Aftertreatment system

Abstract

To provide an aftertreatment system enabling sharing of a component.SOLUTION: An aftertreatment system includes: a cylindrical first treatment part extending in a first cylinder axial direction to treat exhaust gas discharged from an internal combustion engine; and a cylindrical second treatment part disposed on an exhaust gas downstream side of the first treatment part and extending in a second cylinder axial direction to treat exhaust gas. The aftertreatment system also includes: a first pipe extending in a direction that forms a first angle with respect to the first cylinder axial direction and disposed rotatably about the first cylinder axial direction to derive exhaust gas treated by the first treatment part; a second pipe extending in a direction that forms a second angle with respect to the second cylinder axial direction and disposed rotatably about the second cylinder axial direction to derive exhaust gas treated by the second treatment part; and a third pipe formed to have an angle obtained by adding the first angle and the second angle and coupling the first pipe and the second pipe.SELECTED DRAWING: Figure 11

Description

[Technical Field]

[0001] The present disclosure relates to aftertreatment systems. [Background technology]

[0002] Conventionally, particulate matter (PM) is contained in exhaust gas emitted from internal combustion engines. PM is generated when the air-fuel ratio becomes rich, exceeding 1.5 times the stoichiometric air-fuel ratio. On the other hand, PM decreases when the air-fuel ratio becomes lean, falling below 1.5 times the stoichiometric air-fuel ratio. In the case of diesel engines, when the air-fuel ratio becomes rich, exceeding twice the stoichiometric air-fuel ratio, there is a lack of oxygen, resulting in the generation of PM. However, when the air-fuel ratio approaches the stoichiometric air-fuel ratio or becomes leaner, the combustion temperature rises, generating nitrogen oxides (NOx), creating a trade-off.

[0003] Vehicles are equipped with aftertreatment systems that process PM and NOx in exhaust gases. Known exhaust treatment devices for PM include diesel particulate filters (DPFs), which capture and remove PM. Another known device is a diesel oxidation catalyst (DOC), which heats the exhaust gas by oxidizing the fuel (HC) injected after the combustion process, thereby promoting combustion within the DPF. Another known exhaust treatment device for NOx is a selective catalytic reduction (SCR), which mixes a reducing agent such as ammonia with exhaust gas containing NOx and breaks the NOx down into nitrogen and water.

[0004] The layout of the aftertreatment system, which consists of DPF, DOC, SCR, etc., is set according to the vehicle model.

[0005] For example, Patent Document 1 discloses an aftertreatment system that is provided downstream of an aftertreatment device that purifies exhaust gas emitted from an internal combustion engine mounted on a vehicle, and that includes a tubular body having an internal flow path for the exhaust gas purified by the aftertreatment device, the tubular body having a curved portion that is curved so as to be convex upward in the height direction of the vehicle.

[0006] Furthermore, for example, Patent Document 2 discloses an exhaust purification system in which an exhaust system includes an after-treatment device that purifies exhaust gas by passing it through, and in which a layout is adopted in which exhaust gas is introduced into this after-treatment device in a reversed manner. The after-treatment system includes a gas dispersion chamber that surrounds the inlet end face of the after-treatment device and introduces exhaust gas through an exhaust inlet from a direction approximately perpendicular to the axial direction of the after-treatment device, and an exhaust pipe that introduces exhaust gas to the exhaust inlet of the gas dispersion chamber extends in the axial direction of the after-treatment device and is temporarily bent away from the exhaust inlet just before the exhaust inlet, then bent back in a hook shape to connect to the exhaust inlet, and an air guide structure is provided in the gas dispersion chamber so that the flow of exhaust gas can be bent in an arc toward the axial center of the after-treatment device in cooperation with the hook-shaped exhaust guide portion of the exhaust pipe.

[0007] Furthermore, for example, Patent Document 3 discloses an aftertreatment system having an exhaust pipe through which exhaust gas emitted from an internal combustion engine mounted on a vehicle flows, and a terminal portion that is arranged below the vehicle and downstream of the exhaust pipe and discharges the exhaust gas from the right or left side of the vehicle toward the left or right side of the vehicle, and having an aftertreatment device that is arranged downstream of the exhaust pipe and upstream of the terminal portion and purifies the exhaust gas. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2020-148146 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-104393 [Patent Document 3] Japanese Patent Publication No. 2020-51408 Summary of the Invention [Problem to be solved by the invention]

[0009] The layout of the multiple components that make up the aftertreatment system is set according to the vehicle model, and generally, the shape, size, etc. of each of the multiple components are changed in response to layout variations.

