Exhaust component

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 Art

[0002] Techniques for extracting exhaust gas from a flow path through which exhaust gas generated by an internal combustion engine flows are known. 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 forming an exhaust gas flow path, and the exhaust gas extracted from the case through the EGR pipe is circulated to the internal combustion engine.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the exhaust system of an internal combustion engine, a catalyst having a filter function for collecting exhaust particles contained in exhaust gas may be mounted. As this catalyst is used, the filter becomes clogged. Therefore, detection of clogging of the filter has been carried out. Clogging of the filter can be detected, for example, by extracting exhaust gas from the exhaust gas flow path and measuring the pressure of the exhaust gas. At this time, in the prior art, since the end of the pipe is inserted into the hole and the inner diameter of the pipe suddenly becomes smaller than the exhaust gas flow path diameter in the case, there has been a problem that the pressure loss of the exhaust gas (in other words, the inlet loss) when extracting the exhaust gas from the case to the pipe becomes large.

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

Means for Solving the Problems

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

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

[0008] According to such a 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 portion may be formed such that the angle formed with the outer peripheral surface of the hole forming portion is an obtuse angle.

[0009] According to such a configuration, the joining stability when joining the upstream end portion of the second member to the hole forming portion of the first member can be improved. In one aspect of the present disclosure, the inner peripheral surface of the upstream end portion may be formed so as to widen radially outward as going from the downstream side to the upstream side of the second flow path.

[0010] According to such a configuration, the accuracy when joining the upstream end portion of the second member to the hole forming portion of the first member can be improved. In one aspect of the present disclosure, the hole forming portion may curve at an angle greater than 0 degrees and equal to or less than 90 degrees toward the outside of the first member.

[0011] According to such a configuration, the processing of the second member joined to the hole forming portion of the first member becomes easy. In one aspect of the present disclosure, the first member may be configured as a case having a catalyst inside. The second member may be configured as a pipe connected to a sensor or an EGR pipe.

[0012] According to such a configuration, in an apparatus for attaching an EGR pipe or a pipe for a sensor to a catalyst case, the pressure loss of the exhaust gas can be reduced.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out 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 Configuration] The exhaust component 1 shown in FIG. 1 is a component mounted on a vehicle such as an automobile and constitutes at least a part of the flow path of the exhaust gas generated by the internal combustion engine of the vehicle. In the present embodiment, the exhaust component 1 is a catalytic converter.

[0015] The exhaust component 1 includes a case 2, a pipe 3, and a pressure sensor 4. The case 2 is a member that forms an internal first flow path A, which is a flow path for exhaust gas, and includes a catalyst 7 and a holding mat 8. In FIG. 1, the catalyst 7 and the holding mat 8 disposed inside the case 2 are shown 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 for collecting 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 holding mat 8 is a member that is arranged to block 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 forms an internal second flow path B, which has a smaller cross-sectional area than the first flow path A. The outer diameter of the pipe 3 is, for example, from several millimeters to several centimeters. The pipe 3 has an upstream end 31 that is the upstream end of the second flow path B in the pipe 3, and a main body portion 32 that is adjacent to the upstream end 31 and extends along the second flow path B. The main body portion 32 is the substantial part that forms the second flow path B in the pipe 3.

[0018] The upstream end 31 is arranged such that the second flow path B communicates with the first flow path A through a through hole 22 provided in the side surface 21 of the case 2. That is, at least a part of the exhaust gas flowing through the first flow path A in the case 2 branches 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 the 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. The through hole 22 is provided in the case 2 on both the upstream side and the downstream side of the catalyst 7 with respect to the first flow path A. The pipe 3 and the pressure sensor 4 are provided in each of the upstream and downstream through holes 22.

[0020] The upstream and downstream pressure sensors 4 can measure the pressure difference of the exhaust gas flowing into the second flow path B from the upstream side and the downstream side of the catalyst 7 with respect to the first flow path A. Usually, in the first flow path A, the pressure of the exhaust gas on the upstream side of the catalyst 7 is greater than the pressure of the exhaust gas on the downstream side of the catalyst 7. The greater the pressure difference of the exhaust gas, the more likely it can be inferred that the filter of the catalyst 7 is clogged.

[0021] The exhaust system of the vehicle is configured to remove exhaust particulates and eliminate clogging of the filter of the catalyst 7, for example, by burning 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.

[0022] [Configuration of Hole Forming Portion and Upstream End Portion] As shown in FIG. 2, the case 2 has a hole forming portion 23 which is a portion forming a through hole 22 on the side surface 21.

