scarf

Abstract

To suppress vibration of a muffler.SOLUTION: A muffler includes: a shell having a cylindrical side wall extending along an axis; an inlet pipe; and a stay having first and second wall parts. The first wall part has a hole part through which the inlet pipe penetrates, and is joined to the side wall. The second wall part extends from an end part of the first wall part, and includes an abutment part and a reinforcement part. The abutment part abuts on an abutment region that is a region on an inner peripheral surface of the side wall, the region extending in a circumferential direction that is a direction approximately orthogonal to the axis and along the inner peripheral surface, and is joined to the abutment region. The reinforcement part is provided in the abutment part in the circumferential direction and reinforces the abutment part.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to a muffler.

Background Art

[0002] As described in Patent Document 1, a technique is known in which a stay, which is a plate-like member that supports an inlet pipe, is provided inside the shell of a muffler. The cylindrical side wall of the shell has an oval cross-section, and includes two small R portions that are portions extending in the short direction of the cross-section and two large R portions that are portions extending in the long direction of the cross-section. The inlet pipe protrudes obliquely upward into the shell from a hole provided in the small R portion and penetrates the stay. Both ends of the stay are joined to the small R portion and the large R portion, respectively.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] According to the muffler of Patent Document 1, since the inlet pipe is held by the stay, the vibration of the inlet pipe can be suppressed. However, since the exhaust gas discharged from the inlet pipe collides with the shell, the shell may vibrate due to pulsation of the exhaust gas or the like.

[0005] In one aspect of the present disclosure, it is desirable to suppress the vibration of the muffler.

Means for Solving the Problems

[0006] One aspect of the present disclosure is a muffler configured for mounting on a vehicle, comprising a shell, an inlet pipe, and a stay. The shell has a cylindrical side wall extending along an axis and plates closing both ends of the side wall. The inlet pipe is provided so as to protrude into the interior of the shell from an exhaust gas inlet provided in the side wall. The stay supports the inlet pipe. The stay also comprises a first wall portion and a second wall portion. The first wall portion is a plate-like portion having a hole through which the inlet pipe passes and is joined to the side wall. The second wall portion is a plate-like portion extending from the end of the first wall portion. The second wall portion also comprises a contact portion and a reinforcing portion. The contact portion is a region on the inner circumferential surface of the side wall that abuts against and is joined to the contact region, which is a region extending in the circumferential direction that is substantially perpendicular to the axis and along the inner circumferential surface. The reinforcing portion is provided on the contact portion along the circumferential direction and reinforces the contact portion.

[0007] According to the above configuration, the contact portion, reinforced by the reinforcing portion, contacts the inner circumferential surface of the shell's side wall, thereby improving the rigidity of the side wall. Consequently, muffler vibration can be suppressed. In one aspect of this disclosure, the cross-section perpendicular to the axis in the side wall may have a shape extending in the longitudinal direction. The portion of the side wall extending along the longitudinal direction may be a large radius portion. The contact region may be provided in the large radius portion.

[0008] With the above configuration, the contact portion reinforced by the reinforcing portion abuts against the inner surface of the large radius portion on the side wall of the shell, thereby effectively improving the rigidity of the side wall. Consequently, muffler vibration can be suppressed even further.

[0009] In one aspect of this disclosure, the reinforcing portion may include two wall-like portions facing each other in the axial direction. The above configuration effectively improves the rigidity of the side walls. Therefore, muffler vibration can be suppressed even further.

[0010] In one aspect of this disclosure, the reinforcing portion may be a wall-like portion that protrudes inward from both ends in the axial direction of the contact portion toward the interior of the shell. The above configuration effectively improves the rigidity of the side walls. Therefore, muffler vibration can be suppressed even further. [Brief explanation of the drawing]

[0011] [Figure 1] This is a perspective view of the muffler according to the first embodiment. [Figure 2] This is a perspective view showing the internal structure of the muffler according to the first embodiment. [Figure 3] This is a cross-sectional view of the muffler of the first embodiment, perpendicular to the axis in the second region. [Figure 4] This is a perspective view of the stay of the first embodiment. [Figure 5] This is a cross-sectional view of the second wall portion of the stay in the first embodiment, perpendicular to the extension direction (in other words, the circumferential direction). [Figure 6] This is an explanatory diagram of the vibration modes in the muffler of the first embodiment. [Figure 7] This is a perspective view of the stay of the second embodiment. [Figure 8] This is a cross-sectional view of the second wall portion of the stay in the second embodiment, perpendicular to the extension direction. [Figure 9] This is a perspective view of the stay of the third embodiment. [Figure 10] This is a perspective view of the stay of the fourth embodiment. [Figure 11] This is a perspective view of the stay of the fifth embodiment. [Modes for carrying out the invention]

[0012] The embodiments of this disclosure will be described below with reference to the drawings. However, the embodiments of this disclosure are not limited to those described below, and various forms may be taken as long as they fall within the technical scope of this disclosure.

