JP2970265B2 - Exhaust particulate removal equipment for diesel engines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for removing particulates from an exhaust gas of a diesel engine, and more particularly, to a device for discharging a regenerated combustion gas when a filter that collects a predetermined amount of particulates contained in the exhaust gas of a diesel engine is regenerated. The present invention relates to a device for removing exhaust particulates of a diesel engine in which unburned gaseous substances in a combustion gas are completely burned in the middle of a discharge pipe, which is discharged to the outside by a pipe.

[0002]

2. Description of the Related Art The exhaust gas of an internal combustion engine, particularly a diesel engine, contains exhaust particulates (particulates) containing carbon as a main component and causes black smoke. From the viewpoint of environmental pollution, it is desirable to remove the particulates. In recent years, it has been proposed to dispose a ceramic filter in an exhaust passage of a diesel engine and remove the diesel particulates with the filter.

[0003] In an exhaust particulate removing device configured to remove particulates by a ceramic filter arranged in an exhaust passage of a diesel engine, the particulates collected inside the particulate filter are used with the use of the particulate filter. When the amount increases, the air permeability gradually decreases, and the engine performance deteriorates. Therefore, it is necessary to periodically regenerate a filter in which particulates are collected to some extent. To regenerate the filter, the electric heater is energized or the burner is ignited to ignite the particulates collected by the filter and supply a regeneration gas (hereinafter simply referred to as regeneration gas), for example, secondary air. This is done by burning it.

[0004] The determination of the regeneration timing is based on the travel distance of the engine,
Although it may be performed based on the operating time of the engine or the like, in general, in a conventional exhaust gas purification device for an internal combustion engine, the amount of particulates collected in the filter is detected to determine the regeneration time. I have. The detection of the amount of trapped particulates in the filter is usually detected by the pressure of the exhaust gas on the upstream side of the particulate filter and the differential pressure (pressure loss) on the downstream side, and the pressure loss value is larger than a predetermined value. It is determined that it is time to regenerate when it has become.

[0005] When secondary air is supplied as a regenerating gas during regeneration of the filter and the particulates collected in the filter are burned, the combustion gas is generally the same exhaust pipe as the exhaust gas or exhaust gas. What is the exhaust pipe
Released into the atmosphere through another dedicated exhaust pipe. Japanese Patent Application Laid-Open No. 63-180715 discloses that a particulate filter is provided in an exhaust passage, the filter is shut off from exhaust gas when a regeneration timing is reached, and secondary air is supplied to the filter from an air supply means to remove the filter. A system that regenerates and discharges combustion gas to the atmosphere from a dedicated exhaust pipe is disclosed.

[0006]

However, in the technique described in Japanese Patent Application Laid-Open No. 63-180715, there is a risk that unburned gaseous substances contained in the combustion gas may be discharged into the atmosphere. Therefore, the present invention has solved the problems of the conventional diesel engine exhaust particulate removal apparatus,
When regenerating a filter that burns particulates collected by the filter, a diesel engine exhaust particulate removal device that can discharge combustion gas to the atmosphere after completely combusting unburned gaseous substances in the combustion gas. The purpose is to provide.

[0007]

According to a first aspect of the present invention, there is provided an exhaust particulate removal apparatus for a diesel engine which achieves the above-mentioned object, and collects particulates in exhaust gas by a filter provided in an exhaust passage of the internal combustion engine. At a predetermined time, the particulates collected in the filter are ignited and the regeneration gas is supplied to perform combustion regeneration of the filter, and the combustion gas is supplied to the exhaust passage upstream or downstream of the filter. In the exhaust particulate removal device for a diesel engine that discharges to the outside by a dedicated exhaust pipe provided separately, a catalyst is provided in the exclusive exhaust pipe, and warm-up means for warming up the catalyst at the time of regeneration of the filter is provided . , Catalyst
The filter is installed near the casing of the filter . Further, the second object of the present invention to achieve the above object is as follows.
Exhaust particulate removal device for diesel engine
The filter in the exhaust passage of the
Collects the particulates and puts them in the filter at a predetermined time.
Ignition of collected particulates and regeneration gas
To perform combustion regeneration of the filter,
On the upstream or downstream side of the filter, separate from the exhaust passage
Diesel exhausted through a special exhaust pipe installed in
In the exhaust particulate removing device for an engine, the exclusive exhaust pipe is provided.
In addition to providing a suction pump for sucking the regeneration gas,
The fact that the catalyst was layered on the surface of the impeller in this pump
Features.

