JP2014015848A - Exhaust emission control device of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exhaust emission control device of a vehicle which has low exhaust resistance, smoothly and readily treats exhaust, and prevents a catalyst from damaging or the like.SOLUTION: An exhaust emission control device of a vehicle includes: an exhaust pipe for allowing exhaust discharged from an internal combustion engine to flow; an oxidation catalyst in which unburnt components contained in the exhaust are subjected to an oxidation treatment; a particulate capturing filter provided downstream of the oxidation catalyst in the exhaust direction and for capturing particulates in the exhaust; a DPF container for housing the oxidation catalyst and the particulate capturing filter; an opening connection provided between the exhaust pipe and the DPF container and in which a cross-sectional area breaking on the vertical surface in the exhaust direction increases with the distance from the exhaust pipe to the DPF container; and a fin member provided inside the opening connection and in which a blade inclining in the exhaust direction stirs exhaust passing through the opening connection.

Description

  The present invention relates to an exhaust emission control device for a vehicle provided with fins in an exhaust pipe line.

  An internal combustion engine of a vehicle is provided with an exhaust purification device that purifies exhaust. For example, a diesel engine includes an exhaust gas purification device including an oxidation catalyst, a DPF (Diesel Particulate filter), a nitrogen oxide (NOx) reduction device of a urea SCR (Selective Catalytic Reduction) system, and the like.

  The oxidation catalyst oxidizes carbon monoxide, hydrocarbons and the like contained in the exhaust gas, and changes them into carbon dioxide and water. The oxidation catalyst oxidizes NO, which is NOx, and changes it to NO2 (nitrogen dioxide). A DPF (Diesel Particulate filter) has a large number of minute holes and captures fine particles (also called PM) such as soot contained in exhaust gas. In order to eliminate clogging, the DPF performs a regeneration process in which captured fine particles are combusted as appropriate.

  The regeneration process of the DPF is performed by supplying, for example, a fuel component to the oxidation catalyst disposed on the upstream side of the DPF. The supplied fuel component undergoes an oxidation reaction with an oxidation catalyst, and the exhaust gas is heated to a high temperature by reaction heat. The exhaust gas that has reached a high temperature is sent to the DPF, and the fine particles trapped in the DPF are heated and burned.

  The nitrogen oxide (NOx) reduction device of the urea SCR system adds urea water to the exhaust gas, and reduces NOx contained in the exhaust gas with a NOx reduction catalyst to form nitrogen and water. In the urea SCR system, NO2 is easier to reduce with urea water (ammonia) than NO. Therefore, the exhaust purification device oxidizes most of NO contained in the exhaust to NO 2 with an oxidation catalyst.

  Normally, in an exhaust purification device, a DPF processing device including an oxidation catalyst and a DPF has a larger cross-sectional area than an exhaust pipe extending from an engine. For this reason, an expansion connection pipe having a gradually increased cross-sectional area is attached between the exhaust pipe and the DPF processing apparatus, or a punching metal is provided in front of the catalyst, and the exhaust gas is dispersed and introduced into the catalyst. In addition, in the exhaust purification device of the urea SCR system, an invention is known in which fins are provided in the exhaust pipe so that urea water sprayed in the exhaust pipe is diffused into the exhaust.

JP 2007-162487 A

  However, when the speed of the exhaust flow in the exhaust pipe is increased, the exhaust gas may pass through the inside of the expanded connection pipe without almost expanding from the thickness of the exhaust pipe, and may flow into the DPF processing apparatus.

  Thus, if the exhaust gas flows into the oxidation catalyst without spreading, the exhaust gas concentrates on a part of the catalyst, and when the DPF is regenerated, many fuel components are supplied to the location where the exhaust gas is concentrated. Then, a part of the catalyst becomes hot due to the oxidation reaction of the fuel component, and the catalyst may be damaged. On the other hand, at a place where the flow rate of the exhaust gas is low, the temperature does not rise sufficiently, and the temperature control of the exhaust gas may cause a problem. There is.

