JP4353745B2 - Exhaust gas purification device for internal combustion engine - Google Patents

Description

  The present invention relates to an exhaust gas purification device for an internal combustion engine, and more particularly to an exhaust gas purification device for an internal combustion engine that is provided in an exhaust passage of the internal combustion engine and includes an exhaust aftertreatment device.

    Conventionally, it is known to provide an exhaust gas purification device in an exhaust passage of an internal combustion engine in order to collect particulates discharged from an internal combustion engine such as a diesel engine or to reduce the amount of NOx.

  As an exhaust gas purifying device for collecting particulates, an exhaust gas purifying device comprising a diesel particulate filter (hereinafter referred to as DPF (Diesel Particulate Filter)) has been developed.

  As an exhaust gas purification device for reducing the amount of NOx, an exhaust gas purification device having an exhaust aftertreatment device including a NOx reduction catalyst (DeNOx catalyst) and a NOx storage reduction catalyst has been developed.

  In any of the exhaust aftertreatment devices of these exhaust gas purification devices, for example, a columnar carrier (core) made of cordierite, silicon carbide or the like is used. That is, in the exhaust aftertreatment device made of DPF, the exhaust gas flows in from one end surface side of the carrier and flows out from the other end surface, so that the carrier is used as a filter. Further, in the exhaust aftertreatment device including the NOx reduction catalyst and the NOx storage reduction catalyst, various catalysts are supported on the carrier, and NOx in the exhaust gas flowing through the carrier is reduced. These exhaust aftertreatment devices are housed in a bottomed cylindrical case, and constitute an exhaust gas purification device together with this case.

  In such an exhaust gas purifying device, an exhaust gas inlet chamber is provided on the upstream side of the exhaust aftertreatment device (upstream side in the exhaust gas flow direction) inside the case, and on the downstream side of the exhaust aftertreatment device ( An exhaust gas outlet chamber is provided on the downstream side in the flow direction of the exhaust gas. The inlet chamber communicates with the exhaust passage of the diesel engine through an inlet pipe, and the outlet chamber communicates with the outside through an outlet pipe.

  In general, when the inlet pipe and the outlet pipe are arranged on the axis, that is, in a straight line, the flow of the exhaust gas is smooth. Therefore, an exhaust gas purification device having such a configuration is known. (For example, patent document 1).

In this apparatus, on the upstream side of the exhaust aftertreatment device, a rectifying body is provided for making the exhaust gas uniform and flowing through the exhaust aftertreatment device. This rectifier has a structure in which the front and back surfaces of the corrugated plate are sandwiched between flat plates, and is formed in a spiral shape so as to have a cone shape that expands toward the downstream side.
Japanese National Patent Publication No. 02-502110

  However, in the prior art, since the corrugated plate and the flat plate are joined or the corrugated plate is provided with a slit in order to configure the rectifying body, a troublesome work is required and the configuration becomes complicated. In addition, after the corrugated plate is formed into a predetermined shape, the sandwiched plate must be wound into a cone and spirally to form a rectifier, and the rectifier is used as a diffuser. There is a problem that it must be fixed, and it is not easy to manufacture and attach.

  Further, in the above-described prior art, an example in which a rectifying body is constituted by an individually pre-processed truncated cone channel module or a rectangular channel module, and an increasing opening angle are arranged so as to be fitted and concentrically arranged. Although an example in which the rectifier is configured with a truncated cone surface is also disclosed, there is a problem in that it is not easy to manufacture and the flow of exhaust gas is difficult to equalize.

  An object of the present invention is to provide an exhaust gas purification device for an internal combustion engine that can make the flow of exhaust gas to the exhaust aftertreatment device uniform with a simple configuration and improve the function of the exhaust aftertreatment device. is there.

An exhaust gas purification device for an internal combustion engine according to claim 1 of the present invention is an exhaust gas purification device for an internal combustion engine provided in an exhaust passage of the internal combustion engine and provided with an exhaust post-treatment device, and includes the exhaust post-treatment device. a case, an upstream chamber provided upstream of an exhaust gas flow direction relative to said casing, the together the exhaust gas flows is provided on the upstream chamber, the downstream end of the exhaust gas flow direction is closed, and comprising an inlet pipe having a large number of small holes in the outer periphery, and an inner diameter tube expanding toward the downstream side in the flow direction of the exhaust gas from the longitudinal outer periphery of the middle position of the inlet pipe, the inner diameter The exhaust gas flowing simultaneously on both sides of the inner and outer peripheral surfaces forming the expanded portion of the pipe flows into the exhaust aftertreatment device .