[0023] The tip portion of the hole forming portion 23 curves from around the through hole 22 and protrudes outside the case 2, and is a portion that goes around the through hole 22. When the hole forming portion 23 is based on a virtual surface 21a that is located on substantially the same plane as the portion adjacent to the hole forming portion 23 on the side surface 21 in the through hole 22, the hole forming portion 23 is angled θ 1 only curved. In other words, the angle θ 1 is the angle formed by the direction in which the portion adjacent to the hole forming portion 23 on the side surface 21 of the case 2 spreads and the direction in which the hole forming portion 23 protrudes. In the present embodiment, the angle θ 1 is greater than 0 degrees and less than 90 degrees. As an example of a method for forming the hole forming portion 23, there is a flanging process. The hole forming portion 23 is formed such that the diameter of the through hole 22 is larger than the diameter of the main body portion 32 of the pipe 3 on the virtual surface 21a. Instead of the flanging process, the hole forming portion 23 may be formed by fixing a ring-shaped separate member surrounding the through hole 22 of the case 2 to the case 2 by welding.

[0024] The upstream end portion 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 adhesion. By the joining, the gap between the inner peripheral surface of the upstream end portion 31 and the outer peripheral surface 24 of the hole forming portion 23 is closed.

[0025] The upstream end portion 31 curves radially outward of the pipe 3 at the portion where it connects to the main body portion 32. The inner peripheral surface of the upstream end portion 31 is formed so as to widen radially outward as it goes from the downstream side to the upstream side of the second flow path B. In other words, the inner peripheral surface of the upstream end portion 31 is formed such that the cross-sectional area of the second flow path B formed by the upstream end portion 31 is continuously or discontinuously larger than the cross-sectional area of the second flow path B formed by the main body portion 32. As an example of a method of forming the upstream end portion 31, there is flaring. The inner peripheral surface of the upstream end portion 31 may be tapered, stepped, or the like. At least a part of the inner peripheral surface of the upstream end portion 31 abuts against the outer peripheral surface 24 of the hole forming portion 23.

[0026] As shown in FIG. 3, the end surface 33 of the upstream end portion 31 forms an angle θ 2 with the outer peripheral surface 24 of the hole forming portion 23 so as to be an obtuse angle. As an example of a method of forming the end surface 33, there is chamfering.

[0027] [1-2. Action, Effect] According to the embodiment described in detail above, the following actions and effects can be obtained. (1a) The tip portion of the hole forming portion 23 of the case 2 curves from around the through hole 22 and protrudes outside the case 2, and is a portion that goes around the through hole 22. The upstream end portion 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 part 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 portion 31 of the pipe 3.

[0028] According to such a configuration, the flow path of the exhaust gas when the exhaust gas flows from the first flow path A to the second flow path B gradually becomes narrower. For this reason, the pressure loss of the exhaust gas is smaller than in the case where the curved portion of the hole forming portion 23 has a bent shape with corners instead of curving. Also, the pressure loss of the exhaust gas is smaller than in the case where the upstream end portion 31 is inserted into the through hole 22 and the upstream end portion 31 is not curved. For this reason, the pressure loss of the exhaust gas can be reduced. That is, a part of the exhaust gas flowing through the first flow path A can be guided to the second flow path B in a state where turbulent flow is less likely to occur.

[0029] Further, in the step of joining the upstream end portion 31 and the hole forming portion 23 during manufacturing, the hole forming portion 23 protruding outside the case 2 facilitates positioning of the upstream end portion 31 when joining the upstream end portion 31 to the hole forming portion 23. Therefore, the joining accuracy between the upstream end portion 31 and the hole forming portion 23 can be improved.

[0030] (1b) The end face 33 of the upstream end portion 31 forms an obtuse angle θ with the outer peripheral surface 24 of the hole forming portion 23. 2 It is formed so as to be an obtuse angle. According to such a configuration, in the step 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, when the end face 33 and the outer peripheral surface 24 are orthogonal (in other words, when the angle θ 2 is a right angle), it is easier to apply the tip of the welding wire 9 to the welding portion on the end face 33 and the outer peripheral surface 24 than when they are not orthogonal. Therefore, the joining stability can be improved.

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

[0032] According to such a configuration, positioning of the upstream end portion 31 when joining the upstream end portion 31 to the hole forming portion 23 becomes easier. Therefore, the joining accuracy between the upstream end portion 31 and the hole forming portion 23 can be improved.