[0010] The post-processing systems described in each of Patent Documents 1 to 3 also have the problem that it is difficult to standardize parts because parts must be changed in response to layout variations.

[0011] An object of the present disclosure is to provide a post-treatment system that allows for the sharing of parts. [Means for solving the problem]

[0012] In order to achieve the above object, the aftertreatment system in the present disclosure comprises: An aftertreatment system including a tubular first treatment section that extends in a first cylinder axis direction and treats exhaust gas discharged from an internal combustion engine, and a tubular second treatment section that is disposed downstream of the first treatment section and extends in a second cylinder axis direction and treats the exhaust gas, a first pipe extending in a direction forming a first angle with respect to the first cylindrical axis direction and rotatable about the first cylindrical axis, for guiding the exhaust gas processed by the first processing unit; a second pipe extending in a direction forming a second angle with respect to the second cylindrical axis direction and arranged rotatably around the second cylindrical axis, and introducing the exhaust gas to be treated by the second treatment unit; a third pipe that is shaped to form an angle obtained by adding the first angle and the second angle and that connects the first pipe and the second pipe; Equipped with. [Effects of the Invention]

[0013] According to the present disclosure, it is possible to standardize parts. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a diagram showing an example of the layout of a post-processing system according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a view taken along the arrow A in FIG. [Figure 3] FIG. 3 is a perspective view showing a state in which the exhaust treatment device according to the embodiment of the present disclosure is assembled to a diesel particulate filter. [Figure 4] FIG. 4 is a front view showing a state in which the exhaust treatment device according to the embodiment of the present disclosure is assembled to a diesel particulate filter. [Figure 5] FIG. 5 is a plan view of the exhaust treatment device according to the embodiment of the present disclosure. [Figure 6] FIG. 6 is a front view of the exhaust treatment device according to the embodiment of the present disclosure, as viewed from the exhaust downstream side. [Figure 7] FIG. 7 is a rear view of the exhaust treatment device according to the embodiment of the present disclosure, as viewed from the exhaust upstream side. [Figure 8] FIG. 8 is a right side view of the exhaust treatment device according to the embodiment of the present disclosure. [Figure 9] FIG. 9 is a left side view of the exhaust treatment device according to the embodiment of the present disclosure. [Figure 10] FIG. 10 is a bottom view of the exhaust treatment device according to the embodiment of the present disclosure. [Figure 11] FIG. 11 is a diagram illustrating an example of the layout of the post-processing system according to the embodiment of the present disclosure. [Figure 12] FIG. 12 is a diagram showing another example of the layout of the post-processing system according to the embodiment of the present disclosure. [Figure 13] FIG. 13 is a view taken along the arrow B in FIG. [Figure 14] FIG. 14 is a diagram showing another example of the layout of the post-processing system according to the embodiment of the present disclosure. [Figure 15] FIG. 15 is a view taken along the arrow C in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. FIG. 1 is a diagram illustrating an example of the layout of an aftertreatment system according to an embodiment of the present disclosure. FIG. 2 is a view taken along the arrow A in FIG. 1. The aftertreatment system 100A shown in FIGS. 1 and 2 includes a diesel particulate filter (DPF) and a urea selective catalytic reduction device (SCR). The layouts of the DPF and SCR are set according to the vehicle model. The DPF collects and removes particulate matter (PM) in the exhaust gas emitted from the internal combustion engine. The aftertreatment system 100A may also include a diesel oxidation catalyst (DOC) that is disposed upstream of the DPF and that oxidizes fuel (HC) injected after the combustion process to raise the temperature of the exhaust gas and promote combustion within the DPF.

[0016] The DPF has a cylindrical wall extending in the direction of its cylinder axis, which is the direction extending along a straight line SL1.