Further , in a third aspect of the present invention, there is provided a diesel engine exhaust particulate removing apparatus according to a third aspect of the present invention, wherein particulates in exhaust gas are collected by a filter provided in an exhaust passage of the internal combustion engine. The particulates collected in the filter are ignited and the regeneration gas is supplied to perform regeneration and combustion of the filter. The combustion gas is provided on the upstream or downstream side of the filter separately from the exhaust passage. In the exhaust particulate removal device for a diesel engine which discharges to the outside through a discharge pipe,
A catalyst is provided inside the filter, and when the filter is regenerated,
A warm-up means for warming up the catalyst is provided, and a casing of the catalyst is provided.
Is covered with a heat insulating member . Further,
A fourth aspect of the present invention, a diesel engine
The exhaust particulate removal device is a fan provided in an exhaust passage of an internal combustion engine.
Filter particulates in exhaust gas with filters
And the particulate matter collected in the filter at a predetermined time.
Ignition rate and supply of regeneration gas to filter
Combustion regeneration is performed, and the combustion gas is transferred upstream of the filter or
Is a dedicated exhaust pipe provided on the downstream side separately from the exhaust passage.
Removal of diesel engine exhaust particles discharged to the outside
In the device, when a catalyst is provided in the exclusive exhaust pipe,
A warm-up hand for warming up the catalyst during regeneration of the filter.
A stage, a line upstream of the catalyst of the dedicated discharge tube
To heat the combustion gas flowing in this pipeline.
And arranged so as to pass through the inside of the exhaust passage.
It is characterized by. Furthermore, the exhaust particulate filter of the fifth embodiment of the diesel engine of the present invention to achieve the object is to collecting particulates in exhaust gases by a filter provided in an exhaust passage of an internal combustion engine, wherein the predetermined timing The particulates trapped in the filter are ignited and the regeneration gas is supplied to perform combustion regeneration of the filter, and the combustion gas is provided on the upstream side or the downstream side of the filter by a dedicated discharge provided separately from the exhaust passage. In a device for removing exhaust particulates of a diesel engine which is discharged to the outside by a pipe, a catalyst is provided in the dedicated discharge pipe, and a casing of the catalyst is configured as a double pipe having the exhaust passage as an inner pipe,
The catalyst is provided around the exhaust passage.

[0009]

According to the first and third to fifth embodiments of the present invention, at the time of regenerating the particulates collected in the filter, the catalyst provided in the exclusive exhaust pipe is used. Is warmed up, the catalyst reaches the activation temperature when the combustion gas is discharged, and the unburned gaseous substances in the combustion gas are completely burned. Further, according to the exhaust particulate removing device of the second embodiment of the present invention, the catalyst is laminated on the surface of the impeller of the suction pump provided at the end of the exclusive discharge pipe for sucking the regeneration gas. When the combustion gas is sucked by the pump and passes through the impeller therein, the unburned gaseous substance in the combustion gas is completely burned by the rotation of the impeller.

[0010]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 shows a schematic configuration of an apparatus 20-1 for removing particulates of exhaust gas of a dual-filter type diesel engine of simultaneous collection and backflow alternating regeneration according to a first embodiment of the present invention. In the exhaust particulate removing device 20-1 for a diesel engine according to this embodiment, an exhaust pipe 2 for guiding exhaust gas from the engine 1 is branched into branch pipes 2A and 2B at a branch part a, and then merged at a merge part b. , 2D between exhaust
Through the muffler 6. First and second casings 3A and 3B provided in the middle of the branch pipes 2A and 2B are used to collect particulates in exhaust gas.
A filter 5A and a second filter 5B are provided.

Each of the filters 5A and 5B is a honeycomb filter provided with a partition made of a porous material such as a ceramic, and is generally cylindrical and has a large number of rectangular parallelepiped passages (filters) surrounded by the partition. Cell). The adjacent passages are alternately plugged with ceramic plugs on the exhaust gas inflow side and the exhaust gas outflow side to form a closed passage. Therefore, the particulates in the exhaust gas flowing into the filters 5A and 5B are collected by the filter cells when the exhaust gas passes through the wall surfaces of the filter cells.

Further, pressure introduction pipes SPU and SPD are provided on the upstream side of the branch section a of the branch pipes 2A and 2B and on the downstream side of the junction b, respectively. And the pressure on the downstream side of the junction b. Then, the pressure difference (pressure loss) between the upstream and downstream of the filters 5A and 5B is obtained by the differential pressure sensor 10, and the detected value is input to the ECU (control circuit) 100. The control circuit 100 determines the regeneration timing of the filters 5A and 5B based on the pressure difference (differential pressure).

On the other hand, plugs (not shown) near the downstream end surfaces of the filters 5A and 5B or at the downstream end are provided with electric heaters HA and HB for heating the filters and igniting the particulates during filter regeneration. One end of each of the electric heaters HA and HB is grounded, and the other end is connected to the battery 11 via switches SWA and SWB controlled by the control circuit 100. Furthermore, filter 5
A temperature sensor ST for detecting the exhaust gas temperature is provided upstream of A and 5B, and the exhaust gas temperature ThE from the temperature sensor ST is also input to the control circuit 100.
Although not shown, the engine 1 is provided with an intake air temperature sensor for detecting the intake air temperature and a water temperature sensor for detecting the temperature of the engine 1 based on the water temperature. The intake air temperature ThA detected by these sensors is provided. And the water temperature ThW are also input to the control circuit 100.