  In addition, the exhaust gas that has passed through the oxidation catalyst flows in a partly part of the DPF provided behind the oxidation catalyst, so that the clogging of a part of the DPF is accelerated or a part of the DPF is regenerated. There is a possibility that the temperature of the DPF becomes high and the deterioration of the DPF is accelerated.

  Further, when the punching metal is provided to widely disperse the exhaust gas, the flow resistance is increased by reducing the holes of the punching metal. Therefore, there is a risk of reducing the fuel consumption of the vehicle. Furthermore, even when urea water is dispersed with fins provided in the exhaust pipe, there is a possibility that the flow resistance of the exhaust purification device is increased and the fuel consumption of the vehicle is lowered.

  An object of the present invention is to solve the above-mentioned problems, and to provide an exhaust emission control device for a vehicle that has low flow resistance, smoothly and reliably treats exhaust gas, and does not cause damage to the catalyst. .

  The vehicle exhaust gas purification apparatus of the present invention is configured as follows. An exhaust pipe that distributes the exhaust discharged from the internal combustion engine, an oxidation catalyst that oxidizes unburned components contained in the exhaust in the exhaust pipe, and a downstream of the oxidation catalyst in the exhaust direction. A fine particle capturing filter to be captured, a DPF container body connected to the exhaust pipe and containing the oxidation catalyst and the fine particle capturing filter, and a cross section broken between the exhaust pipe and the DPF container body and cut in a plane perpendicular to the exhaust direction. Of the widened connection portion that increases as it advances from the exhaust pipe to the DPF container body, and the blade that is provided inside the widened connection portion and inclined with respect to the exhaust direction. And a fin member that stirs the exhaust gas passing through.

  According to the exhaust emission control device of the present invention, exhaust gas flows from the engine into the DPF container in a uniform state. As a result, there is no variation in partial clogging or temperature distribution, the oxidation catalyst, the particulate trapping filter, and the nitrogen oxide reduction device can function sufficiently, and damage due to partial overheating can be effectively prevented. .

1 is an exploded perspective view showing an exhaust emission control device for a vehicle according to an embodiment of the present invention. The perspective perspective view which shows the flow of the exhaust_gas | exhaustion in the same exhaust gas purification apparatus. The perspective view which shows a fin member. The front view which shows a fin member. The graph which shows the relationship between the area ratio which the blade | wing occupies in the whole fin member, a pressure loss, and the uniformity of the flow velocity distribution of exhaust. The block diagram which shows the whole internal combustion engine provided with the exhaust gas purification device.

  An exhaust emission control device for a vehicle according to an embodiment of the present invention will be described. FIG. 1 is an exploded perspective view showing the entire exhaust emission control device 10, FIG. 2 is a perspective view showing the flow of exhaust gas in the exhaust emission control device 10, and FIG. 3 is a perspective view showing the fin member 36. FIG. 4 is a front view showing the fin member 36, and FIG. 5 shows the relationship between the area ratio of the blades 44 in the entire area of the fin member 36, the pressure loss, and the uniformity of the flow velocity distribution of the exhaust gas. FIG. 6 is a configuration diagram showing the entire engine 50 including the exhaust purification device 10.

  As shown in FIG. 1, the exhaust purification device 10 includes an exhaust pipe 26 extending from the engine 50, a DPF processing device 12 connected to the exhaust pipe 26, and a urea SCR (Selective Catalytic) connected to the DPF processing device 12. And a NOx purification device 14 of a system called “Reduction”.

  As shown in FIG. 6, the exhaust purification device 10 is connected to an engine 50 of the vehicle via an exhaust pipe 26. Hereinafter, the exhaust emission control device 10 is referred to as upstream-downstream side or front-rear side with reference to the flow direction E of exhaust gas in the exhaust pipe 26 (see FIG. 3).

  An engine 50 shown in FIG. 6 is a diesel engine and is mounted on a vehicle. The engine 50 includes an exhaust pipe 26 connected to an exhaust port 51 of the engine 50, a supercharger (turbocharger) 52, a fuel injection device 54, an intercooler 56, an intake pipe 28, and the exhaust purification device 10. And a control device 62 and the like.