[0017] The SCR is located downstream of the DPF and reduces the nitrogen oxides (NOx) contained in the exhaust by mixing the exhaust from which PM has been collected and removed with a reducing agent. Urea water ((NH2)2CO) is used as the reducing agent to be mixed with the exhaust. The urea water is decomposed into ammonia (NH3) by the heat of the exhaust. The ammonia produced by the decomposition of the urea water reduces the nitrogen oxides (NO x Through the above reaction process, nitrogen oxides are reduced to nitrogen (N2) and water (H2O).

[0018] The exhaust treatment device 100 (SCR) in this embodiment has a urea water evaporation chamber, a diffusion chamber, and an SCR catalyst. The layout of the urea water evaporation chamber, the diffusion chamber, and the SCR catalyst is set according to the vehicle model. Each of the urea water evaporation chamber, the diffusion chamber, and the SCR catalyst has a cylindrical wall and a cylindrical axis.

[0019] The urea water evaporation chamber is positioned so that its cylinder axis CS1 is aligned with a straight line SL1. The diffusion chamber and SCR catalyst are positioned so that their cylinder axes CS2 are aligned with a straight line SL2 that is perpendicular to the straight line SL1. A third pipe connects the first pipe located on the urea water evaporation chamber side with the second pipe located on the diffusion chamber side. The urea water evaporation chamber promotes the decomposition of the urea water. The diffusion chamber diffuses ammonia and nitrogen oxides in the exhaust. The SCR catalyst uses hydrocarbons (HC) as a reducing agent. This allows ammonia to selectively react with nitrogen oxides in the exhaust to produce nitrogen and moisture.

[0020] In this embodiment, three types of layouts, LYT1, LYT2, and LYT3, will be described. Layout LYT1 is a layout in which the cylinder axis CS2 (straight line SL2) of the SCR catalyst is perpendicular to the cylinder axis CS1 (straight line SL1) of the DPF. Layout LYT2 is a layout in which the DPF and SCR catalyst are arranged in parallel. Layout LYT3 is a layout in which the DPF and SCR catalyst are arranged in series.

[0021] (Layout LYT1) The layout LYT1 will be described below, followed by the layout LYT3.

[0022] In this embodiment, a urea water evaporation chamber will be described as an example of the exhaust treatment device 100. Fig. 3 is a perspective view showing the exhaust treatment device of this embodiment assembled to the DPF. Fig. 4 is a front view showing the exhaust treatment device of this embodiment assembled to the DPF. Fig. 5 is a plan view of the exhaust treatment device of this embodiment. Fig. 6 is a front view of the exhaust treatment device of this embodiment as seen from the exhaust downstream side. Fig. 7 is a rear view of the exhaust treatment device of this embodiment.

[0023] 3 to 7, the exhaust treatment device 100 includes a urea water evaporation chamber 10 (hereinafter simply referred to as "chamber"), a pipe 20, an injector 30 (see FIG. 5), a reducing agent evaporation plate 40, and a guide plate 50. The chamber 10 corresponds to the "first treatment unit" in the present disclosure. The pipe 20 corresponds to the "first pipe" in the present disclosure.

[0024] (Chamber 10) The chamber 10 has a cylindrical wall 12 formed, for example, from a stainless steel pipe. In Figures 4 and 7, a partition line PL extending in the vertical direction is indicated by a two-dot chain line. In the following description, the cylinder axis direction may be referred to as the "exhaust direction." One side of the cylinder axis direction may be referred to as the "exhaust upstream side," and the other side of the cylinder axis direction may be referred to as the "exhaust downstream side." A direction perpendicular to the cylinder axis direction may be referred to as the "radial direction." A direction radially away from the cylinder axis CS1 may be referred to as the "radial one side" or the "centrifugal direction," and a direction radially approaching the cylinder axis CS1 may be referred to as the "radial other side" or the "centripetal direction." In Figure 4, which shows the front of the exhaust treatment device 100, the right side may be referred to as the "right side," and the left side may be referred to as the "left side."

[0025] The chamber 10 has a one-side end wall 14 arranged at one end in the axial direction (upstream exhaust side), and an other-side end wall 15 arranged at the other end in the axial direction (downstream exhaust side).

