JPH08284641A - Exhaust emission control system for engine with supercharger - Google Patents

Abstract

PURPOSE: To supply oxygen to a regenerating filter unit utilizing a supercharger without being influenced by the operating period of the supercharger. CONSTITUTION: An exhaust emission control device 1 is connected to the exhaust passage of a diesel engine 2 in which a turbo charger 4 is arranged. A reserving tank 7 is connected to a surge tank 5 connected to the turbo charger 4 through a first pipe passage 6, and a check valve 8 is arranged on the first pipe passage 6 to open the check valve 8 when pressure in the surge tank 5 exceeds prescribed pressure or more. A plurality of filter units provided with a heater are mounted in parallel with each other in the device 1, and a valve is arranged in the device 1 to close an opening for leading exhaust gas in each filter unit at the time of regenerating period of the filter unit. The second end part of a second pipe passage 33 whose first end part is connected to the reserving tank 7 is connected to a passage for communicating the filter unit and a housing with each other when a valve is arranged on a position for closing the opening of the filter unit. An electromagnetic switching valve 34 is arranged in the second pipe passage 33.

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 for an engine with a supercharger, and more specifically, it is equipped with a plurality of filter units in parallel, and deposits collected by the filter units are operated by an engine with a supercharger. The present invention relates to an exhaust gas purification device in which the filtering function of a filter unit can be regenerated by burning and removing it inside.

[0002]

2. Description of the Related Art Various exhaust gas purifying devices (filter devices) for removing particulates (mixture of carbon fine particles, engine oil, and unburned fuel) contained in the exhaust gas of diesel engines have been conventionally proposed. . The exhaust gas purifying apparatus is used by being connected to an exhaust pipe of an engine, and when particulates are accumulated to a certain extent due to use, the back pressure of the exhaust pipe increases due to the accumulated particulates, and the output of the engine decreases. In order to prevent this, it is necessary to remove the accumulated particulates and regenerate the filtration function before the accumulation of particulates proceeds until the output of the engine decreases.

In the case of an exhaust gas purifying apparatus for a diesel engine equipped in an automobile or the like, it is practically preferable that the filter can be regenerated while the engine is operating. As such an exhaust gas purifying device, an exhaust gas purifying device is disclosed in which particulates accumulated in a trap (filter) are burned by a burner to regenerate the filter (for example,
JP-A-56-115809, JP-A-59-212
No. 710). As for the amount of oxygen required for burning particulates, the surplus oxygen in the exhaust gas is sufficient under normal operating conditions. However, when the engine is operated at a high load such as when climbing a slope, the amount of excess oxygen becomes small and the oxygen required for burning particulates becomes insufficient, so it is necessary to introduce air into the burner. Japanese Patent Laid-Open No. 56-115809 has an air pump driven by an engine and introduces air from the air pump into the burner. for that reason,
There is a problem that the trap regenerator becomes large-scaled, and the air pump is driven even in a low load region where it is not necessary to introduce air, and an unnecessary load is applied to the engine to deteriorate fuel efficiency.

Japanese Laid-Open Patent Publication No. 59-2111710 discloses a regenerator which introduces air into a burner by using a supercharger mounted on an engine without providing an air pump. As shown in FIG. 5, in this device, a trap (filter) 55 is connected to an exhaust outlet of a turbine 53 of a supercharger 52 mounted on a diesel engine 51 via an exhaust passage 54. A burner 56 is installed upstream of the trap 55, and the compressor 5 of the supercharger 52 is installed in the burner 56.
A secondary air supply passage 60 branched from a supercharging duct 59 from the outlet of 7 to the collecting portion of the intake manifold 58 is connected. A fuel injection valve 61 is arranged near the downstream end of the secondary air supply passage 60, and a secondary air control passage 63 is provided from the secondary air supply passage 60 upstream of the fuel injection valve 61 via a secondary air control valve 62. It is branched and the compressor 57
Is connected to an intake duct 64 communicating with the inlet of the.

In the burner 56, in the operating region of the supercharger 52, when the back pressure upstream of the trap 55 is a predetermined value or more,
5 Operates only when the exhaust gas temperature at the inlet is below a predetermined value.
When the burner 56 operates, the secondary air control valve 62 opens, and the pressurized air taken out from the supercharging duct 59 allows the fuel injection valve 6 to operate.
It is introduced into the burner 56 through the secondary air supply passage 60 together with the fuel injected from the No. 1. Then, the contact with the heated glow plug 65 ignites and burns, and the combustion heat removes the particulates trapped in the trap 55.

As an exhaust gas purifying apparatus which can be regenerated while the engine is operating, an exhaust gas purifying apparatus provided with a large number of filter units incorporating an electric heater for removing particulates has been proposed (for example, USP5.
No. 293742, Tokuhyo 6-501295, etc.).
In these devices, it is possible to regenerate the filter units even when the engine is in operation by shifting the energization times to the plurality of filter units and sequentially regenerating them.