  An exhaust pipe 26 from the engine 50 and an intake pipe 28 from the air cleaner 58 are connected to the supercharger 52. The supercharger 52 rotates the exhaust turbine with the exhaust from the exhaust pipe 26 and pressurizes the outside air sucked through the air cleaner 58 by the rotation of the compression turbine. The outside air pressurized by the supercharger 52 is cooled through the intercooler 56 and sent from the intake port 53 into the combustion chamber of the engine 50.

  The exhaust gas discharged from the engine 50 is rotated by the supercharger 52 and then sent to the exhaust gas purification device 10 through the exhaust pipe 26 and purified. The engine 50 is not limited to a diesel engine, and may be a naturally aspirated engine in which the supercharger 52 is not provided.

  In the exhaust purification apparatus 10, the exhaust pipe 26 from the supercharger 52 is connected to the upstream side, and the exhaust port 60 is in communication with the downstream side. Inside the DPF processing device 12, an oxidation catalyst 16 and a DPF 18 as a particulate trapping filter are provided along the exhaust flow direction E.

  The oxidation catalyst 16 oxidizes carbon monoxide, hydrocarbons, NOx and the like contained in the exhaust gas, and changes them into carbon dioxide, water, and nitrogen dioxide. The DPF 18 is provided downstream of the oxidation catalyst 16. The DPF 18 is made of a ceramic material having substantially the same diameter as the oxidation catalyst 16 and formed with fine pores. The DPF 18 filters exhaust gas treated by the oxidation catalyst 16, and includes PM (Particulate Matter) contained in the exhaust gas. Captures the fine particle components (mainly apportioned).

  The NOx purification device 14 includes a urea water injection mechanism, a NOx reduction catalyst 22, and an ammonia decomposition catalyst 24. The urea water injection mechanism includes a urea water injection valve 30, a storage tank that stores urea water, a delivery pump that sends out urea water, a pump drive mechanism (all not shown), and the like. The urea water injection valve 30 is provided between the DPF processing device 12 and the NOx reduction catalyst 22. The urea water injection valve 30 ejects urea water into the exhaust pipe 26 by driving a delivery pump of the urea water injection mechanism.

  The NOx reduction catalyst 22 and the ammonia decomposition catalyst 24 are accommodated in the same container body 38. The NOx reduction catalyst 22 is a selective reduction catalyst, and selectively reduces NOx using ammonia converted from urea water as a reducing agent to change it into nitrogen and water that are harmless to the human body. The ammonia decomposition catalyst 24 oxidizes and decomposes the ammonia slipped by the NOx reduction catalyst 22 to change it into nitrogen and water.

  In addition, the DPF processing device 12 is connected to the exhaust pipe 26 through an expanded connection pipe 20 as an expanded connection section. The open-spread connecting pipe 20 has a funnel shape, and its inner diameter expands almost linearly from an inlet 32 having the same diameter as the outlet pipe 26 to an outlet 34 connected to the inlet of the DPF processing device 12. .

  As shown in FIG. 1, a fin member 36 is attached to the inside of the spread connection pipe 20. The fin member 36 is attached in the vicinity of the inlet 32 of the spread-out connecting pipe 20. As shown in FIGS. 3 and 4, the fin member 36 includes an outer frame body 40, a cylindrical base 42, and a blade 44 attached around the base 42.

  The outer frame body 40 is a flat annular body, and has an outer shape equivalent to the outer shape of the attachment position of the spread expansion connecting pipe 20 to which the fin member 36 is attached. The base 42 has a cylindrical shape, and is attached to the center portion of the outer frame body 40 substantially coaxially with the outer frame body 40.

  Eight blades 44 are provided at equal positions between the outer frame body 40 and the base 42. The blades 44 are curved with respect to the exhaust direction E. The blades 44 are provided such that when the exhaust gas passes through the fin member 36 along the exhaust direction E, the exhaust gas rotates around the central axis A of the fin member 36. FIG. 2 shows the state of the exhaust flow from the exhaust pipe 26 to the exhaust purification device 12.