[0026] As shown in Figures 3, 5, and 7, the one-side end wall 14 is divided into two regions: a left side wall 14L located to the left of the partition line PL, and a right side wall 14R located to the right of the partition line PL. In Figure 7, which is a rear view of the exhaust treatment device 100, the left side wall 14L is shown to the right of the partition line PL, and the right side wall 14R is shown to the left of the partition line PL. The one-side end wall 14 is a circular wall that extends radially from the cylindrical axis CS1. An inlet 16 is opened in the one-side end wall 14 for introducing exhaust gas from the DPF (not shown) side. The inlet 16 is an arc-shaped opening that has a predetermined width in the radial direction and extends counterclockwise from the 12 o'clock position to the 6 o'clock position of the circular one-side end wall 14.

[0027] As shown in FIGS. 3 to 6, the other-side end wall 15 is divided into two regions: a left side wall 15L located to the left of the partition line PL, and a right side wall 15R located to the right of the partition line. The other side end wall 15 closes the other end of the chamber 10 in the axial direction (the exhaust downstream side). The left side wall 15L has a wall surface that extends radially from the cylindrical axis CS1 in a substantially semicircular shape. In other words, the wall surface of the left side wall 15L extends counterclockwise from the 12 o'clock position to the 6 o'clock position. The right side wall 15R has a wall surface that extends radially from the cylindrical axis CS1 in a substantially semicircular shape. In other words, the wall surface of the right side wall 15R extends counterclockwise from the 6 o'clock position to the 12 o'clock position. Furthermore, the wall surface of the right side wall 15R is inclined at a predetermined angle θ toward one side in the axial direction (the exhaust upstream side) relative to the wall surface of the left side wall 15L (see FIG. 5).

[0028] The chamber 10 is divided into two spaces: a left chamber portion 10L located to the left of the dividing line PL, and a right chamber portion 10R located to the right of the dividing line PL. The overall length of the left chamber portion 10L in the axial direction is a constant length CL0 (see FIG. 5). In contrast, the overall length of the right chamber portion 10R in the axial direction gradually decreases counterclockwise from the 6 o'clock position to the 3 o'clock position because the wall surface of the right side wall 15R is inclined toward one axial direction side (the exhaust upstream side) with respect to the cylindrical axis CS1. Specifically, the overall length of the right chamber portion 10R in the axial direction decreases from length CL0 to length CL1 (see FIG. 5). As a result, the cross-sectional area of ​​the right chamber portion 10R (the cross-sectional area on a plane perpendicular to the axial direction of the right chamber portion 10R) narrows from the other axial direction side toward one axial direction side.

[0029] (Pipe 20) FIG. 8 is a right side view of an exhaust treatment device according to this embodiment. FIG. 9 is a left side view of an exhaust treatment device according to this embodiment. As shown in FIGS. 3 to 6, 8, and 9, the pipe 20 has a pipe axis PS and a pipe peripheral wall 22 and is formed, for example, from a stainless steel pipe. The pipe axis PS is indicated by a dashed line in FIG. 5. The pipe 20 has a bent portion PS1 bent at the center in the pipe axial direction. A portion PS2 on one side in the pipe axial direction from the bent portion PS1 extends along the cylindrical axis CS1. A portion PS3 on the other side in the pipe axial direction from the bent portion PS1 extends in a direction inclined at a predetermined angle α with respect to the cylindrical axis CS1 (see FIG. 5). The inclination angle α of the other side portion PS3 in the pipe axial direction with respect to the cylindrical axis CS1 is the same as the inclination angle θ of the wall surface of the right side wall 15R with respect to the wall surface of the left side wall 15L (α = θ).

[0030] One axial end of the pipe 20 is a closed end closed by one end wall 14. The other axial end of the pipe 20 is an open end. An inlet 24 is provided in the peripheral pipe wall 22 at one axial end portion PS2. An outlet 26 serving as an open end is provided at the other axial end portion PS3. The outlet 26 is located outside the chamber 10.

