JP2002021536A - Exhaust emission control device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exhaust emission control apparatus and method capable of continuously heating a filter using a heating means even if the operation of stopping an engine is carried out during filter regeneration. SOLUTION: A casing 21 is provided on the exhaust flow passage of an engine 10 and a filter 23 for collecting particulates contained in exhaust emissions is provided therein. An electric heater 24 for burning the particulates accumulated on the filter 23 is provided on the upstream side of the filter 23. Should the engine 10 be controlled to a stop during regeneration of the filter 23, the filter is kept heated by the electric heater 24, by idling the engine 10, if the stop occurs within a predetermined time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust gas purifying apparatus and an exhaust gas purifying method for removing particulates contained in exhaust gas of a diesel engine.

[0002]

2. Description of the Related Art The number of automobiles has increased exponentially since the turn of the century, and the amount of exhaust gas emitted from internal combustion engines of automobiles has been increasing rapidly.
In particular, various substances contained in exhaust gas emitted from a diesel engine cause pollution, and are now seriously affecting the world environment. In addition, recently, it has been reported that particulate matter such as soot contained in exhaust gas sometimes causes allergic disorders and a decrease in sperm count. In other words, it is considered that taking measures to remove particulates in exhaust gas is an urgent task for humanity.

[0003] Under such circumstances, various types of exhaust gas purifying devices have been proposed. This type of exhaust gas purification device includes an exhaust gas purification filter in order to remove particulates and the like discharged from an internal combustion engine such as a diesel engine. If these filters are used for a long time, the load on the engine increases due to the accumulation of the particulates. Therefore, it is necessary to remove the particulates.

At present, an electric heater for heating the filter is provided at the upstream end of the filter. Then, the electric heater is energized for a certain period of time to heat the filter, so that the particulates are burned off and the filter is regenerated. The regeneration of the filter is performed only when the engine is started to secure the electric power of the electric heater.

[0005]

However, in the conventional exhaust gas purifying device, the engine may be stopped during the regeneration of the filter due to the driver's judgment, the condition of the vehicle, or the like. If the engine is stopped while the filter is regenerating, the power supplied to the electric heater cannot be secured.
The heating of the filter is also interrupted. As a result, particulates such as soot accumulated in the filter may leave ash and the like on the filter as combustion residues, which may result in poor regeneration. Then, even if the filter is to be regenerated next time, the regeneration rate is low, and if such a situation continues frequently, the trapping region of the particulates becomes narrow due to the combustion residue, and the frequency of the filter regeneration increases.

In addition, when the engine is stopped during regeneration of the filter and the engine is started immediately thereafter, if the filter temperature has already reached a predetermined temperature (550 ° C.) or more, the particulates are excessive. Causes burning.
As a result, the filter may be thermally damaged.

Further, if the engine is stopped during the regeneration of the filter, and the engine is started immediately thereafter to resume the regeneration, the time required for the regeneration is first reset. Therefore, if the engine is repeatedly stopped and started before the regeneration of the filter is completed, it takes a long time to complete the regeneration.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to continue heating a filter by a heating unit even when an operation for stopping an engine is performed during regeneration of a filter. An object of the present invention is to provide an exhaust gas purifying apparatus and an exhaust gas purifying method that can be performed.

[0009]

In order to solve the above-mentioned problems, according to the first aspect of the present invention, a casing provided on an exhaust flow path of an internal combustion engine, and a casing housed in the casing, the A filter for collecting the particulates contained in the exhaust gas to be discharged, and a heating means disposed upstream of the filter and burning the particulates deposited on the filter; In the filter exhaust gas purifying apparatus that regenerates the filter by heating the particulates by burning the particulates, control means for controlling on / off of the heating means is provided, and the control means controls the internal combustion during regeneration of the filter. The gist is that the heating by the heating means is continued for a predetermined time even when the engine is stopped.

According to a second aspect of the present invention, in the exhaust gas purifying apparatus according to the first aspect, the control means determines that the predetermined condition has been satisfied after the internal combustion engine has been stopped. The gist is that heating of the filter by the heating means is not continued.

According to a third aspect of the present invention, in the exhaust gas purifying apparatus according to the second aspect, a timer for measuring an elapsed time since the heating means is turned on is provided, and the elapsed time measured by the timer is provided. If the time has not reached the predetermined time, the control means turns off the heating means.