[0013] [1. First Embodiment] [(1) Overview] The muffler 1 of the first embodiment is mounted on a vehicle and provided in the exhaust gas flow path from the engine of the vehicle (see FIGS. 1 to 3). The muffler 1 is connected to one upstream pipe 30 and two downstream pipes 31. When the exhaust gas passing through the upstream pipe 30 flows into the muffler 1, the exhaust gas passing through the muffler 1 flows into each downstream pipe 31. Of course, this is not the only case, and one downstream pipe may be connected to the muffler 1. The muffler 1 includes a shell 10, an inlet pipe 14, first to third separators 15, two internal pipes 16, and a stay 2.

[0014] [(2) Shell] The shell 10 includes a cylindrical side wall 11 extending along the axis 1A and two end plates 12 closing the openings at both ends of the side wall 11 (see FIGS. 1 to 3).

[0015] The cross section (hereinafter simply referred to as the cross section) of the side wall 11 orthogonal to the axis 1A has an elongated shape extending in the longitudinal direction (for example, an elliptical shape). In the first embodiment, as an example, the muffler 1 is mounted on the vehicle such that the short direction orthogonal to the longitudinal direction in the cross section coincides with the vertical direction. Of course, this is not the only case, and the cross section of the side wall 11 may be, for example, an oval shape or a rectangular shape. Further, the orientation of the muffler 1 when mounted on the vehicle is not limited to the above, and the muffler 1 may be mounted on the vehicle such that, for example, the longitudinal direction coincides with the vertical direction.

[0016] Hereinafter, the portion of the side wall 11 extending along the longitudinal direction will be described as the large R portion 11A, and the portion extending along the short direction will be described as the small R portion 11B. In other words, the large R portion 11A is a portion where the radius of curvature in the cross section of the side wall 11 is large, and the small R portion 11B is a portion where the radius of curvature in the cross section is small. The side wall 11 includes two large R portions 11A facing the short direction and two small R portions 11B facing the longitudinal direction.

[0017] Furthermore, an exhaust gas inlet 13 into the muffler 1 is provided in the portion of the small radius section 11B of the side wall 11 adjacent to one of the large radius sections 11A. For example, the inlet 13 is located adjacent to the lower large radius section 11A in the small radius section 11B and faces diagonally downward. In addition, a wall section 13A is provided at the edge of the inlet 13 in the side wall 11, surrounding the inlet 13 and projecting outward. The end of the upstream pipe 30 is connected to the inlet 13.

[0018] On the other hand, each end plate 12 is provided with an exhaust gas outlet, and the end of the downstream pipe 31 described above is connected to each outlet. [(3) Separator and internal pipes] The separator 15 is a plate-shaped member that partitions the internal space of the muffler 1 and is installed perpendicular to the axis 1A (see Figures 2 and 3). In the first embodiment, as an example, three separators 15 are provided, and the internal space of the muffler 1 is divided into first to fourth regions 1B to 1E by these separators 15.

[0019] Each separator 15 is provided with a hole 15A, and exhaust gas from each region 1B to 1E passes through the hole 15A to move to other regions. Of course, the number and arrangement of the holes 15A are not limited to these and can be determined as appropriate.

[0020] Furthermore, two internal pipes 16 are arranged within the internal space of the muffler 1, extending in the direction of the axis 1A. The first end of each internal pipe 16 is connected to the outlet of each end plate 12, and through this outlet it is connected to the downstream pipe, and it also extends from this outlet through each separator 15. The second end of each internal pipe 16 is located in the first and fourth regions 1B and 1E, respectively, adjacent to each end plate 12. That is, the first region 1B and the fourth region 1E are spaces enclosed by the side wall 11, the end plate 12, and the separator 15. The second region 1C and the third region 1D are spaces enclosed by the side wall 11 and the adjacent separator 15.

