JP2009293405A - Exhaust gas treating device in internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the occupied space of an exhaust gas treating device for burning particulate matter in exhaust gas. <P>SOLUTION: A separator 23 is interposed at an intermediate part of an exhaust pipe 22. The separator 23 comprises a storage part 231 and a particulate filter 232 stored in the storage part 231. The particulate matter in the exhaust gas is collected by the particulate filter 232. An air supply pipe 24 is branch-connected to an intake pipe 17. The air supply pipe 24 is connected to the storage part 231 of the separator 23, and a heat exchanger 25 is interposed at an intermediate part of the air supply pipe 24. A part of air delivered from a supercharger 19 is supplied into the separator 23 via the air supply pipe 24 and the heat exchanger 25. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an exhaust gas processing apparatus in an internal combustion engine that processes particulate matter in exhaust gas discharged from a combustion chamber of the internal combustion engine.

Patent Document 1 discloses a technical idea of burning particulate matter in exhaust gas. Particulate matter in the exhaust gas is separated from the exhaust gas using a filter, and the particulate matter deposited on the filter is dissociated from the filter by blowing high pressure air stored in the air tank onto the filter. . Particulate matter dissociated from the filter is accumulated in one place. The air in the air tank is blown onto the accumulated particulate matter, and the heat of the electric heater is used for ignition for burning the particulate matter.
Japanese Utility Model Publication No. 5-211117

  However, it is necessary to appropriately supply air to the air tank so that the high-pressure air in the air tank does not disappear, and a replenishing means for that purpose is required. The adoption of the exhaust gas processing device provided with the air tank and the replenishing means requires an occupied space for the surroundings of the internal combustion engine, which increases the occupied space of the internal combustion engine with the exhaust gas processing device. .

  An object of the present invention is to reduce the space occupied by an exhaust gas treatment device for burning particulate matter in exhaust gas.

  The present invention is directed to an exhaust gas processing apparatus in an internal combustion engine that processes particulate matter in exhaust gas discharged from a combustion chamber of the internal combustion engine. In the invention of claim 1, the invention includes the particulate matter. A feed pump that feeds air into an exhaust gas exhaust path is provided.

  The exhaust gas containing particulate matter is exhaust gas before separation of particulate matter or exhaust gas before combustion treatment of particulate matter. When the air sent into the exhaust path touches the particulate matter in the exhaust path, the particulate matter burns. Since air is directly fed into the exhaust path from the feed pump, an air tank and an air replenishing means are unnecessary, and the space occupied by the exhaust gas processing device is reduced.

  In a preferred example, an air supply path connected to the exhaust path is provided, the feed pump is arranged in the upstream of the air supply path or the air supply path, and the air fed from the feed pump is It is fed into the exhaust path through an air supply path.

Since air is directly sent from the feed pump to the air supply path, an air tank and an air replenishing unit are unnecessary, and the space occupied by the exhaust gas processing device is reduced.
In a preferred example, separation means for separating the particulate matter from the exhaust gas is provided in the exhaust path, and the separation means includes an accumulation place for collecting the separated particulate matter, The air supply path is connected to the accumulation location.

The accumulated particulate matter is easy to burn.
In a preferred example, a heat exchanger for heating air is provided in the air supply path.
Heated air tends to burn particulate matter.

In a preferred example, the heat exchanger receives the combustion heat of the internal combustion engine.
The combustion heat of the internal combustion engine is suitable as heat for heating air.
In a preferred example, the feed pump is driven using an exhaust gas flow.

A feed pump operated by an exhaust gas flow provides an energy saving effect.
In a preferred example, the feed pump is a supercharger that supercharges air into the combustion chamber.
A turbocharger that supercharges air into the combustion chamber eliminates the need for a dedicated feed pump. Moreover, since the air sent out by the supercharger is compressed, the temperature of the air sent out from the supercharger increases. High-temperature air tends to burn particulate matter.

