Muffler

Abstract

To prevent a lid member for closing an end of a pipe from falling off from the pipe.SOLUTION: A muffler mounted on a vehicle includes an outer shell member, a pipe, and a closed part. The pipe is inserted into an opening of the outer shell member forming the internal space, and forms an exhaust flow path through which exhaust gas flows. The closing portion is provided at an end portion of the pipe that opens to the internal space, and is configured to close the exhaust flow path. The closed portion includes a slit and a lid member. The slit is provided in a wall of the pipe and extends from a first end to a second end in a direction intersecting a flow direction of the exhaust gas along the wall. The lid member includes a main body portion that closes the exhaust flow path, and an insertion portion that extends from the main body portion and is inserted into the slit.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present disclosure relates to a muffler. [Background technology]

[0002] There is a known technique for blocking one end of a pipe through which exhaust gas flows, which is inserted into a muffler, in order to change the direction in which the exhaust gas flows or to adjust the flow rate of the exhaust gas. Patent Document 1 discloses a muffler in which one end of a pipe closed by a cap is inserted inside the muffler. The cap is fixed to the pipe by being press-fitted into the pipe from the one end along the axial direction of the pipe. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-113706 Summary of the Invention [Problem to be solved by the invention]

[0004] However, since the above-mentioned cap is fixed inside the pipe by being pressed in along the axial direction, if the pressure of the exhaust gas flowing inside the pipe is high, it may be pushed by the pressure and fall off the pipe.

[0005] One aspect of the present disclosure aims to prevent a cover member that closes an end of a pipe from falling off the pipe. [Means for solving the problem]

[0006] One aspect of the present disclosure is a muffler to be mounted on a vehicle, comprising an outer shell member, a pipe, and a closing portion. The outer shell member forms an interior space. The pipe is inserted into an opening in the outer shell member to form an exhaust flow path through which exhaust gas flows. The closing portion is provided at an end of the pipe that opens into the interior space and is configured to block the exhaust flow path. The closing portion also has a slit and a cover member. The slit is provided in a wall of the pipe and extends along the wall from a first end to a second end in a direction intersecting the flow direction of the exhaust gas. The cover member has a main body portion and an insertion portion. The main body portion blocks the exhaust flow path. The insertion portion extends from the main body portion and is inserted into the slit.

[0007] In this configuration, the insertion portion overlaps with the slit in the flow direction. Therefore, even if the main body is pushed in the flow direction by the exhaust gas pressure, the insertion portion catches on the wall of the pipe, and movement of the cover member in the flow direction is easily restricted. Therefore, it is possible to prevent the cover member from falling off the pipe due to the exhaust gas pressure.

[0008] In one aspect of the present disclosure, the insertion portion may be formed to extend from near the first end of the slit to near the second end. In this configuration, when the insertion portion is inserted into the slit, the insertion portion substantially abuts against the first and second ends of the slit, which prevents the lid member from rotating in the circumferential direction about the central axis of the pipe relative to the pipe. This prevents the lid member from shifting in the circumferential direction when placed on the pipe.

[0009] In one aspect of the present disclosure, the insertion portion may have a bending portion that protrudes outside the pipe and bends relative to the main body portion. With this configuration, the bent portion can make it difficult for the cover member to come off the pipe easily. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 2 is a cross-sectional view taken along the central axis of the muffler. [Figure 2] FIG. 2 is a perspective view of a cover member and an inlet pipe. [Figure 3] FIG. [Figure 4] Figure 4A is a perspective view of the inlet pipe with the cover member inserted through the first slit, and Figure 4B is a side view of the inlet pipe with the cover member inserted through the first slit. [Figure 5] Fig. 5A is a front view of the downstream end of the inlet pipe with the cover member inserted through the first slit, and Fig. 5B is a cross-sectional view taken along line VB-VB of Fig. 4B. [Figure 6] Fig. 6A is a perspective view showing a state in which the cover member is fixed to the inlet pipe by the bent portion, and Fig. 6B is a side view showing a state in which the cover member is fixed to the inlet pipe by the bent portion. [Figure 7] FIG. 10 is a front view of a cover member according to a first modified example. [Figure 8] FIG. 10 is a front view of a cover member according to a second modified example. [Figure 9] FIG. 11 is a front view of a cover member according to a third modified example. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings. [1. Configuration] The muffler 100 shown in Fig. 1 constitutes part of the exhaust flow path for exhaust gas emitted from an internal combustion engine mounted on a vehicle. The muffler 100 is a device that reduces exhaust noise. The muffler 100 includes an outer shell member 1, a separator 2, an inlet pipe 3, an outlet pipe 4, and a cover member 5.