  Specifically, as shown in FIG. 3, the blade 44 has an upstream end in the exhaust direction E, that is, an end on the engine 50 side, oriented in a direction substantially parallel to the central axis A of the exhaust pipe 26. Yes. The blades 44 are gradually curved from the upstream edge, and the direction is set at a predetermined angle at the edge on the side where the exhaust gas flows out from the fin member 36. Further, as shown in FIG. 4, the blade 44 has an area ratio of about 40% with respect to the entire area of the fin member 36 when the fin member 36 is viewed from the direction along the central axis A.

  The control device 62 is connected to various sensors and operates the fuel injection device 54 and others to drive the engine 50. Further, the control device 62 injects a predetermined amount of urea water into the exhaust pipe 26 from the urea water injection valve 30 in order to process NOx in the exhaust gas.

  Further, for example, when the control device 62 detects a pressure loss in the exhaust purification device 10 from sensors or the like provided before and after the exhaust purification device 10 and determines that the pressure loss of the exhaust purification device 10 exceeds a predetermined value, the DPF 18 Perform the playback process. When the control device 62 determines the regeneration process, the control device 62 causes the fuel injection device 54 to inject more fuel than the fuel required for vehicle travel and idling. The excessively injected fuel is oxidized by the oxidation catalyst 16 to raise the exhaust gas temperature. The control device 62 raises the temperature of the exhaust gas to a temperature at which soot accumulated in the DPF 18 burns, and burns PM (soot particulates) in the exhaust to regenerate the DPF 18.

  Next, the operation and effect of the exhaust emission control device 10 will be described. Exhaust gas discharged from the engine 50 flows into the exhaust pipe 26, passes through the supercharger 52, and flows into the exhaust purification device 10. Exhaust gas flows from the exhaust pipe 26 into the DPF processing device 12 through the spread connecting pipe 20.

  Exhaust gas flowing into the DPF treatment device 12 is oxidized by an oxidation catalyst 16 in the unburned components contained in the exhaust gas. Then, the exhaust gas is filtered by the DPF 18, fine particles including carbon components contained in the exhaust gas are captured, and flow into the NOx reduction catalyst device 14 from the DPF processing device 12.

  When the exhaust gas flows into the NOx reduction catalyst device 14, urea water is injected from the urea water injection valve 30 into the exhaust gas. The urea water urea turns into ammonia, and the NOx reduction catalyst 22 reduces the NOx contained in the exhaust gas to change it into nitrogen and water. Further, the ammonia slipped on the NOx reduction catalyst 22 is oxidized and decomposed by the ammonia decomposition catalyst 24 and changed into nitrogen and water. In this way, the exhaust from the engine 50 is purified and exhausted from the exhaust port 60 to the atmosphere.

  The exhaust gas purification device 10 is an expanded connection pipe 20 having a fin member 36, and connects the exhaust pipe 26 and the DPF processing device 12. Therefore, when the exhaust gas flows into the DPF processing apparatus 12, the exhaust gas that receives the swirling action from the blades 44 and that flows into the widening connection pipe 20 from the exhaust pipe 26 as a flow path indicated by a dotted line in FIG. Is done.

  Since the fin member 36 is provided in the vicinity of the inlet 32 of the spread connecting pipe 20, that is, on the exhaust upstream side of the spread connecting pipe 20, as shown in FIG. A swirling action is received from the blades 44 of the member 36. As a result, the exhaust gas is sufficiently agitated by the fin member 36, and the flow velocity is made uniform.

  Then, the exhaust gas flows into the oxidation catalyst 16 of the DPF processing device 12 evenly while gradually spreading in the widened connection pipe 20 along with the spread of the widened connection pipe 20. As described above, the exhaust gas flows into the oxidation catalyst 16 in an approximately equal amount along the inflow side end surface of the oxidation catalyst 16, so that the oxidation reaction of the exhaust gas is performed uniformly along the inflow surface in the oxidation catalyst 16.

