JP6069232B2 - Muffler mounting structure for small vehicles - Google Patents

Description

  The present invention relates to a muffler mounting structure for a small vehicle in which a muffler connected downstream of an exhaust pipe is fixed to a vehicle body via a muffler bracket.

  Small vehicles such as motorcycles have a muffler that is connected downstream of the exhaust pipe and connected to the vehicle body via a muffler bracket. This muffler closes the cylindrical muffler body and the front end of the muffler body. A structure having a front cap for closing and an end cap for closing the rear end is known. In this type of vehicle muffler mounting structure, the muffler bracket is divided into left and right parts, and they are overlapped and integrated to extend from the muffler body to the front end of the muffler (front cap) and further to the exhaust pipe A structure that is welded and fixed to the muffler side has been proposed (for example, see Patent Document 1).

JP 2010-276005 A

However, in the conventional configuration, since the welded portion extends in the longitudinal direction (front-rear direction) of the muffler, the welded portion is easily visible from the appearance and may be conspicuous. On the other hand, considering muffler vibration countermeasures, the rigidity of the muffler bracket attached to the muffler is high, so it is difficult to reduce the number of welding locations so as to be inconspicuous.
For this reason, in the conventional configuration, it has been difficult to achieve both securing the appearance between the muffler bracket and the muffler and securing the mounting rigidity.

  The present invention has been made in view of the above-described circumstances, and has a muffler mounting structure for a small vehicle that makes it easy to secure the mounting rigidity of the muffler bracket while making the welding position between the muffler bracket and the muffler inconspicuous from the appearance. The purpose is to provide.

In order to solve the above-described problems, the present invention includes a muffler (29) connected downstream of the exhaust pipe (30) and connected to the vehicle body via a muffler bracket (51), and the muffler (29) However, in the muffler mounting structure for a small vehicle having a cylindrical muffler body (29A) and a cap portion (29B) for closing the front end of the muffler body (29A), the muffler bracket (51) has a left-right divided structure. The bracket half on the inner side of the vehicle body is a mounting bracket (71) that is welded and fixed only to the side surface opposite to the one outer side surface constituting the appearance design surface of the muffler body (29A). Is welded and fixed only to the opposite side surface to the one outer side surface constituting the appearance design surface of the cap part (29B). It is a reinforcing bracket (81) fixed to the mounting bracket (71), and the mounting bracket (71) and the reinforcing bracket (81) are tightening boss portions (91, 92) used for connection to the vehicle body side. while periphery at the side is welded by lamination, the muffler (29) toward the side contrary position or et away in the middle, at the rear of said reinforcing bracket (81), wherein said mounting bracket (71) muffler Clearances (SA, SB) that open up and down are provided between the body (29A), and a joint portion (29A) between the muffler body (29A) and the cap portion (29B) is provided in the clearances (SA, SB). W4) is located.
According to this configuration, the welding location between the mounting bracket and the exhaust muffler and the welding location between the reinforcing bracket and the exhaust muffler are not exposed on the external design surface of the exhaust muffler. Further, the reinforcing effect of the reinforcing bracket makes it easy to improve the mounting rigidity of the muffler bracket and the muffler support rigidity. Therefore, it becomes easy to ensure the mounting rigidity of the muffler bracket while making the welded portion between the muffler bracket and the muffler inconspicuous from the appearance.
Further, the reinforcing bracket can be downsized while ensuring the rigidity of the mounting portion of the muffler bracket on the vehicle body side, and the joint portion between the muffler body and the cap portion does not interfere with the mounting of the reinforcing bracket. Thereby, while avoiding enlargement of a reinforcement bracket etc., the welding range of a junction part can be suppressed, and it becomes easy to avoid the cost increase by the weight increase and the welding range increase.
In addition, the reinforcing bracket can be welded and fixed using an area that is difficult to see from the appearance of the front cap, which is a cap portion that closes the front end of the muffler body, and the welding location can be made inconspicuous from the appearance. .

In the above-described configuration, the length from the mounting position of the reinforcing bracket (81) on the vehicle body side to the welding position with the muffler (29) is from the mounting position of the mounting bracket (71) on the vehicle body side to the muffler (29). It may be configured to be shorter than the length up to the weld location . According to this structure, the rigidity of a reinforcement bracket can be ensured and the reinforcement effect can be heightened.
In the above configuration, the muffler (29) may have a flat shape that is longer in the vertical direction than in the left and right lengths. According to this structure, the opposite side with respect to the external appearance design surface of the exhaust muffler can be secured widely, and the welding position of each bracket can be easily secured.

  Further, in the above-described configuration, the mounting portions (73, 74) on the vehicle body side of the mounting bracket (71) are disposed apart from each other in the vertical direction, and the mounting portions (73, 74) are respectively disposed on the muffler (29) side. The fastening boss portions (91, 92) may be provided integrally, and the attachment portions (73, 74) may be connected to the vehicle body side via the respective fastening boss portions (91, 92). According to this configuration, it is possible to secure a large number of locations where the muffler bracket is welded to the vehicle body, and it is possible to simplify the structure of the mounting bracket and avoid an increase in size by using the tightening boss portion.

  Further, in the above-described configuration, a plurality of independent reinforcing brackets (82, 83) are provided so as to individually include the tightening boss portions (91, 92), and each of the reinforcing brackets (82, 83) includes the mounting bracket (82, 83). 71) may be welded and fixed. According to this configuration, each reinforcing bracket can be easily miniaturized while ensuring an appropriate reinforcing effect, so that the expansion of the projected area of the reinforcing bracket from the appearance design surface of the muffler can be suppressed and the appearance can be improved.