  The exhaust gas purifying device for an internal combustion engine according to claim 2, wherein a portion forming the upstream chamber of the case is an external enlarged portion that expands toward the downstream side in the flow direction, and the external enlarged portion And the internal diameter expansion tube have substantially the same diameter expansion angle.

  An exhaust gas purification apparatus for an internal combustion engine according to a third aspect is the exhaust gas purification apparatus for an internal combustion engine according to the first aspect, wherein a plurality of the inner diameter expansion pipes are provided, and an outer diameter of the inner diameter expansion pipes is the flow. It is characterized by being smaller as it is downstream in the direction.

  The exhaust gas purification apparatus for an internal combustion engine according to claim 4 is the exhaust gas purification apparatus for an internal combustion engine according to any one of claims 1 to 3, wherein the lid member for closing the downstream end of the inlet pipe in the flow direction is provided. It is characterized by having a substantially hemispherical shape or conical shape protruding toward the downstream side in the flow direction.

  In the exhaust gas purifying apparatus according to the first aspect, the exhaust gas exhausted from the exhaust passage of the internal combustion engine flows into the upstream chamber from a large number of small holes in the inlet pipe, and an internal enlarged pipe is provided in the middle of the inlet pipe. Therefore, a part of the exhaust gas that has flowed out to the upstream part is guided to the outside by the inner and outer peripheral surfaces of the inner diameter expansion pipe and flows toward the outer peripheral side of the exhaust aftertreatment device, and the rest is exhausted along the inlet pipe It flows toward the center of the processing device.

  Accordingly, the exhaust gas flows evenly from the center to the outer peripheral side with respect to the inflow side end of the exhaust aftertreatment device, so that a uniform flow distribution can be obtained with a simple configuration in which an internal enlarged pipe is provided in the middle of the inlet pipe. As a result, the function of the exhaust aftertreatment device can be improved.

  In the exhaust gas purifying apparatus according to claim 2, since the expansion angle between the outer diameter expansion portion and the inner diameter expansion pipe is substantially the same, a flow path is formed that expands outward while maintaining the same distance therebetween. Is done. Therefore, the flow of exhaust gas becomes smooth.

  In the exhaust gas purification device according to the third aspect, the exhaust gas flowing from the inlet pipe is diffused by the plurality of internal diameter expansion pipes, so that the flow distribution can be made more uniform. In addition, since the outer diameter of the inner diameter expansion pipe is reduced as it is closer to the front end in the flow direction, the exhaust gas flowing through one inner diameter expansion pipe is not obstructed by the other inner diameter expansion pipe, As a result, the length of the inlet pipe in the flow direction can be shortened, and as a result, the outer diameter-expanded pipe can be reduced.

  In the exhaust gas purifying apparatus according to claim 4, the exhaust gas flowing from the inlet pipe is partly guided by the inner diameter expanding pipe and flows to the outer peripheral side, and a part is substantially hemispherical of the lid member. Alternatively, since it flows along the conical shape, it easily flows to the center side of the exhaust aftertreatment device. As a result, the flow of the exhaust gas becomes more uniform, and the center side of the exhaust aftertreatment device can be fully utilized. .

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

In the second and subsequent embodiments, the same reference numerals are given to the same or similar components as those described in the first embodiment, and those in the second and subsequent embodiments. The description of is simplified or omitted.
[First Embodiment]
FIG. 1 shows a first embodiment of an exhaust gas purification device 1 according to the present invention, and FIG. 2 shows components of the exhaust gas purification device 1.

  The exhaust gas purification device 1 purifies exhaust gas discharged from a diesel engine (not shown) as an internal combustion engine, and is configured such that the exhaust gas flows in a straight line from the entrance side to the exit side.

  The exhaust gas purification device 1 includes a columnar exhaust aftertreatment device 10, and the exhaust aftertreatment device 10 is accommodated in a case 20.

  The case 20 is made of sheet metal, and is provided integrally with the main body 21 on the tubular main body 21 and on the upstream side of the main body 21 (upstream in the exhaust gas flow direction; left side in FIG. 1). And an external diameter-reduced tube 23 provided integrally with the main body 21 on the downstream side of the main body 21 (downstream in the exhaust gas flow direction; right side in FIG. 1). It is configured.