  As a result, an equal amount of exhaust gas also flows into the DPF 18 provided behind the oxidation catalyst 16 along a cross section perpendicular to the flow direction of the exhaust gas. Therefore, the fine particles contained in the exhaust are captured almost uniformly by the DPF 18 along a cross section perpendicular to the exhaust flow direction. Therefore, the DPF 18 does not cause partial clogging, and the usable time of the DPF 18, that is, the time interval until the next regeneration process can be increased.

  When the particulate matter captured by the DPF 18 reaches a predetermined amount and the control device 62 determines that the regeneration process of the DPF 18 is performed based on the value of the sensor or the like, the control device 62 determines the fuel required for running or idling the vehicle. More fuel is injected from the fuel injector 54. The excessively injected fuel is not burned in the cylinder of the engine 50 and is discharged to the exhaust pipe 26 together with the exhaust gas as an unburned component.

  As described above, the exhaust gas containing excess unburned components flows into the oxidation catalyst 16 substantially evenly along the inflow surface, so that the unburned components contained in the exhaust gas are evenly processed by the oxidation catalyst 16. As a result, the high-concentration unburned fuel component does not partially flow into the oxidation catalyst 16, and the reaction temperature in the oxidation catalyst 16 can be made uniform in the vertical plane in the exhaust flow direction.

  Then, the exhaust gas whose temperature has increased due to the oxidation reaction at the oxidation catalyst 16 flows into the DPF 18. Since the exhaust gas has almost the same temperature difference depending on the place and has almost the same temperature, the temperature of the DPF 18 rises evenly along a cross section perpendicular to the flow direction of the exhaust gas. Thereby, in the DPF 18, the particulate component captured by the DPF 18 can be burned almost uniformly.

  Furthermore, particulate components are uniformly captured in the DPF 18 along a cross section perpendicular to the flow direction of the exhaust, and exhaust gas having a uniform temperature flows along the cross section perpendicular to the flow direction of the exhaust. As a result, the fine particle component rises uniformly to the combustion temperature. Therefore, the DPF 18 can reliably and efficiently burn the captured fine particle component in a stable state.

  Further, the fin member 36 includes a base 42 in the center, thereby providing a space, so that a large flow resistance does not occur in the exhaust pipe 26 and the widening connection pipe 20, and the exhaust from the exhaust pipe 26 is DPF. It is possible to smoothly flow into the processing device 12 and prevent deterioration of fuel consumption. Further, in the exhaust purification device 10, since the exhaust pipe 26 and the spread-out connecting pipe 20 are not arranged in the same straight line, the exhaust abuts against the side surface of the base 42 from an oblique direction, thereby the exhaust flow. The path is changed, and the flow rate and temperature of the exhaust gas can be made more uniform along the cross section by the diffusion action of the base 42.

  The urea water is injected from the urea water injection valve 30 into the exhaust gas that has passed through the DPF processing device 12 and mixed with the urea water. The exhaust gas mixed with urea water flows into the NOx reduction catalyst 22. Urea of urea water turns into ammonia. The exhaust gas is appropriately processed by the DPF processing device 12, and the exhaust gas temperature and NOx are also set within the range of assumed values.

  Therefore, in the NOx reduction catalyst 22, the exhaust gas to which urea is added reacts with NOx and ammonia contained in the exhaust gas, and changes into nitrogen and water, thereby detoxifying NOx harmful to the human body. Since a large amount of nitric oxide contained in the exhaust gas is oxidized into nitrogen dioxide by the catalytic reaction in the oxidation catalyst 16, NOx can be efficiently converted into nitrogen and water in the NOx reduction catalyst 22. Ammonia slipped on the NOx reduction catalyst 22 is oxidized and decomposed by the ammonia decomposition catalyst 24 and changed into nitrogen, water, and the like.