[0033] Furthermore, when welding the upstream end portion 31 and the hole forming portion 23 during manufacturing, it is possible to suppress the generation of welding beads on the inner peripheral surface of the upstream end portion 31 or the hole forming portion 23 (in other words, the back surface of the welding portion), and prevent the exhaust gas flow path from becoming narrow or blocked.

[0034] (1d) The hole forming portion 23 is formed such that the diameter of the through hole 22 is larger than the diameter of the main body portion 32 of the pipe 3 on the virtual surface 21a. The angle θ is the angle formed by the direction in which the portion adjacent to the hole forming portion 23 on the side surface 21 of the case 2 spreads and the direction in which the hole forming portion 23 protrudes. 1 is greater than 0 degrees and less than 90 degrees.

[0035] According to such a configuration, it becomes easy to position the upstream end portion 31 when joining the upstream end portion 31 to the hole forming portion 23. Therefore, it becomes easy to process the upstream end portion 31. Further, machining the upstream end portion 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 is easier when 1 the angle θ is 90 degrees or more.

[0036] (1e) The upstream end portion 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 such a configuration, the pipe 3 is not located inside the case 2. Therefore, it is possible to suppress the pipe 3 from obstructing the flow of exhaust gas in the first flow path A in the case 2.

[0037] [1-3. Corresponding relationships between terms] In the above embodiment, the case 2 corresponds to an example of the first member, and the pipe 3 corresponds to an example of the 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 embodiments and can take various forms.

[0039] (2a) In the above embodiment, the pipe 3 is connected to the pressure sensor 4. However, the pipe 3 may be connected not only to the pressure sensor 4 but also to various other sensors. For example, the pipe 3 may be connected to a temperature sensor, a NOx (nitrogen oxides) sensor, or the like. The pipe 3 may not be connected to a sensor.

[0040] (2b) In the above embodiment, the angle θ 1 is greater than 0 degrees and less than 90 degrees. However, the angle θ 1 may be 90 degrees or more. For example, as shown in FIG. 4, when the angle θ 1 is 90 degrees, the upstream end portion 31 of the pipe 3 may have a diameter-expanded portion 31a that expands in diameter from the downstream side to the upstream side of the second flow path B, and a tip portion 31b that is located on the upstream side of the second flow path B with respect to the diameter-expanded portion 31a. The tip portion 31b may extend substantially perpendicular to the virtual surface 21a. In other words, the tip portion 31b may be substantially parallel to the direction in which the hole forming portion 23 protrudes. The tip portion 31b is joined to the hole forming portion 23 so as to cover the outer peripheral surface 24 of the hole forming portion 23. By the joining, the gap between the inner peripheral surface of the tip portion 31b and the outer peripheral surface 24 of the hole forming portion 23 is closed.

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

[0042] (2d) A plurality of functions of one component in the above embodiment may be realized by a plurality of components, or one function of one component may be realized by a plurality of components. Also, a plurality of functions of a plurality of components may be realized by one component, or one function realized by a plurality of components may be realized by one component. Further, a part of the configuration of the above embodiment may be omitted. Also, at least a part of the configuration of the above embodiment may be added to or replaced with the configuration of another above embodiment.

[0043] [Technical idea disclosed in this specification] [Item 1] An exhaust component, a first member forming a first flow path that is a flow path for exhaust gas, a second member forming a second flow path that is a flow path having a smaller cross-sectional area than the first flow path, comprising: the first member has a hole forming portion which is a portion forming a through hole, a tip portion of the hole forming portion curves from around the through hole and protrudes to the outside of the first member, and is a portion surrounding the through hole, an upstream end portion which is an upstream end of the second flow path in the second member 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 through which the exhaust gas passes through the through hole and flows in from the upstream end portion, Exhaust component.

[0044] [Item 2] The exhaust component according to Item 1, an end surface of the upstream end portion is formed such that an angle formed with an outer peripheral surface of the hole forming portion is an obtuse angle, Exhaust component.

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

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

[0047] [Item 5] The exhaust component 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 the sensor or an EGR pipe, Exhaust component.

Description of reference signs

[0048] 1... Exhaust component, 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 part, comprising: A first member that forms a first flow path that is a flow path of 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 which is a portion where a through hole is formed, a tip portion of the hole forming portion is a portion that curves from a 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 portion. Exhaust parts.

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

3. 3. An exhaust component according to claim 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 passage. Exhaust parts.

4. 3. An exhaust component according to claim 1 or 2, 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.

5. 3. An exhaust component according to claim 1 or 2, 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.

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