  INDUSTRIAL APPLICABILITY The present invention has an excellent effect that it is possible to reduce the occupied space of an exhaust gas processing device for burning particulate matter in exhaust gas.

Hereinafter, a first embodiment in which the present invention is embodied in a diesel engine will be described with reference to FIGS. FIG. 1B is a schematic diagram of FIG.
As shown in FIG. 1A, a diesel engine 10 (internal combustion engine) includes a plurality of combustion chambers 11 (four in this embodiment) provided in a cylinder (not shown), and is connected to the cylinder. An electromagnetic fuel injection nozzle 13 is attached to the cylinder head 12 for each combustion chamber 11. The fuel injection nozzle 13 injects fuel into the combustion chamber 11.

  The fuel is supplied to the fuel injection nozzle 13 via the fuel pump 14 and the common rail 15, and the fuel injection nozzle 13 injects the fuel into each combustion chamber 11. The fuel injection nozzle 13 is controlled by a control device (not shown).

  An intake manifold 16 is connected to the cylinder head 12. An intake pipe 17 is connected to the intake manifold 16, and an air cleaner 18 is connected to the intake pipe 17. A compressor unit 191 and a throttle valve 20 of the supercharger 19 are disposed in the middle of the intake pipe 17 constituting the intake path from the upstream side. The supercharger 19 is a known turbocharger that is operated by an exhaust gas flow. The throttle valve 20 is for adjusting the air flow rate sucked into the intake pipe 17.

  An exhaust manifold 21 is connected to the cylinder head 12, and an exhaust pipe 22 is connected to the exhaust manifold 21. In the middle of the exhaust pipe 22, a turbine section 192 and a separation device 23 of the supercharger 19 are interposed. The separation device 23 includes a storage device 231 and a particulate filter 232 stored in the storage device 231. The particulate filter 232 is a filter for collecting particulate matter. The exhaust gas discharged from the combustion chamber 11 is released to the atmosphere via the exhaust manifold 21, the exhaust pipe 22, the turbine unit 192 and the separation device 23.

  An air supply pipe 24 is branched and connected to the intake pipe 17 upstream of the throttle valve 20 with respect to the intake path. The air supply pipe 24 is connected to the container 231 of the separation device 23, and a heat exchanger 25 is interposed in the air supply pipe 24. A part of the air that flows into the intake pipe 17 from the air cleaner 18 flows into the air supply pipe 24. The air flowing through the air supply pipe 24 that is an air supply path passes through the heat exchanger 25. The heat exchanger 25 is attached to the cylinder or the cylinder head 12 of the diesel engine 10. The heat exchanger 25 receives the combustion heat of the diesel engine 10 and transmits it to the air flowing in the heat exchanger 25.

  The supercharger 19 operating by the exhaust gas flow flowing through the exhaust pipe 22 compresses and sends out the air flowing from the air cleaner 18 to the intake pipe 17. A part of the air sent out from the supercharger 19 flows into the intake manifold 16, and the rest of the air sent out from the supercharger 19 flows into the air supply pipe 24. The air that has flowed into the air supply pipe 24 receives a part of the combustion heat of the diesel engine 10 via the heat exchanger 25, and the air that has received a part of the combustion heat of the diesel engine 10 is heated. The air heated in the heat exchanger 25 flows into the container 231 of the separation device 23. Exhaust gas flows from the exhaust pipe 22 into the storage device 231, and the particulate filter 232 in the storage device 231 collects particulate matter in the exhaust gas flowing into the storage device 231. Since the inside of the container 231 is at a high temperature (a temperature higher than the temperature necessary for burning the particulate matter) due to the heat of the exhaust gas, the particulate matter collected by the particulate filter 232 is air. The air that has flowed into the container 231 of the separation device 23 from the supply pipe 24 is touched and burned.

  The supercharger 19 is a feed pump that feeds air into the air supply pipe 24 using an exhaust gas flow. The separation device 23 is a separation means for separating particulate matter from the exhaust gas, and is a collection place for collecting the separated particulate matter. The exhaust manifold 21, the exhaust pipe 22 between the exhaust manifold 21 and the separation device 23, and the separation device 23 constitute an exhaust path for exhaust gas including particulate matter.