According to a fourth aspect of the present invention, in the exhaust gas purifying apparatus according to the second aspect, a temperature sensor for measuring a temperature of the heating means is provided, and a temperature detected by the temperature sensor becomes a predetermined temperature. If not, the gist is that the control means turns off the heating means.

According to the fifth aspect of the present invention, the first to fourth aspects are provided.
In the exhaust gas purifying apparatus described in any one of the above, the gist is that a stopping means for forcibly stopping the internal combustion engine is provided.

According to the sixth aspect of the present invention, the first to fifth aspects are provided.
The exhaust gas purifying apparatus according to any one of the preceding claims, further comprising storage means for storing an elapsed time from when the heating means is turned on, and after the internal combustion engine is stopped during regeneration of the filter, the internal combustion engine is restarted. Is started, the control means calculates a regeneration time required to regenerate the filter based on the elapsed time stored in the storage means, and turns on the heating means for the calculated regeneration time. Is the gist.

According to the present invention, the casing provided on the exhaust flow path of the internal combustion engine and the particulates contained in the casing and contained in the exhaust gas discharged from the internal combustion engine are collected. A filter, and heating means disposed upstream of the filter and burning the particulates deposited on the filter, and heating the filter with the heating means to burn the particulates, thereby forming the filter. In the filter exhaust gas purifying method configured to regenerate, even if the internal combustion engine is stopped during regeneration of the filter, if the predetermined condition is satisfied, the heating unit heats the filter while continuing to drive the internal combustion engine. The gist is that you have done it.

Hereinafter, the "action" of the present invention will be described. According to the first aspect of the present invention, even when the internal combustion engine is stopped during regeneration of the filter, the filter is continuously heated for a predetermined time by the control unit that controls the heating unit to be turned on and off. Therefore, for example, even if the operation of stopping the internal combustion engine is performed during the regeneration of the filter due to the driver's judgment, the state of the vehicle, or the like, the heating of the filter is not interrupted. Therefore, particulates such as soot accumulated in the filter can be completely burned, and they can be prevented from remaining on the filter as combustion residues.

According to the second aspect of the present invention, if the predetermined condition is satisfied after the internal combustion engine is stopped, the heating of the filter by the heating means is not continued by the control means. As described above, since the control unit determines whether or not to continue heating the filter, the regeneration of the filter is performed accurately. As a result, the reproduction efficiency can be improved.

According to the third aspect of the present invention, if the elapsed time from when the heating means is turned on has not reached the predetermined time, the heating means is turned off by the control means. In short, even if an expensive temperature sensor is not used, it is possible to know the temperature to which the heating means is heated by the elapsed time.

According to the present invention, when the temperature detected by the temperature sensor has not reached the predetermined temperature, the heating means is turned off by the control means. Therefore, since the temperature to which the heating means is heated can be known from the elapsed time, the continuation of heating according to the temperature of the heating means is determined. Therefore, the energy efficiency required for regeneration can be improved, and excess energy can be prevented from being consumed.

According to the fifth aspect of the present invention, since the stopping means for forcibly stopping the internal combustion engine is provided, the filter can be stopped when it is necessary to make an emergency stop due to the judgment of the driver or the condition of the vehicle. To stop the regeneration of the internal combustion engine, the internal combustion engine can be stopped.

According to the present invention, the elapsed time from when the heating means is turned off to when the heating of the filter is interrupted is stored by the storage means. Therefore, if the regeneration of the filter is interrupted and then the internal combustion engine is started again, the control means calculates the regeneration time required to regenerate the filter based on the elapsed time stored in the storage means. The heating means is turned on for the calculated time. As a result, since the time required for the reproduction is not the time from the beginning, the reproduction can be completed efficiently in a short time.

According to the seventh aspect of the present invention, when the internal combustion engine is stopped during regeneration of the filter, if the predetermined condition is satisfied, the driving of the internal combustion engine is continued while the filter is heated by the heating means. Heated. Therefore, even if the internal combustion engine is stopped during the regeneration of the filter due to the driver's judgment, the state of the vehicle, or the like, if the heating means is an electric heater or the like, the supplied power can be secured. . Therefore, the filter can be regenerated without applying a load to the battery mounted on the vehicle.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a regeneration system S for an exhaust gas purification device. The regeneration system S of the exhaust gas purification device includes an exhaust gas purification device 20 that is branched and installed in the exhaust passage 11 from a diesel engine 10 as an internal combustion engine. The exhaust gas purifying honeycomb filters 23 are accommodated in the casings 21 of the respective exhaust gas purifying devices 20.

