not the cold state is removed. Whether or not it is after warming up is compared with a preset threshold value of the coolant temperature or oil temperature, and if it is higher than the threshold value, it is determined that it has been warmed up, and if it is lower, it is determined that it is still warming up.
[0033]
If the engine is still warming up and the determination in step S220 is negative, the process proceeds to step S230. Step S230 is processing as the regeneration start reservation means and the regeneration end reservation means, and determines whether or not the output torque is smaller than the torque value in the no-load balance state (hereinafter referred to as the no-load balance torque as appropriate).
[0034]
The determination is performed as follows, for example. When the temperature of the entire engine is low, the friction torque of the engine increases, so that a large value is given to the no-load balance torque that is a balance with this. Since the friction torque also increases as the engine speed increases, the higher the engine speed, the greater the no-load balance torque. Therefore, the fuel injection amount that gives the no-load balance torque in the operation state with the operation state defined by the coolant temperature, the oil temperature, and the engine speed as an input (hereinafter referred to as the no-load balance injection amount as appropriate). The corresponding map is stored in the ROM of the ECU 51, the current cooling water temperature, the oil temperature, and the injection amount at the time of no-load balance corresponding to the engine speed are read according to the map, and this is compared with the current fuel injection amount. To do. If the current fuel injection amount is smaller than the injection amount at the time of no-load balance, it is determined that the output torque is smaller than the no-load balance torque.
[0035]
If an affirmative determination is made in step S230 that determines whether or not the output torque is smaller than the no-load balance torque, normal / regenerative combustion switching is performed in step S240. That is, if the current combustion is normal combustion, the normal combustion is switched to regenerative combustion, and the regeneration is started. If the current combustion is regenerative combustion, the regenerative combustion is switched to normal combustion and the regeneration is terminated.
[0036]
On the other hand, when a negative determination is made in step S230 for determining whether or not the output torque is smaller than the no-load balance torque, the normal / regenerative combustion switching (step S240) is not performed. Therefore, even when the PM collection amount m exceeds the regeneration start reference value mA and the determination in step S210 is affirmative, the regeneration process of the particulate filter 4 is not started. Further, even when the PM collection amount m is below the regeneration end reference value mC and the determination in step S210 is affirmative, the regeneration process of the particulate filter 4 is not terminated.
[0037]
If the output torque is equal to or less than the no-load balancing torque, the output torque only balances with the friction torque. Therefore, even if the output torque changes due to normal / regenerative combustion switching, the shaft output torque does not change greatly. . Therefore, when the output torque is equal to or greater than the no-load balancing torque, the normal / regenerative combustion switching is retained, and the timing for executing the normal / regenerative combustion switching is no load when the gear position is changed or when the accelerator is decelerated. By limiting to when the torque is equal to or less than the balance torque, it is possible to prevent the driver from feeling uncomfortable without the shaft output torque being smoothly connected.
[0038]
Further, when an affirmative determination is made in step S220 for determining whether or not the engine has been warmed up, normal / regenerative combustion switching (step S240) is executed. After warm-up, the friction torque is stabilized without being affected by the temperature of the entire engine, and the controllability of the output torque is improved, unlike during the cold state where the engine is in a transient state such as temperature. To do. That is, it becomes easy to set the control conditions such as the fuel injection amount so that the shaft output torque is smoothly connected. Thereby, the change in the shaft output torque at the start and end of regeneration can be made smaller than that in the cold state. Therefore, it is possible to expand the degree of freedom of the start time or the end time of the reproduction while ensuring a certain effect of smoothly connecting the shaft output torque. Therefore, as in the present embodiment, regeneration can be started as soon as the amount of PM trapped exceeds the regeneration start reference value mA, and regeneration can be terminated as soon as it falls below the regeneration end reference value mC.
[0039]
(Second Embodiment)
4 and 5 show the control executed by the ECU of the diesel engine according to the second embodiment to which the present invention is applied. Except for the control executed by the ECU, the configuration is substantially the same as that of the first embodiment, and differences from the first embodiment will be mainly described. In addition, each part of the engine including the ECU will be described with the same number.
[0040]
If an affirmative determination is made in step S120 in which the PM collection amount m is compared with the regeneration start reference value mA or the regeneration end reference value mc, the process proceeds to step S121. In step S121, if the current combustion is normal combustion, it is determined whether or not the PM collection amount m is larger than the regeneration start forced value mB. The regeneration start forced value mB is set to a value larger than the regeneration start reference value mA. If the combustion is regenerative combustion, it is determined whether or not the PM collection amount m is smaller than the regeneration end forced value mD. The regeneration end forced value mD is set to a value smaller than the regeneration end reference value mC.