In the first embodiment, the following effects can be obtained.
(1) The air sent from the air supply pipe 24 to the separation device 23 is directly sent to the air supply pipe 24 by the operation of the supercharger 19. Since the supercharger 19 supercharges air, a large amount of air necessary for burning the particulate matter in the separation device 23 is sent into the separation device 23. The exhaust gas processing apparatus including the supercharger 19, the air supply pipe 24, and the separation device 23 eliminates the need for an air tank and air supply means as disclosed in Patent Document 1. The space occupied by the exhaust gas processing apparatus of the present embodiment that does not include an air tank and air supply means is reduced as compared with a conventional exhaust gas processing apparatus that includes an air tank and air supply means.

  (2) The particulate matter collected by the particulate filter 232 is accumulated in the particulate filter 232. For this reason, if air is concentratedly supplied to the particulate matter collecting area, which is the separation device 23, the accumulated particulate matter is easily brought into contact with the air. That is, the accumulated particulate matter is easy to burn. The configuration in which the air supply pipe 24 is connected to the particulate matter collecting place called the separation device 23 makes it easy to burn the particulate matter by concentrating air on the collected particulate matter.

  (3) The particulate matter collected by the particulate filter 232 can be directly burned on the particulate filter 232 without being dissociated from the particulate filter 232.

  (4) When the temperature in the separator 23 is low (when the temperature is lower than the temperature required for burning the particulate matter), the particulate matter in the separator 23 does not burn. Therefore, it is important not to lower the temperature in the separation device 23 as much as possible.

  The air supplied into the separation device 23 is heated to be passed through the heat exchanger 25. The air heated by passing through the heat exchanger 25 reduces the temperature drop in the separation device 23 compared to the unheated air. That is, the air heated by passing through the heat exchanger 25 easily burns particulate matter in the separation device 23.

  (5) The heat exchanger 25 transmits heat generated by the combustion to the air in the air supply pipe 24. The configuration using the combustion heat (exhaust heat) of the diesel engine 10 as heat for heating the air supplied into the separation device 23 is a configuration that does not waste when the particulate matter is burned.

  (6) The air sent out from the supercharger 19 is compressed and the temperature rises. The air whose temperature has increased contributes to the ease of combustion of the particulate matter in the separation device 23. The supercharger 19 that converts the kinetic energy of the exhaust gas into air preheat provides an energy saving effect.

(7) The supercharger 19 that supercharges air to the combustion chamber 11 eliminates the need for a dedicated feed pump.
Next, each embodiment of FIGS. 2 to 7 will be described. In any of the embodiments, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the second embodiment of FIG. 2, the heat exchanger 25 in the first embodiment is eliminated, but the air sent from the supercharger 19 is preheated and sent to the air supply pipe 24. In the second embodiment, the same effects as the items (1), (2), (3), (6), and (7) in the first embodiment can be obtained.

  In the third embodiment of FIG. 3, the entire amount of air flowing from the air cleaner 18 into the intake pipe 17 is supplied to the intake manifold of the diesel engine 10 as it is. On the other hand, an air supply pipe 24A is provided separately from the intake pipe 17, and a compressor unit 191 and a heat exchanger 25A of the supercharger 19 are interposed in the air supply pipe 24A. The heat exchanger 25A downstream of the compressor unit 191 receives heat from the cooling water for engine cooling and transmits it to the air flowing through the air supply pipe 24A. The cooling water flowing into the heat exchanger 25 </ b> A is cooling water after receiving heat from the diesel engine 10. The heat exchanger 25A takes out the combustion heat (exhaust heat) of the diesel engine 10 through the cooling water.

In the third embodiment, the same effects as the items (1) to (6) in the first embodiment can be obtained.
4 differs from the third embodiment only in that the heat exchanger 25A is on the upstream side of the compressor unit 191. In the fourth embodiment shown in FIG. In the fourth embodiment, the same effect as in the third embodiment can be obtained.