  Further, in the above configuration, the reinforcing bracket (83) closer to the exhaust pipe (30) among the plurality of the reinforcing brackets (82, 83) includes the exhaust pipe so as to surround a part of the exhaust pipe (30) from above and below. You may make it weld-fix to the said cap part (29B) in an up-down position with respect to a pipe | tube (30). According to this configuration, the support including the exhaust pipe can be supported by the reinforcing bracket near the exhaust pipe, and the number of support portions dedicated to the exhaust pipe can be reduced.

  Further, in the above-described configuration, the reinforcing bracket (82) separated from the exhaust pipe (30) among the plurality of the reinforcing brackets (82, 83) is welded to the cap portion (29B) with a space in the vertical direction. A first welding location (W2B, W2C) to be fixed and a second welding location (W2B, W2C) to be fixed to the cap portion (29B) by extending vertically between the upper and lower first welding locations (W2B, W2C) ( W2A) may be fixed to the cap portion (29B). According to this configuration, it is possible to increase the number of welding locations by utilizing the fact that the welding locations are not affected by the exhaust pipe, and it is easy to increase the attachment rigidity of the muffler bracket.

  In the present invention, the muffler bracket is a mounting bracket that is welded and fixed only to the side surface opposite to one outer surface that constitutes the appearance design surface of the muffler body, and one that constitutes the appearance design surface of the cap portion that closes one end of the muffler body. Since it is welded and fixed only on the opposite side to the outer side and is provided with a reinforcing bracket that is fixed to the mounting bracket, the mounting location of the muffler bracket, etc., while making the welding location of the muffler bracket and muffler inconspicuous It becomes easy to secure.

In addition, if the length from the mounting position of the reinforcing bracket on the vehicle body side to the welded portion with the muffler is configured to be shorter than that of the mounting bracket, the reinforcing bracket can be secured with sufficient rigidity. The effect can be enhanced.
Further, if the muffler has a flat shape that is longer in the vertical direction than the left and right lengths, it is possible to secure a wide side opposite to the external design surface of the exhaust muffler and to easily secure the welding position of each bracket.

  In addition, a mounting portion on the vehicle body side of the mounting bracket is disposed apart vertically, and a fastening boss portion is integrally provided on the muffler side of the mounting portion, and the mounting boss portion is provided via each fastening boss portion. If the portion is connected to the vehicle body side, a large number of locations where the muffler bracket is welded to the vehicle body can be secured, and the structure of the mounting bracket can be simplified.

  Further, if the plurality of independent reinforcing brackets are provided so as to individually include the tightening boss portions, and each reinforcing bracket is welded and fixed to the mounting bracket, each reinforcing bracket can be easily downsized, and the muffler It is possible to suppress the expansion of the projected area of the reinforcing bracket from the external design surface and to improve the appearance.

  Further, the reinforcing bracket near the exhaust pipe is reinforced near the exhaust pipe if it is welded and fixed to the cap portion at a vertical position with respect to the exhaust pipe so as to surround a part of the exhaust pipe from above and below. The bracket enables support including the exhaust pipe, and the number of support points dedicated to the exhaust pipe can be reduced.

  The reinforcing brackets that are separated from the exhaust pipe among the plurality of reinforcing brackets include upper and lower first welding locations that are welded and fixed at an interval in the vertical direction with respect to the cap portion, and upper and lower first welding locations. If the welded part is fixed to the cap part by the second welded part extending vertically between the two parts and welded to the cap part, the welded part is not affected by the exhaust pipe. Increase the mounting rigidity of the muffler bracket.

  Further, the mounting bracket and the reinforcing bracket are welded to each other on the side of the fastening boss used for connection to the vehicle body side by bonding, while the brackets are separated from the midway toward the muffler side. If a gap is provided between them, and the joint between the muffler body and the cap is positioned in the gap, an increase in the size of the reinforcing bracket and the like can be avoided, and the welding range of the joint can be suppressed. It becomes easy to avoid an increase in cost due to an increase in weight or welding range.

  In addition, if the cap portion is a front cap that closes the front end of the muffler body, the reinforcing bracket can be welded and fixed using an area that is difficult to see from the appearance of the front cap, and the welding location can be more The position can be inconspicuous.

1 is a right side view of a motorcycle according to an embodiment of the present invention. It is a right view of an exhaust muffler. It is a longitudinal cross-sectional view which shows the internal structure of an exhaust muffler. It is IV-IV sectional drawing of FIG. It is the figure which looked at the catalytic converter and the downstream exhaust pipe from the rear. It is the figure which looked at the exhaust muffler from the vehicle body inner side (left side). It is the figure which looked at the exhaust muffler from the vehicle body upper direction. It is the figure which looked at the exhaust muffler from the front. It is the figure which looked at the exhaust muffler from the lower part.

  Hereinafter, a motorcycle according to an embodiment of the present invention will be described with reference to the drawings. In the description, descriptions of directions such as front and rear, right and left and up and down are the same as directions with respect to the vehicle body unless otherwise specified. Further, in each figure, the symbol FR indicates the front of the vehicle body, the symbol UP indicates the upper side of the vehicle body, and the symbol LE indicates the left side of the vehicle body.

FIG. 1 is a right side view of the motorcycle 1.
As shown in FIG. 1, the motorcycle 1 is a saddle type scooter type small vehicle in which an occupant sits so as to straddle a seat 10 (occupant seat). A body frame F of the motorcycle 1 includes a front fork 11 that pivotally supports a front wheel WF, a head pipe 13 that supports a steering handle 12 connected to the front fork 11 so as to be steerable, and a rear pipe from the head pipe 13. Down tube 14 that extends downward, cross member 15 that extends in the vehicle width direction and is fixed to the rear end of down tube 14, and a pair of left and right rear members that have the front end fixed to the left and right sides of cross member 15 and extend rearward And a frame pipe 16.