Each filter 23 is made of porous silicon carbide (Si)
The exhaust gas purifying catalyst is carried by the sintered body of C). The filter 23 has a very high thermal conductivity. Therefore, the heat quantity of the exhaust gas is effectively transmitted to the rear of the filter 23 and the radial direction. Therefore, even if local excessive combustion occurs, heat can be safely diffused.

In each casing 21, a filter 23 is provided.
An electric heater 24 is provided as heating means for heating. Each of the electric heaters 24 is a spiral resistance heater arranged close to the gas upstream end face of the filter 23, and is supplied with electric power from a battery mounted on the vehicle. In the middle of the exhaust passage 11, a pressure sensor 2 is provided at an upstream side and a downstream side of each filter 23.
7a and 27b are provided.

Next, the electrical configuration of the regeneration system S of the exhaust gas purifying apparatus configured as described above will be described. As shown in FIG. 1, the pressure sensors 27a and 27b
A back pressure value of the exhaust gas at each of an upstream portion and a downstream portion of the filter 23 is detected, and a detection signal is output to a control circuit 30 as control means. Based on the detection result, the control circuit 30 calculates the pressure loss,
The amount of particulates such as soot deposited on the filter 23 can be detected. The pressure loss means that the filter 23
The value obtained by subtracting the back pressure value on the downstream side from the back pressure value on the upstream side. That is, it can be said that the higher the pressure loss, the larger the amount of particulates deposited on the filter 23.

An ignition device 35 such as an igniter for igniting a spark plug provided in the engine 10 is connected to a relay 37 as a stopping means for turning on and off the ignition device. The opening and closing of the relay 37 is controlled by the control circuit 30. When the relay 37 is turned on, the ignition device 35 is maintained in the on state regardless of the on / off state of the ignition switch 36 connected to the ignition device 35.

The key inserted into the ignition switch 36 is rotated by operating the key to
The position can be switched between a CK position, an ACC (accessory) position, an ON (ignition ON) position, and an ST (starter drive) position. Then, when the key is switched to the ST position, power is supplied to the electric heater 24. In short, power is supplied to the electric heater 24 only when the engine 10 is driven.

The control circuit 30 as a storage means has a memory, in which various control programs necessary for the operation of the regeneration system S of the exhaust gas purifying apparatus are stored. Further, the memory temporarily stores data obtained with the execution of the control program. Specifically,
The elapsed time from the start of the regeneration of the filter 23 and the time from the stop of the engine 10 are temporarily stored. Then, when the engine 10 is restarted after the engine 10 is stopped during the regeneration of the filter 23, the control circuit 30 calculates the remaining regeneration time based on the elapsed time stored in the memory.

An indicator 38,
A reproduction stop switch 39 is provided. The indicator 38 indicates whether or not the filter 23 is being reproduced, the reproduction time of the filter 23, and whether or not the reproduction of the filter 23 is abnormal. The regeneration stop switch 39 is operated when the regeneration of the filter 23 is forcibly stopped.

Next, the operation of the regeneration system S of the exhaust gas purifying apparatus configured as described above will be described with reference to the flowchart shown in FIG. (When the engine is stopped after 15 minutes have elapsed)
When the pressure loss of the exhaust gas increases and the amount of particulates deposited on the filter 23 approaches the maximum allowable deposition amount,
The indicator 38 lights up and the electric heater 24
Is turned on (S1, S2). When the electric heater 24 is turned on, a timer (not shown) built in the control circuit 30 is started, and the regeneration time of the filter 23 is measured.

In this state, the ignition switch 36 is turned off to stop the engine 10 according to the driver's judgment or the condition of the vehicle (S3). If 15 minutes or more have elapsed since the start of the regeneration of the filter 23 at the time of this operation (S4), the relay 37 remains closed, and the engine 10 remains in the after-idling state (S5). ). That is, even though the ignition switch 36 is turned off,
Since the driving of the engine 10 is continued, the filter 2
The reproduction of No. 3 is continued. The reason why the time is set to 15 minutes after the start of the regeneration of the filter 23 is that the electric heater 24 reaches the maximum temperature. When the regeneration time of the filter 23 has elapsed for 45 minutes (S6), the relay 37 is opened and the engine 10 is stopped. As a result, the power supply to the electric heater 24 is cut off,
Is ended.