[0012] <Outer shell material> The outer shell member 1 is a member that forms the internal space and has a side wall 11, a first end plate 12, and a second end plate 13.

[0013] Side wall 11 is a cylindrical member. First end plate 12 and second end plate 13 are arranged to face each other and close openings at both ends of side wall 11. First end plate 12 has a through hole through which inlet pipe 3 passes, and second end plate 13 has a through hole through which outlet pipe 4 passes.

[0014] <Separator> Separator 2 is disposed in the internal space of outer shell member 1 so as to face first end plate 12 and second end plate 13. Separator 2 is fixed to the inner surface of side wall 11 and divides the internal space of outer shell member 1 into a first chamber 14 and a second chamber 15. First chamber 14 is formed between first end plate 12 and separator 2. Second chamber 15 is formed between separator 2 and second end plate 13. Separator 2 has a through hole through which inlet pipe 3 passes and a through hole through which outlet pipe 4 passes. Separator 2 also has a communication hole 21 that connects first chamber 14 and second chamber 15.

[0015] <Inlet pipe> The inlet pipe 3 is, for example, substantially cylindrical, extends along the central axis A, and forms an exhaust flow path through which exhaust gas flows. That is, the cross section of the inlet pipe 3 perpendicular to the central axis A of the exhaust flow path (hereinafter simply referred to as the cross section) is substantially circular. In this embodiment, the diameter of the inlet pipe 3 is substantially constant. The inlet pipe 3 is inserted into the through hole of the first end plate 12 and introduces exhaust gas into the outer shell member 1. The inlet pipe 3 passes through the through hole of the separator 2, and its downstream end 30 opens into the second chamber 15. The inlet pipe 3 has a first slit 31, a second slit 32, and a plurality of through holes 33.

[0016] As shown in FIGS. 1 and 2 , the first slit 31 is provided near the downstream end 30 of the inlet pipe 3. Specifically, the first slit 31 is provided at a position slightly away from the edge of the downstream end 30. The first slit 31 is provided in the wall 301 of the inlet pipe 3 so as to penetrate the wall 301 and extends along the wall 301 from a first end 311 to a second end 312 in a direction intersecting the flow direction of exhaust gas. The flow direction in the inlet pipe 3 coincides with the extension direction of the central axis A. Directions intersecting the flow direction include a direction perpendicular to the central axis A and a direction obliquely intersecting the central axis A. In this embodiment, the first slit 31 extends along the wall 301 of the inlet pipe 3 in a direction perpendicular to the central axis A. In other words, the first slit 31 extends in a circumferential direction around the central axis A.

[0017] The length of the first slit 31 from the first end 311 to the second end 312 is approximately half the circumference of the inlet pipe 3. In other words, the first slit 31 extends approximately halfway around the central axis A. The length of the first slit may be at least half the circumference of the inlet pipe but less than the entire circumference. The width of the first slit 31 in a direction perpendicular to the extension direction (hereinafter simply referred to as the width) is approximately the same as or slightly thinner than the thickness of the cover member 5, which will be described later. In this embodiment, the cover member 5 is inserted through the first slit 31 and placed on the inlet pipe 3. An overlapping portion 52 of the cover member 5, which will be described later, is inserted into the first slit 31.