  A bracket 17 is provided at the front end of both rear frame pipes 16 in the vehicle body frame F. A front portion of the power unit P is supported on the bracket 17 through a link mechanism 18 so as to be swingable up and down. A rear wheel WR disposed on the right side of the rear portion of the power unit P is pivotally supported on the rear portion of the power unit P. Is done.

The vehicle body frame F is covered with a synthetic resin vehicle body cover 19 that forms the vehicle body in cooperation with the vehicle body frame F. The vehicle body cover 19 includes a front cover 20 that covers the head pipe 13 from the front, a leg shield 21 that is continuous with the front cover 20 so as to cover the front of the driver's feet, and a step that extends rearward from the lower portion of the leg shield 21. A pair of left and right side covers 23 that are connected to the floor 22 and cover the left and right sides of the vehicle body are provided.
On the side cover 23, there is provided a seat 10 that extends in the front-rear direction and that can seat two people. The footrest portion of the occupant (driver) seated on the front portion of the seat 10 is the step floor 22, and the footrest portion of the occupant (passenger) seated on the rear portion is the side cover behind the step floor 22. 23 is a step bar 27 provided on the left and right of 23.

The power unit P includes an internal combustion engine E and a transmission (not shown) provided between the internal combustion engine E and the rear wheel WR. The upstream end of the exhaust pipe 30 is connected to the cylinder head 26 of the engine body 25 in the internal combustion engine E. Connected.
The exhaust pipe 30 extends downward from the cylinder head 26 and then bends to the side (right side) of the vehicle body to extend the side (right side) of the power unit P to the rear. The exhaust pipe 30 is located behind the internal combustion engine E and on the rear wheel WR side. It is connected to an exhaust muffler (also called a silencer) 29 provided below the side cover 23.

FIG. 2 is a right side view of the exhaust muffler 29, and FIG. 3 is a longitudinal sectional view showing the internal structure of the exhaust muffler 29.
The exhaust muffler 29 is an exhaust system component that lowers the pressure of the exhaust gas discharged from the exhaust pipe 30 and discharges it to the outside from the discharge pipe 31. As shown in FIG. 2, the exhaust muffler 29 has a cylindrical muffler body 29A that opens back and forth, a front cap 29B (cap portion) that closes the front end of the muffler body 29A, and a rear end of the muffler body 29A. The end cap 29C is provided, and these components 29A to 29C are welded and fixed.
The front cap 29B is formed in a curved shape that curves forward convexly, and the end cap 29C is formed in a curved shape that curves backward convexly. By adopting a curved shape, the strength of each cap 29B, 29C can be improved, the air resistance can be reduced, and the appearance can be improved.

As shown in FIGS. 2 and 3, an exhaust pipe insertion port 36 that opens forward is provided at the front lower portion of the front cap 29 </ b> B, and the exhaust pipe 30 is inserted into the exhaust pipe insertion port 36.
The muffler body 29A is formed in a flat shape that is longer in the vertical direction than the left and right lengths. A protector 32 (FIG. 1) is attached to the muffler body 29A so as to cover the outer surface of the lower portion of the muffler body 29A in the vehicle width direction. A protector 34 that covers the outer surface of the upstream exhaust pipe 33 on the outer side in the vehicle width direction is provided on the upstream exhaust pipe 33 (first exhaust pipe) exposed between the power unit P of the exhaust pipe 30 and the exhaust muffler 29. It is attached.

As shown in FIG. 3, the exhaust pipe 30 includes an upstream side exhaust pipe 33 between the power unit P and the exhaust muffler 29 and a downstream side exhaust pipe 35 accommodated in the exhaust muffler 29. The upstream exhaust pipe 33 is connected to the cylinder head 26 of the internal combustion engine E at the upstream end, extends from the cylinder head 26 to the right side of the rear wheel WR, and expands toward the downstream side. 37 is connected.
The expanded pipe 37 is formed as a stepped pipe for connecting the upstream exhaust pipe 33 and the catalytic converter 41 having different diameters, and the upstream end (small diameter side) is inserted into the exhaust pipe insertion port 36 from the inside of the exhaust muffler 29. Then, it is exposed outside the exhaust muffler 29 (in front of the front cap 29B). Thereby, the upstream side exhaust pipe 33 can be easily connected from the outside of the exhaust muffler 29. Further, the downstream end (large diameter side) of the diameter expansion pipe 37 opens rearward at the front lower portion in the exhaust muffler 29, and the upstream end of the catalytic converter 41 is welded and fixed.

The catalytic converter 41 includes a catalyst carrier 42 that supports a catalyst that purifies exhaust gas by an oxidation / reduction reaction, and a cylindrical cylinder 43 that houses the catalyst carrier 42. By connecting the upstream end of the cylindrical body 43 to the enlarged diameter pipe 37, the catalytic converter 41 is supported by the front lower portion in the exhaust muffler 29.
The cylindrical body 43 of the catalytic converter 41 extends rearward along the bottom surface M1 of the exhaust muffler 29, and a diameter-reduced tube 44 that is reduced in diameter toward the downstream side is connected to the rear end thereof. The diameter-reduced tube 44 passes through a partition plate (also referred to as a separator) 45 that partitions the exhaust muffler 29 forward and backward, and is supported by the partition plate 45.