It is generally 6 to burn particulates.
It is necessary to raise the temperature to 00 ° C or higher. The flow rate of the exhaust gas flowing through the filter unit while the engine is operating varies depending on the structure of the filter device, the displacement of the engine, and the number of revolutions, but it is considerable. In the heater heating method, when the filter unit is regenerated with the exhaust gas flowing into the filter unit, the heat generated by the heater is carried away by the exhaust gas flow passing through the filter unit. As a result, the heat generated by the heater is not effectively used for burning the particulates, and the power consumption increases.

In order to solve this inconvenience, in the above-mentioned conventional device using a heater, when the filter unit is regenerated,
The particulates are burnt while the inflow of exhaust gas into the filter unit is temporarily blocked. In this case, at the time of regenerating the filter unit, after closing the opening of the filter unit with a valve to block the inflow of exhaust gas, the heater is energized to heat the heater for a predetermined time required for burning particulates.

However, when the inflow of exhaust gas into the filter unit to be regenerated is cut off, the amount of oxygen required for the combustion of particulates is insufficient, and the combustion of the accumulated particulates becomes incomplete, resulting in insufficient regeneration of the filtration function. May be In order to eliminate this inconvenience, the special table 6-501
Japanese Laid-Open Patent Publication No. 295 discloses an exhaust gas purifying apparatus capable of restricting the flow of exhaust gas into the filter unit to be regenerated when the filter unit is regenerated and supplying oxygen.

In this exhaust gas purifying apparatus, a plurality of filter units are arranged in parallel in a housing. A heater is arranged on the downstream side in each filter unit,
Poppet valves each having a valve body that opens and closes the opening are disposed at positions facing the opening of the filter unit. A passage is formed in the valve body and a piston rod that supports the valve body, and the piston rod disposes the valve body in the closed position when compressed air is supplied from the oxygen supply source through the line and the valve. Compressed air is supplied to the filter unit.

[0011]

[Problems to be Solved by the Invention] Japanese Patent Application Laid-Open No. 56-1158
In the exhaust gas purifying apparatus disclosed in Japanese Patent Application Laid-Open No. 09-212710 and Japanese Patent Laid-Open No. 59-2111710, the amount of particulates to be burned at the time of regeneration is large, and therefore, compared with an exhaust gas purifying apparatus that sequentially regenerates a plurality of filter units. There is a problem in terms of durability because the temperature of the housing becomes higher.

Therefore, it is preferable to use an exhaust gas purifying apparatus of a type in which a plurality of filter units are arranged in parallel and one filter unit or all filter units are divided into a plurality of groups and each group is sequentially regenerated. Japanese Patent Publication No. 6-501295 discloses that oxygen is supplied from an oxygen supply source to each filter unit in which introduction of exhaust gas is restricted during regeneration.
Although no specific configuration is disclosed as an oxygen supply source,
An air pump or compressor driven by an engine can be considered. However, when an air pump or a compressor is used as an oxygen supply source, there is a problem that the regeneration device becomes large-scale as described above, and the engine is always driven to waste a load to deteriorate fuel efficiency. is there.

When a plurality of filter units are arranged in parallel and oxygen is supplied to each filter unit of an exhaust gas purifying system of a type in which one filter unit or all filter units are divided into a plurality of sets and each group is sequentially regenerated It is possible to apply the device disclosed in Japanese Patent Laid-Open No. 59-2111710 as an oxygen supply source. That is, the air supply passage is branched from the supercharging duct of the engine equipped with the supercharger to communicate with each filter unit, and the passage branched from the middle of the air supply passage via the control valve is connected to the compressor of the supercharger. Connect to the intake duct that communicates with the inlet. According to this configuration, it is possible to supply oxygen to each filter unit by using the supercharger installed in the engine without installing an air pump or compressor for oxygen supply, and when installing an air pump or the like. The problem of is solved.

In the device disclosed in Japanese Unexamined Patent Publication No. 59-2111710, the filter device is regenerated when the load is high, so the supercharger is always operating during regeneration, and a part of the air in the supercharger is removed. Even if it is used, it does not hinder the operation of the engine. However, the time when the filter is regenerated by the exhaust gas purifying apparatus including the plurality of filter units is not always at the time of high load, and the supercharger is not always operating at the time of regeneration. Simply providing a passage for supplying the air of the supercharger to the filter unit cannot reliably supply oxygen during the regeneration period.

The present invention has been made in view of the above problems, and an object thereof is to provide an exhaust gas purifying apparatus equipped with a plurality of filter units in parallel, without excessive influence of the operation timing of the supercharger. An object of the present invention is to provide an exhaust gas purifying apparatus for an engine with a supercharger, which is capable of supplying oxygen to a filter unit being regenerated by using a feeder.