[0031] The pipe peripheral wall 22 is disposed so as to be surrounded from the outside by the cylindrical wall 12. As a result, a circumferential space 18 extending circumferentially is formed between the pipe peripheral wall 22 and the cylindrical wall 12. Similar to the chamber 10, which is divided into two spaces by the partition line PL, the circumferential space 18 is divided into two spaces: a left circumferential space 18L (see FIG. 6) located to the left of the partition line PL, and a right circumferential space 18R (see FIG. 6) located to the right of the partition line PL. Similar to the cross-sectional area of ​​the right chamber portion 10R, the cross-sectional area of ​​the right circumferential space 18R narrows from the other side in the cylindrical axis direction toward the one side in the cylindrical axis direction. One side (the exhaust upstream side) of the left circumferential space 18L is connected to the inlet 16. As a result, exhaust gas from the DPF is introduced into the left circumferential space 18L through the inlet 16, and the introduced exhaust gas can move from the left circumferential space 18L to the right circumferential space 18R. Furthermore, the exhaust gas that has moved to the right circumferential space 18R can move from the other side in the axial direction toward one side in the axial direction. In other words, the exhaust gas from the DPF can move from the left circumferential space 18L toward one side in the axial direction of the right circumferential space 18R. The exhaust gas flow direction is indicated by the thick arrow in Figure 3.

[0032] (Injector 30) The injector 30 is disposed in the cylindrical wall 12 of the left chamber portion 10L (see FIG. 4). The nozzle of the injector 30 faces from the cylindrical wall 12 side toward the left circumferential space 18L. This enables the injector 30 to inject a reducing agent (urea water) toward the exhaust gas introduced into the left circumferential space 18L from the inlet 16. In FIG. 4, the flow direction of the exhaust gas is indicated by a hatched arrow, and the flow direction of the reducing agent is indicated by a hollow arrow.

[0033] (reducing agent evaporation plate 40) FIG. 10 is a bottom view of the exhaust treatment device according to this embodiment. As shown in FIGS. 3 to 10, the reducing agent evaporation plate 40 is a flat plate member located within the circumferential space 18 and arranged along the cylindrical wall 12. Specifically, the reducing agent evaporation plate 40 is located between the cylindrical wall 12 and the pipe circumferential wall 22 and extends circumferentially in a counterclockwise direction from the 9 o'clock position to the 4 o'clock position. That is, the reducing agent evaporation plate 40 extends circumferentially from the left circumferential space 18L to the right circumferential space 18R. The reducing agent evaporation plate 40 has an inner wall surface WS1 facing the pipe circumferential wall 22 and an outer wall surface WS2 facing the cylindrical wall 12. The inner wall surface WS1 is positioned so that the reducing agent injected from the injector 30 hits it. Exhaust gas and reducing agent (urea water) flow through the gap between the pipe circumferential wall 22 and the inner wall surface WS1. Exhaust gas flows through the gap between the cylindrical wall 12 and the outer wall surface WS2. As a result, the reducing agent flowing in the gap between the pipe peripheral wall 22 and the inner wall surface WS1 is decomposed into ammonia by the heat of the exhaust gas flowing in the gap between the cylindrical wall 12 and the outer wall surface WS2. Note that the chamber 10 is called a "urea water evaporation chamber" because the reducing agent (urea water) is decomposed into ammonia by the heat of the exhaust gas.

[0034] The total length in the axial direction of the reducing agent evaporator plate 40 in the left circumferential space 18L is a constant length VL0 (see FIG. 10). The total length in the axial direction of the reducing agent evaporator plate 40 in the right circumferential space 18R, like the total length in the axial direction of the right chamber portion 10R, gradually decreases counterclockwise from the 6 o'clock position toward the 4 o'clock position because the wall surface of the right side wall 15R is inclined toward one axial side (exhaust upstream side) with respect to the cylindrical axis CS1. Specifically, the total length in the axial direction of the reducing agent evaporator plate 40 in the right circumferential space 18R decreases from length VL0 to length VL1 (see FIG. 10).

[0035] (Signboard 50) The guide plate 50 is bent at a central portion 51 in the axial direction, similar to the pipe 20 that is bent at a central portion (bending portion PS1) in the axial direction. The guide plate 50 extends radially from the 12 o'clock position of the pipe circumferential wall 22 to the tubular wall 12, with one radial side connected to the tubular wall 12 and the other radial side connected to the pipe circumferential wall 22. As a result, the guide plate 50 blocks the movement of exhaust gas and ammonia that have moved from the left circumferential space 18L (see FIG. 6) to the right circumferential space 18R (see FIG. 6) so as not to return from the right circumferential space 18R to the left circumferential space 18L. Note that the exhaust gas and ammonia move through the right circumferential space 18R from the other axial side toward the one axial side of the cylinder.