  The external diameter expansion pipe 22 is expanded downstream in the flow direction, and a flange portion 22A is formed at one end of the expansion. The flange portion 22A of the outer diameter expanding pipe 22 faces the flange portion 21A of the main body portion 21 and both the portions 22A and 21A are coupled by, for example, a bolt 29. In the case 20, an upstream chamber 24 is formed by the external diameter expansion pipe 22.

  Further, the outer diameter-reduced tube 23 is formed in substantially the same shape as the outer diameter-expanded tube 22, and the main body portion 21 with the expanded portions of the outer diameter-reduced tube 22 and the outer diameter-reduced tube 23 facing each other. Are integrally provided.

  An outlet pipe 28 for discharging exhaust gas to the outside is attached to the downstream end portion of the external diameter-reduced pipe 23. In the case 20, a downstream chamber 25 is formed by the external reduced diameter tube 23.

  An intermediate portion of the inlet pipe 26 is fixed to the upstream end portion (left side in FIG. 1) of the outer diameter expanding pipe 22 by welding or the like. The inlet pipe 26 is a pipe member that communicates the exhaust passage of the diesel engine and the upstream chamber 24 in the case 20. The exhaust gas flows through the inside of the inlet pipe 26, and the downstream end of the flow is closed by a lid member 27. It has been.

  The inlet pipe 26 is inserted into the outer diameter expansion pipe 22 and enters the vicinity of the boundary between the outer diameter expansion pipe 22 and the main body 21. A large number of small holes 26 </ b> A are formed in the outer periphery of the inlet pipe 26. Note that the number, alignment, hole diameter, and the like of the small holes 26A are appropriately set according to the size of the exhaust aftertreatment device 10 and the like.

  A guide vane 30, which is an internal diameter-expanded pipe, is provided at an intermediate position in the longitudinal direction of the inlet pipe 26. The guide vane 30 is positioned substantially concentrically with respect to the outer diameter-expanded tube 22 and is formed in a cone shape that is expanded downstream of the flow. Therefore, it has a function of making the flow distribution of the exhaust gas flowing into the exhaust aftertreatment device 10 from the inlet pipe 26 uniform.

  The guide vane 30 is attached to the axis C of the inlet pipe 26 at a diameter expansion angle α2. The guide vane 30 has a diameter expansion angle α2 that is about the same as the diameter expansion angle α1 of the external diameter-reduced tube 23 by about 5 to 10 °. That is, the difference of this degree is included in the “substantially the same” range.

  The diameter expansion angle α2 and the diameter expansion angle α1 may be made completely the same, but by increasing the diameter expansion angle α2 by only about 5 to 10 ° from the diameter expansion angle α1, the exhaust gas flow path is set outside. Therefore, the guide vane 30 does not have to be long.

  If the expansion angle α2 is too smaller than the expansion angle α1, the exhaust gas diffusion effect is reduced. Conversely, if the expansion angle α2 is too large, the flow of the exhaust gas is hindered depending on the length of the guide vane 30 and the mounting position. . That is, when the guide vane 30 is provided near the center of the upstream chamber 24 and the difference between the diameter expansion angle α2 and the diameter expansion angle α1 is 5 to 10 °, the diffusion effect of the exhaust gas and the smooth flow are considered. The outer diameter D1 of the guide vane 30 is preferably 0.5 to 0.7 times the inner diameter D2 of the main body 21.

  In FIGS. 1 and 2, the flow of exhaust gas is indicated by solid arrows.

  As shown in FIG. 2, the exhaust aftertreatment device 10 has a large number of square sections or hexagonal sections (in this embodiment, a hexagonal section) communicating from the inflow side end face 11 toward the exhaust side end face 12. It consists of a carrier 14 having a flow path 13 and is arranged in the case 20 via an appropriate support member. As described in the background art, the carrier 14 is made of a ceramic made of cordierite or silicon carbide, and may be made of stainless steel depending on the application.

  When the exhaust aftertreatment device 10 is a DPF, the flow path 13 of the carrier 14 includes an inflow side flow path in which the exhaust side end face 12 side is sealed, and an exhaust side flow path in which the inflow side end face 11 side is sealed. These flow paths are arranged in a staggered manner. And the boundary wall part of each flow path is made into a random multi-hole shape, and the particulates (for example, soot) in the exhaust gas flowing in from the inflow side flow path are collected by the boundary wall part to be inflow side Clean exhaust gas that has accumulated in the flow path and from which particulates have been removed is discharged through the exhaust side flow path.