  Since an appropriate amount of urea water is injected from the urea water injection valve 30 to the exhaust gas, there is little excess or deficiency in the injection amount of urea water, and NOx remaining without being processed in the NOx reduction catalyst 22 or NOx reduction catalyst The amount of ammonia slipping without being consumed at 22 can also be reduced.

  FIG. 5 shows the relationship between the area ratio of the blades 44 to the entire fin member 36, the flow resistance of the fin member 36, and the uniform index UI (UI: Uniformity Index: γ) (hereinafter referred to as “UI”) of the flow velocity distribution of the exhaust. Experimental results are shown. The horizontal axis of FIG. 5 shows the area ratio of the blades 44 to the total area of the fin member 36 as viewed from the exhaust flow direction in%, the left vertical axis shows the UI of the exhaust in the oxidation catalyst 16, The right vertical axis represents the flow resistance of the fin member 36.

The exhaust UI (γ) is obtained by the following equation.

  S is the opening area of the measurement location (front surface of the oxidation catalyst 16), Si is the area at each measurement point, va is the average flow velocity value, and vi is the flow velocity at the measurement point. The exhaust UI is theoretically 1 in which the flow velocity distribution is completely uniform, and at this time, the flow rate is also uniform with respect to the opening surface.

  The experiment was performed under the following conditions. The fin member 36 has an outer diameter of the outer frame 40 of 77 mm, a diameter of the base 42 of 30 mm, a depth of the outer frame 40 of 20 mm, and eight blades 44 between the outer frame 40 and the base 42. It is provided in between. The area ratio of the blades 44 of the entire area of the fin member 36 was changed by changing the angle of the blades 44 with respect to the central axis of the fin member 36. The entire area of the fin member 36 is the entire area inside the outer frame body 40.

  According to the graph of FIG. 5, it can be seen that when the area ratio of the entire area of the fin member 36 occupied by the blades 44 is 25% or less, the UI of the exhaust gas greatly decreases. Further, it can be seen that when the area ratio of the entire area of the fin member 36 occupied by the blades 44 is 45% or more, the flow resistance increases and the UI of the exhaust gas decreases.

  As a result, when the area ratio of the entire area of the fin member 36 occupied by the blades 44 is between about 25% and about 45%, both the flow resistance and the UI can be excellent in the fin member 36. Recognize.

  As described above, according to the vehicle exhaust purification device 10 of the present embodiment, the exhaust gas flows evenly and uniformly from the exhaust pipe 26 to the oxidation catalyst 16 of the DPF processing device 12. Since the exhaust gas uniformly flows into the oxidation catalyst 16, the reaction in the oxidation catalyst 16 is performed uniformly, and a part of the exhaust gas does not reach a high temperature, and the durability of the catalyst can be improved. Since the value of the maximum processing capacity required for the oxidation catalyst 16 can be lowered, the oxidation catalyst 16 can be reduced in size.

  Since the exhaust gas uniformly flows from the oxidation catalyst 16 into the DPF 18, the particulate component in the exhaust gas is captured by the DPF 18 evenly along the cross section of the DPF 18. In this way, since the fine particles are evenly captured, clogging does not occur at an early stage in a part of the DPF 18, and the interval of the regeneration process of the DPF 18 can be extended. During regeneration, a large amount of the particulate component does not burn in a part of the DPF 18, so that the temperature rise becomes uniform and the durability of the DPF 18 can be improved.

  Since the exhaust gas is appropriately purified by the DPF treatment device 12, the NOx reduction catalyst device 14 can also appropriately reduce NOx, reduce the release of NOx to the atmosphere as much as possible, and waste of urea water. Unnecessary consumption can be suppressed. Since the area ratio of the blades 44 to the entire area of the fin member 36 is between about 25% and about 45%, the flow resistance in the fin member 36 is small, the fuel consumption of the vehicle can be improved, and the exhaust The UI can be improved, and exhaust can be reliably processed. Since the fin member 36 is provided on the upstream side of the intermediate point along the exhaust direction of the spread connecting pipe 20, the uniform flow velocity by the fin member 36 can be more effectively realized. Since the base 42 is provided to be inclined with respect to the flow direction of the exhaust gas, it is possible to promote the uniform flow velocity without increasing the flow resistance so much.