The branch part a is provided with a first control valve V1 for distributing the flow of exhaust gas from the exhaust pipe 2 upstream of the branch part a to the branch pipes 2A and 2B. A second control valve V2 for switching the connection of the pipes 2A and 2B to the exhaust pipe 2D on the downstream side of the junction b is provided. These control valves V1 and V2 are both driven by a control circuit 100. The control valves V1 and V2 are controlled by a control signal from the control circuit 100 so that the control valves V1 and V2 do not block any of the branch pipes 2A and 2B. It is positioned at a position to close one of the tubes 2A, 2B.

When reproducing the filters 5A and 5B described above,
It is necessary to energize the electric heater HA or HB, flow regeneration gas from the downstream side of the filter 5A or filter 5B on the energized side, and discharge combustion gas from the upstream side. Therefore, in this embodiment, the branch pipe 2
A regeneration gas supply pipe 7 is provided between the junction b of A and 2B and the filters 5A and 5B, and an electric air pump 9 for supplying secondary air is provided at one end of the regeneration gas supply pipe 7. ing. A check valve V3 is provided in the regeneration gas supply pipe 7 on the secondary air discharge side of the electric air pump 9, and an opening / closing valve V5 is provided at a connection portion of the regeneration gas supply pipe 7 to the branch pipes 2A and 2B. , V6 are provided.

A combustion gas discharge pipe 8 is provided between the branch portions a of the branch pipes 2A and 2B and the filters 5A and 5B. One end of the combustion gas discharge pipe 8 is closed, and the other end is a heater. It is open to the atmosphere via a catalyst CA containing H. One end of the heater H is grounded, and the other end is connected to the battery 11 via a switch SWC controlled by the control circuit 100. And the combustion gas discharge pipe 8
A check valve V4 is provided on the upstream side of the catalyst CA, and on-off valves V7 and V8 are provided at connecting portions of the combustion gas discharge pipe 8 to the branch pipes 2A and 2B, respectively. These valves V
3 to V8 and the electric air pump 9
Is driven and controlled.

The driving of the valves V1 to V8 is actually performed by a diaphragm type actuator, a negative pressure switching valve, or an electric type actuator, but the driving mechanism is not particularly limited. And its description is omitted. The control circuit 100 includes, for example, an interface INa for inputting an analog signal, an interface INd for inputting a digital signal, a converter A / D for converting an analog signal to a digital signal, a central processing unit CPU for performing various arithmetic processing, a random access memory RA.
M, a read-only memory ROM, a backup memory B that retains data even when the key switch of the engine is turned off.
The microcomputer includes a RAM, an output circuit OUT, and a bus line 111 for connecting the RAM and the like, but a detailed description of the operation of the microcomputer will be omitted.

An interface INa for inputting an analog signal of the control circuit 100 includes a particulate filter 5.
A, the differential pressure signal PD of the exhaust gas on the upstream and downstream sides of 5B,
An intake temperature signal ThA and a water temperature signal ThW of the engine 1 and an engine speed signal Ne from a speed sensor (not shown) are input, and a signal from a key switch and the like are input to the digital signal input interface INd.

Next, the operation of the exhaust gas particulate removal apparatus 20-1 for a diesel engine according to the first embodiment configured as described above will be described. When collecting particulates in the exhaust gas, the control valves V1 and V2 are controlled to neutral positions, and the check valves V3 and V4 and the on-off valves V5 to V8 are closed. FIG. 1 shows this state, and the exhaust gas discharged from the diesel engine 1 flows through both the branch pipes 2A and 2B as indicated by solid arrows, and the filters 5A and
The particulates are removed by 5B and the muffler 6
Released into the atmosphere via

When the trapped amount of the particulates in the filters 5A and 5B exceeds a predetermined value, and the differential pressure detection values on the upstream and downstream sides of the filters 5A and 5B of the differential pressure sensor 10 exceed the reference values, the filter is stopped. Is executed from the filter 5A. At this time, the secondary air supply control and the heater H
FIG. 2 shows how the energization control of A and HB and the energization control of the heater H for the catalyst CA are performed. When the filter 5A is regenerated, the control valves V1 and V2 close the inlet and outlet sides of the branch pipe 2A as indicated by the dotted lines, and the check valves V3 and V4 and the on-off valves V5 and V7 are opened. The secondary air from the air pump 9 is supplied to the filter 5A through the regeneration gas supply pipe 7 as shown by the dotted line (50 to 60 L / min), and the heater HA
Is applied for about 5 minutes to burn the particulates in the filter 5A, and the combustion gas passes through the combustion gas discharge pipe 8 to completely burn unburned gaseous substances in the catalyst CA and is discharged to the atmosphere. You. In the present embodiment, the energization of the heater H of the catalyst CA is performed simultaneously with the start of the regeneration process of the filter 5A, and is continued until the end of the regeneration process of the filter 5B. At this time, electric power of about 0.2 KW is supplied to the heater H. At the time of regeneration of the filter 5B, the control valves V1 and V2 block the inlet side and the outlet side of the branch pipe 2B, and the check valves V3 and V3.
V4 remains open and the on-off valves V5 and V7 close, and the on-off valve V
6, V8 is opened. The secondary air from the air pump 9 is supplied to the filter 5B through the regeneration gas supply pipe 7, and the heater HB is energized for about 5 minutes to burn the particulates in the filter 5B. The unburned gaseous substances are completely burned in the catalyst CA through 8 and discharged to the atmosphere.

