Exhaust parts

Abstract

To reduce pressure loss of exhaust gas.SOLUTION: An exhaust component includes a first member and a second member. The first member forms a first flow channel as a flow channel of exhaust gas, and the second member forms a second flow channel as a flow channel having a cross-section area of the flow channel smaller than that of the first flow channel. The first member has a hole forming part as a site for forming a through hole. A tip portion of the hole forming part is a site bent from the periphery of the through hole, projecting to the outside of the first member, and going around the through hole. An upstream end part as an end part at the upstream side of the second flow channel in the second member is joined to the hole forming part so as to cover an outer peripheral surface of the hole forming part. The second flow channel is a flow channel into which exhaust gas passes through the through hole and flows from the upstream end part.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to exhaust components. [Background technology]

[0002] There is known a technique for extracting exhaust gas generated in an internal combustion engine from a flow path that the exhaust gas flows in. For example, Patent Document 1 discloses a technique in which an EGR (Exhaust Gas Recirculation) pipe is inserted into a hole provided in a case that forms the exhaust gas flow path, and the exhaust gas extracted from the case is circulated through the EGR pipe to the internal combustion engine. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-092066 Summary of the Invention [Problem to be solved by the invention]

[0004] The exhaust system of an internal combustion engine may be equipped with a catalyst that functions as a filter to capture exhaust particulates contained in exhaust gas. The filter of this catalyst becomes clogged with use. Therefore, it is common to detect filter clogging. For example, filter clogging can be detected by extracting exhaust gas from the exhaust gas flow path and measuring the exhaust gas pressure. In this case, in conventional technology, the end of a pipe is inserted into a hole, and the inner diameter of the pipe narrows sharply compared to the diameter of the exhaust gas flow path inside the case. This poses a problem of large exhaust gas pressure loss (in other words, inlet loss) when extracting exhaust gas from the case to the pipe.

[0005] One aspect of the present disclosure is to reduce exhaust gas pressure loss. [Means for solving the problem]

[0006] One aspect of the present disclosure is an exhaust component comprising a first member and a second member. The first member forms a first flow path for exhaust gas. The second member forms a second flow path having a smaller cross-sectional area than the first flow path. The first member has a hole forming portion where a through hole is formed.

[0007] The tip portion of the hole forming portion is a portion that curves from the periphery of the through hole, protrudes to the outside of the first member, and goes around the through hole. The upstream end portion of the second member, which is the upstream end portion of the second flow path, is joined to the hole formation portion so as to cover the outer peripheral surface of the hole formation portion. The second flow path is a flow path into which exhaust gas passes through the through hole and flows in from the upstream end portion.

[0008] With this configuration, the pressure loss of the exhaust gas can be reduced. In one aspect of the present disclosure, the end face of the upstream end may be formed so as to form an obtuse angle with the outer circumferential surface of the hole forming portion.

[0009] According to this configuration, it is possible to improve the stability of the joining when joining the upstream end of the second member to the hole forming portion of the first member. In one aspect of the present disclosure, the inner circumferential surface of the upstream end may be formed so as to widen radially outward from the downstream side to the upstream side of the second flow path.

[0010] According to this configuration, it is possible to improve the accuracy when joining the upstream end of the second member to the hole forming portion of the first member. In one embodiment of the present disclosure, the hole forming portion may be curved toward the outside of the first member at an angle greater than 0 degrees and equal to or less than 90 degrees.

[0011] According to this configuration, it becomes easy to process the second member to be joined to the hole forming portion of the first member. In one embodiment of the present disclosure, the first member may be configured as a case with a catalyst therein, and the second member may be configured as a pipe connected to a sensor or an EGR pipe.