  In the fifth embodiment of FIG. 5, an electric pump 26 is arranged instead of the supercharger 19. Air is sent from the electric pump 26 to the air supply pipe 24A. As the electric pump 26, for example, a diaphragm pump, a screw pump, a scroll compressor, or the like is used. The electric pump 26 is controlled by a control device (not shown). Similar to the first embodiment, the heat exchanger 25 is attached to the cylinder or the cylinder head 12 of the diesel engine 10, receives the heat of combustion of the diesel engine 10, and transmits it to the air flowing in the heat exchanger 25.

In the fifth embodiment, the same effects as the items (1) to (5) in the first embodiment are obtained, and the following effects are obtained.
Employment of the electric pump 26 enables selection of the timing and period of air feeding into the air supply pipe 24A. For example, when the collected amount of particulate matter in the particulate filter 232 [see FIG. 1 (a)] increases and the collection function of the particulate filter 232 is likely to be lowered, the electric pump 26 is turned on for a predetermined time. As long as the collecting function of the separation device 23 is not lowered, the operation of the electric pump 26 can be stopped.

  The predetermined time is set to be longer than the time necessary to burn out all the particulate matter collected by the particulate filter 232. The decrease in the collection function can be predicted by, for example, calculating the integrated amount of the fuel injection amount.

The intermittent air supply to the air supply pipe 24 reduces the temperature drop in the separation device 23 compared to the case where air is continuously supplied to the air supply pipe 24.
In the sixth embodiment shown in FIG. 6, a heat exchanger 25B is interposed in the middle of the exhaust pipe 22 and in the middle of the air supply pipe 24A in place of the heat exchanger 25 in the fifth embodiment. The heat exchanger 25B transmits the heat of the exhaust gas flowing through the exhaust pipe 22 to the air flowing through the air supply pipe 24A.

In the sixth embodiment, the same effect as in the fifth embodiment can be obtained.
In the seventh embodiment shown in FIG. 7, the first exhaust pipe 22A connected to the exhaust manifold 21 [see FIG. Is connected. Further, a heat exchanger 25A is arranged in place of the heat exchanger 25. The turning cylinder 27 includes a cylindrical house-shaped cylindrical peripheral wall 271, a conical conical peripheral wall 272 connected to the lower part of the cylindrical peripheral wall 271, and a lid 273 connected to the upper part of the cylindrical peripheral wall 271. An accumulation cylinder 28 is connected to the lower part of the conical peripheral wall 272. The first exhaust pipe 22 </ b> A passes through the cylindrical peripheral wall 271 and communicates with the inside of the turning cylinder 27.

  A second exhaust pipe 22 </ b> B is connected to the turning cylinder 27. The second exhaust pipe 22 </ b> B passes through the lid 273 and communicates with the inside of the turning cylinder 27. The exhaust gas in the first exhaust pipe 22A flows into the turning cylinder 27, and the exhaust gas that flows into the turning cylinder 27 turns around the second exhaust pipe 22B in the turning cylinder 27. When the exhaust gas turns in the turning cylinder 27, the particulate matter is separated from the exhaust gas. The separated particulate matter is dropped and accumulated in the accumulation cylinder 28. The exhaust gas swirled in the swivel cylinder 27 flows into the second exhaust pipe 22B. The first exhaust pipe 22A, the turning cylinder 27, and the second exhaust pipe 22B constitute turning means (separation means) for turning the exhaust gas to separate the particulate matter in the exhaust gas.

  An air supply pipe 24 </ b> A is connected to the accumulation cylinder 28. The air in the air supply pipe 24 </ b> A flows into the accumulation cylinder 28. The particulate matter accumulated at the accumulation location in the accumulation cylinder 28 is combusted by the inflow of air from the air supply pipe 24A.

In the seventh embodiment, the same effects as in the items (1), (2), (4), (5) and the fifth embodiment in the first embodiment can be obtained.
In the present invention, the following embodiments are also possible.