As described above, in the exhaust particulate removing apparatus 20-1 for the diesel engine of the embodiment of FIG. 1, during the regeneration processing of the particulates collected in the filter,
Since the regenerated combustion gas is exhausted to the atmosphere after being completely burned by the catalyst CA that has reached the activation temperature by the heater H, the unburned gaseous substances are not exhausted to the atmosphere.

FIG. 3 shows a simultaneous trapping and backflow alternate regeneration type exhaust particulate removing apparatus 20- according to a second embodiment of the present invention.
2 shows a schematic configuration of a diesel engine, in which the position of the catalyst CA attached to the combustion gas exhaust pipe 8 is different from that of the diesel engine exhaust particle removing device 20-1 of the first embodiment shown in FIG. . Therefore, in the embodiment of FIG. 3, the same components as those of the embodiment of FIG. 1 are denoted by the same reference numerals, and the description thereof will be omitted. The configuration of the control unit will be omitted, and only the portions different from the embodiment of FIG. explain.

In the embodiment shown in FIG. 3, both ends of the combustion gas discharge pipe 8 are closed, the catalyst CA is disposed between the casings 3A and 3B of the particulate filters 5A and 5B, and the inlet of the combustion gas of the catalyst CA is provided. The side is connected to the vicinity of the center of the combustion gas discharge pipe 8 via a check valve V4. A heater H is built in the catalyst CA as in the first embodiment,
As in the first embodiment, one end of the heater H is grounded, and the other end is connected to the battery 11 via a switch SWC controlled by the control circuit 100. As described above, the catalyst CA is used as the casing 3A for the filters 5A and 5B,
3B, the catalyst 5C is trapped by the heat of the filters 5A and 5B that trap exhaust gas during operation of the engine.
A is being heated. Therefore, it is possible to reduce the amount of electricity supplied to the heater H incorporated in the catalyst CA during regeneration.

When the differential pressure detection value of the differential pressure sensor 10 exceeds the reference value, the filter regeneration processing is executed from the filter 5A. At this time, the supply control of the secondary air, the heaters HA and HB
FIG. 4 shows the state of the energization control of the catalyst H and the energization control of the heater H for the catalyst CA. During regeneration of the filter 5A, the control valve V
3, V1 and V2 close the inlet side and the outlet side of the branch pipe 2A, as shown in FIG.
7 opens. The secondary air from the air pump 9 is supplied to the filter 5A through the regeneration gas supply pipe 7 as shown by the dotted line (50 to 60 L / min), and the heater HA is energized for about 5 minutes, so that the The curate burns, and the combustion gas passes through the combustion gas discharge pipe 8 to the catalyst C.
In A, the unburned gaseous substances are completely burned and discharged into the atmosphere. In the present embodiment, the energization of the heater H of the catalyst CA is performed simultaneously with the start of the regeneration process of the filter 5A, and is continued until the end of the regeneration process of the filter 5B. At this time, the power supply to the heater H is about 0.1 KW, which is about half of the amount of electricity to the heater H in the embodiment shown in FIG. The regeneration of the filter 5B is performed in the same manner as the filter 5A, and the combustion gas is discharged to the combustion gas discharge pipe 8A.
Then, the unburned gaseous substances are completely burned in the catalyst CA and discharged to the atmosphere. As a result, in the diesel engine exhaust particulate removing apparatus 20-2 of the embodiment in FIG.
Since the combustion gas at the time of the regeneration treatment is exhausted to the atmosphere after being completely burned in the catalyst CA which has reached the activation temperature by the heater H, the unburned gaseous substance is not exhausted to the atmosphere.

FIG. 5 shows an exhaust particulate removing apparatus 20- of a simultaneous collection and backflow alternating regeneration type according to a third embodiment of the present invention.
3 shows a schematic configuration of a diesel engine exhaust particulate removing apparatus 20-1 of the first embodiment shown in FIG.
The only difference is that the casing of the catalyst CA has a heat retaining effect. Therefore, in the embodiment of FIG. 5, the same components as those of the embodiment of FIG. 1 are denoted by the same reference numerals, and the description thereof will be omitted, and only the portions different from the embodiment of FIG. 1 will be described.