[0018] The second slit 32 is provided near the downstream end 30 of the inlet pipe 3 so as to be spaced apart from the first slit 31 on a circle that is a part of the arc described by the first slit 31. Specifically, the second slit 32 is provided at a position facing approximately the center of the first slit 31 in the extension direction, centered on the central axis A. The second slit 32 is provided in the wall 301 of the inlet pipe 3 so as to penetrate the wall 301, and extends along the wall 301 in a direction intersecting the flow direction (in this embodiment, a direction perpendicular to the central axis A). The length between both ends of the second slit 32 in the extension direction is shorter than the length of the first slit 31. The width of the second slit 32 is approximately the same as the width of the first slit 31. A second bent portion 54 of the cover member 5, which will be described later, is inserted into the second slit 32.

[0019] 1, the plurality of through holes 33 are provided near the downstream end 30 of the inlet pipe 3 and upstream of the first slit 31 and the second slit 32. Each through hole 33 penetrates the wall 301 of the inlet pipe 3 and connects the internal space of the inlet pipe 3 with the second chamber 15. Note that the plurality of through holes 33 are not shown in FIG.

[0020] <Outlet pipe> The outlet pipe 4 is, for example, substantially cylindrical, extends along a central axis, and forms an exhaust flow path through which exhaust gas flows. The outlet pipe 4 is inserted into the through-hole of the second end plate 13 and discharges the exhaust gas introduced into the outer shell member 1. The outlet pipe 4 passes through the through-hole of the separator 2, and its upstream end 40 opens into the first chamber 14. The outlet pipe 4 is configured so that the upstream end 40 expands in diameter. However, the outlet pipe may be configured so that the upstream end does not expand in diameter and has a substantially constant diameter.

[0021] <Cover parts> The cover member 5 is a flat plate-like member having a substantially uniform thickness. The thickness of the cover member 5 may be thin or thick. However, the thickness of the cover member does not have to be substantially uniform. In this embodiment, the cover member 5 is inserted through the first slit 31 and positioned near the downstream end 30 of the inlet pipe 3. The cover member 5 is configured to overlap the exhaust flow path of the inlet pipe 3 and the slits 31 and 32 in the flow direction. This causes the downstream end 30 of the inlet pipe 3 to be blocked by the cover member 5. In other words, the first slit 31 and second slit 32 of the inlet pipe 3 and the cover member 5 form a closed section that blocks the exhaust flow path of the inlet pipe 3. In this embodiment, the cover member 5 blocks the entire cross-sectional area of ​​the exhaust flow path of the inlet pipe 3.

[0022] As shown in FIG. 3, the cover member 5 has a main body portion 51, an overlapping portion 52, a first bent portion 53, and a second bent portion . The main body 51 is a flat plate-shaped portion that is disposed in the exhaust flow path of the inlet pipe 3 and closes the exhaust flow path. The main body 51 has the same shape as the cross-sectional shape of the exhaust flow path of the inlet pipe 3. As an example, the main body 51 is substantially circular, and has substantially the same diameter as the circular cross-section of the exhaust flow path of the inlet pipe 3.

[0023] The overlapping portion 52 is a flat portion inserted into the first slit 31 and overlaps with the first slit 31 in the flow direction. That is, the overlapping portion 52 overlaps with the wall 301 of the inlet pipe 3 that constitutes the first slit 31 in the flow direction. The overlapping portion 52 extends radially outward from the main body portion 51, from near the first end 311 of the first slit 31 to near the second end 312. That is, the overlapping portion 52 is provided along the edge of the main body portion 51, over approximately half the circumference. Here, the radial direction refers to a direction that passes through the central axis of the main body portion 51 and extends along the plane of the main body portion 51.