[0021] Of course, the number of separators 15 and the number and arrangement of internal pipes 16 are not limited to these and can be determined as appropriate. Furthermore, the muffler 1 may be configured without separators 15 and / or internal pipes 16. Also, the internal pipes 16 and the downstream pipe 31 may be formed as a single pipe.

[0022] [(4) Inlet pipe] The exhaust gas inlet 13, provided in the side wall 11 of the shell 10, is positioned to face the second region 1C (see Figures 2 and 3). The inlet pipe 14 is provided so as to project into the second region 1C toward the large R portion 11A located on the opposite side of the large R portion 11A adjacent to the inlet 13. In the first embodiment, as an example, since the inlet 13 is provided adjacent to the lower large R portion 11A, the inlet pipe 14 projects diagonally upward toward the upper large R portion 11A.

[0023] The inlet pipe 14 is, for example, substantially cylindrical and extends in a straight line. The openings at both ends of the inlet pipe 14 spread out in a planar direction perpendicular to the extension direction of the inlet pipe 14. The first end of the inlet pipe 14 is joined to the wall portion 13A of the inlet 13. The joining described herein can be achieved by various methods, including, for example, welding. On the other hand, the opening at the second end of the inlet pipe 14 is located in the second region 1C and forms an outlet 14A for releasing exhaust gas that has passed through the inlet pipe 14.

[0024] [(5) Stay] The stay 2 is positioned in the second region 1C inside the muffler 1 and supports the inlet pipe 14 (see Figures 2-5). The stay 2 is manufactured by deforming a single plate-shaped base material, for example, by press molding. The stay 2 comprises a first wall portion 20, which is a roughly rectangular plate-shaped portion, and a second wall portion 23, which is a plate-shaped portion extending from the end of the first wall portion 20. The stay 2 is bent in an L-shape at the boundary between the first wall portion 20 and the second wall portion 23, and the first and second wall portions 20 and 23 spread out in the direction of the axis 1A.

[0025] The first wall portion 20 is inclined with respect to its shorter side and faces the entrance 13. The first wall portion 20 includes a centrally located hole portion 21 and a joint portion 22. The edge of the first wall portion 20 surrounding the hole portion 21 is provided with a wall portion 21A that protrudes toward the outlet 14A side of the inlet pipe 14. For example, the wall portion 21A may be formed by burring. The inlet pipe 14 is provided in a state where it passes through the hole portion 21 and is supported by the wall portion 21A in a slidable state. The wall portion 21A may also protrude toward the inlet 13 side.

[0026] The joint portion 22 is an elongated portion located at the lower end of one side of the first wall portion 20, in other words, at the end opposite the second wall portion 23, and extends along the axis 1A. The joint portion 22 is formed by bending the aforementioned end of the first wall portion 20. The joint portion 22 is joined to the lower large radius portion 11A, for example, by welding.

[0027] [(6) Second wall section] The second wall portion 23 of the stay 2 comprises a base portion 24, an extension portion 25, and a reinforcing portion 26 (see Figures 2-5).

[0028] The base portion 24 extends circumferentially from an end portion that forms one side located on the upper side of the first wall portion 20. The circumferential direction is the direction along the inner circumferential surface of the side wall 11 in the cross-section of the side wall 11, and is approximately perpendicular to the axis 1A. The width of the base portion 24 narrows as it moves away from the aforementioned end portion of the first wall portion 20. When viewed from above, the base portion 24 is approximately triangular. Of course, the base portion 24 is not limited to being approximately triangular; for example, it may be quadrilateral.

[0029] The extension portion 25 extends circumferentially from the center of the end of the base portion 24 opposite to the first wall portion 20. More specifically, the extension portion 25 extends from the portion of the base portion 24 that includes the vertices forming a roughly triangular shape. In other words, the extension portion 25 extends from the end of the base portion 24 opposite to the first wall portion 20. The extension portion 25 is a band-shaped portion with a roughly constant width.

[0030] The reinforcing portion 26 is provided at both ends of the base portion 24 and the extension portion 25 in the width direction (in other words, in the direction of axis 1A), and is a wall-like portion that protrudes toward the internal space of the muffler 1, and has portions facing each other in the width direction (see Figure 5). The reinforcing portion 26 extends along the base portion 24 and the extension portion 25 (in other words, along the circumferential direction) from near the first wall portion 20 of the base portion 24 to the tip of the extension portion 25. Note that the reinforcing portion 26 may be provided only at one end of the base portion 24 and the extension portion 25 in the width direction.