In the embodiment shown in FIG. 5, the casing of the catalyst CA provided on the opening side of the combustion gas discharge pipe 8 is covered with a heat retaining member 12. As the heat retaining member 12, a fiber heat insulating material such as glass wool or a high-performance heat insulating material containing ceramic fine particles can be used, but a heat storage material such as calcium hydroxide or magnesium hydroxide may be used. Can be. As described above, when the casing of the catalyst CA is covered with the heat insulating material or the heat storage material, the heat of the catalyst CA does not easily escape and the catalyst CA does not easily cool. Therefore, it is possible to reduce the amount of electricity supplied to the heater H incorporated in the catalyst CA during regeneration.

When the differential pressure detection value of the differential pressure sensor 10 exceeds the reference value, the filter regeneration processing is executed from the filter 5A. At this time, the supply control of the secondary air, the heaters HA and HB
6 (a) and 6 (b) show the state of the energization control and the energization control of the heater H for the catalyst CA. FIG. 6 (a) shows the energization control characteristics of the heater H when the heat insulating material is attached to the casing of the catalyst CA, and FIG. 6 (b) shows the heater H when the heat storage material is attached to the casing of the catalyst CA. 5 shows the current-carrying control characteristics of FIG.

In the control example of FIG. 6 (a), when the filter 5A is regenerated, first, the heater H of the catalyst CA is preheated for a predetermined time, for example, about 2 minutes, with an electric power of 0.2 kW. After the end of the preheating, the control valves V1 and V2 close the inlet side and the outlet side of the branch pipe 2A as shown by the dotted lines in FIG. 5, and the check valves V3, V4 and the on-off valves V5, V7 are opened. The secondary air from the air pump 9 is supplied to the filter 5A through the regeneration gas supply pipe 7 as shown by the dotted line (50 to 60 L).
/ Min), the heater HA is energized for about 5 minutes to burn the particulates in the filter 5A, and the combustion gas passes through the combustion gas discharge pipe 8 so that the unburned gaseous substance is completely burned in the catalyst CA. Is released into the atmosphere. The energization of the catalyst CA to the heater H after the preheating is maintained at about 0.1 KW until the end of the regeneration processing of the filter 5B in this embodiment, and is about half of the energization amount to the heater H in the embodiment shown in FIG. It has become. This is because the heat preheated before the regeneration of the filter 5A is held by the heat insulating material.
The regeneration of the filter 5B is performed in the same manner as the regeneration of the filter 5A, and the combustion gas passes through the combustion gas discharge pipe 8 so that the unburned gaseous substances are completely burned in the catalyst CA and discharged to the atmosphere.

In the control example shown in FIG.
At the time of regeneration of A, first, the heater H of the catalyst CA is preheated for a predetermined time, for example, about 2 minutes, with a power supply of 0.5 kW. After the end of the preheating, the control valves V1 and V2 close the inlet side and the outlet side of the branch pipe 2A as shown by the dotted lines in FIG. 5, and the check valves V3, V4 and the on-off valves V5, V7 are opened. The secondary air from the air pump 9 is supplied to the filter 5A through the regeneration gas supply pipe 7 as shown by the dotted line (5).
0-60 L / min), the heater HA is energized for about 5 minutes, and the particulates in the filter 5A burn,
The combustion gas passes through the combustion gas discharge pipe 8 and the unburned gaseous substance is completely burned in the catalyst CA and discharged to the atmosphere. Since the amount of heat obtained by the preheating is maintained by the heat storage material, energization of the heater of the catalyst CA during the filter regeneration is not performed until the regeneration process of the filter 5B is completed. Control valves V1 and V2, check valve V during regeneration of filter 5B
3, V4 and on / off valves V5, V7, heaters HA,
The control of energization of the HB and the control of the supply of the secondary air from the air pump 9 are the same as those in the above-described embodiment, and the combustion gas passes through the combustion gas discharge pipe 8 to completely burn the unburned gaseous substances in the catalyst CA. And released into the atmosphere. As a result, also in the exhaust particulate removal device 20-3 of the diesel engine of the embodiment in FIG. 5, the regenerated combustion gas is exhausted to the atmosphere after being completely burned in the catalyst CA that has reached the activation temperature by the heater H. Unburned gaseous substances are not released into the atmosphere.

FIG. 7 shows an exhaust particulate removing apparatus 20- of a simultaneous trapping and backflow alternating regeneration type according to a fourth embodiment of the present invention.
4 shows a schematic configuration of a diesel engine exhaust particulate removing device 20-3 according to a third embodiment shown in FIG.
5 shows a modified embodiment in which the casing of the catalyst CA is covered with a heat insulating material as the heat retaining member 12. Therefore, in the embodiment of FIG. 7, the same components as those of the embodiment of FIG. 5 are denoted by the same reference numerals, and the description thereof will be omitted, and only the portions different from the embodiment of FIG. 5 will be described.