[0012] According to this configuration, it is possible to reduce the pressure loss of exhaust gas in a device in which an EGR pipe or a pipe for a sensor is attached to a catalyst case. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 2 is a schematic diagram of an exhaust component. [Figure 2] 2 is a cross-sectional view of a joint portion between a case 2 and a pipe 3 in the exhaust part of the first embodiment. FIG. [Figure 3] 3 is a cross-sectional view of the exhaust part of the first embodiment, showing how a case 2 and a pipe 3 are joined together. FIG. [Figure 4] 10 is a cross-sectional view showing how the case 2 and the pipe 3 are joined together in an exhaust part according to another embodiment. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings. [1. First embodiment] [1-1.Configuration] [1-1-1. Overall structure] 1 is a component that is mounted on a vehicle such as an automobile and that constitutes at least a part of a flow path for exhaust gas generated by an internal combustion engine of the vehicle. In this embodiment, the exhaust component 1 is a catalytic converter.

[0015] The exhaust part 1 includes a case 2 , a pipe 3 , and a pressure sensor 4 . The case 2 is a member that forms inside it a first flow path A, which is a flow path for exhaust gas, and includes a catalyst 7 and a retention mat 8. In Fig. 1, the catalyst 7 and retention mat 8 that are arranged inside the case 2 are indicated by dashed lines.

[0016] The catalyst 7 is disposed on the first flow path A inside the case 2. The catalyst 7 has a filter function that collects exhaust particulates. The exhaust gas flowing through the first flow path A is purified by passing through the inside of the catalyst 7.

[0017] The support mat 8 is a member that is disposed so as to close the gap between the inner surface of the case 2 and the catalyst 7, and supports the catalyst 7. The pipe 3 is a cylindrical member that defines a second flow path B therein, the second flow path B having a smaller cross-sectional area than the first flow path A. The outer diameter of the pipe 3 is, for example, several millimeters to several centimeters. The pipe 3 has an upstream end portion 31, which is the end portion of the pipe 3 upstream of the second flow path B, and a main body portion 32, which is adjacent to the upstream end portion 31 and extends along the second flow path B. The main body portion 32 is the substantial portion of the pipe 3 that defines the second flow path B.

[0018] The upstream end 31 is disposed so that the second flow path B communicates with the first flow path A via a through hole 22 provided in the side surface 21 of the case 2. That is, at least a portion of the exhaust gas flowing through the first flow path A of the case 2 branches off from the first flow path A, passes through the through hole 22, and flows into the second flow path B from the upstream end 31 of the pipe 3. The pipe 3 is connected to a pressure sensor 4.

[0019] The pressure sensor 4 is a sensor that measures the pressure of the exhaust gas flowing through the second flow path B in the pipe 3. In the case 2, the through-holes 22 are provided on both the upstream side and downstream side of the first flow path A with respect to the catalyst 7. The pipe 3 and the pressure sensor 4 are provided in the through-holes 22 on the upstream side and downstream side, respectively.

[0020] The upstream and downstream pressure sensors 4 can measure the pressure difference between the exhaust gases flowing into the second flow path B from the upstream and downstream sides of the first flow path A relative to the catalyst 7. Normally, in the first flow path A, the pressure of the exhaust gases upstream of the catalyst 7 is greater than the pressure of the exhaust gases downstream of the catalyst 7. The greater the exhaust gas pressure difference, the more clogged the filter of the catalyst 7 is likely to be.

[0021] The exhaust system of the vehicle is configured, for example, to combust unburned fuel supplied to the vehicle on the filter of the catalyst 7 when the pressure difference of the exhaust gas exceeds a predetermined value, thereby removing exhaust particulates and eliminating clogging of the filter of the catalyst 7.

[0022] [1-1-2. Configuration of hole forming section and upstream end] As shown in FIG. 2, the case 2 has a hole forming portion 23 on the side surface 21, which is a portion where the through hole 22 is formed.