[0031] The base portion 24 and the extension portion 25 form a contact portion that abuts against the inner circumferential surface of the side wall 11 over almost their entire area. The contact region with the contact portion on the inner circumferential surface of the side wall 11 is an elongated region extending in the circumferential direction. As an example, the base portion 24 and the extension portion 25 are joined to the inner circumferential surface of the side wall 11 by spot welding at multiple locations located approximately in the center in the width direction. Of course, the positions where the base portion 24 and the extension portion 25 are joined to the side wall 11 are not limited to approximately in the center in the width direction, but can be determined as appropriate. Furthermore, the base portion 24 and the extension portion 25 may be joined to the side wall 11 by welding other than spot welding, or by methods other than welding.

[0032] More specifically, the end of the base 24 on the first wall 20 side is located near the upper large radius 11A of the small radius 11B on the entrance 13 side, and the tip of the extension 25 reaches the vicinity of the small radius 11B where the entrance 13 is not provided in the large radius 11A. In other words, the contact area between the base 24 and the extension 25 is provided in the large radius 11A. Note that this contact area may also be located in the small radius 11B.

[0033] Therefore, the base portion 24 and the extension portion 25 abut, for example, the locations where the antinodes of the first to third modes of natural vibration occur in the side wall 11 (see Figure 6). The antinode of the first mode of natural vibration is formed approximately in the circumferential center of the large radius portion 11A. The antinode of the second mode of natural vibration is formed approximately in the circumferential center of each region formed by dividing the large radius portion 11A into two equal parts in the circumferential direction. Furthermore, the antinode of the third mode of natural vibration is formed approximately in the circumferential center of each region formed by dividing the large radius portion 11A into three equal parts in the circumferential direction.

[0034] Of course, this is not the only option; the end of the base 24 on the first wall 20 side may, for example, be located at the boundary between the small radius 11B and the large radius 11A, or near the small radius 11B in the large radius 11A. Furthermore, the tip of the extension 25 may extend, for example, to the boundary between the upper large radius 11A and the small radius 11B where the entrance 13 is not provided, or even further to the small radius 11B. Also, the tip of the extension 25 may be located, for example, approximately in the longitudinal center of the upper large radius 11A (in other words, at the position of the antinode of the first mode's natural vibration), or at the position of the antinode of the second mode's natural vibration located closest to the first wall 20, or at the position of the antinode of the third mode's natural vibration located closest to the first wall 20.

[0035] [2. Second Embodiment] The muffler 1 of the second embodiment differs from that of the first embodiment in the configuration of the second wall portion 4 in the stay 2 (see Figures 7 and 8). The differences between the second wall portion 4 of the second embodiment and that of the first embodiment will be described below.

[0036] The second wall portion 4 is a plate-shaped part and comprises a base portion 40, an extension portion 41, a contact portion 42, a bottom portion 43, and a reinforcing portion 44. Similar to the first embodiment, the base portion 40 extends circumferentially from the upper end of the first wall portion 20 and has a roughly triangular shape when viewed from above.

[0037] The extension portion 41, similar to the first embodiment, is a band-shaped portion that extends circumferentially from the center of the end of the base portion 40 opposite to the first wall portion 20, and has a substantially constant width. The contact portion 42 is provided along the boundary between the base portion 40 and the first wall portion 20, and along the edges that form both ends in the width direction of the base portion 40 and the extension portion 41. The contact portion 42 extends from the end of the base portion 40 on the side of the first wall portion 20 to the tip of the extension portion 41.

[0038] The bottom portion 43 is a recessed area in the base portion 40 and the extension portion 41, and is located inside the contact portion 42. The bottom portion 43 extends circumferentially from the base portion 40 and reaches the tip of the extension portion 41.

[0039] The reinforcing portion 44 is a wall-like portion connecting the contact portion 42 and the bottom portion 43, and is inclined with respect to the inner surface of the side wall 11 such that the cross section perpendicular to the circumferential direction of the portion of the second wall portion 4 where the bottom portion 43 is located becomes a convex shape protruding from the inner surface of the side wall 11 (see Figure 8). In other words, the reinforcing portion 44 is located at both ends in the width direction of the bottom portion 43 and has two wall-like portions facing each other in the width direction. Furthermore, the reinforcing portion 44 extends along the circumferential direction from near the first wall portion 20 of the base portion 24 to the tip of the extension portion 41.