In the embodiment shown in FIG. 7, a portion 8A of the combustion gas discharge pipe 8 between the combustion gas discharge pipe 8 and the catalyst CA covered with the heat retaining member 12 passes through the exhaust pipe 2. The heat of the exhaust gas flowing in the exhaust pipe 2 heats the combustion gas flowing through the combustion gas discharge pipe 8. As a result, the heater H built in the catalyst CA during regeneration is
It is possible to reduce the amount of electricity to the power supply.

When the amount of trapped particulates in the filters 5A and 5B exceeds a predetermined value, the filter 5 of the differential pressure sensor 10
When the differential pressure detection values on the upstream and downstream sides of A and 5B exceed the reference value, the filter regeneration processing is executed from the filter 5A. At this time, the supply control of the secondary air, the heaters HA and HB
FIG. 8 shows the state of energization control of the catalyst H and the energization control of the heater H for the catalyst CA. The heater H is controlled by the filter 5A.
Is performed at the same time as the regeneration of the heater 5B.
Supply of power of about 1 KW is maintained. The supply of power to the heater H at this time is about half of the amount of power supplied to the heater H in the embodiment shown in FIG. Filter 5
Control valves V1, V2, check valve V during regeneration of A, 5B
3, V4 and on / off valves V5, V7, heaters HA,
The control of energization to the HB and the control of the supply of the secondary air from the air pump 9 are the same as in the above-described embodiment. And released into the atmosphere. As a result, also in the exhaust gas particulate removal apparatus 20-4 of the diesel engine of the embodiment in FIG.
The exhaust gas is exhausted to the atmosphere after being completely burned in the catalyst CA that has reached the activation temperature, so that unburned gaseous substances are not exhausted to the atmosphere.

FIG. 9 (a) shows an exhaust particulate removal apparatus 2 of a simultaneous trapping and backflow alternating regeneration type according to a fifth embodiment of the present invention.
FIG. 4 shows a schematic configuration of the exhaust gas particulate removal apparatus 20-1 of the diesel engine of the first embodiment shown in FIG. Therefore, in the embodiment of FIG. 9, the same components as those of the embodiment of FIG. 1 are denoted by the same reference numerals, and the description thereof will be omitted. The configuration of the control unit will be omitted, and only the portions different from the embodiment of FIG. explain.

In the embodiment shown in FIG. 9A, the combustion gas discharge pipe 8
Is closed, the other end is extended, and after a check valve V4 is provided therein, a casing accommodating the catalyst CA is further extended to form a double pipe with the exhaust pipe 2. That is, the casing accommodating the catalyst CA is disposed outside the exhaust pipe 2, the heat storage material 12 is attached inside the casing, and the catalyst CA is provided inside the heat storage material 12 and around the exhaust pipe 2. . Unlike the previous embodiments, the catalyst CA is not provided with a heater H. Thus, when the catalyst CA is arranged outside the exhaust pipe 2, the catalyst CA is always heated by the heat of the exhaust gas passing through the exhaust pipe 2 during operation of the engine. Therefore, since the catalyst CA has reached the activation temperature during regeneration, a heater is not required.

When the amount of trapped particulates in the filters 5A and 5B exceeds a predetermined value, the filter 5 of the differential pressure sensor 10
When the differential pressure detection values on the upstream and downstream sides of A and 5B exceed the reference value, the filter regeneration processing is executed from the filter 5A. At this time, the supply control of the secondary air and the heaters HA, HB
FIG. 9B shows the state of the energization control. Filter 5A, 5
Control valves V1, V2, check valves V3, V4 during regeneration of B
The control of the opening / closing valves V5 and V7, the control of energization of the heaters HA and HB, and the control of the supply of the secondary air from the air pump 9 are the same as those in the above-described embodiment, and the combustion gas passes through the combustion gas discharge pipe 8. The unburned gaseous substances are completely burned in the catalyst CA and discharged into the atmosphere.

As described above, in the exhaust particulate removing apparatus 20-5 of the diesel engine of the embodiment shown in FIG. 9 (a), the regeneration combustion gas also has an active temperature during the regeneration processing of the particulates collected in the filter. Is exhausted to the atmosphere after being completely burned in the catalyst CA that has reached the above, so that unburned gaseous substances are not emitted to the atmosphere. FIG.
Shows a schematic configuration of an exhaust particulate removing device 20-6 of a simultaneous collection and backflow alternating regeneration type in a sixth embodiment of the present invention, in which secondary air is supplied by a suction type air pump 9. It is. FIG. 11 shows a schematic configuration of an exhaust particulate removing apparatus 20-7 of a simultaneous trapping and forward-flow alternating regeneration type according to a seventh embodiment of the present invention. 9. The difference between these two embodiments from the above-mentioned five embodiments is that the catalyst CA is not provided at the end of the combustion gas discharge pipe 8, but is provided in a suction type air pump 9. Other configurations are the same as those of the first to fifth embodiments described above.
To 20-5. (However, since the seventh embodiment is a forward flow regeneration type, the regeneration gas supply pipe 7 is connected to the control valve V1 and the branch pipes 2A, 2B in the middle of the filters 5A, 5B, and the combustion gas discharge pipe 8 Is connected to the control valve V2 and the branch pipes 2A and 2B in the middle of the filters 5A and 5B.) Therefore, in the embodiments of FIGS. 10 and 11, the same components as those in the previous embodiments are included. The same reference numerals are given and the description is omitted.