  On the other hand, when a catalyst is used in the exhaust aftertreatment device 10, a NOx reduction catalyst or a NOx occlusion reduction catalyst is supported on the carrier 14 by a known method such as impregnation by immersion, washcoat, or ion exchange. While the exhaust gas passes through the flow path 13, NOx in the exhaust gas is reduced to N2 by the action of the catalyst, and the exhaust gas is purified and cleaned.

  In the configuration provided with the guide vanes 30 described above, the exhaust gas flowing through the inlet pipe 26 flows into the upstream chamber 24 from a large number of small holes 26A, but the exhaust gas flowing from the small holes 26A upstream of the guide vanes 30 It is guided by the outer peripheral surface of the vane 30 and flows toward the outer periphery of the exhaust aftertreatment device 10 and reaches the inflow side end surface 11 of the exhaust aftertreatment device 10.

  On the other hand, a part of the exhaust gas flowing from the small hole 26 </ b> A on the downstream side of the guide vane 30 of the inlet pipe 26 is guided by the inner peripheral surface of the guide vane 30 and flows toward the center of the exhaust aftertreatment device 10.

  Further, the exhaust gas flowing out from a position near the downstream end of the inlet pipe 26 flows toward the center of the exhaust aftertreatment device 10 along the axis of the inlet pipe 26, and the inflow side end face 11 of the exhaust aftertreatment device 10. To reach.

  As described above, since the exhaust gas flows from the outer periphery, the central portion, and the central portion of the upstream chamber 24, the flow distribution is made more uniform, and flows into the exhaust aftertreatment device 10 in this uniform state.

  Then, the exhaust gas that has passed through the exhaust aftertreatment device 10 is purified by the exhaust aftertreatment device 10, and is discharged to the outside through the downstream pipe 25 through the outlet pipe 28.

According to this embodiment, there are the following effects.
(1) Exhaust gas exhausted from the exhaust passage of the internal combustion engine flows into the upstream chamber 24 from a large number of small holes 26A of the inlet pipe 26. Since the guide vane 30 is provided in the middle of the inlet pipe 26, the upstream chamber A part of the exhaust gas flowing to 24 is guided by the outer peripheral surface of the guide vane 30 and flows toward the outer periphery of the exhaust aftertreatment device 10, and a part of the exhaust gas flows along the inlet pipe 26 in the central portion of the exhaust aftertreatment device 10. It flows toward. Therefore, since the exhaust gas flows uniformly in the upstream chamber 24 toward the exhaust post-treatment device 10, a uniform flow distribution can be obtained with a simple configuration in which the guide vane 30 is provided in the middle of the inlet pipe 26. The function of the exhaust aftertreatment device 10 can be improved.
(2) Since most of the exhaust gas flowing from the many small holes 26A of the inlet pipe 26 flows toward the exhaust aftertreatment device 10, pressure loss can be reduced.
(3) The expansion angle α2 of the guide vane 30 is increased by a slight difference of about 5 to 10 ° with respect to the expansion angle α1 of the outer diameter expansion tube 22, and is substantially the same. The flow of exhaust gas becomes smooth. Moreover, since the exhaust gas passage can be expanded outward by setting the diameter expansion angle α2 to be only about 5 to 10 ° larger than the diameter expansion angle α1, the length of the guide vane 30 is not long. Good.
[Second Embodiment]
FIG. 3 shows a second embodiment of the present invention.

  The exhaust gas purifying apparatus 1 </ b> A of the present embodiment is provided with a plurality of guide vanes 40, 41, 42 in the middle of the inlet pipe 26.

  As shown in FIG. 3, a first guide vane 40, a second guide vane 41, and a third guide vane 42 are fixed at substantially equal intervals in the axial direction of the inlet pipe 26 in the middle of the inlet pipe 26. Yes. The first, second, and third guide vanes 40, 41, and 42 are smaller as the outer dimensions D1, D3, and D4 are more downstream in the exhaust gas flow direction.

  That is, the outer dimension D1 of the first guide vane 40 arranged on the most upstream side of the inlet pipe 26 is formed to be the largest, and the outer dimension D4 of the third guide vane 30 arranged on the most downstream side of the inlet pipe 26 is the largest. The outer dimension D3 of the second guide vane 41, which is formed small and disposed between the first and third guide vanes 40, 42, is formed in an intermediate size.

  The outer dimension D1 of the first guide vane 40 is substantially the same as the guide vane 30 of the first embodiment, and the diameter expansion angle α2 of the first guide vane 40 is also the guide vane of the first embodiment. 30. Further, the second and third guide vanes 41 and 42 have the same diameter expansion angle as the diameter expansion angle α2 of the first guide vane 40.