[0024] The first bent portion 53 and the second bent portion 54 are flat portions that protrude outward from the inlet pipe 3 and bend relative to the main body portion 51. Each bent portion 53, 54 is used to secure the cover member 5 to the inlet pipe 3. The first bent portion 53 extends radially outward from the overlapping portion 52. The second bent portion 54 extends radially outward from the main body portion 51 so as to protrude outward from the inlet pipe 3 by the same amount as the first bent portion 53. Each bent portion 53, 54 has a radial length longer than the overlapping portion 52 and a circumferential length shorter than the overlapping portion 52. The second bent portion 54 is formed to extend to near both ends of the second slit 32 in the extension direction. In this embodiment, the first bent portion 53 and the second bent portion 54 are positioned radially opposite each other on the main body portion 51. Specifically, the first bent portion 53 is located approximately in the circumferential center of the overlapping portion 52. The second bent portion 54 is located approximately in the center in the circumferential direction of the edge of the main body portion 51 where the overlapping portion 52 is not formed. The second bent portion 54 is inserted into the second slit 32, and its base portion overlaps the second slit 32, i.e., the wall 301 of the inlet pipe 3 that constitutes the second slit 32, in the flow direction.

[0025] 4A to 5B, when main body 51 is disposed in the exhaust flow path of inlet pipe 3, the edge of main body 51 in the portion where overlapping portion 52 and second bent portion 54 are not provided substantially abuts against the inner circumferential surface of inlet pipe 3. Note that "substantially abutting" means that the two portions are abutting or are disposed with a small gap between them.

[0026] When inserted into the first slit 31, the overlapping portion 52 substantially abuts against the first end 311, the second end 312, and both widthwise ends of the first slit 31. In this embodiment, the overlapping portion 52 extends slightly outward beyond the outer circumferential surface of the inlet pipe 3. In other words, the radial length of the overlapping portion 52 is slightly longer than the thickness of the wall 301 of the inlet pipe 3.

[0027] The first bent portion 53 protrudes to the outside of the inlet pipe 3 when the overlapping portion 52 is inserted into the first slit 31 . When inserted into the second slit 32, the second bent portion 54 protrudes outside the inlet pipe 3, and its base portion substantially abuts both ends of the second slit 32 in the extension direction and both ends in the width direction.

[0028] 6A and 6B, after the cover member 5 is inserted through the first slit 31 and placed on the inlet pipe 3, each of the bent portions 53, 54 is bent relative to the main body portion 51. In this embodiment, each of the bent portions 53, 54 is bent at approximately 90° relative to the main body portion 51 and extends along the wall 301 of the inlet pipe 3. Note that the angle at which each bent portion is bent relative to the main body portion may be less than 90°.

[0029] In this embodiment, each of the bent portions 53, 54 is bent so as to extend in the direction opposite to the downstream end 30 of the inlet pipe 3. Note that each of the bent portions may be bent so as to extend toward the downstream end 30 of the inlet pipe 3, or may be bent so as to extend in different directions. In the bent state, each of the bent portions 53, 54 may or may not abut against the wall 301 (in other words, the outer peripheral surface of the inlet pipe 3).

[0030] As shown by the arrows in Figure 1, exhaust gas from the internal combustion engine passes through inlet pipe 3 and is introduced into second chamber 15 via multiple through-holes 33 formed in inlet pipe 3. The exhaust gas in second chamber 15 is then introduced into first chamber 14 via communication holes 21 formed in separator 2. The exhaust gas in second chamber 15 is then discharged to the outside via outlet pipe 4. In this way, the exhaust gas passes through each of chambers 14, 15 formed by dividing the internal space of outer shell member 1, thereby achieving a silencing effect.

[0031] [2. How to assemble the closing part] First, the cover member 5 is inserted through the first slit 31 so that the second bent portion 54 passes through the first slit 31 first, and is then placed on the inlet pipe 3. At this time, the main body portion 51 is placed in the exhaust flow path of the inlet pipe 3, the overlapping portion 52 is inserted into the first slit 31, and the second bent portion 54 is inserted into the second slit 32. Thereafter, the bent portions 53, 54 are bent relative to the main body portion 51, thereby fixing the cover member 5 to the inlet pipe 3. As a result, the exhaust flow path of the inlet pipe 3 is closed by the cover member.