In the above five embodiments, the combustion gas is discharged through the combustion gas discharge pipe 8 at the time of regeneration of the filter. However, in the embodiments of FIGS. 10 and 11, the air pump 9 is suctioned at the time of regeneration. By the operation, the secondary air is sucked from the opening end of the regeneration gas supply pipe 7 and supplied to the filter 5A or the filter 5B, and the combustion gas passes through the air pump 9 and is discharged to the atmosphere. Therefore, in these two embodiments,
The catalyst CA is provided on an impeller in the air pump 9.

FIG. 12A is a side view of the air pump 9 provided in the embodiment of FIGS. In the figure, 90 is a casing of the air pump 9, 91 is a combustion gas suction port, 92 is a combustion gas discharge port, 93 is a motor section,
94 is attached to the rotating shaft of the motor unit 93 and rotates,
This is an impeller that performs a combustion gas suction operation. FIG. 12 (b)
FIG. 5 is a front view showing the impeller 94 taken out from the casing 90 of the air pump 9. The impeller 94 has a plurality of fins 95 projecting from the periphery thereof.
As shown in (c), the disk surface between the fins 95 is formed so as to gradually decrease in thickness toward the outer peripheral portion to form a concave portion 96. Then, the concave 96
It is catalyzed 97 child Ti ring on the outer surface of the fin 95 and. In this embodiment, the catalyst 97 is platinum (Pt) supported on an alumina coat.

[0039] In this embodiment, when the combustion gas at the time of regeneration process of the filter passes through the air pump 9 are agitated by the impeller surface co Ti ring catalyst 97 of the air pump 9, in contact with the impeller 94 during the stirring As a result, the unburned gaseous substances are completely burned and discharged into the atmosphere. As described above, the exhaust particle removing devices 20-6, 20- of the diesel engine according to the embodiment shown in FIGS.
In the process 7, the regenerated combustion gas is exhausted into the atmosphere after the regenerated combustion gas is completely burned by the rotating catalyst 97 during the regeneration process of the particulate matter collected in the filter, so that the unburned gaseous substances are emitted into the atmosphere. Never be.

[0040]

As described above, the first and second embodiments of the present invention are described.
According to the third to fifth aspects of the exhaust particulate removing apparatus for a diesel engine, the unburned gaseous substances in the combustion gas discharged at the time of regeneration of the filter are completely burned by the active catalyst and discharged to the atmosphere. Is done. Further, according to the exhaust particulate removing device for a diesel engine of the second embodiment of the present invention, the unburned gaseous substances in the combustion gas are completely burned by the rotating catalyst and discharged into the atmosphere. As a result, there is an effect that unburned gaseous substances are not released into the atmosphere when the filter is regenerated.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a schematic configuration of an exhaust particulate removal apparatus of a simultaneous collection and backflow alternating regeneration dual filter type according to a first embodiment of the present invention.

FIG. 2 is a control chart of secondary air and a heater at the time of reproduction in the first embodiment.

FIG. 3 is a partial configuration diagram showing a schematic configuration of an exhaust particulate removal apparatus of a simultaneous collection and backflow alternating regeneration dual filter type according to a second embodiment of the present invention.

FIG. 4 is a control chart of secondary air and a heater at the time of reproduction in a second embodiment.

FIG. 5 is a configuration diagram showing a schematic configuration of an exhaust particulate removal device of a simultaneous collection and backflow alternating regeneration dual filter type according to a third embodiment of the present invention.

FIG. 6A is a control chart of secondary air and a heater at the time of regeneration when the heat retaining member is a heat insulating material in the third embodiment, and FIG. 6B is a control chart of the heat retaining member in the third embodiment; It is a control chart of a secondary air and a heater at the time of reproduction at the time of material.

FIG. 7 is a configuration diagram showing a schematic configuration of an exhaust particulate removal device of a simultaneous collection and backflow alternating regeneration dual filter type according to a fourth embodiment of the present invention.

FIG. 8 is a control chart of a secondary air and a heater at the time of reproduction in a fourth embodiment.