  In such a configuration, the exhaust gas flowing through the inlet pipe 26 flows into the upstream chamber 24 from the many small holes 26A, but the exhaust gas flowing from the small holes 26A upstream from the first guide vane 40 It is guided by the outer peripheral surface of the vane 40, flows toward the outer periphery of the exhaust aftertreatment device 10, and reaches the inflow side end surface 11 of the exhaust aftertreatment device 10.

  The exhaust gas flowing from the small hole 26A between the first guide vane 40 and the second guide vane 41 of the inlet pipe 26 is guided by the inner and outer peripheral surfaces of the first and second guide vanes 40, 41, and the first , Passes between the second guide vanes 40 and 41, flows somewhat toward the center of the exhaust aftertreatment device 10, and reaches the inflow side end face 11 of the exhaust aftertreatment device 10.

  The exhaust gas flowing from the small hole 26A between the third guide vane 42 and the second guide vane 41 of the inlet pipe 26 is guided by the inner and outer peripheral surfaces of the second and third guide vanes 41, 42, and these second , Passes between the third guide vanes 42 and 41, flows toward the center of the exhaust aftertreatment device 10, and reaches the inflow side end face 11 of the exhaust aftertreatment device 10.

  Further, the exhaust gas flowing from the small hole 26A downstream of the third guide vane 42 of the inlet pipe 26 flows along the inner peripheral surface of the third guide vane 42 and along the inlet pipe 26 to perform exhaust post-treatment. It goes to the center of the device 10 and reaches the inflow side end face 11 of the exhaust aftertreatment device 10.

  As described above, the exhaust gas flowing from the small hole 26A of the inlet pipe 26 flows from the outer peripheral side, the central portion, and the intermediate portion of the upstream chamber 24. Therefore, the flow distribution is made more uniform, and the exhaust gas is exhausted in this uniform state. It flows into the post-processing device 10.

  Then, the exhaust gas that has passed through the exhaust aftertreatment device 10 is purified by the exhaust aftertreatment device 10, and is discharged to the outside through the downstream pipe 25 through the outlet pipe 28.

In this embodiment, in addition to the same effects as the above (1) to (3), there are the following effects.
(4) Since the exhaust gas flowing from the inlet pipe 26 flows while being guided by the first, second, and third guide vanes 40, 41, and 42, the flow distribution can be made more uniform.
(5) Since the outer diameters of the first, second, and third guide vanes 40, 41, and 42 are made smaller as they are downstream in the flow direction, the exhaust gas flowing through one guide vane 40 and the like As a result, the length of the inlet pipe 26 can be shortened, and as a result, the outer diameter-expanded pipe 22 can be made smaller.
[Third Embodiment]
FIG. 4 shows a third embodiment of the present invention.

  In the exhaust gas purification apparatus 1B of this embodiment, the lid member 47 that closes the downstream end of the inlet pipe (26) in the flow direction has a substantially hemispherical shape protruding toward the downstream side in the flow direction.

  In such a configuration, the exhaust gas flowing through the inlet pipe 26 flows from the small holes 26 </ b> A to the upstream chamber 24, but the exhaust gas flowing from the small holes 26 </ b> A upstream from the guide vane 30 is outside the guide vane 30. It is guided by the surface and flows toward the outer periphery of the exhaust aftertreatment device 10 and reaches the inflow side end face 11 of the exhaust aftertreatment device 10.

  On the other hand, a part of the exhaust gas flowing from the small hole 26 </ b> A on the downstream side of the guide vane 30 of the inlet pipe 26 is along the inner peripheral surface of the guide vane 30, and a part is along the surface of the lid member 47 from the inlet pipe 26. It flows toward the center of the exhaust aftertreatment device 10 and reaches the inflow side end face 11 of the exhaust aftertreatment device 10.

In this embodiment, in addition to the same effects as the above (1) to (3), there are the following effects.
(6) A part of the exhaust gas flowing from the inlet pipe 26 is guided by the outer peripheral surface of the guide vane 30 and flows toward the outer periphery of the exhaust aftertreatment device 10, and a part thereof is formed in a substantially hemispherical shape. Since the exhaust gas flows toward the center of the exhaust aftertreatment device 10 along the surface of the hemispherical portion of the lid member 47, the exhaust gas is made uniform, and the center of the exhaust aftertreatment device 10 can be fully utilized. The purification efficiency is further improved.