(In the case where the engine is stopped with the regeneration time shorter than 15 minutes) In the above-mentioned S4, when the ignition switch 36 is turned off, if less than 15 minutes after the regeneration of the filter 23 is started (S4). , The relay 37 is opened and the engine 10 is stopped as usual (S1).
0). As a result, energization of the electric heater 24 is cut off, and regeneration of the filter 23 is interrupted. This is because the filter 23 has not yet been sufficiently heated to burn the particulates, so that there is no problem even if the electric heater 24 is turned off.

(When the engine is restarted after the engine is stopped) Thereafter, in order to restart the engine 10 according to the driver's judgment or the condition of the vehicle, the ignition switch 36 is turned on (S11), and the engine is started. Is performed (S12). When this operation is performed, the above S1
If two minutes or more have elapsed since the engine was stopped at 1 (S13), the following processing is performed. That is, the elapsed time during which the filter 23 has been regenerated before the engine 10 is stopped is called from the memory incorporated in the control circuit 30, and the remaining regenerative time required for the regeneration is calculated (S1).
4). Then, during the remaining reproduction time, the electric heater 24 is energized (S15).

(When the engine is forcibly stopped in an emergency) If the ignition switch 36 is not turned off in S3 (S3) and the reproduction stop switch 39 is turned on (S20), the process proceeds to S10. Transition. That is, the engine 10 is stopped and the filter 23
Playback is forcibly interrupted.

Therefore, according to the present embodiment, the following effects can be obtained. (1) In the exhaust gas purifying apparatus 20 of the present embodiment, a control circuit 30 that controls on / off of the electric heater 24 is provided. During the regeneration of the filter 23, the engine 10
Is operated by the control circuit 30, the heating by the electric heater 24 is continued for a predetermined time. Therefore, even if there is an operation to stop the engine 10 due to the judgment of the driver or the situation of the vehicle during the regeneration of the filter 23,
That is, even if the ignition switch 36 is turned off, the heating of the filter is not interrupted. Therefore, particulates such as soot accumulated in the filter 23 can be completely burned, and it is possible to prevent them from remaining on the filter 23 as combustion residues. As a result, a reproduction failure can be prevented, and a reduction in the reproduction rate can be prevented even when the filter 23 is to be reproduced next time. Moreover,
Since the combustion residue can be prevented from remaining on the filter 23,
The collection area of particulates does not become narrow, and the filter 2
3 can be reproduced less frequently.

(2) Exhaust gas purifying apparatus 20 of this embodiment
If the predetermined condition is not satisfied after the ignition switch 36 is turned off to stop the engine 10, the heating of the filter 23 by the electric heater 24 is not continued. That is, the control circuit 30 can determine whether or not to continue the heating of the filter 23.
Therefore, the regeneration of the filter 23 can be performed in an accurate state, and the regeneration efficiency can be improved. As a result, even if the ignition switch 36 is turned off under any circumstances, the substance accumulated in the filter 23 can be completely burned, and the filter 23 can be efficiently regenerated and the operation by the driver can be omitted.

(3) Exhaust gas purifying device 20 of the present embodiment
In the control circuit 30, a timer that measures the time since the electric heater 24 is turned on, that is, the elapsed time from when the filter 23 starts regeneration is built in the control circuit 30. Then, it is possible to know the temperature to which the electric heater 24 is heated by the elapsed time. That is,
A predetermined time (15 minutes) elapsed time measured by the timer since the ignition switch 36 was turned off.
If it has not elapsed, it is considered that the temperature of the electric heater 24 has not reached near the maximum value, and the electric heater 24 is stopped. Therefore, if the electric heater 24 has reached the maximum temperature, the heating of the electric heater 24 is continued, so that the energy efficiency required for the regeneration can be improved, and unnecessary energy can be prevented from being consumed. Further, since the temperature of the electric heater 24 can be predicted by the timer, it is not necessary to perform an expensive temperature sensor, a component for attaching the temperature sensor, and a process for attaching the temperature sensor to the casing 21. Therefore, the temperature of the electric heater 24 can be measured at low cost.

(4) Exhaust gas purifying device 20 of this embodiment
A regeneration stop switch 39 for forcibly stopping the engine 10 is provided. Therefore, even when it is necessary to make an emergency stop due to the driver's judgment or the situation of the car,
The engine 10 can be forcibly stopped to interrupt the regeneration of the filter 23.

(5) Exhaust gas purifying device 20 of the present embodiment
Then, when the electric heater 24 is turned off and the heating of the filter 23 is interrupted, the remaining regeneration time required to regenerate the filter 23 is calculated. Therefore, the time required for the reproduction is not reset first, so that the reproduction can be completed in a short time.