FIG. 9 (a) is a partial configuration diagram showing a schematic configuration of an exhaust particulate removal apparatus of a simultaneous collection and backflow alternating regeneration dual filter type according to a fifth embodiment of the present invention, and FIG. 10 is a control chart of secondary air and a heater at the time of regeneration in the example of FIG.

FIG. 10 is a configuration diagram showing a schematic configuration of an exhaust particulate removal apparatus of a simultaneous collection and backflow alternating regeneration dual filter type according to a sixth embodiment of the present invention.

FIG. 11 is a configuration diagram showing a schematic configuration of an exhaust particulate removal apparatus of a simultaneous collection and a forward flow alternating regeneration dual filter type according to a seventh embodiment of the present invention.

12 (a) is a side view of an air pump used in the embodiment of FIGS. 10 and 11, (b) is a front view of an impeller incorporated in the air pump of (a), (c) Is (b)
3 is a partially enlarged perspective view showing a part of the impeller of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Diesel engine 2 ... Exhaust pipe 2A, 2B ... Branch pipe 5A, 5B ... Filter 7 ... Regeneration gas supply pipe 8 ... Combustion gas discharge pipe 9 ... Air pump 10 ... Differential pressure sensor 12 ... Heat insulation member 100 ... Control circuit a ... Branch b b Merge CA CA H, HA, HB Electric heater V1 First control valve V2 Second control valve V3, V4 Check valve V5 to V8 Open / close valve

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kenji Kimura 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (56) References JP-A-5-272326 (JP, A) JP-A-5-231132 (JP, A) JP-A-4-183917 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F01N 3/02 301-341

Claims (6)

(57) [Claims] A filter provided in an exhaust passage of an internal combustion engine collects particulates in exhaust gas, ignites the particulates collected in the filter at a predetermined time, and supplies regeneration gas to the filter. A diesel engine exhaust particulate removal device that performs combustion regeneration of the exhaust gas and discharges the combustion gas to the outside by an exclusive exhaust pipe provided separately from the exhaust passage on the upstream or downstream side of the filter. provided with a catalyst, the warm-up means for warming up the catalyst during regeneration of the filter is provided, the exhaust particulate filter of a diesel engine, characterized in that installed the catalyst in the vicinity of the casing of the filter. 2. A filter provided in an exhaust passage of an internal combustion engine to collect particulates in exhaust gas, ignite the particulates collected in the filter at a predetermined time, and supply regeneration gas to the filter. The exhaust gas removal device for a diesel engine, which performs combustion regeneration of the exhaust gas and discharges the combustion gas to the outside by an exclusive exhaust pipe provided separately from the exhaust passage on the upstream side or the downstream side of the filter, And a suction pump for sucking the regeneration gas, and a catalyst is laminated on a surface of an impeller in the pump. Wherein the exhaust passage is branched into two on its way, its is the filter to each individual branch passages are provided, in that the combustion regeneration of the filters is performed alternately, the said catalyst 2 One of the exhaust particulate filter for a diesel engine according to claim 1, characterized in that installed between the casing of the filter. 4. A filter provided in an exhaust passage of an internal combustion engine.
Therefore, particulates in the exhaust gas are collected and
The particulates collected in the filter
Fire and supply regeneration gas to burn and regenerate filter
Do the combustion gas upstream or downstream of the filter
Externally by a special exhaust pipe provided separately from the exhaust passage.
Diesel engine exhaust particulate removal device
And a catalyst is provided in the exclusive discharge pipe, and the
Provided warm-up means for warming up the catalyst during regeneration of the motor, and characterized in that the casing of the catalyst was Tsu covered by heat insulating member
Exhaust particulate filter of the diesel engine to be. 5. A filter provided in an exhaust passage of an internal combustion engine.
Therefore, particulates in the exhaust gas are collected and
The particulates collected in the filter
Fire and supply regeneration gas to burn and regenerate filter
Do the combustion gas upstream or downstream of the filter
Externally by a special exhaust pipe provided separately from the exhaust passage.
Diesel engine exhaust particulate removal device
And a catalyst is provided in the exclusive discharge pipe, and the
Provided warm-up means for warming up the catalyst during regeneration of the motor, the upstream side of the conduit of the catalyst of the discharge pipe of the dedicated, in order to heat the combustion gas flowing through the conduit, the exhaust passage characterized by being arranged to pass through the inside of the
Exhaust particulate filter of the diesel engine. 6. A filter provided in an exhaust passage of an internal combustion engine to collect particulates in exhaust gas, ignite the particulates collected in the filter at a predetermined time, and supply regeneration gas to the filter. A diesel engine exhaust particulate removal device that performs combustion regeneration of the exhaust gas and discharges the combustion gas to the outside by an exclusive exhaust pipe provided separately from the exhaust passage on the upstream or downstream side of the filter. Wherein a catalyst is provided in the casing, and a casing of the catalyst is formed as a double pipe having the exhaust passage as an inner tube, and the catalyst is provided around the exhaust passage. .