FIG. 4 shows a cross-sectional structure of the exhaust muffler 29 (corresponding to the IV-IV cross section of FIG. 3). The exhaust muffler 29 is formed in a flat shape that is longer in the vertical direction than the left and right lengths, and the partition plate 45 extends in the exhaust muffler 29 in the horizontal and vertical directions. The partition plate 45 is provided with a plurality of (three in the present configuration) openings 45A, 45B, and 45C spaced vertically, and the reduced diameter tube 44 is inserted into the lowermost opening 45A. It is fixed by welding. A downstream exhaust pipe 35 connected to the downstream end of the reduced diameter pipe 44 is inserted into the uppermost opening 45C and welded and fixed, and a communication pipe 47 described later is provided in the upper and lower central opening 45B. It is inserted and fixed by welding.
As shown in FIG. 4, the exhaust muffler 29 is formed in a double structure having an outer case 29M and an inner case 29N. The inner case 29N is formed of a punching metal having a large number of pores 29H, and a sound absorbing material 29P such as glass wool is filled between the cases 29M and 29N, so that the sound in the exhaust muffler 29 is hardly leaked to the outside. Has been.

  In this configuration, as shown in FIG. 3, the catalytic converter 41 is disposed in the front chamber R <b> 1 partitioned by the partition plate 45, so that the center of gravity of the exhaust muffler 29 is at the front position. For this reason, it can be brought close to the power unit P having the most weight among the body parts, which is advantageous for mass concentration. Further, since the catalytic converter 41 is not accommodated, the capacity of the rear chamber R2 having the exhaust pipe insertion port 36 can be increased. Therefore, it is advantageous for securing the arrangement space of the downstream side exhaust pipe 35 and reducing the pressure of the exhaust gas.

  The downstream exhaust pipe 35 extends rearward from the catalytic converter 41 side (reduced diameter pipe 44), then bends and extends forward, penetrates the partition plate 45, and its downstream end 35E is partitioned by the partition plate 45. Open in the front chamber R1. The downstream side exhaust pipe 35 is divided into two parts, the upstream side and the downstream side, and the upstream side pipe 35A (hereinafter referred to as the second exhaust pipe) is rearward from the catalytic converter 41 side (the reduced diameter pipe 44). It is formed into a bent tube that extends forward and then bends forward. On the other hand, the downstream pipe 35B (hereinafter referred to as the third exhaust pipe) is a J-shaped J-shaped pipe as viewed from the side, which extends straight forward from the second exhaust pipe 35A and then bends downward in the front chamber. Formed.

In addition to the partition plate 45, the third exhaust pipe 35 </ b> B penetrates a tube support plate 46 disposed at a distance in front of the partition plate 45, and is welded and fixed to the partition plate 45 and the tube support plate 46. Is supported by More specifically, the straight portion of the third exhaust pipe 35 </ b> B is supported through the partition plate 45 and the pipe support plate 46. For this reason, the attachment work of the 3rd exhaust pipe 35B is easy.
Further, the pipe support plate 46 extends below the third exhaust pipe 35B, and supports a communication pipe 47 that communicates the front chamber R1 and the rear chamber R2 of the partition plate 45 below the third exhaust pipe 35B. Note that the lower end of the tube support plate 46 extends to a position above the catalytic converter 41. That is, the tube support plate 46 does not completely partition the front chamber R1.

With the above configuration, the downstream exhaust pipe 35 extends annularly in the exhaust muffler 29 along the bottom surface M1, the back surface M2, the top surface M3, and the front surface M4 of the exhaust muffler 29, and the downstream end 35E is connected to the catalytic converter 41. It is arranged on the front upper side. Thus, the exhaust pipe 30 can be made as long as possible, the exhaust pressure can be reduced, and the exhaust gas discharged from the exhaust pipe 30 can flow toward the catalytic converter 41. In FIG. 3, the symbol G indicates the directivity direction of the exhaust gas outlet 44A.
Therefore, the temperature of the catalytic converter 41 can be accelerated by the relatively high temperature exhaust gas after passing through the catalytic converter 41, and the catalyst can be activated early. In addition, the temperature of the catalytic converter 41 can be accelerated by heat generated from the downstream exhaust pipe 35 and the communication pipe 47 disposed in the exhaust muffler 29. Therefore, the catalyst can be activated more rapidly by these synergistic effects.

  The exhaust gas of the internal combustion engine E is discharged from the downstream end 35E of the exhaust pipe 30 to the front chamber R1, and then discharged to the rear chamber R2 through the communication pipe 47 having one end opened in the front chamber R1. And discharged from the discharge pipe 31 to the outside. As a result, the front chamber R1 functions as a first expansion chamber that reduces the pressure of the exhaust gas, and the rear chamber R2 functions as a second expansion chamber that further reduces the pressure of the exhaust gas, thereby reducing the exhaust pressure. Can be reduced.

FIG. 5 is a view of the catalytic converter 41 and the downstream exhaust pipe 35 as viewed from the rear.
As shown in FIG. 5, the catalytic converter 41 is disposed close to the vehicle width direction outer side (opposite the rear wheel WR) in the lower part of the exhaust muffler 29, and a gap S <b> 1 is formed between the exhaust muffler 29 and the catalytic converter 41. Form.
The second exhaust pipe 35A constituting the upstream portion of the downstream exhaust pipe 35 approaches the inner side in the vehicle width direction (rear wheel WR side) as it goes downstream from the catalytic converter 41 side (reduced diameter pipe 44), and the downstream side exhaust The third exhaust pipe 35B constituting the downstream portion of the pipe 35 is arranged on the inner side in the vehicle width direction (the rear wheel WR side) than the catalytic converter 41. Further, the directivity direction G of the downstream end 35E of the downstream side exhaust pipe 35 is an oblique direction toward the outside in the vehicle width direction as it goes downward. As a result, the exhaust gas discharged from the downstream end 35E can flow toward the catalytic converter 41 and can be smoothly introduced into the communication pipe 47 through the gap S1 vacant on the inner side in the vehicle width direction of the catalytic converter 41. .