[0032] The bending of each bent portion 53, 54 may be performed at the same timing as the step of press-fitting the separator 2 and the inlet pipe 3 with the cover member 5 disposed thereon into the side wall 11, for example, by taking into consideration the placement of a jig or the like used for the bending. Furthermore, for example, the bending of each bent portion 53, 54 may be performed in a step separate from the above-mentioned press-fitting step.

[0033] [3.Effects] According to the embodiment described above in detail, the following effects can be obtained. (3a) In this embodiment, the overlapping portion 52 of the cover member 5 disposed on the inlet pipe 3 overlaps with the first slit 31 in the flow direction, and the root portion of the second bent portion 54 overlaps with the second slit 32 in the flow direction. Therefore, even if the main body portion 51 is pushed in the flow direction by the pressure of the exhaust gas, the overlapping portion 52 and the root portion of the second bent portion 54 are caught on the wall 301 of the inlet pipe 3, and movement of the cover member 5 in the flow direction is likely to be restricted. Therefore, it is possible to prevent the cover member 5 from falling off the inlet pipe 3 due to the pressure of the exhaust gas.

[0034] (3b) In this embodiment, the overlapping portion 52 is formed to extend from near the first end 311 of the first slit 31 to near the second end 312. In other words, when inserted into the first slit 31, the overlapping portion 52 substantially abuts against the first end 311 and the second end 312 of the first slit 31. This prevents the cover member 5 from rotating in the circumferential direction relative to the inlet pipe 3. This prevents the cover member 5 from being displaced in the circumferential direction when placed on the inlet pipe 3.

[0035] (3c) In this embodiment, the overlapping portion 52 extends from near the first end 311 of the first slit 31 to near the second end 312, and the width of the first slit 31 is approximately the same as or slightly thinner than the thickness of the cover member 5 (i.e., the thickness of the overlapping portion 52). In other words, when inserted into the first slit 31, the overlapping portion 52 approximately abuts against the first end 311, the second end 312, and both widthwise ends of the first slit 31.

[0036] Furthermore, the second bent portion 54 extends to the vicinity of both ends of the second slit 32 in the extension direction, and the width of the second slit 32 is approximately the same as or slightly thinner than the thickness of the cover member 5 (i.e., the thickness of the second bent portion 54). In other words, when inserted into the second slit 32, the base portion of the second bent portion 54 approximately abuts both ends of the second slit 32 in the extension direction and both ends in the width direction.

[0037] As a result, the first slits 31 are easily blocked by the overlapping portions 52, and the second slits 32 are easily blocked by the second bent portions 54. Therefore, leakage of exhaust gas from the first slits 31 and the second slits 32 can be suppressed.

[0038] (3d) In this embodiment, the cover member 5 has a first bent portion 53 and a second bent portion 54, and each bent portion 53, 54 is bent relative to the main body portion 51 after the cover member 5 is inserted through the first slit 31 and placed on the inlet pipe 3. Therefore, the first bent portion 53 and the second bent portion 54 make it difficult for the cover member 5 to easily come off the inlet pipe 3. In other words, the cover member 5 can be easily fixed to the inlet pipe 3.

[0039] (3e) In this embodiment, the first slit 31 extends approximately halfway around the central axis A. This makes it easy to insert and remove the cover member 5 into and from the first slit 31. This makes it easy to attach the cover member 5 to the inlet pipe 3.

[0040] In this embodiment, the through hole of first end plate 12 corresponds to an example of an opening in an outer shell member, inlet pipe 3 corresponds to an example of a pipe, and downstream end 30 corresponds to an example of an end that opens into the internal space of a pipe. Also, first slit 31 and second slit 32 correspond to an example of a slit, overlapping portion 52 and at least the base portion of second bent portion 54 correspond to an example of an insertion portion, and first bent portion 53 and second bent portion 54 correspond to an example of a bent portion.

[0041] 4. 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.