(6) Exhaust gas purifying device 20 of the present embodiment
Then, when the engine 10 is stopped during the regeneration of the filter 23 and immediately after that, the engine 10 is started again, the control circuit 30 turns on the electric heater 24 for the regeneration time stored in the memory. Therefore, even if the engine 10 is repeatedly stopped and started before the regeneration of the filter 23 is completed, the energizing time of the electric heater 24 can be minimized, so that unnecessary energy consumption can be eliminated. In addition, the regeneration failure of the filter 23 can be reduced.

(7) Exhaust gas purifying device 20 of this embodiment
Then, the electric heater 24 is used only for the regeneration time stored in the memory.
Is turned on, the control circuit 30 stops the engine 10. Therefore, the driver can leave the place without worrying about the regeneration state of the filter 23.

(8) In the exhaust gas purifying method of this embodiment, even if the engine 10 is stopped during regeneration of the filter 23, the electric heater 24 keeps the engine 10 running if the predetermined condition is satisfied. 23 is heated. Therefore, even if the engine 10 is stopped during the regeneration of the filter 23 due to the driver's judgment, the state of the vehicle, or the like, the power supply to the electric heater 24 can be secured. Therefore, the power supply to the electric heater 24 can be stabilized, and the filter 23 can be heated without increasing the size of the battery mounted on the automobile or applying a large load to the battery.

(Second Embodiment) Next, a second embodiment of the present invention will be described focusing on parts different from the first embodiment.

In the second embodiment, as shown in FIG. 3, near the electric heater 24 in each casing 21,
A temperature sensor 26 is provided. This temperature sensor 26
Detects the temperature of the electric heater 24 and outputs a detection signal to the control circuit 30. The control circuit 30 turns on the electric heater 24 by outputting a drive signal to the electric heater 24.

During regeneration of the filter 23, the ignition switch 36 is turned off in order to stop the engine 10 depending on the driver's judgment or the condition of the vehicle. When this operation is performed, if the temperature of electric heater 24 detected by temperature sensor 26 is equal to or higher than a predetermined temperature, that is, a temperature near the maximum value (600 to 900 ° C.), relay 37 is maintained in a closed state. , The engine 10 remains after idling. That is, as described in the first embodiment, the regeneration of the filter 23 is not interrupted. On the other hand, if the temperature of the electric heater 24 is lower than the predetermined value when the ignition switch 36 is turned off, the relay 37 is opened and the engine 10 is stopped. Thereby, the regeneration of the filter 23 is interrupted.

Therefore, in the second embodiment, substantially the same effects as in the first embodiment can be exerted. Further, in the second embodiment, when the ignition switch 36 is turned off, the engine time is not determined by the temperature of the electric heater 24 but by the elapsed time from the start of the regeneration of the filter 23 as in the first embodiment. Decide whether to stop 10 or not. That is, since the temperature of the electric heater 24 is directly detected to determine whether to stop the engine 10, more accurate control can be performed.

The embodiment of the present invention may be modified as follows. In the above embodiment, the present invention is embodied in a vehicle having one muffler, but may be embodied in a vehicle having a plurality of mufflers. When the vehicle is provided with a plurality of mufflers, each muffler is provided with a switching valve capable of switching the flow of exhaust gas by the control circuit 30. Then, when the engine 10 is restarted immediately after the regeneration of the filter 23 is interrupted, the valve corresponding to the filter 23 whose regeneration has been interrupted is closed to prevent exhaust gas from entering the casing 21 in which the filter 23 is accommodated. To Thereby, it is possible to prevent the filter 23 from being damaged by heat.

When the regeneration of the filter 23 is interrupted, the engine speed or the engine drive signal may be input to the control circuit 30 provided in the exhaust gas purification device 20. According to this configuration, the operation check of the engine 10 becomes clear, and the regeneration interruption processing of the filter 23 can be reliably performed.

As a means for heating the filter 23, for example, a burner or a spark plug may be used in addition to the electric heater 24. In the above embodiment, the drive of the engine 10 was controlled by controlling the on / off of the relay 37. In addition, on / off of the engine 10 may be controlled by an engine control circuit that controls the engine 10. Specifically, the ignition switch 36
Is turned off, and if 15 minutes or more have elapsed since the regeneration of the filter 23 was started, the control circuit 30 outputs a signal to the engine control circuit to continue driving the engine 10. . If it is less than 15 minutes,
The control circuit 30 controls the engine 10
And outputs a signal for stopping the drive.