Next, the muffler mounting structure will be described.
6 is a view of the exhaust muffler 29 as seen from the inside of the vehicle body (corresponding to the left side view), and FIG. 7 is a view of the exhaust muffler 29 as seen from above the vehicle body. FIG. 8 is a view of the exhaust muffler 29 as viewed from the front, and FIG. 9 is a view of the exhaust muffler 29 as viewed from below.
As shown in FIG. 6, a muffler bracket 51 is attached to the exhaust muffler 29, and the exhaust muffler 29 is attached to the vehicle body side (power unit P in this configuration) via the muffler bracket 51. The muffler bracket 51 has a pair of upper and lower arms 52 and 53 that extend forward from the exhaust muffler 29 as viewed from the side of the vehicle body (right side of the vehicle body) (see FIGS. 1 and 2). The front ends of the pair of upper and lower arms 52 and 53 are fastened to the rear end of the power unit P by fastening bolts 61 and 62 (fastening members) shown in FIG. For this reason, the bolt fastening portion (the front ends of the arm portions 52 and 53) is exposed to the outside, and the exhaust muffler 29 can be easily attached and detached from the outside (right side) of the vehicle body.

Since the exhaust muffler 29 is viewed from the right side of the vehicle body, the right side surface 29R (FIG. 2) constitutes the exterior design surface. On the other hand, the left side surface 29L (FIG. 6) facing the vehicle body inner side (vehicle width direction inner side) is hardly visible from the vehicle body left side. This is because, as shown in FIG. 1, the rear wheel WR, which is a vehicle body component, is located inside (left side) the left side surface 29L of the exhaust muffler 29. In particular, the front area (front side of the vehicle body inner side) of the left side surface 29L of the exhaust muffler 29 has a rear wheel WR located in the front, rear, and upper and lower sides of the exhaust muffler 29. It is difficult to see from.
In this embodiment, as shown in FIGS. 6 and 7, the muffler bracket 51 is a bracket structure that is welded and fixed to the front region of the left side surface 29 </ b> L of the exhaust muffler 29, and the right side surface 29 </ b> R that constitutes the vehicle exterior surface is provided on the right side surface 29 </ b> R. The muffler bracket 51 is configured so that there is no welded portion.

More specifically, the muffler bracket 51 is formed in a left and right divided structure, and as shown in FIG. 8, the bracket half on the inner side (left side) of the vehicle body is welded and fixed to the front region of the left side surface 29 </ b> L of the exhaust muffler 29. The relatively large mounting bracket 71 is formed. A bracket half on the outside of the vehicle body is formed on a relatively small reinforcing bracket 81 that is welded and fixed so as to bridge between the front region of the left side surface 29L of the exhaust muffler 29 and the mounting bracket 71.
As shown in FIG. 6, the mounting bracket 71 includes a plate-shaped welding fixing portion 72 (a mounting portion on the muffler 29 side) that is welded and fixed to the front region of the left side surface 29 </ b> L of the muffler body 29 </ b> A, and the welding fixing portion 72. A pair of upper and lower plate-like extensions 73 and 74 (vehicle body side mounting portions) that extend obliquely toward the inside of the vehicle body and forward are integrally provided. For example, the mounting bracket 71 is manufactured by bending a metal plate member.

The welding fixing portion 72 is formed in a vertically long plate shape extending vertically within the vertical width of the muffler body 29A, and its upper edge, rear edge and lower edge are welded and fixed to the muffler body 29A. Here, in FIG. 6 to FIG. 9, the welding locations of the upper edge, the rear edge, and the lower edge are shown with reference characters W1A, W1B, and W1C.
For this reason, as shown in FIG. 2, the welding fixing part 72 and the welding locations W1A to W1C are not viewed from the outside of the vehicle body (right side of the vehicle body) and are not conspicuous from the appearance. As shown in FIG. 6 and FIG. 9, the welding locations include upper and lower welding locations W1A and W1C (first welding locations) and welding locations W1B (second welding locations) extending vertically between the welding locations. The length can be sufficiently secured, and the joining strength of the mounting bracket 71 can be sufficiently secured.

As shown in FIG. 8, the pair of upper and lower extensions 73 and 74 are formed in a concave cross section recessed inward of the vehicle body, and the muffler body 29A has a space between the muffler body 29A and the muffler body 29A. Extend forward. These extension parts 73 and 74 constitute a part of the pair of upper and lower arm parts 52 and 53 described above.
Further, as shown in FIG. 6, each of the pair of upper and lower extensions 73 and 74 has through holes 61 </ b> A and 62 </ b> A through which the fastening bolts 61 (FIG. 1) pass at the front ends, and reduces the weight of the mounting bracket 71. For opening 76.
On the other hand, the upper extension 73 is inclined and extended inward of the vehicle body so as to be located on the vehicle inner side with respect to the lower extension 74, and the front end thereof is on the vehicle inner side (right side) with respect to the lower extension 74. It is provided at a position offset upward and forward (see FIGS. 6 to 9).

As shown in FIGS. 7 and 9, the through holes 61A and 62A provided at the front ends are parallel to each other, are formed in holes along the vehicle width direction, and are tightening bosses through which the fastening bolts 61 and 62 are inserted. The portions 91 and 92 are welded and fixed on the same axis. Therefore, the muffler bracket 51 is fixed to the vehicle body by inserting the fastening bolts 61 and 62 (fastening members) into the fastening boss portions 91 and 92 from the outside of the vehicle body and fastening the fastening bolts 61 and 62 to the vehicle body side. Can do.
In this case, since the location where the muffler bracket 51 is fixed to the vehicle body is separated from front to back, right and left and up and down, the mounting strength of the muffler bracket 51 is increased and the support strength of the exhaust muffler 29 is easily increased. In addition, since the pair of upper and lower extension parts 73 and 74 are formed in the concave cross section, the rigidity of the arm parts 52 and 53 can be efficiently increased as compared with the case of forming a simple flat plate shape. This also facilitates enhancing the support strength of the exhaust muffler 29.