[0016]

In order to achieve the above-mentioned object, in the invention according to claim 1, it is used by being connected to an exhaust passage of an engine with a supercharger, and a plurality of filter units are provided in a housing. In an exhaust gas purifying apparatus equipped in parallel, a reserve tank connected to a supercharging duct of the engine via a first pipeline, and a reverse tank provided in the first pipeline and opening at a supercharging pressure above a set pressure. A stop valve; a passage for communicating the filter unit with the outside of the housing; a second conduit for communicating the reserve tank with the passage; a valve provided in the second conduit; And a control means for controlling the operation of the valve during regeneration.

According to a second aspect of the present invention, the exhaust gas purifying apparatus is provided with an electric heating means in each of the filter units, and controls the introduction of exhaust gas into each filter unit when the filter unit is regenerated. When the introduction of exhaust gas is regulated by at least each filter unit by the exhaust gas introduction regulation means, the passage communicates the filter unit with the outside of the housing, and the control means controls the exhaust gas introduction at the time of regeneration of the filter unit. And controlling the means and the electrical heating means.

According to a third aspect of the invention, in the invention according to the second aspect, at least a part of the passage is formed in the exhaust gas introduction regulation means, and the exhaust gas introduction is regulated by the exhaust gas introduction regulation means. It is opened at a position corresponding to the opening.

According to a fourth aspect of the present invention, in the second or third aspect of the invention, the filter unit includes a tubular filter portion made of heat-resistant fiber and closed at one end, and the exhaust gas introduction regulation is provided. The means includes a valve movably provided in a closed position for closing an exhaust gas introduction opening of each filter unit and an open position for opening the opening, and the valve is opened and closed for a predetermined filter unit. Drive means for moving to and from the position.

According to a fifth aspect of the invention, in the invention according to any one of the first to fourth aspects, the second
At least a part of the pipeline is arranged in the exhaust passage of the engine.

According to a sixth aspect of the invention, in the invention according to any one of the first to fourth aspects, the second
A throttle valve is provided in the pipeline.

[0022]

According to the present invention, the particulates in the exhaust gas of the engine with the supercharger are collected while the exhaust gas of the engine with the supercharger passes through the plurality of filter units. When the supercharging pressure exceeds the set pressure while the engine is operating, the check valve opens and pressurized air is supplied and stored in the reserve tank. When the filter unit is regenerated, the valve is operated and controlled by the control means, and the pressurized air in the reserve tank is supplied into the filter unit through the second pipeline and the passage. Then, the particulates deposited on the filter unit are burned and removed in the presence of sufficient oxygen.

According to the second aspect of the present invention, when the filter unit is regenerated, the control means controls the operation of the exhaust gas introduction restricting means and the valve to restrict the introduction of the exhaust gas into the predetermined filter unit, and the reserve tank. The pressurized air therein is supplied into the filter unit through the second pipeline and the passage. Then, the electrical heating means is energized to burn off the particulates deposited on the filter unit.

According to the invention of claim 3, in the invention of claim 2, the opening of the passage is arranged at a position corresponding to the opening of the filter unit whose exhaust gas introduction is restricted by the exhaust gas introduction restricting means. . Then, the air in the reserve tank can be supplied to the filter unit in which the introduction of exhaust gas is restricted.

In the invention according to claim 4, in the invention according to claim 2 or 3, the particulates are collected in a tubular filter portion made of a heat resistant fiber and closed at one end. When the filter unit is regenerated, the opening for introducing the exhaust gas of the filter unit to be regenerated is closed by the valve driven by the drive means.

According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the air supplied from the reserve tank to the filter unit via the second pipeline is the second one. The conduit is heated while passing through the location in the exhaust passage of the engine. Then, since the heated air is supplied to the filter unit, the amount of heat required to heat the supplied air to the combustion temperature of the particulates decreases. When heating with the electric heating means, the power consumption of the electric heating means is reduced.

According to a sixth aspect of the present invention, in the invention according to any one of the first to fifth aspects, the pressure in the reserve tank is increased by the action of the throttle valve provided in the second pipeline. Regardless, the air in the reserve tank is supplied to the filter unit by a predetermined amount.

[0028]

【Example】

(Embodiment 1) A first embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 1, the exhaust gas purification device 1 is connected to an exhaust passage 3 of a diesel engine 2. The diesel engine 2 has a turbocharger 4 as a supercharger. The surge tank 5 as a supercharging duct connected to the turbocharger 4 has a first
The first end of the pipe 6 is connected, and the second end thereof is connected to the reserve tank 7. The first pipe 6 is provided with a check valve 8 that opens when the supercharging pressure, that is, the pressure in the surge tank 5 is equal to or higher than the set pressure.