[0036] The guide plate 50 blocks the movement of the exhaust gas and ammonia from the right circumferential space 18R to the left circumferential space 18L, while guiding the exhaust gas and ammonia that have moved within the right circumferential space 18R toward one side in the axial direction of the cylinder from the right circumferential space 18R toward the inlet 24. The exhaust gas and ammonia that have been guided to the inlet 24 enter a position on one side of the pipe axis of the pipe 20, move from that position to a position on the other side of the pipe axis, and are discharged from the outlet 26 to the outside of the chamber 10.

[0037] (SCR catalyst 60, diffusion chamber 70, second pipe 80, connecting pipe 90) Next, the layout LYT1 of the aftertreatment system 100A in this embodiment will be described with reference to FIG. 11. The DPF, urea water evaporation chamber, first pipe, SCR catalyst, diffusion chamber, second pipe, and third pipe shown in FIG. 1 correspond to the DPF, chamber 10, pipe 20, SCR catalyst 60, diffusion chamber 70, second pipe 80, and connecting pipe 90 shown in FIG. 11, respectively. The chamber 10 and diffusion chamber 70 shown in FIG. 11 correspond to the "first chamber" and "second chamber" in this disclosure. FIG. 11 shows a line SL1' parallel to the line SL1 and a line SL2' parallel to the line SL2. As described above, the cylinder axis CS2 (line SL2) is a line perpendicular to the cylinder axis CS1 (line SL1). Therefore, the line SL2' is perpendicular to the line SL1'.

[0038] As shown in Figure 11, a diffusion chamber 70 for diffusing exhaust gas and ammonia is connected to the chamber 10. Specifically, a second pipe 80 is disposed in the diffusion chamber 70. The second pipe 80 is connected to the pipe 20 (first pipe) by a connecting pipe 90 (third pipe). This allows the ammonia to react with nitrogen oxides in the exhaust gas, and in the reaction process, the nitrogen oxides are reduced to nitrogen and moisture.

[0039] As described above, the other axial side portion PS3 of the pipe 20 extends in a direction inclined at a predetermined angle α with respect to the cylindrical axis CS1. The pipe 20 is arranged so as to be rotatable around the cylindrical axis CS1 with respect to the chamber 10. The pipe 20 is fixed to the chamber 10 at a predetermined rotation angle.

[0040] The second pipe 80 has a pipe axis PS4 and a pipe peripheral wall, and is formed, for example, from a stainless steel pipe. The pipe axis PS4 is indicated by a dashed line in FIG. 11. The pipe axis PS4 extends in a direction inclined at a predetermined angle β with respect to the line SL2. The inlet of the second pipe 80 is located outside the diffusion chamber 70. The outlet of the second pipe 80 communicates with the interior of the diffusion chamber 70. The second pipe 80 is arranged rotatable around a cylindrical axis SC2 relative to the diffusion chamber 70. The second pipe 80 is fixed to the diffusion chamber 70 at a predetermined rotation angle.

[0041] The connecting pipe 90 has an upstream end connected to the outlet 26 of the pipe 20 and a downstream end connected to the inlet of the second pipe 80. The central portion between the upstream and downstream ends of the connecting pipe 90 has a bent portion 91 that bends at a predetermined angle (α+δ). As described above, the line SL2' is perpendicular to the line SL1'. Therefore, the angle δ is π / 2-β. The angle γ shown in FIG. 11 is π / 2-α.

[0042] Next, the relationships between the angles α, β, γ, and δ are assumed to be expressed by the following formulas (1) and (2). α+δ=γ+δ=α+δ (1) α+β+γ+δ=π (2) From equations (1) and (2), the following equation is established: α=β=γ=δ=π / 4 (3)

[0043] That is, the connection pipe 90 has a bent portion 91 that is bent at a predetermined angle (α+δ=π / 2). In this embodiment, the connection pipe 90 only needs to be shaped to form the predetermined angle (α+β).