When the filter 23 is regenerated in an idling state of the engine 10 because the electric heater 24 consumes a large amount of power, the engine control circuit may increase the rotation speed of the engine 10.

In the second embodiment, the electric heater 24
Is detected, a filter temperature detection sensor 28 for detecting the temperature of the filter 23 may be provided as shown by a two-dot chain line in FIG. According to this configuration, when the engine is stopped during regeneration of the filter 23 and the engine 10 is started immediately thereafter, the filter 23 is stopped.
If the temperature has already reached the predetermined temperature (550 ° C.) or more, the engine 10 can be stopped. Therefore,
Prevents particulates from causing excessive combustion,
The filter 23 can be reliably prevented from being thermally damaged.

Next, in addition to the technical ideas described in the claims, technical ideas grasped by the above-described embodiment will be listed below. (1) The exhaust gas purifying apparatus according to claim 2, further comprising a filter temperature sensor for measuring a temperature of the filter, wherein the predetermined condition is that a temperature detected by the filter temperature sensor reaches a predetermined temperature. And the control means turns off the heating means based on this condition. With this configuration, it is possible to prevent the filter from being damaged by heat.

[0054]

As described in detail above, according to the present invention,
Even if the operation of stopping the engine is performed during the regeneration of the filter, the heating of the filter by the heating means can be continued. Therefore, the substance accumulated in the filter can be completely burned, and the filter can be efficiently regenerated.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view of an exhaust gas purification device according to a first embodiment.

FIG. 2 is a flowchart showing the operation.

FIG. 3 is a schematic explanatory view of an exhaust gas purification device according to a second embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Engine (internal combustion engine), 20 ... Exhaust gas purification apparatus, 21 ... Casing, 23 ... Filter, 24 ... Electric heater (heating means), 30 ... Control circuit (Control means, timer, storage means), 37 ... Relay ( Stop means)

Continued on the front page F term (reference) 3G090 AA02 BA04 CA01 CA02 CA04 CB12 CB13 DA04 DA11 DA13 DB01 DB02 DB03 DB04 DB05 DB07 3G092 AA02 CA01 EA17 FA18 HD08Z HF20Z 4D058 MA42 MA54 SA06

Claims (7)

[Claims] 1. A casing provided on an exhaust flow passage of an internal combustion engine, a filter housed in the casing and collecting particulates contained in exhaust gas discharged from the internal combustion engine, A heating means disposed on the upstream side for burning the particulates deposited on the filter, wherein the heating means heats the filter to burn the particulates, thereby regenerating the filter. In the above, a control means for turning on and off the heating means is provided, and the control means continues heating by the heating means for a predetermined time even when the internal combustion engine is stopped during regeneration of the filter. Exhaust gas purifying device. 2. The exhaust gas purification system according to claim 1, wherein the control unit does not continue heating the filter by the heating unit if a predetermined condition is satisfied after the internal combustion engine is stopped. apparatus. 3. A timer for measuring an elapsed time after the heating means is turned on, and if the elapsed time measured by the timer has not reached a predetermined time, the control means turns off the heating means. The exhaust gas purifying apparatus according to claim 2, wherein: 4. A temperature sensor for measuring the temperature of the heating means, and if the temperature detected by the temperature sensor has not reached a predetermined temperature, the control means turns off the heating means. The exhaust gas purification device according to claim 2, wherein 5. An exhaust gas purifying apparatus according to claim 1, further comprising a stopping means for forcibly stopping said internal combustion engine. 6. A storage means for storing an elapsed time from when the heating means is turned on, wherein the control is performed when the internal combustion engine is restarted after the internal combustion engine is stopped during regeneration of the filter. The means calculates a regeneration time required to regenerate the filter based on the elapsed time stored in the storage means, and turns on the heating means for the calculated regeneration time. An exhaust gas purifying apparatus according to any one of claims 5 to 10. 7. A casing provided on an exhaust passage of an internal combustion engine, a filter housed in the casing and collecting particulates contained in exhaust gas discharged from the internal combustion engine, Heating means disposed on the upstream side for burning particulates deposited on the filter, wherein the heating means heats the filter to burn the particulates, thereby regenerating the filter. In the gas purification method, even when the internal combustion engine is stopped during regeneration of the filter,
An exhaust gas purifying method characterized in that the filter is heated by the heating means while the internal combustion engine is continuously driven if a predetermined condition is satisfied.