  As shown in FIG. 8, the reinforcing bracket 81 is a bracket that is welded and fixed to the left side surface 29L of the front cap 29B, and a pair of upper and lower reinforcing brackets 82 that reinforce each of the upper and lower extension portions 73 and 74 independently. , 83. The reinforcing brackets 82 and 83 constitute the remaining portions of the pair of upper and lower arms 52 and 53 described above. These reinforcing brackets 82 and 83 are manufactured, for example, by bending a metal plate member.

  The upper reinforcing bracket 82 includes a front plate 84 that extends obliquely from the left side surface 29L of the front cap 29B toward the vehicle body inside and forward, and an upper plate 85 that extends from the upper edge of the front plate 84 to the vehicle body inner side (left side) and the vehicle body rear. And a lower plate 86 extending from the lower edge of the front plate 84 toward the vehicle body inner side (left side) and the vehicle body rear side. The front plate 84, the upper plate 85, and the lower plate 86 are provided with extension portions 84A, 85A, and 86A that extend along the left side surface 29L of the front cap 29B, and these extension portions 84A to 86A are connected to the front cap 29B. The left side surface 29L is welded and fixed while being in surface contact.

Here, in FIG. 6 to FIG. 9, the welding locations of the front plate 84, the upper plate 85, and the lower plate 86 are shown with reference numerals W2A, W2B, and W2C.
With this configuration, the front plate 84, the upper plate 85, and the lower plate 86 including the extension portions 84A to 86A are not viewed from the outside of the vehicle body (right side of the vehicle body) as shown in FIG. In addition, the welded portions W2A to W2C are not viewed from the outside of the vehicle body.
Further, as shown in FIG. 8, since the upper and lower welding locations W2B, W2C (first welding location) and the welding location W2A (second welding location) extending vertically between these are provided, a sufficient welding length is ensured. Therefore, the joining strength of the reinforcing bracket 82 can be sufficiently increased.

Furthermore, since the upper reinforcing bracket 82 is formed by the front plate 84, the upper plate 85, and the lower plate 86 in a concave cross section that is recessed to the outside of the vehicle body, the reinforcing bracket 82 is compared with a case where it is formed in a simple flat plate shape. The rigidity of itself can be increased efficiently. Accordingly, the reinforcing effect can be increased.
Further, a fastening boss 91 is fixedly attached between the tip end portion (muffler side attachment portion) of the reinforcing bracket 82 having a concave cross section and the upper extension portion 73 of the attachment bracket 71. The peripheral edges (upper plate 85 and lower plate 86) are welded together by sandwiching the boss portion 91 therebetween. A plurality of the upper and lower welding locations W3A, W3C (FIGS. 8 and 9) are provided in the front-rear direction and at intervals in the front-rear direction.
In this way, the bonding strength between the reinforcing bracket 82 and the mounting bracket 71 can be increased. In addition, since the attachment portion of the muffler bracket 51 to the vehicle body side can be formed in a cylindrical cross section, the rigidity of the muffler bracket 51, particularly the rigidity around the fastening boss portion 91 can be efficiently increased.

Further, the upper reinforcing bracket 82 is welded to the exhaust muffler 29 away from the mounting bracket 71 as it goes to the exhaust muffler 29, and in front of the welding locations W1A to W1C of the mounting bracket 71. For this reason, the length from the attachment position on the vehicle body side of the upper reinforcing bracket 82 to the welding location with the exhaust muffler 29 is the length from the attachment position on the vehicle mounting side of the attachment bracket 71 to the welding location with the exhaust muffler 29. It is shorter than that.
Since the exhaust muffler 29 and the mounting bracket 71 are bridged by the relatively short reinforcing bracket 82 as described above, the relatively long mounting bracket 71 can be efficiently reinforced.

As shown in FIGS. 7 and 8, the upper reinforcing bracket 82 is separated from the mounting bracket 71 as it goes to the exhaust muffler 29, so that the rear of the reinforcing bracket 82 is between the mounting bracket 71 and the exhaust muffler 29. A gap SA that opens up and down is formed.
A joint W4 (see FIG. 9) between the muffler body 29A and the front cap 29B is located in the gap SA. For this reason, it is possible to prevent the joint portion W4 from interfering with the mounting of the brackets 71 and 82 while ensuring the rigidity of the mounting portion of the muffler bracket 51 on the vehicle body side. Thereby, while enlarging the reinforcement bracket 82 etc., the welding range of the junction part W4 can be suppressed.

  Further, the clearance SA and the above-described opening 76 can easily release the heat of the left side surface 29L of the exhaust muffler 29 upward, and can easily cool the left side surface 29L with the traveling wind from the front. .

  The lower reinforcing bracket 83 has substantially the same structure as the upper reinforcing bracket 82. That is, the lower reinforcing bracket 83 extends from the left side surface 29L of the front cap 29B obliquely toward the vehicle body inner side and the front side, and extends from the upper edge of the front plate 87 to the vehicle body inner side (left side) and the vehicle body rear side. An upper plate 88 and a lower plate 89 extending from the lower edge of the front plate 87 to the vehicle body inner side (left side) and the vehicle body rear side are provided. The front plate 87, the upper plate 88, and the lower plate 89 are provided with extension portions 87A, 88A, and 89A extending along the left side surface 29L of the front cap 29B, and these extension portions 88A and 89A are provided with the front cap 29B. Is fixed to the left side surface 29L by welding.