[0041]
If a negative determination is made in step S121, the normal / regenerative combustion switching permission flag F1 is set in step S130 as in the first embodiment. If a positive determination is made in step S121, the process proceeds to step S140, and the normal / regenerative combustion switching request flag F2 is set. If the PM collection amount m exceeds the regeneration start forced value mB, it has already exceeded the regeneration start reference value mA, and if the PM collection amount m falls below the regeneration end forced value mD, regeneration has already ended. Since it is below the reference value mC, when the normal / regenerative combustion switching request flag F2 is set, the normal / regenerative combustion switching permission flag F1 is already set.
[0042]
The normal / regenerative combustion switching permission flag F1 and the normal / regenerative combustion switching request flag F2 are both reset when the normal / regenerative combustion switching (step S240) is executed.
[0043]
FIG. 5 is a flowchart showing the contents of the normal / regenerative combustion switching. If the determination in step S210 for determining whether or not the normal / regenerative combustion switching permission flag F1 is set is affirmative, the process proceeds to step S211. Step S211 is processing as a regeneration start reservation canceling means and a regeneration end reservation canceling means, and it is determined whether or not the normal / regenerative combustion switching request flag F2 is set. If a negative determination is made in step S211, the process proceeds to step S220 for determining whether or not the engine has been warmed up, and thereafter, the same processing as in the first embodiment is executed.
[0044]
If a positive determination is made in step S211 for determining whether or not the normal / regenerative combustion switching request flag F2 is set, normal / regenerative combustion switching is performed in step S240.
[0045]
FIG. 6 and FIG. 7 each show a change over time in the amount of collected PM. FIG. 6 shows the particulate filter 4 repeatedly depositing exhaust particulates by collecting exhaust particulates and removing exhaust particulates by regeneration processing. FIG. 7 is an enlarged view of the situation before and after the end of the reproduction process.
[0046]
When the PM collection amount m reaches the regeneration start collection amount mA (point A), the normal / regeneration combustion switching permission flag F1 is first set. When the engine warm-up is completed or the output torque falls below the no-load balance torque, the normal combustion is switched to the regenerative combustion, and the regeneration process is started.
[0047]
On the other hand, if the condition for switching from normal combustion to regenerative combustion is not established (steps S220 and S230), the amount of collected PM increases during that time. When the PM collection amount m reaches the regeneration start forced value mB (point B), the normal / regenerative combustion switching request flag F2 is set and regeneration is forcibly started. Thereby, it can avoid that PM collection amount continues increasing excessively. Therefore, the regeneration start forcing value mB is set in consideration of the upper limit value of the amount of PM collected that can avoid problems such as rapid combustion. If the regeneration start reference value mA is too low, the frequency of regeneration increases. On the other hand, if the regeneration start reference value mA is too high, the margin for the regeneration start forced value mB is compressed, so that the output torque falls below the no-load balance torque. / The characteristic part of this exhaust gas purifying device that performs regenerative combustion switching cannot be fully utilized. The reproduction start reference value mA is preferably set in consideration of these.
[0048]
Next, when the regeneration process proceeds and the amount of collected PM m decreases and reaches the regeneration end reference value mC (point C), the normal / regenerative combustion switching permission flag F1 is first output. When the output torque falls below the no-load balance torque, the regeneration combustion is switched to the normal combustion, and the regeneration ends.
[0049]
On the other hand, if the condition for switching from regenerative combustion to normal combustion is not established (steps S220 and S230), the amount of collected PM m further decreases during that time. When the PM collection amount m reaches the regeneration end forced value mD (point D), the normal / regenerative combustion switching request flag F2 is set and the regeneration ends. Thereby, it is possible to avoid the meaningless reproduction process from continuing. Therefore, the regeneration end forced value mD is set in consideration of the lower limit value of the PM trapping amount that can avoid meaningless regeneration processing. If the regeneration end reference value mC is too high, the frequency of regeneration increases. On the other hand, if the regeneration end reference value mC is too low, the margin for the regeneration end forced value mD is compressed, and the output torque is less than the no-load balance torque. / The characteristic part of this exhaust gas purifying device that performs regenerative combustion switching cannot be fully utilized. The reproduction end reference value mC is preferably set in consideration of these.
[0050]
In each of the above embodiments, even if the normal / regenerative combustion switching is permitted by comparing the PM collection amount with the reference values (regeneration start reference value, regeneration end reference value), the predetermined retention condition is satisfied. If this is the case (step S230), normal / regenerative combustion switching is not performed, but this is the case for both switching from normal combustion to regenerative combustion and switching from regenerative combustion to normal combustion. For either switching from normal combustion to regenerative combustion, or switching from regenerative combustion to normal combustion, switch to normal / regenerative combustion as usual, when the PM accumulation amount reaches the reference value without reservation of normal / regenerative combustion switching. May be carried out.