[0044] (Layout LYT2) Next, layout LYT2 will be described with reference to Fig. 12 and Fig. 13. Fig. 12 is a diagram showing another example of the layout of the post-processing system according to the embodiment of the present disclosure. Fig. 13 is a view taken along arrow B in Fig. 12. Note that the description of layout LYT2 will mainly focus on configurations that differ from layout LYT1, and the same configurations will be denoted by the same reference numerals and will not be described again.

[0045] As described above, the layout LYT2 is a layout in which the DPF and the SCR catalyst are arranged in parallel.

[0046] In layout LYT2, the above formula (3) holds true, just like in layout LYT1. As a result, even when the layout of aftertreatment system 100A is set to layout LYT2 depending on the vehicle model, it is possible to use the same components as those of exhaust treatment device 100 (SCR) in the above embodiment, namely, chamber 10, pipe 20, SCR catalyst 60, diffusion chamber 70, second pipe 80, and connecting pipe 90.

[0047] (Layout LYT3) Next, layout LYT3 will be described with reference to Fig. 14 and Fig. 15. Fig. 14 is a diagram showing another example of the layout of the post-processing system according to the embodiment of the present disclosure. Fig. 15 is a view taken along arrow C in Fig. 14. Note that the description of layout LYT3 will mainly focus on configurations that differ from layout LYT1, and the same configurations will be denoted by the same reference numerals and descriptions thereof will be omitted.

[0048] As described above, the layout LYT3 is a layout in which the DPF and the SCR catalyst are arranged in series.

[0049] In layout LYT3, the above formula (3) holds true, just like in layout LYT1. As a result, even when the layout of aftertreatment system 100A is set to layout LYT3 depending on the vehicle model, it is possible to use the same components as those of exhaust treatment device 100 (SCR) in the above embodiment, namely, chamber 10, pipe 20, SCR catalyst 60, diffusion chamber 70, second pipe 80, and connecting pipe 90.

[0050] The aftertreatment system 100A in the above embodiment is an aftertreatment system comprising: a cylindrical chamber 10 (urea water evaporation chamber) extending in the direction of a cylindrical axis CS1 and treating exhaust gas emitted from an internal combustion engine; and a cylindrical diffusion chamber 70 positioned downstream of the chamber 10 in the exhaust direction, extending in the direction of a cylindrical axis CS2 and treating exhaust gas; a pipe 20 (first pipe) extending in a direction that forms a first angle with respect to the direction of the cylindrical axis CS1 and rotatable about the cylindrical axis CS1, for discharging exhaust gas treated by the chamber 10; a second pipe 80 extending in a direction that forms a second acute angle with respect to the direction of the cylindrical axis CS2 and rotatable about the cylindrical axis CS2, for introducing exhaust gas to be treated by the diffusion chamber 70; and a connecting pipe 90 formed so as to form the first angle and a second angle, for connecting the pipe 20 and the second pipe 80.

[0051] With the above configuration, the chamber 10 (urea water evaporation chamber) and the diffusion chamber 70 can be arranged so that the cylindrical axes CS1 and CS2 are perpendicular to each other, so that they are arranged in parallel with each other, and so that they are arranged in series with each other, so that the layout of the aftertreatment system 100A can be set according to the vehicle model without changing the components that make up the aftertreatment system. This makes it possible to share parts in the aftertreatment system 100A.

[0052] In the aftertreatment system of the above embodiment, the pipe 20 (first pipe), the second pipe 80, and the connecting pipe 90 (third pipe) each have the same diameter. This makes it possible to suppress changes in the flow speed of the exhaust gas flowing through each of the pipes 20, the second pipe 80, and the connecting pipe 90. It also makes it possible to manufacture each pipe from the same material.

[0053] The aftertreatment system in the above embodiment has a chamber 10 located at the downstream end of the first treatment section, with a mixer device located in chamber 10 that mixes exhaust with a reducing agent, and a diffusion chamber 70 located at the upstream end of the second treatment section, with a diffuser device located in diffusion chamber 70 that diffuses the mixed exhaust and reducing agent. This makes it possible to share the components of chamber 10, diffusion chamber 70, mixer device, and diffuser device.