[0042] (4a) In the above embodiment, the cover member 5 has two bent portions, the first bent portion 53 and the second bent portion 54, and the first bent portion 53 and the second bent portion 54 are arranged in positions that face each other in the radial direction of the main body portion 51. However, the configuration of the cover member is not limited to this. For example, the first bent portion and the second bent portion of the cover member may be arranged in positions that do not face each other in the radial direction of the main body portion.

[0043] Furthermore, for example, the number of bent portions that the lid member has may be one or three or more. For example, as shown in FIG. 7, the lid member 5a of a first modified example may have a main body portion 51a, an overlapping portion 52a, and a second bent portion 54a. That is, the lid member 5 of the above embodiment may have a configuration that does not have the first bent portion 53. The configuration of the lid member 5a of the first modified example also provides the same effects as those of the above embodiment (3a) to (3c). Furthermore, the second bent portion 54a alone can make it difficult for the lid member 5 to easily come off the inlet pipe 3.

[0044] 8, the cover member 5b of the second modified example may have two other bent portions 55 in addition to the main body portion 51b, the overlapping portion 52b, the first bent portion 53b, and the second bent portion 54b. The two other bent portions 55 extend radially outward from the overlapping portion 52 and are arranged on both sides of the first bent portion 53b in the circumferential direction with a gap therebetween. The configuration of the cover member 5b of the second modified example also provides the same effects as those of the above-described embodiment (3a) to (3c). Furthermore, the first bent portion 53b, the second bent portion 54b, and the two other bent portions 55 can more firmly fix the cover member 5 to the inlet pipe 3.

[0045] Additionally, for example, the cover member may not have a bent portion. In this case, when the muffler is mounted on the vehicle, the inlet pipe is positioned on the muffler so that the first slit with the overlapping portion inserted faces vertically upward. Even if the cover member does not have a bent portion, the overlapping portion inserted into the first slit tends to restrict movement of the cover member in the flow direction. Therefore, it is possible to prevent the cover member from falling off the inlet pipe due to exhaust gas pressure.

[0046] (4b) In the above embodiment, the first bent portion 53 and the second bent portion 54 are configured to protrude outside the inlet pipe 3 and bend relative to the main body portion 51, but the configuration of the bent portions is not limited to this. For example, the bent portions may be configured to protrude outside the inlet pipe and not bend relative to the main body portion.

[0047] Furthermore, for example, the bent portion does not have to protrude outside the inlet pipe. Specifically, for example, the bent portion may be configured to extend from the main body by a length approximately equal to the thickness of the wall of the inlet pipe when inserted into the slit. For example, the bent portion may be configured to be located outside the inner circumferential surface of the inlet pipe and inside the outer circumferential surface of the inlet pipe when inserted into the slit.

[0048] Additionally, the second bent portion 54 extends to the vicinity of both ends in the extension direction of the second slit 32. However, for example, the second bent portion may extend along the edge of the main body portion in an aspect in which the length is shorter than the length between both ends in the extension direction of the second slit.

[0049] (4c) In the above embodiment, the overlapping portion 52 extends from near the first end 311 of the first slit 31 to near the second end 312 and extends slightly outward from the outer circumferential surface of the inlet pipe 3. However, the configuration of the overlapping portion is not limited to this. For example, the overlapping portion may extend along the edge of the main body portion, but in a manner shorter than the length from the first end to the second end of the first slit. Furthermore, for example, the overlapping portion does not have to extend outward from the inlet pipe. Specifically, for example, the overlapping portion may extend from the main body portion by a length approximately equal to the thickness of the wall of the inlet pipe when inserted into the first slit. Furthermore, for example, the overlapping portion may be configured to be located outward from the inner circumferential surface of the inlet pipe and inward from the outer circumferential surface of the inlet pipe when inserted into the first slit.