As shown in FIGS. 2 and 3, in the exhaust gas purifying apparatus 1, the disk-shaped partition plate 10 is disposed in front of the cylindrical housing 9 (on the right side in FIG. 3) and is orthogonal to the longitudinal direction of the housing 9. It is fixedly placed in. The partition plate 10 partitions the inside of the housing 9 into an exhaust gas introduction side space 11 and an exhaust side space 12. An exhaust gas introduction pipe 13 communicating with the exhaust gas introduction side space 11 is projectingly provided on the front wall 9a of the housing 9, and an exhaust pipe 14 communicating with the discharge side space 12 is provided on the rear wall 9b.
Is protruding. The exhaust gas purification device 1 also constitutes a part of the exhaust passage of the diesel engine 2. A plurality of (four in this embodiment) filter units 1 are provided in the housing 9.
5 are arranged in parallel.

The filter unit 15 comprises a cylindrical filter 16 formed in a cylindrical shape, and a heater 17 arranged along the inner surface of the cylindrical filter 16 as an electric heating means. As the cylindrical filter 16, for example, the cylindrical filter previously proposed by the applicant of the present application in JP-A-6-264722 and the like is used. This tubular filter is constructed in a sandwich shape in which a nonwoven fabric made of heat-resistant short fibers is arranged between cylindrical woven fabrics made of heat-resistant fibers. That is, the filter unit 15 includes a tubular filter portion made of heat resistant fiber and having one end closed. The heater 17 is formed in a spiral shape having a diameter slightly smaller than the inner diameter of the tubular filter 16.

The filter unit 1 is provided on the front surface of the partition plate 10.
5, a fan-shaped recess 10 forming an opening for introducing exhaust gas into
a is formed by the number of the filter units 15, and a mounting hole 1 for mounting the filter units 15 on the bottom thereof.
0b is formed. A tubular fixing member 18 forming an opening 15a is fitted and fixed to the first end of the cylindrical filter 16, and a closing member 19 is fitted to the second end.
The fixing bracket 18 of the filter unit 15 has a mounting hole 10b.
It is fixed to the partition plate 10 in a state of being fitted and fixed to.

A through hole is formed in the fixing member 18 and the closing member 19, and the end of the heater 17 is connected to the electric wire 22 by a screw 20 inserted into the through hole and a nut 21 screwed to the screw 20. Fixing member 18 and closing member 1 in the closed state
It is fixed at 9. The screw 20 is an insulator 23a,
The fixing metal fitting 18 and the closing member 19 are inserted into the through hole via 23b, and the electric current cannot be supplied to the fixing metal fitting 18 and the closing member 19. As shown in FIG. 1, the electric wire 22 is drawn out of the housing 9 and connected to the battery 25 via a heater relay 24.
The heater relay 24 is a controller 26 as a control means.
Is controlled to open and close, and when the heater relay 24 is closed, the corresponding heater 17 is energized.

As shown in FIGS. 2 and 3, the housing 9
A rotation shaft 27 is disposed in the center of the housing 9 along the longitudinal direction of the housing 9 while penetrating the front wall 9a and having its first end rotatably supported by the partition plate 10. . A valve 28 is provided on the first end side of the rotary shaft 27, and a driven gear 29 is integrally rotatably fixed on the second end thereof. The valve 28 is formed in a fan shape capable of closing one recess 10 a, and is provided in a state of slidingly contacting the front surface of the partition plate 10. Further, the valve 28 is arranged at a position where it always closes one recess 10a and shuts off the introduction of exhaust gas into the filter unit 15. A motor 30 is arranged on the outer surface of the front wall 9a, and a drive gear 31 meshing with a driven gear 29 is fixed to an output shaft 30a of the motor 30 so as to be integrally rotatable. The ratio of the numbers of teeth of both gears 29 and 31 is 4/1, and when the output shaft 30a makes one rotation, the driven gear 29
Is rotated by 90 ° to open the recess 10a that has been closed until then, and is arranged at a position to close the adjacent recess 10a. Motor 30 and both gears 29, 31
Constitutes a drive means, and the drive means and the valve 28 constitute an exhaust gas introduction regulation means.

As shown in FIGS. 2 and 3, the partition plate 10 has a first passage 32a extending in the radial direction and a first passage 32a.
And a second passage 32b formed so as to surround the rotation shaft 27 and communicate with the second passage 32b. The valve 28 has a first end communicating with the second passage 32b, and a second end formed with a third passage 32c opening to a position corresponding to the recess 10a when the valve 28 is placed in the closed position. There is. The first to third
The passages 32a, 32b, 32c constitute passages for connecting the filter unit 15 and the outside of the housing 9 when the introduction of the exhaust gas into each filter unit 15 is restricted by the exhaust gas introduction restricting means.

As shown in FIGS. 1 and 3, the second pipe line 33 having the first end connected to the reserve tank 7 has the second end connected to the first passage 32a of the exhaust gas purifying apparatus 1. There is. An electromagnetic switching valve 34 as a valve is provided in the second pipeline 33, and an orifice 35 as a throttle valve is provided downstream of the electromagnetic switching valve 34 (on the side of the exhaust gas purifying device). The electromagnetic switching valve 34 can be switched between two positions, an air supply position that opens the second conduit 33 and a closed position that closes the second conduit 33, in response to a signal from the controller 26. A pressure sensor 36 for detecting the pressure of the introduced exhaust gas is attached to the inlet side of the exhaust gas purification device 1, and the pressure sensor 36 is electrically connected to the controller 26. The controller 26 determines the regeneration timing of the filter unit 15 based on the detection signal from the pressure sensor 36 and controls the energization of the heater 17, the operation of the motor 30, and the switching operation of the electromagnetic switching valve 34. It has become.