[0023] The tip of the hole forming portion 23 curves from the periphery of the through hole 22, protrudes to the outside of the case 2, and circles the through hole 22. When an imaginary plane 21a, which is located on approximately the same plane as the portion of the side surface 21 adjacent to the hole forming portion 23, is used as a reference, the hole forming portion 23 curves from the imaginary plane 21a toward the outside of the case 2 by an angle θ1. In other words, the angle θ1 is the angle between the direction in which the portion of the side surface 21 of the case 2 adjacent to the hole forming portion 23 widens and the direction in which the hole forming portion 23 protrudes. In this embodiment, the angle θ1 is greater than 0 degrees and less than 90 degrees. One example of a method for forming the hole forming portion 23 is burring. The hole forming portion 23 is formed so that the diameter of the through hole 22 on the imaginary plane 21a is larger than the diameter of the main body portion 32 of the pipe 3. Instead of burring, the hole forming portion 23 may be formed by fixing a separate ring-shaped member surrounding the through-hole 22 of the case 2 to the case 2 by welding.

[0024] The upstream end 31 of the pipe 3 is joined to the hole forming portion 23 so as to cover the outer peripheral surface 24 of the hole forming portion 23. Examples of joining include welding and adhesive bonding. By joining, the gap between the inner peripheral surface of the upstream end 31 and the outer peripheral surface 24 of the hole forming portion 23 is closed.

[0025] The upstream end 31 curves radially outward at the portion where it connects to the main body 32. The inner circumferential surface of the upstream end 31 is formed to widen radially outward from the downstream side of the second flow path B toward the upstream side. In other words, the inner circumferential surface of the upstream end 31 is formed so that the cross-sectional area of ​​the second flow path B formed by the upstream end 31 is continuously or discontinuously larger than the cross-sectional area of ​​the second flow path B formed by the main body 32. One example of a method for forming the upstream end 31 is flaring. The inner circumferential surface of the upstream end 31 may be tapered or stepped. At least a portion of the inner circumferential surface of the upstream end 31 abuts against the outer circumferential surface 24 of the hole forming portion 23.

[0026] 3, the end face 33 of the upstream end portion 31 is formed so that the angle θ2 formed with the outer peripheral surface 24 of the hole forming portion 23 is an obtuse angle. One example of a method for forming the end face 33 is bevel processing.

[0027] [1-2. Actions and Effects] According to the embodiment described above in detail, the following actions and effects can be obtained. (1a) The tip portion of the hole forming portion 23 of the case 2 is a portion that curves from the periphery of the through hole 22, protrudes to the outside of the case 2, and goes around the through hole 22. The upstream end 31 of the pipe 3 is joined to the hole forming portion 23 so as to cover the outer peripheral surface 24 of the hole forming portion 23. At least a portion of the exhaust gas flowing through the first flow path A of the case 2 branches off from the first flow path A, passes through the through hole 22, and flows into the second flow path B from the upstream end 31 of the pipe 3.

[0028] With this configuration, the diameter of the exhaust gas flow path gradually narrows as the exhaust gas flows from the first flow path A to the second flow path B. Therefore, the pressure loss of the exhaust gas is smaller than when the curved portion of the hole formation portion 23 has a bent shape with corners instead of a curve. Furthermore, the pressure loss of the exhaust gas is smaller than when the upstream end 31 is inserted into the through hole 22 and is not curved. Therefore, the pressure loss of the exhaust gas can be reduced. In other words, a portion of the exhaust gas flowing through the first flow path A can be guided to the second flow path B in a state where turbulence is less likely to occur.

[0029] Furthermore, in the process of joining the upstream end 31 and the hole forming portion 23 during manufacturing, the hole forming portion 23 protruding outward from the case 2 makes it easier to position the upstream end 31 when joining the upstream end 31 to the hole forming portion 23. This makes it possible to improve the accuracy of joining the upstream end 31 and the hole forming portion 23.

[0030] (1b) The end face 33 of the upstream end portion 31 is formed so that the angle θ2 formed with the outer peripheral surface 24 of the hole forming portion 23 is an obtuse angle. With this configuration, in the process of joining the upstream end portion 31 and the hole forming portion 23 during manufacturing, for example, when fillet welding the end face 33 and the outer peripheral surface 24, welding becomes easier. Specifically, as shown in Fig. 3, the tip of the welding wire 9 can be more easily applied to the portions to be welded on the end face 33 and the outer peripheral surface 24 than when the end face 33 and the outer peripheral surface 24 are perpendicular to each other (in other words, when the angle θ2 is a right angle). This improves the stability of the joining.