[0050] (4d) In the above embodiment, the cover member 5 is fixed to the inlet pipe 3 by the bent portions 53, 54 bent relative to the main body portion 51. However, the method for fixing the cover member is not limited to this. For example, the cover member and the inlet pipe may be fixed by welding. In this case, welds are provided at the overlapping portions and bent portions that are inserted into the slits of the inlet pipe. Examples of welding methods include spot welding and MIG welding. Alternatively, for example, the cover member 5 may be slightly thicker than the slits, and the cover member 5 may be press-fitted into the inlet pipe along the slits, i.e., along a direction intersecting the flow direction.

[0051] (4e) In the above embodiment, the cover member 5 covers the entire cross-sectional area of ​​the exhaust flow passage of the inlet pipe 3. However, the cover member may be configured to cover only a portion of the cross-sectional area of ​​the exhaust flow passage of the inlet pipe 3. That is, the cover member may have the exhaust flow passages on the upstream and downstream sides of the cover member communicate with each other over a portion of the cross-sectional area. For example, as shown in FIG. 9 , a cover member 5c of a third modified example may have a main body portion 51c with a through hole 56, an overlapping portion 52c, a first bent portion 53c, and a second bent portion 54c. Note that the position of the through hole in the main body portion may be other than approximately the center of the main body portion, as long as it overlaps the cross-sectional area of ​​the flow passage in the flow direction.

[0052] (4f) In the above embodiment, the first slit 31 and the second slit 32 extend along the wall 301 of the inlet pipe 3 in a direction that intersects with the central axis A and is perpendicular to the central axis A. However, for example, the first slit and the second slit may extend along the wall of the inlet pipe, intersecting the central axis A at an angle.

[0053] (4g) In the above embodiment, the cross-sectional shape of the exhaust flow path of the inlet pipe 3 is approximately circular, and the main body 51 is also approximately circular. However, for example, the cross-sectional shape of the exhaust flow path of the inlet pipe and the shape of the main body may be elliptical or polygonal. It is preferable that the cross-sectional shape of the exhaust flow path of the inlet pipe and the shape of the main body are the same shape.

[0054] (4h) In the above embodiment, the closed portion is provided near the downstream end 30 of the inlet pipe 3, but the pipe on which the closed portion is provided is not limited to the inlet pipe. For example, the closed portion may be provided near the upstream end of the outlet pipe. Also, for example, the closed portion may be provided in the inner pipe of a double-wrapped muffler.

[0055] (4i) The function of one component in the above embodiments may be distributed among multiple components, or the functions of multiple components may be integrated into one component. Also, part of the configuration of the above embodiments may be omitted. Furthermore, 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. [Explanation of symbols]

[0056] 1...outer shell member, 2...separator, 3...inlet pipe, 4...outlet pipe, 5, 5a to 5c...cover member, 11...side wall, 12...first end plate, 13...second end plate, 14...first chamber, 15...second chamber, 21...communicating hole, 30...downstream end, 31...first slit, 32...second slit, 33, 56...through hole, 40...upstream end, 51, 51a to 51c...main body portion, 52, 52a to 52c...overlapping portion, 53, 53b, 53c...first bent portion, 54, 54a to 54c...second bent portion, 55...other bent portion, 100...muffler, 301...wall, 311...first end, 312...second end, A...central axis.

Claims

1. A muffler mounted on a vehicle, an outer shell member that forms an internal space; a pipe inserted into the opening of the outer shell member to form an exhaust flow path through which exhaust gas flows; a closing portion provided at an end of the pipe that opens into the internal space and configured to close the exhaust flow path; Equipped with The closing portion is a slit provided in a wall of the pipe and extending along the wall from a first end to a second end in a direction intersecting the flow direction of the exhaust gas; A muffler comprising: a cover member having a main body portion that closes the exhaust flow path; and an insertion portion that extends from the main body portion and is inserted into the slit.

2. 2. The muffler of claim 1, The muffler is configured such that the insertion portion extends from near the first end of the slit to near the second end.

3. The muffler according to claim 1 or 2, The insertion portion protrudes outside the pipe and has a bent portion that bends relative to the main body portion.

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