Here, in FIG. 6 to FIG. 9, the welding locations of the upper and lower extensions 88 </ b> A and 89 </ b> A are shown with reference numerals W <b> 5 </ b> A and W <b> 5 </ b> B.
In this configuration, as shown in FIG. 8, the extension portions 87A to 89A of the front plate 87, the upper plate 88, and the lower plate 89 extend along the periphery of the upstream side exhaust pipe 33 (first exhaust pipe), It is formed so as to surround the upper and lower sides of the upstream side exhaust pipe 33 and the inside of the vehicle body. In this way, the exhaust pipe 30 is enclosed from above and below and joined to the front cap 29B at the welding positions W5A and W5B at the top and bottom positions, so that the reinforcing bracket 83 can be joined close to the upstream exhaust pipe 33 and the upstream exhaust pipe 33 can be joined. Including support is possible. As a result, it is possible to reduce the number of support portions dedicated to the upstream side exhaust pipe 33.

More specifically, in this configuration, the extension portions 87A and 89A below the upstream side exhaust pipe 33 project outside the vehicle body (on the right side) from the extension portion 88A above the exhaust pipe 30 and the lower edge thereof extends to the front cap 29B. It is welded and fixed (corresponding to welding location W5B).
In this case, since the welding location W5B is located below the upstream side exhaust pipe 33, it is difficult to visually recognize the welding location W5B from above.
In addition, since the extension 88A above the upstream side exhaust pipe 33 is welded and fixed at a position deeper inside the vehicle body than the exhaust pipe 30, it is difficult to visually recognize the welded portion W5A (FIG. 8) from the appearance. . Therefore, the welding locations W5A and W5B between the reinforcing bracket 83 and the front cap 29B can be made inconspicuous effectively.

Similarly to the upper reinforcing bracket 82, the lower reinforcing bracket 83 is formed by the front plate 87, the upper plate 88, and the lower plate 89 into a concave cross section that is recessed toward the outside of the vehicle body. Can be improved efficiently.
Further, a fastening boss 92 is attached and fixed between the tip end portion (muffler side attachment portion) of the reinforcing bracket 83 and the lower extension portion 74 of the attachment bracket 71, and tightening is performed. The peripheral edges (upper plate 88 and lower plate 89) are welded together by sandwiching the attached boss portion 92 therebetween. The pair of upper and lower welding locations W6A and W6C (FIGS. 8 and 9) extend in the front-rear direction and are provided in a plurality with a space in the front-rear direction.
In this way, the joint strength between the reinforcing bracket 83 and the mounting bracket 71 can be increased, and the mounting portion of the muffler bracket 51 on the vehicle body side can be formed in a cylindrical cross section. It is possible to efficiently increase the rigidity around the portion 92.

  Further, the lower reinforcing bracket 83 is separated from the mounting bracket 71 as it goes to the exhaust muffler 29 side, similarly to the upper reinforcing bracket 82, and in front of the welding locations W1A to W1C of the mounting bracket 71, the exhaust muffler 29. To be welded. For this reason, the length from the mounting position of the lower reinforcing bracket 83 on the vehicle body side to the welding location with the exhaust muffler 29 is the length from the mounting position of the mounting bracket 71 to the exhaust muffler 29 to the welding location with the exhaust muffler 29. Therefore, the relatively long mounting bracket 71 can be efficiently reinforced.

  Further, a clearance SB (FIGS. 8 and 9) that opens up and down is formed between the mounting bracket 71 and the exhaust muffler 29 behind the reinforcing bracket 83. A joint W4 (see FIG. 9) between the muffler body 29A and the front cap 29B is located in the gap SB. For this reason, it is possible to prevent the joint W4 from interfering with the mounting of the brackets 71 and 83 while ensuring the rigidity of the mounting portion of the muffler bracket 51 on the vehicle body side. Thereby, while enlarging the reinforcement bracket 83 etc., the welding range of the junction part W4 can be suppressed.

As described above, the muffler bracket 51 of the present embodiment is the mounting bracket 71 that is welded and fixed only to the opposite side surface (left side surface 29L) with respect to one outer side surface (right side surface 29R) constituting the appearance design surface of the muffler body 29A. And a reinforcing bracket 81 that is welded and fixed only to the opposite side surface (left side surface 29L) with respect to one outer side surface (right side surface 29R) constituting the appearance design surface of the front cap 29B (cap portion). And.
According to this configuration, the welded locations W1A to W1C between the mounting bracket 71 and the exhaust muffler 29 and the welded locations W2A to W2C, W5A, and W5B between the reinforcing bracket 81 and the exhaust muffler 29 are the appearance design surface of the exhaust muffler 29. The rigidity of the muffler bracket 51 itself, the rigidity of attachment to the exhaust muffler 29, the muffler support rigidity, and the like are easily improved by the reinforcing effect of the reinforcing bracket 81.
Therefore, it becomes easy to ensure various rigidity desired for the muffler bracket 51 while making the welding location of the muffler bracket 51 and the exhaust muffler 29 inconspicuous from the appearance.

Moreover, since the mounting bracket 71 is welded and fixed to the muffler body 29A, and the reinforcing bracket 81 is welded and fixed to the front cap 29B, the mounting bracket 71 and the reinforcing bracket 81 are welded and fixed to the same component (for example, the muffler body 29A). Compared to the case, it is easy to secure a welding region and the degree of freedom in design is improved.
In addition, since the rear wheel WR, the power unit P, the vehicle body frame F, and the like are present on the inner side (in the vehicle width direction), the side surface (left side surface 29L) opposite to the exterior design surface of the front cap 29B is particularly visually recognized from the exterior. It becomes a difficult area. In this configuration, the reinforcing bracket 81 is welded and fixed using an area that is difficult to visually recognize from the external appearance of the front cap 29B, so that the welding location can be made inconspicuous from the external appearance.
The mounting bracket 71 is also welded and fixed to the front region of the muffler body 29A opposite to the exterior design surface (left side surface 29L). Can be placed in a more inconspicuous position.