[0031] (1c) The upstream end 31 curves radially outward at the portion where it connects to the main body 32. The inner circumferential surface of the upstream end 31 is formed to widen radially outward from the downstream side of the second flow path B toward the upstream side.

[0032] This configuration makes it easy to position the upstream end 31 when joining the upstream end 31 to the hole forming portion 23. This improves the accuracy of joining the upstream end 31 and the hole forming portion 23.

[0033] Furthermore, when the upstream end portion 31 and the hole forming portion 23 are welded together during manufacturing, a weld bead is generated on the inner surface of the upstream end portion 31 or the hole forming portion 23 (in other words, the back surface of the portion to be welded), which prevents the exhaust gas flow path from becoming narrow or blocked.

[0034] (1d) The hole forming portion 23 is formed so that the diameter of the through hole 22 on the imaginary plane 21a is larger than the diameter of the main body 32 of the pipe 3. The angle θ1 formed between the direction in which the portion of the side surface 21 of the case 2 adjacent to the hole forming portion 23 widens and the direction in which the hole forming portion 23 protrudes is larger than 0 degrees and smaller than 90 degrees.

[0035] This configuration makes it easy to position the upstream end 31 when joining the upstream end 31 to the hole forming portion 23. This makes it easy to process the upstream end 31. Furthermore, processing the upstream end 31 of the pipe 3 so as to cover the outer peripheral surface 24 of the hole forming portion 23 that forms the through hole 22 becomes easier than when the angle θ1 is 90 degrees or more.

[0036] (1e) The upstream end 31 of the pipe 3 is joined to the hole forming portion 23 so as to cover the outer peripheral surface 24 of the hole forming portion 23 . According to this configuration, the pipe 3 is not located inside the case 2. Therefore, the pipe 3 can be prevented from interfering with the flow of exhaust gas in the first flow path A inside the case 2.

[0037] [1-3. Correspondence between terms] In the above embodiment, the case 2 corresponds to an example of a first member, and the pipe 3 corresponds to an example of a second member.

[0038] 2. Other Embodiments Although the embodiments of the present disclosure have been described above, it goes without saying that the present disclosure is not limited to the above-described embodiments and can take on various forms.

[0039] (2a) In the above embodiment, the pipe 3 is connected to the pressure sensor 4. However, the pipe 3 is not limited to being connected to the pressure sensor 4, and may be connected to various other sensors. For example, the pipe 3 may be connected to a temperature sensor, a NOx (nitrogen oxide) sensor, or the like. The pipe 3 does not have to be connected to a sensor.

[0040] (2b) In the above embodiment, the angle θ1 is greater than 0 degrees and less than 90 degrees. However, the angle θ1 may be greater than or equal to 90 degrees. For example, as shown in FIG. 4, when the angle θ1 is 90 degrees, the upstream end 31 of the pipe 3 may have an expanded diameter section 31a whose diameter expands from the downstream side to the upstream side of the second flow path B, and a tip section 31b located upstream of the expanded diameter section 31a in the second flow path B. The tip section 31b may extend approximately perpendicular to the imaginary plane 21a. In other words, the tip section 31b may be approximately parallel to the direction in which the hole forming section 23 protrudes. The tip section 31b is joined to the hole forming section 23 so as to cover the outer peripheral surface 24 of the hole forming section 23. By joining, the gap between the inner peripheral surface of the tip section 31b and the outer peripheral surface 24 of the hole forming section 23 is closed.