[0054] In the post-processing system according to the above embodiment, the first acute angle and the second acute angle are the same, π / 4, so that the bending angle of the bent portion 91 of the connection pipe 90, which is bent at an angle obtained by adding the first acute angle and the second acute angle, is π / 2.

[0055] In the post-processing system of the above embodiment, the first angle of the pipe 20 relative to the cylindrical axis CS1 is a first acute angle, but it may be a right angle or an obtuse angle. Furthermore, the second angle of the second pipe 80 relative to the cylindrical axis CS2 is a second acute angle, but it may be a right angle or an obtuse angle. For example, the first angle may be a right angle or an obtuse angle, and the second angle may be an acute angle. Conversely, the first angle may be an acute angle, and the second angle may be a right angle or an obtuse angle. Furthermore, for example, the first angle may be an obtuse angle, and the second angle may be an obtuse angle. Even in this case, the connecting pipe 90 is formed to form an angle obtained by adding the first angle and the second angle. For example, if the first angle is a right angle and the second angle is a right angle, the connecting pipe 90 is formed to form two right angles. In other words, the connecting pipe 90 is a straight pipe that is not bent.

[0056] Furthermore, the above-described embodiments are merely examples of specific embodiments for carrying out the present disclosure, and the technical scope of the present disclosure should not be interpreted as being limited by these embodiments. In other words, the present disclosure can be carried out in various forms without departing from its gist or main features. [Industrial Applicability]

[0057] The present disclosure is suitably used in vehicles equipped with aftertreatment systems that require the use of common parts. [Explanation of symbols]

[0058] CL0 length CL1 length CS1 cylinder shaft CS2 cylinder shaft PL dividing line PS pipe shaft PS1 bending part PS2 Pipe axial direction one side PS3 Other side of pipe in axial direction PS4 Pipe Shaft SL1 Straight Line SL1' Straight line SL2 straight line SL2' straight line VL0 Length VL1 Length WS1 Inner wall WS2 outer wall 10 chambers 10L left chamber 10R right chamber part 12 Cylindrical wall 14 One side end wall 15 Other end wall 15L left side wall 15R right side wall 16 Introduction 16A Introduction hole 18 Circumferential space 18L left circumferential space 18R Right circumferential space 20 Pipe 22 Pipe wall 24 Entrance 24A Entrance 26 Exit 30 injectors 40 Reducing agent evaporation plate 50 Signboard 51 Central part 60 SCR catalyst 70 Diffusion Chamber 80 Second Pipe 90 Connecting Pipe 91 Bend part 100 Exhaust treatment device 100A Aftertreatment System

Claims

1. An aftertreatment system including a cylindrical first treatment section that extends in a first cylinder axis direction and treats exhaust gas discharged from an internal combustion engine, and a cylindrical second treatment section that is disposed downstream of the first treatment section, extends in a second cylinder axis direction, and treats the exhaust gas, a first pipe extending in a direction forming a first angle with respect to the first cylinder axis direction and arranged rotatably about the first cylinder axis, and configured to guide the exhaust gas processed by the first processing unit; a second pipe extending in a direction forming a second angle with respect to the second cylinder axis direction and arranged rotatably about the second cylinder axis, and introducing the exhaust gas to be treated by the second treatment unit; a third pipe that is shaped to form an angle obtained by adding the first angle and the second angle and that connects the first pipe and the second pipe; Equipped with Aftertreatment system.

2. The first pipe, the second pipe, and the third pipe each have the same diameter. The aftertreatment system of claim 1 .

3. a first chamber disposed at an end of the first processing section on the downstream side of exhaust gas; a mixer device that mixes a reducing agent with the exhaust gas is disposed in the first chamber; a second chamber disposed at an upstream end of the second processing section; A diffusion device that diffuses the mixed exhaust gas and the reducing agent is disposed in the second chamber. The aftertreatment system of claim 1 .

4. the first angle is a first acute angle; the second angle is a second acute angle. The aftertreatment system of claim 1 .

5. the first acute angle and the second acute angle are the same angle as each other, π / 4; The aftertreatment system of claim 4 .

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