  The exhaust emission control device of the present invention is not limited to the above embodiment. For example, the fin member 36 may be provided at an arbitrary position of the spread connecting pipe 20. Further, the shape, the number, and the angle of the blades 44 of the fin member 36 are not limited to the shape of the above-described embodiment.

  In addition, although the blades 44 are provided outside the base 42 installed in the center of the fin member 36, the fin members are provided with blades inside the base 42, and the space between the base 42 and the outer frame body 40 is between. Further, a configuration in which a support piece or the like for supporting the base 42 is provided and no blade is provided may be employed. In the case of this fin member, the exhaust spreads outward from the central portion, and the exhaust can be easily diffused. Further, the blades 44 may be arranged from the center of the fin member 36 without setting the base 42 at the center of the fin member 36. The NOx reduction treatment method according to the present invention is not limited to the above example, and may be another treatment method.

  As mentioned above, although embodiment of this invention was described, the said embodiment is shown as an example and is not intending limiting the range of invention. The novel embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. This embodiment and its modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  The present invention is used in an exhaust emission control device for a vehicle.

  DESCRIPTION OF SYMBOLS 10 ... Exhaust gas purification apparatus, 12 ... DPF processing apparatus, 14 ... NOx reduction catalyst apparatus, 18 ... DPF, 20 ... Opening expansion pipe, 22 ... NOx reduction catalyst, 24 ... Ammonia decomposition catalyst, 26 ... Exhaust pipe, 28 ... Intake Pipe, 30 ... Urea water injection valve, 32 ... Inlet, 34 ... Outlet, 36 ... Fin member, 38 ... Container body, 40 ... Outer frame body, 42 ... Base, 44 ... Blade, 50 ... Engine, 60 ... Discharge port, 62 ... control device, A ... center axis, E ... exhaust direction.

Claims (5)

An exhaust pipe connected to the internal combustion engine for circulating the exhaust discharged from the internal combustion engine;
An oxidation catalyst for oxidizing unburned components contained in the exhaust in the exhaust pipe;
A particulate trapping filter that is provided downstream of the oxidation catalyst in the exhaust direction, filters the exhaust, and traps particulates contained in the exhaust;
A DPF container coupled to the exhaust pipe and containing the oxidation catalyst and the particulate trapping filter;
An open connection part provided between the exhaust pipe and the DPF container body, and an area of a cross-section broken at a plane perpendicular to the exhaust direction increases from the exhaust pipe to the DPF container body;
A fin member that is provided on the inner side of the spread connection portion and stirs the exhaust gas that passes through the spread connection portion by means of blades that are inclined with respect to the exhaust direction;
An exhaust emission control device for a vehicle, comprising:   2. The SCR reduction device according to claim 1, further comprising an SCR reduction device that supplies urea water into the exhaust gas downstream of the particulate trapping filter to selectively reduce NOx contained in the exhaust gas. An exhaust emission control device for a vehicle as described in 1.   The blades are continuously curved and the ratio of the area of the blades to the entire area of the fin member perpendicular to the exhaust direction is 25% or more and 45% or less. The exhaust emission control device for a vehicle according to claim 1 or 2.   The fin member includes an outer frame body, a base provided on the inner side of the outer frame body, and a blade provided between the outer frame body and the base. The exhaust purification device for a vehicle according to any one of claims 1 to 3, wherein the exhaust purification device for a vehicle according to any one of claims 1 to 3, wherein the exhaust purification device is provided upstream of an intermediate point along the exhaust direction.   The exhaust pipe is connected in a positional relationship other than parallel with the spread connection pipe, the center line of the exhaust pipe and the center line of the spread connection pipe, and the fin member is connected to the spread connection pipe, 5. The exhaust emission control device for a vehicle according to claim 4, wherein the center line and the center of the spread-out connecting pipe are attached in parallel.

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