[0040] The contact portion 42 abuts against the inner circumferential surface of the side wall 11 over almost its entire area, and the contact region between the contact portion 42 and the inner circumferential surface of the side wall 11 is an elongated region extending in the circumferential direction. The contact portion 42 is joined to the inner circumferential surface of the side wall 11 by welding (for example, spot welding). Of course, this is not the only method; for example, the contact portion 42 located on one side of the bottom portion 43 may be welded to the side wall 11. Furthermore, the contact portion 42 may be joined to the side wall 11 by methods other than welding.

[0041] In other words, the second wall portion 4 is joined to the side wall 11 with a gap formed between the bottom portion 43 and the reinforcing portion 44 and the inner circumferential surface of the side wall 11. The tip of the extension portion 41 is located at the contact portion 42, the bottom portion 43, and the reinforcing portion 44, and an opening is formed at this tip between the bottom portion 43 and the reinforcing portion 44 and the side wall 11.

[0042] [3. Third Embodiment] The muffler 1 of the third embodiment differs from the second embodiment in the configuration of the second wall portion 4 in the stay 2, more specifically in the fact that the second wall portion 4 is provided with two bottom portions 43 (see Figure 9). The differences between the second wall portion 4 of the third embodiment and the second embodiment will be described below.

[0043] The second wall portion 4 is a rectangular plate-like section that extends circumferentially from the upper end of the first wall portion 20. The second wall portion 4 includes a contact portion 42, two bottom portions 43, and a reinforcing portion 44. Each bottom portion 43, as in the second embodiment, is a recessed portion of the second wall portion 4, extending circumferentially from near the boundary between the second wall portion 4 and the first wall portion 20, and reaching the opposite end (in other words, the tip) of the second wall portion 4 from the first wall portion 20. The two bottom portions 43 are aligned in the width direction of the second wall portion 4.

[0044] The contact portion 42 is provided along the boundary between the second wall portion 4 and the first wall portion 20, and along each edge forming both ends in the width direction of the second wall portion 4, so as to reach the tip of the second wall portion 4. In addition, the contact portion 42 is provided between the two bottom portions 43 so as to reach the tip of the second wall portion 4.

[0045] The reinforcing portion 44 connects the contact portion 42 and the bottom portion 43 in the same manner as in the second embodiment and has a plurality of wall-like portions facing each other in the width direction. Similar to the second embodiment, the contact portion 42 abuts against the inner circumferential surface of the side wall 11 over almost its entire area, and the contact region between the contact portion 42 and the inner circumferential surface of the side wall 11 is an elongated region extending in the circumferential direction. Furthermore, the contact portion 42 is joined to the inner circumferential surface of the side wall 11 in the same manner as in the second embodiment.

[0046] In other words, a gap is formed between the two bottom portions 43 and reinforcing portion 44 of the second wall portion 4 and the inner circumferential surface of the side wall 11, and at the tip of the second wall portion 4, two openings are formed between the two bottom portions 43 and reinforcing portion 44 and the side wall 11.

[0047] [4. Fourth Embodiment] The muffler 1 of the fourth embodiment differs from that of the second embodiment in the configuration of the second wall portion 4 in the stay 2 (see Figure 10). The differences between the second wall portion 4 of the fourth embodiment and that of the second embodiment will be described below.

[0048] The second wall portion 4 is a plate-shaped part and includes a base portion 40, an extension portion 41, a contact portion 42, a bottom portion 43, and a reinforcing portion 44, similar to the second embodiment. However, the second wall portion 4 is configured to form a sound-absorbing chamber 4A between itself and the inner circumferential surface of the side wall 11, and the configuration of the portion around the tip of the extension portion 41 differs from that of the second embodiment.

[0049] In other words, the bottom portion 43 and the reinforcing portion 44 do not reach the tip of the extension portion 41, and the tip of the extension portion 41 is formed by the contact portion 42. Therefore, the contact area with the contact portion 42 on the inner circumferential surface of the side wall 11 is an elongated region extending in the circumferential direction.