The controller 26 switches the electromagnetic switching valve 34 to the air supply position at the time when the time for the filter unit 1 to reach the particulate ignition temperature elapses after the heater 17 is energized when the filter unit 1 is regenerated. It is like this.

Next, the operation of the exhaust gas purifying apparatus 1 configured as described above will be described. The exhaust gas introduced from the exhaust gas introduction pipe 13 into the exhaust gas introduction side space 11 is guided to the inside of each filter unit 15 through the recess 10a and the opening 15a, and passes through the tubular filter 16 from the inside to the outside. Then, while passing through the tubular filter 16, particulates and the like contained in the exhaust gas are filtered, and the cleaned exhaust gas is discharged from the exhaust pipe 14 through the discharge side space 12.

The valve 28 is arranged at a position for closing any one of the recesses 10a, and the exhaust gas is processed by the three filter units 15. The pressure (back pressure) in the exhaust gas introduction pipe 13 rises as the amount of particulates collected by the tubular filter 16 increases. Then, the filter unit 15 is regenerated after the back pressure reaches the regeneration start set pressure.

During operation of the diesel engine 2, when the pressure in the surge tank 5 reaches or exceeds a predetermined set pressure at a high speed or the like, the check valve 8 is opened and the pressurized air is supplied to the first pipe line 6.
And then sent from the surge tank 5 into the reserve tank 7. That is, when the supercharging pressure has a margin, pressurized air is supplied from the surge tank 5 into the reserve tank 7 and is stored in the reserve tank 7.

At the reproduction time, an operation command is output from the controller 26 to the motor 30, and the motor 30 is operated only by rotating the rotating shaft 27 by ¼ rotation. As a result, the valve 28 is also rotated 1/4 turn, and the recess 10a corresponding to the filter unit 15 adjacent to the filter unit 15 which was held in the closed state until then is closed by the valve 28, and the filter unit 15 is closed. The introduction of exhaust gas is cut off. At this time, the second end of the third passage 32c is in a state corresponding to the opening 15a of the filter unit 15. Next, the heater 17 of the filter unit 15 is energized and heated via the heater relay 24 for a predetermined time.
After the start of energization of the heater 17, and after a lapse of a predetermined time necessary for the temperature of the particulates to reach the ignition temperature, the electromagnetic switching valve 34 is switched to the air supply position by a command from the controller 26. Then, oxygen (air) is supplied from the reserve tank 7 to the filter unit 15 through the second pipe 33, the electromagnetic switching valve 34, the orifice 35, the first passage 32a, the second passage 32b and the third passage 32c.

Orifice 35 provided in the second conduit 33
By the action of, the air in the reserve tank 7 is being regenerated regardless of the pressure in the reserve tank 7.
5 is supplied by a predetermined amount. The particulates are burned in the presence of sufficient oxygen while the particulates are heated to the combustion temperature or higher by the heat generated by the heater 17. The particulates deposited on the tubular filter 16 are first burned by the heat generated by the heater 17 and deposited on the inside of the tubular filter 16 near the heater 17. Thereafter, the heat generated by the heater 17 and the heat generated by the combustion of particulates are sequentially burned toward the outside of the cylindrical filter 16 to regenerate the filter unit 15.

After the energization and the air supply to the heater 17 are continued for a predetermined time and the combustion of the particulates is completed, the energization to the heater 17 is stopped and the electromagnetic switching valve 34 is switched to the closed position. Supply is stopped. The valve 28 is arranged in the closed position corresponding to the regenerated filter unit 15 until the next regeneration time, and the filter unit 15 is held in the rest state. Then, each time the back pressure reaches the predetermined set pressure again, the filter units 8 are regenerated one by one in the same manner as described above.

The turbocharger 4 does not always operate when the filter unit is regenerated. However, when the filter units 15 are regenerated, not all of the filter units 15 are regenerated at the same time, but one by one. Moreover, unlike the case of using the burner, the fuel is heated by the heater without burning, so that the amount of oxygen required for regeneration may be small. Therefore, with the pressurized air stored in the reserve tank 7 when the supercharging pressure has a margin,
The amount of oxygen required for the regeneration of each filter unit 15 can be sufficiently covered. That is, by utilizing a part of the supercharged air from the turbocharger 4 equipped in the diesel engine 2, an air pump or a compressor for supplying oxygen during filter regeneration, and a transmission mechanism for transmitting power from the diesel engine. Is unnecessary, the structure is simple and the cost is low. In addition, the energy for driving the air pump and the like is unnecessary, and the fuel efficiency is improved.