[0041] According to this configuration, it is easy to position the upstream end 31 when joining the upstream end 31 to the hole forming portion 23. Therefore, it is easy to process the upstream end 31. (2c) In the above embodiment, the exhaust part 1 is a catalytic converter. However, the exhaust part 1 is not limited to a catalytic converter, and may be any part or device that includes a part for extracting exhaust gas from an exhaust gas flow path. For example, the exhaust part 1 may be an EGR device. The pipe 3 may be an EGR pipe for circulating exhaust gas purified by the catalyst 7 to the internal combustion engine.

[0042] (2d) Multiple functions of one component in the above embodiments may be realized by multiple components, or one function of one component may be realized by multiple components. Also, multiple functions of multiple components may be realized by one component, or one function realized by multiple components may be realized by one component. Also, part of the configuration of the above embodiments may be omitted. Also, at least part of the configuration of the above embodiments may be added to or substituted for the configuration of another of the above embodiments.

[0043] [Technical idea disclosed in this specification] [Item 1] An exhaust component, a first member that forms a first flow path that is a flow path for exhaust gas; a second member that forms a second flow path that is a flow path having a smaller cross-sectional area than the first flow path; Equipped with the first member has a hole forming portion that is a portion where a through hole is formed, a tip end portion of the hole forming portion is a portion that curves from the periphery of the through hole, protrudes to the outside of the first member, and goes around the through hole, an upstream end portion of the second member that is an end portion on the upstream side of the second flow path is joined to the hole forming portion so as to cover an outer peripheral surface of the hole forming portion; The second flow path is a flow path into which the exhaust gas passes through the through hole and flows in from the upstream end. Exhaust parts.

[0044] [Item 2] Item 1, an exhaust part according to item 1, an end face of the upstream end portion is formed so as to form an obtuse angle with an outer peripheral surface of the hole forming portion; Exhaust parts.

[0045] [Item 3] The exhaust part according to item 1 or 2, The inner circumferential surface of the upstream end portion is formed so as to widen radially outward from the downstream side toward the upstream side of the second flow path. Exhaust parts.

[0046] [Item 4] The exhaust part according to any one of items 1 to 3, The hole forming portion is curved toward the outside of the first member at an angle greater than 0 degrees and less than or equal to 90 degrees. Exhaust parts.

[0047] [Item 5] The exhaust part according to any one of items 1 to 4, The first member is configured as a case having a catalyst therein, The second member is configured as a pipe connected to a sensor or an EGR pipe. Exhaust parts. [Explanation of symbols]

[0048] 1...exhaust part, 2...case, 3...pipe, 22...through hole, 23...hole forming portion, 24...outer peripheral surface, 31...upstream end portion, A...first flow path, B...second flow path.

Claims

1. An exhaust component, a first member that forms a first flow path that is a flow path for exhaust gas; a second member that forms a second flow path that is a flow path having a cross-sectional area smaller than that of the first flow path; Equipped with the second member is configured as a pipe connected to a sensor; the first member has a hole forming portion that is a portion where a through hole is formed, a tip portion of the hole forming portion is a portion that curves from the periphery of the through hole, protrudes to the outside of the first member, and goes around the through hole, and has a tapered shape formed from the curved portion of the hole forming portion to the tip such that the diameter of the through hole becomes smaller toward the tip, an upstream end portion of the second member, which is an end portion on the upstream side of the second flow path, is joined to the hole forming portion by welding or adhesive so as to cover an outer peripheral surface of the hole forming portion; an inner circumferential surface of the hole forming portion corresponding to a portion where the first flow path and the through hole are connected is curved, The second flow path is a flow path that branches off from the first flow path, and the exhaust gas passes through the through hole and flows into the upstream end portion. Exhaust parts.

2. 2. The exhaust component of claim 1, an end face of the upstream end portion is formed so as to form an obtuse angle with an outer peripheral surface of the hole forming portion; Exhaust parts.

3. 3. The exhaust component according to claim 1 or 2, an inner circumferential surface of the upstream end portion is formed so as to widen radially outward from the downstream side toward the upstream side of the second flow path; Exhaust parts.

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