[0050] Furthermore, the second wall portion 4 is joined to the side wall 11 with a gap formed between the bottom portion 43 and the reinforcing portion 44 and the inner circumferential surface of the side wall 11, similar to the second embodiment, but the tip of the extension portion 41 is closed by the contact portion 42 and the reinforcing portion 44. As a result, the gap is isolated from the internal space of the muffler 1, and the gap can function as a sound-absorbing chamber 4A. In addition, the bottom portion 43 has a plurality of holes 43A that penetrate the bottom portion 43 and are arranged in the circumferential direction. The holes 43A communicate the inside and outside of the sound-absorbing chamber 4A.

[0051] Furthermore, sound-absorbing material 4B is placed in the sound-absorbing chamber 4A as an example. However, the configuration is not limited to this, and the sound-absorbing chamber 4A may be configured without sound-absorbing material 4B. In this case, sound dampening is promoted in the sound-absorbing chamber 4A due to interference, resonance, etc.

[0052] [5. Fifth Embodiment] The muffler 1 of the fifth embodiment differs from that of the fourth embodiment in the configuration of the second wall portion 4 in the stay 2 (see Figure 11). The differences between the second wall portion 4 of the fifth embodiment and that of the fourth embodiment will be described below.

[0053] The second wall portion 4 is a rectangular plate-like portion that extends circumferentially from the upper end of the first wall portion 20. The second wall portion 4 includes a contact portion 42, a bottom portion 43, and a reinforcing portion 44. The contact portion 42 is provided so as to encircle the edge of the second wall portion 4. In other words, the contact portion 42 is provided along the boundary between the second wall portion 4 and the first wall portion 20, and also along the end of the second wall portion 4 opposite to the first wall portion 20. Furthermore, the contact portion 42 is provided along each edge that forms both ends in the width direction of the second wall portion 4. As a result, the contact area with the contact portion 42 on the inner circumferential surface of the side wall 11 forms an elongated region extending in the circumferential direction.

[0054] The bottom portion 43 is a recessed rectangular area in the second wall portion 4 and is located inside the contact portion 42. In addition, the bottom portion 43 has multiple holes 43A that penetrate through it. The reinforcing portion 44 connects the contact portion 42 and the bottom portion 43 in the same manner as in the third embodiment and has a plurality of wall-like portions facing each other in the width direction.

[0055] In other words, the second wall portion 4 of the fifth embodiment is configured to form a sound-absorbing chamber 4A between itself and the inner circumferential surface of the side wall 11, similar to the fourth embodiment. However, the shape of the bottom portion 43 of the second wall portion 4 of the fifth embodiment differs from that of the fourth embodiment, forming a wider sound-absorbing chamber 4A than in the fourth embodiment.

[0056] Furthermore, sound-absorbing material 4B is placed in the sound-absorbing chamber 4A as an example. However, the configuration is not limited to this, and the sound-absorbing chamber 4A may be configured without placing sound-absorbing material 4B. [6. Effects] (1) According to the above embodiment, the base portion 24, the extension portion 25, and the contact portion 42 of the second wall portion of the stay 2 are reinforced by the reinforcing portions 26 and 44, so that the second moment of area is improved and deformation is made difficult. Furthermore, since these reinforced portions are in surface contact with the inner circumferential surface of the side wall 11 of the shell 10, the rigidity of the side wall 11 is improved. Therefore, even when pulsation occurs in the exhaust gas, vibration of the muffler 1 can be suppressed, and thereby the generation of radiated noise in the muffler 1 can be suppressed.

[0057] (2) Furthermore, the base portion 24, the extension portion 25, and the contact portion 42 are in surface contact with the large radius portion 11A of the side wall 11, which is prone to deformation. As a result, deformation of the large radius portion 11A can be suppressed, and the rigidity of the side wall 11 can be effectively improved, thereby further suppressing vibration of the muffler 1.

[0058] (3) Furthermore, since the circumferentially extending extension portion 25 and the contact portion 42 are configured to make surface contact with the large radius portion 11A, these portions can contact the antinodes of multiple vibration modes in the large radius portion 11A. For this reason, various vibration modes in the side wall 11 can be suppressed with a relatively simple configuration without excessively increasing the portion that makes surface contact with the large radius portion 11A. In addition, this makes it possible to reduce the sound pressure level of the radiated sound generated by the muffler 1 compared to conventional designs.