In this embodiment, since the particulate filter 16 made of heat-resistant fiber collects the particulates, the amount of particulates deposited on each filter unit 15 at the time of regeneration is the same as that of the honeycomb ceramic filter. It is slightly smaller than when used. Therefore, since the amount of oxygen required for regeneration may be smaller, the required minimum amount of pressurized air stored in the reserve tank 7 can be reduced, and the volume of the reserve tank 7 can be reduced.

The combustion of particulates requires a high temperature of 600 ° C. or higher, and the temperature of oxygen supplied is much lower than that. Therefore, if the air supply to the filter unit 15 is started at the same time when the heater 17 is energized, the supplied air removes the heat of the filter unit 15 and moves to the discharge side space 12. Therefore, the heater 1
Extra heating by 7 is required, and power consumption increases. However, in this embodiment, since the supply of air is started after the particulates have been heated to the ignition temperature, the amount of heat for heating the filter unit 15 to the predetermined temperature is small, and the supplied air has the particulates. It surely plays a role of supporting combustion.

One valve 28 that rotates integrally with the rotating shaft 27
When the flow of exhaust gas into the filter unit 15 is blocked by, the third passage 32c enters a state corresponding to the filter unit 15. That is, it becomes possible to supply the air in the reserve tank 7 only to the filter unit 15 in which the introduction of the exhaust gas is restricted, and it is possible to avoid the trouble of supplying the air to another filter unit by mistake. Further, in this embodiment, regardless of the number of filter units 15, only one passage communicates with the second pipeline 33 communicating with the reserve tank 7, and there is no need to branch the second pipeline 33. The configuration for supplying air to the filter unit 15 becomes simple.

Further, in this embodiment, any one of the filter units 15 is held in a state in which the inflow of exhaust gas is blocked, that is, in a rest state, and during the rest state of the filter unit 15, regeneration processing of the filter unit 15 is performed. Is done. Then, when the filter unit 15 is regenerated,
Since the regenerated filter unit 15 which has been in a rest state without performing the exhaust gas treatment until then is opened and the exhaust gas treatment is performed instead of the filter unit 15 to be regenerated, there is no inconvenience that the back pressure suddenly rises during regeneration.

(Second Embodiment) Next, a second embodiment will be described with reference to FIG.
A description will be given according to (a) and (b). This embodiment is different from the above embodiment in that the air supplied to the filter unit 15 is preheated when the filter unit 15 is regenerated.
Other configurations are the same. The same parts are designated by the same reference numerals and detailed description thereof will be omitted.

A part of the second conduit 33 is arranged in the exhaust passage 3, and the first conduit 33 extends from the exhaust passage 3 through the exhaust gas introducing pipe 13.
It is connected to the conduit 32a. The second pipe line 33 has a coil-shaped portion provided in the exhaust passage 3, the exhaust gas introduction portion 13, and the exhaust gas introduction side space 11. First passage 3
2a is closed on the side opposite to the side communicating with the second passage 32b.

In this embodiment, from the reserve tank 7 to the second
The air supplied to the filter unit 15 via the conduit 33, the electromagnetic switching valve 34, and the orifice 35 is the second conduit 33.
Is heated by heat exchange with the exhaust gas while passing through the exhaust passage 3, the exhaust gas introducing portion 13, and the location provided in the exhaust gas introducing side space 11. Then, since the heated air is supplied to the filter unit 15, the heated heater and the particulates are prevented from being cooled, and the power consumption of the heater 17 is reduced. Moreover, since the portion disposed in the exhaust passage 3 or the like is formed in a coil shape, the efficiency of heat exchange is improved.

The present invention is not limited to the above-mentioned embodiments, but may be embodied as follows. (1) In the second embodiment, instead of connecting the second pipe line 33 from the exhaust gas introduction pipe 13 side to the first passage 32a, the second pipe line 33 is arranged in the exhaust pipe 14 and the discharge side space 12, and the second end portion thereof is provided. May be connected to the first passage 32a, but immediately before the regeneration, the time has elapsed from the previous regeneration, and it is preferable to be on the side of the exhaust gas introduction pipe 13 where the temperature is higher.

(2) Instead of the orifice 35, a variable throttle valve may be provided or the orifice 35 may be omitted. (3) The present invention may be applied to an exhaust gas purification apparatus for a diesel engine equipped with a turbocharger other than the turbocharger 4, or an exhaust gas purification apparatus for a gasoline engine equipped with a turbocharger, not limited to the diesel engine.

(4) In both of the above-mentioned embodiments, the supply of oxygen is not necessarily started after the temperature of the filter unit reaches the ignition temperature of the particulates, but the heater 17 is used.
It may be performed at the same time as the start of energization or after a predetermined time has elapsed from the start of energization.