In the fifth and sixth embodiments, the electric pump 26 may be attached to the container 231 of the separation device 23 so that air is directly fed into the separation device 23 from the electric pump 26.
In the seventh embodiment, the electric pump 26 may be attached to the integrated cylinder 28, and air may be sent directly from the electric pump 26 into the integrated cylinder 28.

In the fifth to seventh embodiments, the heat exchangers 25, 25A, 25B may be eliminated.
In the first embodiment, an intercooler for cooling the air flowing in the intake pipe 17 is provided in the middle of the intake pipe 17 upstream of the throttle valve 20, and the air supply pipe 24 is provided in the intake pipe 17 upstream of the intercooler. May be branched. The air cooled by the intercooler flows into the combustion chamber 11 without flowing into the air supply pipe 24. Air that has been cooled and increased in density is preferred for improving engine output.

The heat exchanger 25A is not limited to cooling water for engine cooling as a heat medium, but may be engine oil.
O Separation means for separating particulate matter from exhaust gas may be eliminated, and the air sent from the feed pump to the air supply pipe may be sent into the exhaust path. Particulate matter in the exhaust path burns in contact with the air sent into the exhaust path.

The present invention may be applied to a gasoline engine.
The technical idea which can be grasped from the above-described embodiment will be described together with the effect.
[1] The exhaust gas processing apparatus for an internal combustion engine according to claim 3, wherein the separation means is a separation device in which a particulate filter is housed in a particulate filter housing.

  Particulate matter collected in the particulate filter can be directly burned on the particulate filter.

1 is a schematic configuration diagram of an internal combustion engine and an exhaust gas processing device according to a first embodiment. (B) is a schematic diagram. The schematic diagram which shows 2nd Embodiment. The schematic diagram which shows 3rd Embodiment. The schematic diagram which shows 4th Embodiment. The schematic diagram which shows 5th Embodiment. The schematic diagram which shows 6th Embodiment. The schematic diagram which shows 7th Embodiment.

Explanation of symbols

  10: A diesel engine as an internal combustion engine. 11 ... Combustion chamber. 19 ... Supercharger as a delivery pump. 22, 22A, 22B ... Exhaust pipes constituting the exhaust path. 23: Separation means and separation device as a collection place. 24, 24A ... Air supply pipes as air supply paths. 25, 25A, 25B ... heat exchangers. 28: An accumulation cylinder as an accumulation place.

Claims (7)

In an exhaust gas processing apparatus in an internal combustion engine for processing particulate matter in exhaust gas discharged from a combustion chamber of the internal combustion engine,
An exhaust gas processing apparatus in an internal combustion engine, wherein a feed pump for feeding air into an exhaust path of the exhaust gas including the particulate matter is provided.   An air supply path connected to the exhaust path is provided, and the feed pump is disposed in the air supply path or upstream of the air supply path, and the air fed from the feed pump passes through the air supply path. The exhaust gas processing apparatus for an internal combustion engine according to claim 1, wherein the exhaust gas processing apparatus is sent to the exhaust path via the exhaust path.   Separating means for separating particulate matter from the exhaust gas is provided in the exhaust path, and the separating means includes an accumulation place for collecting the separated particulate matter, and the air supply path is The exhaust gas treatment device for an internal combustion engine according to claim 2, connected to the accumulation location.   The exhaust gas processing apparatus for an internal combustion engine according to claim 2 or 3, wherein a heat exchanger for heating air is provided in the air supply path.   The exhaust gas processing apparatus for an internal combustion engine according to claim 4, wherein the heat exchanger receives heat of combustion of the internal combustion engine.   The exhaust gas processing apparatus for an internal combustion engine according to any one of claims 1 to 5, wherein the feed pump is driven using an exhaust gas flow.   The exhaust gas processing apparatus for an internal combustion engine according to claim 6, wherein the feed pump is a supercharger that supercharges air into the combustion chamber.

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