[0059] (4) Furthermore, the reinforcing portions 26 and 44 are wall-like portions facing each other in the width direction (in other words, in the direction of axis 1A). In addition, in the first embodiment, the reinforcing portion 26 protrudes inward from both ends of the base portion 24 and extension portion 25 in the width direction toward the interior of the shell 10. This allows for a favorable improvement of the second moment of area at the contact portion 42 and the base portion 24 and extension portion 25, and as a result, the rigidity of the side wall 11 can be effectively improved. Therefore, vibration of the muffler 1 can be suppressed even further.

[0060] [7. Other Embodiments] (1) In the above embodiment, the cross-section of the side wall 11 of the shell 10 is elongated, but it is not limited to this, and the cross-section may be circular or a regular polygon, for example.

[0061] (2) In the above embodiment, the exhaust gas inlet 13 and the stay 2 are located in the second region 1C in the internal space of the muffler 1. However, the exhaust gas inlet 13 and the stay 2 may also be located in the first, third, or fourth regions 1B, 1D, or 1E.

[0062] (3) In the above embodiment, the stay 2 may be manufactured by joining a plurality of members. More specifically, the stay 2 may be manufactured by joining, for example, a member constituting the first wall portion 20 and members constituting the second wall portions 23 and 4. This makes it possible to simplify the assembly work of the muffler 1, for example.

[0063] (4) In the above embodiment, the exhaust gas inlet 13 is located in the portion of the small radius portion 11B of the side wall 11 adjacent to the lower large radius portion 11A. However, it is not limited to this, and the inlet 13 may be located in the center of the short side of the small radius portion 11B. Alternatively, the inlet 13 may be located in the large radius portion 11A.

[0064] (5) In the above embodiment, the reinforcing portion is provided on both sides in the width direction of the extension portion 25 and the bottom portion 43. However, it is not limited to this, and the reinforcing portion may be provided on one side in the width direction of the extension portion 25 and the bottom portion 43, or in the center in the width direction.

[0065] (6) Multiple functions of one component in the above embodiment 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. Furthermore, some of the configurations of the above embodiment may be omitted. Furthermore, at least some of the configurations of the above embodiment may be added to or replaced with the configurations of other above embodiments. [Explanation of Symbols]

[0066] 1...Muffler, 1A...Axis, 10...Shell, 11...Side wall, 11A...Large radius section, 11B...Small radius section, 12...End plate, 13...Inlet, 14...Inlet pipe, 15...Separator, 16...Internal pipe, 2...Stay, 20...First wall section, 21...Hole section, 22...Joint section, 23...Second wall section, 24...Base section, 25...Extension section, 26...Reinforcement section, 30...Upstream pipe, 31...Downstream pipe, 4...Second wall section, 4A...Sound-absorbing chamber, 4B...Sound-absorbing material, 40...Base section, 41...Extension section, 42...Contact section, 43...Bottom section, 43A...Hole, 44...Reinforcement section.

Claims

1. A muffler configured to be mounted on a vehicle, A shell having cylindrical side walls extending along an axis and plates closing both ends of the side walls, An inlet pipe is provided so as to protrude into the interior of the shell from an exhaust gas inlet provided in the side wall, The system includes a stay that supports the inlet pipe, The aforementioned stay is, The first wall portion is a plate-like portion having a hole through which the inlet pipe penetrates and is partially joined to the inner circumferential surface of the side wall, It comprises a second wall portion which is a plate-shaped portion extending from the end of the first wall portion, The direction that is substantially perpendicular to the aforementioned axis and along the inner circumferential surface of the side wall is defined as the circumferential direction. The second wall portion is, A portion joined to the inner circumferential surface of the side wall, provided adjacent to the first wall portion, and having a base portion whose length in the axial direction narrows as it moves toward the opposite side of the first wall portion along the circumferential direction, A portion joined to the inner circumferential surface of the side wall, comprising an extension extending in the circumferential direction from the tip opposite the first wall portion at the base, A reinforcing portion that reinforces the base and the extension, It has, The base and the extension are in contact with the inner circumferential surface of the side wall over substantially their entire area. The reinforcing portion protrudes from both ends of the extension portion in the axial direction and from both ends of the base portion in the axial direction to the side opposite to the inner circumferential surface of the side wall, and is provided along the circumferential direction. scarf.

2. The muffler according to claim 1, The cross-section of the side wall perpendicular to the axis has a shape that extends in the longitudinal direction. In the aforementioned side wall, the portion extending along the longitudinal direction is defined as a large radius portion. The base and the extension are joined to the large radius portion. scarf.

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