[0051]
Also, after the engine is warmed up, normal / regenerative combustion switching is performed without reserving the start or end of regeneration, but even after the engine is warmed up, the output torque is more than the unloaded balanced torque. If larger, normal / regenerative combustion switching may be reserved. This is because even after the engine is warmed up, the driver may feel uncomfortable due to a change in shaft output torque caused by normal / regenerative combustion switching. Control in this case will be described with reference to FIG. 5. Step S220 may be omitted, and step S240 may be executed when step S230 is affirmed.
[0052]
Further, in step S230, the threshold for comparison with the output torque is set so that the occupant feels no sense of incongruity for the no-load balance torque, but this is not necessarily limited thereto. Here, it is not excluded to set the threshold value to be equal to or greater than the no-load balance torque, but it goes without saying that the frequency closer to the no-load balance torque can reduce the frequency at which the occupant feels uncomfortable.
[0053]
Moreover, although the PM collection amount is compared with the regeneration start reference value or the like, the start of regeneration or the like is permitted, but even if it is not the PM collection amount, the collection state of the exhaust particulates in the particulate filter 4 is determined. Any collection state quantity that can be represented can be used to determine whether or not to permit the start of regeneration or the like. For example, a filter differential pressure may be used.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of an internal combustion engine according to a first embodiment to which an exhaust gas purification apparatus of the present invention is applied.
FIG. 2 is a first flowchart showing details of control executed by an ECU that controls each part of the internal combustion engine.
FIG. 3 is a second flowchart showing details of control executed by an ECU that controls each part of the internal combustion engine.
FIG. 4 is a first flowchart showing the contents of control executed by an ECU that controls each part of an internal combustion engine according to a second embodiment to which the exhaust gas purification apparatus of the present invention is applied.
FIG. 5 is a second flowchart showing the contents of control executed by an ECU that controls each part of the internal combustion engine.
FIG. 6 is a first diagram illustrating the control content.
FIG. 7 is a second diagram for explaining the control content;
[Explanation of symbols]
1 Engine body (Internal combustion engine body)
2 intake passage 3 exhaust passage 4 particulate filter 51 ECU (regeneration start permission means, regeneration end permission means, regeneration start reservation means, regeneration end reservation means, regeneration start reservation release means, regeneration end reservation release means, reservation control means)
52 Differential Pressure Sensor 53 Air Flow Meter 54 Speed Sensor 55 Water Temperature Sensor 56 Oil Temperature Sensor

Claims (5)

A filter that collects exhaust particulates in the exhaust gas in the middle of an exhaust passage through which exhaust gas exhausted from a cylinder of an internal combustion engine body circulates, and performs a regeneration process to remove the collected exhaust particulates A particulate filter that can regenerate exhaust particulate so that the particulate matter can be collected, and the start timing of the regeneration process is determined by monitoring the collection state amount indicating the collection state of exhaust particulate in the particulate filter. In an exhaust gas purification device for an internal combustion engine,
When the collection state amount reaches a regeneration start reference value at which the regeneration process should be started, regeneration start permission means for permitting the start of the regeneration process;
A regeneration start retaining means for retaining the start of the regeneration processing on condition that the output torque of the internal combustion engine body is equal to or greater than a predetermined threshold ;
When the collection state amount reaches a regeneration start forcing value in which the collection amount is larger than the regeneration start reference value, a regeneration start reservation canceling unit that cancels the reserved state at the start of regeneration processing is provided. An exhaust gas purification device for an internal combustion engine. A filter that collects exhaust particulates in the exhaust gas in the middle of an exhaust passage through which exhaust gas exhausted from a cylinder of an internal combustion engine body circulates, and performs a regeneration process to remove the collected exhaust particulates And a particulate filter that can regenerate exhaust particulate so that the particulate matter can be collected, and the end time of the regeneration process is determined by monitoring the collection state amount indicating the collection state of exhaust particulate in the particulate filter. In an exhaust gas purification device for an internal combustion engine,
When the collection state amount reaches the regeneration end reference value at which the regeneration process is to be terminated, regeneration end permission means for permitting the end of the regeneration process;
An exhaust gas purifying device for an internal combustion engine, comprising: regeneration end reservation means for retaining the end of the regeneration process on condition that the output torque of the internal combustion engine body is equal to or greater than a predetermined threshold value . 3. The exhaust gas purifying apparatus for an internal combustion engine according to claim 2, wherein when the collection state amount reaches a regeneration end forcing value in which the collection amount is smaller than the regeneration end reference value, the reserved state at the end of the regeneration process is released. An exhaust gas purifying device for an internal combustion engine provided with a regeneration end reservation releasing means . 4. The exhaust gas purifying apparatus for an internal combustion engine according to claim 1 , wherein it is determined whether or not the internal combustion engine body has been warmed up, and only when the negative determination is made, An exhaust gas purifying apparatus for an internal combustion engine provided with reservation control means for making the means effective . The exhaust gas purification apparatus for an internal combustion engine according to any one of claims 1 to 4 , wherein the threshold value is a torque value in a no-load balanced state .

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