(5) The rotary shaft 27 and the valve 28 are formed with a passage which is connected to the second conduit 33 and supplies air from the reserve tank 7 to the filter unit 15. For example, a pipe is used as the rotating shaft, a blocking member is fitted to the first end of the pipe, and the second conduit 33 is connected to the second end of the pipe so as to be relatively rotatable. Then, the valve 28 is fitted and fixed to the rotary shaft 27 so that the first end portion communicates with the inside of the pipe and the valve 28
Forms a passage in the valve 28 and the pivot shaft 27 whose second end opens at a position corresponding to the inside of the filter unit 15 of the valve 28 when the valve is placed in the closed position. In this case, the passage can be easily processed.

(6) As many branch pipes as the number of filter units 15 are provided in the second pipeline 33, and electromagnetic switching valves 34 are provided in each branch pipeline, and each branch pipeline is filtered by the closing member 19 of each filter unit. It is connected to a passage formed so as to communicate with the inside of the unit 15. A check valve is provided downstream of the electromagnetic switching valve 34 in each branch line.

(7) One valve 2 as an exhaust gas introduction regulation means for regulating the introduction of exhaust gas into the filter unit 15.
Instead of the structure in which 8 is rotated, a valve that is moved to a closed position and an open position by an actuator may be provided for each filter unit 15. In this case, the adoption of the configuration (6) as the air supply means makes the configuration relatively simple.

(8) The filter unit 15 is not limited to the cylindrical shape, but may be formed in a rectangular tube shape or a flat cylindrical shape. Also,
The filter is not limited to a sandwich structure of a cylindrical woven fabric and a non-woven fabric, but a general flat woven fabric formed into a tubular shape or a laminate thereof, or a ceramic fiber wound around the outer peripheral surface of the breathable support material in layers. It may be one. Furthermore,
Ceramic filters may be used.

(9) The heater 17 is connected to the filter unit 1
No. 5, which is arranged on the opening side, or JP-A-2-256.
As described in Japanese Patent No. 812, a configuration may be adopted in which a ceramic fiber and a heater are wound in a plurality of layers on the outer peripheral surface of a breathable support material.

(10) A cylindrical partition may be provided outside each filter unit 15 so that the exhaust gas passing through the filter unit 15 is guided to the outlet without contacting the filter unit 15 being regenerated. . Further, in the case of a configuration in which a cylindrical partition wall is arranged outside each filter unit 15, the exhaust gas may be used in a state where the exhaust gas flows from the outside to the inside of the cylindrical filter 16. In this case, exhaust pipe 1
4 is the exhaust gas introduction side, the exhaust gas introduction pipe 13 is the discharge side, and the means for restricting the introduction of the exhaust gas into the filter unit 15 is configured to close the end of the cylindrical partition wall with a valve.

(11) The diameter of the filter unit 15 is reduced so that a plurality of filter units 15 can be simultaneously closed by one valve 28 having the same area. In this case, since the effective filtration area of the filter unit 15 arranged in the region that can be closed at once by the valve 28 increases, the valve 2
Although the configuration for driving 8 is the same, the intervals between the regeneration times of the filter unit 15 can be lengthened even in the exhaust gas purification device 1 having the same volume.

(12) As the exhaust gas purifying device 1 such as the device disclosed in Japanese Patent Publication No. 6-501295, a ceramic filter is provided as a filter unit, and the exhaust gas is introduced into the filter unit as a structure. You may use what provided the valve in the position which closes the opening by the side of the outlet of each filter unit.

(13) Heater 1 as electric heating means
Instead of 7, a means for generating an alternating magnetic field, for example, a coil may be wound around the outside of the filter unit 15. (14) A configuration may be adopted in which regeneration is performed in a state in which exhaust gas is introduced into the filter unit 15 without providing the valve 28 that restricts introduction of exhaust gas into the filter unit 15 during regeneration. In this case, it is preferable to use a burner instead of the heater 17.

(15) As the filter unit, a filter unit in which a catalyst is supported on the filtration surface is used.
It may be applied to a filter device that lowers the combustion temperature.
In this case, the combustion temperature is reached only by raising the temperature of the exhaust gas, and it is possible to omit the heating means such as the heater 17 and the burner.

Inventions other than those described in the claims that can be grasped from the embodiments and the modifications will be described below together with their effects. (1) In the inventions of claims 2 to 4, the supply of oxygen is started after the temperature of the filter unit reaches the ignition temperature of the particulates by energizing the electric heating means. In this case, the supplied oxygen is effectively used for burning particulates, and the power consumption required for regeneration is reduced.

(2) In the invention described in claim 4,
The valve is integrally rotatably provided on a rotary shaft, and the drive means has a closed position for selectively closing the opening for introducing exhaust gas of a predetermined filter unit and an open position for opening the opening. The rotation shaft is driven so as to rotate to. In this case, the opening portion of each filter unit can be opened and closed by one driving means, and the configuration is simplified.