  Note that the present invention is not limited to the above-described embodiments, and includes other configurations that can achieve the object of the present invention, and includes the following modifications and the like.

  That is, in the second embodiment, the lid member 27 of the inlet pipe 26 provided with the first guide vane 40, the second guide vane 41, and the third guide vane 42 is formed in a plate shape. Instead of the lid member 27, the substantially hemispherical lid member 47 of the third embodiment may be used.

  In this way, the exhaust gas is made to flow uniformly by the first, second, and third guide vanes 40, 41, and 42, and flows along the surface of the hemispherical lid member 47. Since it flows toward the center of the processing apparatus 10, the exhaust gas flows more uniformly.

  Moreover, in the said 3rd Embodiment, what formed the cover member 47 of the inlet pipe 26 in the substantially hemispherical shape was used, However, It is not restricted to this, For example, you may form in a cone shape.

  And even if it does in this way, the effect similar to the effect of the said 3rd Embodiment can be acquired.

  In addition, the overall shape of the carrier 14 constituting the exhaust aftertreatment device 10, the overall shape of the case 20, the external diameter expansion pipe 22 and the external diameter reduction pipe 23, the shape of the inlet pipe 26, and their materials are The embodiment can be changed as appropriate, and is not limited to the above-described embodiments.

  INDUSTRIAL APPLICABILITY The present invention can be used as an exhaust gas purifying device for diesel engines, and as an exhaust gas purifying device for any internal combustion engine in which an exhaust aftertreatment device is expected to be applied.

It is sectional drawing which shows 1st Embodiment of the exhaust-gas purification apparatus which concerns on this invention. It is a perspective view which shows the structural member of the said 1st Embodiment. It is sectional drawing which shows 2nd Embodiment of the exhaust-gas purification apparatus which concerns on this invention. It is sectional drawing which shows 3rd Embodiment of the exhaust-gas purification apparatus which concerns on this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,1A, 1B ... Exhaust gas purification apparatus, 10 ... Exhaust after-treatment apparatus, 20 ... Case, 22 ... External diameter expansion pipe part which forms upstream chamber, 24 ... Upstream chamber, 26 ... Inlet pipe, 26A ... Many small holes , 27, 47 ... lid member, 30 ... guide vane which is an inner diameter-expanded pipe, [alpha] 1 ... diameter-expansion angle of the outer diameter-expanded pipe section, [alpha] 2 ... diameter-expansion angle of the guide vane

Claims (4)

In an exhaust gas purification device for an internal combustion engine provided in an exhaust passage of the internal combustion engine and provided with an exhaust aftertreatment device,
A case (20) containing the exhaust aftertreatment device (10);
Said case (20) upstream chamber provided upstream of an exhaust gas flow direction with respect to the (24),
To together the exhaust gas provided in the upstream chamber (24) flows, is closed downstream end of the flow direction of the exhaust gas, and an inlet pipe having a large number of small holes on the outer periphery (26),
An inner diameter expansion pipe (30) that expands from the outer periphery of the midway position in the longitudinal direction of the inlet pipe (26) toward the downstream side in the exhaust gas flow direction ;
An exhaust gas purifying device for an internal combustion engine, wherein exhaust gas flowing simultaneously on both sides of the inner and outer peripheral surfaces forming the expanded portion of the inner expanded pipe (30) flows into the exhaust aftertreatment device (10). 1).
The exhaust gas purification device (1) for an internal combustion engine according to claim 1,
The portion forming the upstream chamber (24) of the case (20) is an external diameter-expanded portion that expands toward the downstream side in the flow direction,
An exhaust gas purifying device (1) for an internal combustion engine, characterized in that an expansion angle between the external expansion portion (22) and the internal expansion tube (30) is substantially the same. The exhaust gas purification device (1) for an internal combustion engine according to claim 1,
A plurality of the inner diameter-expanded tubes (40), (41), (42) are provided, and the outer diameters of these inner diameter-expanded tubes (40), (41), (42) are on the downstream side in the flow direction. An exhaust gas purification device (1A) for an internal combustion engine, characterized by being so small. The exhaust gas purification device (1) for an internal combustion engine according to any one of claims 1 to 3,
The lid member (47) for closing the downstream end in the flow direction of the inlet pipe (26) has a substantially hemispherical shape or a conical shape protruding toward the downstream side in the flow direction. Exhaust gas purification device (1B).

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