[0066]

As described in detail above, the first to sixth aspects of the invention are described.
According to the invention described in (1), oxygen can be supplied to the filter unit being regenerated by using the supercharger without being affected by the operation timing of the supercharger. Therefore, as compared with the case where an air pump or the like is provided for supplying oxygen, the system for supplying oxygen becomes simpler, the system can be made smaller and lighter, and the manufacturing cost can be reduced. Further, driving of an air pump or the like is unnecessary, and fuel consumption is improved.

According to the second aspect of the invention, since the electric heating means is energized while the introduction of the exhaust gas into the filter unit is regulated, the power consumption is reduced. In the invention according to claim 3, the air in the reserve tank can be supplied only to the filter unit in which the introduction of the exhaust gas is restricted, and the trouble of supplying the air to another filter unit by mistake can be avoided.

In the invention according to claim 4, since the particulates are collected by the tubular filter made of heat resistant fiber,
The amount of particulates deposited on each filter unit during regeneration is smaller than that when a honeycomb ceramic filter is used. Therefore, the amount of oxygen required for regeneration may be smaller, and the volume of the reserve tank can be reduced.

In the invention of claim 5, the preheated air is supplied to the filter unit, so that the amount of heat required to heat the supplied air to the combustion temperature of the particulates is reduced, and the electric power of the heater is reduced. The consumption can be reduced.

According to the sixth aspect of the invention, the air in the reserve tank can be supplied to the filter unit by a predetermined amount regardless of the pressure in the reserve tank by the action of the throttle valve provided in the second conduit.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an exhaust gas purifying apparatus according to a first embodiment.

FIG. 2 is a cross-sectional view of the exhaust gas purifying apparatus.

FIG. 3 is a sectional view of the exhaust gas purifying apparatus.

4A is a partial schematic configuration diagram of an exhaust gas purifying apparatus according to a second embodiment, and FIG. 4B is a partial sectional view of the exhaust gas purifying apparatus.

FIG. 5 is a schematic configuration diagram of a conventional device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Exhaust gas purifying device, 2 ... Diesel engine, 3 ... Exhaust passage, 4 ... Turbocharger as supercharger, 5 ... Surge tank as supercharging duct, 6 ... First pipeline, 7 ... Reserve tank, 8 ... Check valve, 9 ... Housing, 15 ... Filter unit, 17 ... Heater as electric heating means, 26 ... Controller as control means, 28 ... Valve constituting exhaust gas introduction regulation means, 29 ... Similarly driven gear,
30 ... also a motor, 31 ... similarly a driving gear, 32a ...
1st passage, 32b ... 2nd passage, 32c ... 3rd passage, 33
... Second pipe line, 34 ... Electromagnetic switching valve as valve, 35 ...
Orifice as a throttle valve.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location F02B 37/00 302 F02B 37/00 302Z

Claims (6)

[Claims] 1. An exhaust gas purifying apparatus, which is used by being connected to an exhaust passage of an engine with a supercharger, and in which a plurality of filter units are installed in parallel in a housing, wherein a first supercharging duct of the engine is provided. A reserve tank connected through a pipe, a check valve provided in the first pipe and opened when the supercharging pressure is equal to or higher than a set pressure, a passage for communicating the filter unit with the outside of the housing, An engine with a supercharger, comprising: a second pipeline that connects the reserve tank and the passage; a valve provided in the second pipeline; and a control unit that controls the operation of the valve when the filter unit is regenerated. Exhaust gas purification device. 2. The exhaust gas purifying apparatus comprises an electric heating means in each of the filter units, and an exhaust gas introduction restricting means for restricting the introduction of the exhaust gas into each filter unit when the filter unit is regenerated. At least the passage is provided. When each filter unit regulates the introduction of exhaust gas by the exhaust gas introduction regulation means, the filter unit communicates with the outside of the housing, and the control means connects the exhaust gas introduction regulation means and the electric heating means during regeneration of the filter unit. The exhaust gas purifying apparatus for an engine with a supercharger according to claim 1, which controls operation. 3. The passage according to claim 2, wherein at least a part of the passage is formed in the exhaust gas introduction regulating means, and the passage is opened at a position corresponding to the opening of the filter unit whose exhaust gas introduction is regulated by the exhaust gas introducing regulation means. Exhaust gas purification device for engine with supercharger. 4. The filter unit comprises a tubular filter part made of heat resistant fiber and closed at one end, and the exhaust gas introduction regulation means has a closed position for closing an exhaust gas introduction opening of each filter unit, The valve according to claim 2 or 3, further comprising: a valve movably provided in an open position for opening the opening and a drive means for moving the valve into a closed position and an open position for a predetermined filter unit. Exhaust gas purification device for engine with supercharger described. 5. The exhaust gas purifying apparatus for an engine with a supercharger according to claim 1, wherein at least a part of the second pipeline is arranged in an exhaust passage of the engine. . 6. The exhaust gas purifying apparatus for an engine with a supercharger according to claim 1, wherein a throttle valve is provided in the second pipeline.