Further, since the length from the mounting position of the reinforcing bracket 81 on the vehicle body side to the welding position with the exhaust muffler 29 is shorter than that of the mounting bracket 71, the rigidity of the reinforcing bracket 81 is secured and the reinforcing effect is achieved. Can be increased.
Further, since the exhaust muffler 29 of this configuration is formed in a flat shape that is longer in the vertical direction than the left and right lengths, it is possible to ensure a wide side surface (left side surface 29L) opposite to the exterior design surface of the exhaust muffler 29. . Therefore, it becomes easy to ensure the welding position of each bracket 81,71.

Further, as shown in FIGS. 6 and 8, extension parts 73 and 74 that are attachment parts on the vehicle body side of the attachment bracket 71 are arranged apart from each other in the vertical direction, and the exhaust muffler 29 is provided in each of the extension parts 73 and 74. The fastening boss portions 91 and 92 are integrally provided on the side, and the extension portions 73 and 74 are connected to the vehicle body side via the fastening boss portions 91 and 92. According to this configuration, it is possible to secure a large number of locations where the muffler bracket 51 is welded to the vehicle body, and it is possible to simplify the structure of the mounting bracket 71 and avoid an increase in size by using the fastening boss portions 91 and 92.
In addition, a plurality of independent reinforcing brackets 82 and 83 are provided so as to individually include the tightening boss portions 91 and 92, and the reinforcing brackets 82 and 83 are welded and fixed to the mounting bracket 71. Compared to the case, the reinforcing brackets 82 and 83 can be easily downsized while ensuring an appropriate reinforcing effect. Thereby, the expansion of the projection area of the reinforcement brackets 82 and 83 from the appearance design surface of the exhaust muffler 29 can be suppressed, and the appearance can be improved.

Further, among the plurality of reinforcing brackets 82 and 83, the reinforcing bracket 83 closer to the exhaust pipe 30 is located at a vertical position with respect to the exhaust pipe 30 so as to surround a part of the exhaust pipe 30 from above and below as shown in FIG. It is welded and fixed to the front cap 29B. Thereby, the support including the exhaust pipe 30 can be performed by the reinforcing bracket 83 near the exhaust pipe 30. Accordingly, it is possible to reduce the number of support portions dedicated to the exhaust pipe 30.
Further, the reinforcing bracket 82 separated from the exhaust pipe 30 includes upper and lower welding locations W2B and W2C (first welding locations) that are welded and fixed to the front cap 29B with a vertical interval, and upper and lower welding locations W2B and It is fixed to the front cap 29B by a welding location W2A (second welding location) that extends vertically between W2C and is welded and fixed to the front cap 29B. This makes it possible to increase the number of welding locations by utilizing the fact that the welding locations are not affected by the exhaust pipe 30, and it is easy to increase the attachment rigidity and the muffler support rigidity of the muffler bracket 51.

In addition, the mounting bracket 71 and the reinforcing brackets 82 and 83 are welded to each other on the fastening boss portions 91 and 92 used for connection to the vehicle body side by bonding, and at the midpoint toward the exhaust muffler 29 side. Clearances SA, SB are provided between the mounting bracket 71 and the mounting bracket 71, and a joint W4 (FIG. 9) between the muffler body 29A and the front cap 29B (cap part) is positioned in the clearances SA, SB. .
Thereby, it is possible to reduce the size of the reinforcing brackets 82 and 83 while ensuring the rigidity of the mounting portion of the muffler bracket 51 on the vehicle body side, and the joint portion W4 does not interfere with the mounting of the brackets 71 and 82. Accordingly, it is possible to avoid an increase in the size of the reinforcing brackets 82 and 83 and to suppress the welding range of the joint portion W4, and to easily avoid an increase in cost due to an increase in weight and an increase in the welding range.

The above-described embodiment is merely an aspect of the present invention, and can be arbitrarily changed without departing from the gist of the present invention.
For example, in the above-described embodiment, the case where the reinforcing bracket 81 is welded and fixed to the front cap 29B has been described, but the present invention is not limited thereto. For example, the end cap 29C (cap portion) may be welded and fixed to the opposite side surface of the outer design surface constituting the outer appearance design surface, or the muffler body 29A may be welded and fixed to the opposite side surface of the outer design surface constituting the outer appearance design surface. You may do it.
In the above-described embodiment, the case where the exhaust muffler 29 has a flat shape that is long in the vertical direction has been described. However, the present invention is not limited thereto, and various shapes may be applied. In short, what is necessary is just to comprise so that the welding location of the muffler bracket 51 and the exhaust muffler 29 may not be exposed to an external appearance design surface, and it can apply widely to a well-known exhaust pipe and exhaust muffler.

  In the above-described embodiment, the case where the present invention is applied to the muffler mounting structure of the motorcycle 1 has been described. However, the present invention is not limited to this, and the present invention can be widely applied to a muffler mounting structure of a small vehicle including other than a motorcycle. . The small vehicles include not only motorcycles (including motor-driven bicycles) but also three-wheeled vehicles and four-wheeled vehicles classified as ATV (rough terrain vehicle), trike, and the like.

1 Motorcycle (small vehicle)
29 Exhaust muffler 29A Muffler body 29B Front cap (cap part)
29C End cap (cap part)
30 Exhaust pipe 51 Muffler bracket 61, 62 Fastening bolt (fastening member)
71 Mounting bracket 73, 74 Extension part (vehicle body side mounting part)
81, 82, 83 Reinforcement bracket 91, 92 Clamping boss S1, SA, SB Clearance

Claims (7)

A muffler (29) connected downstream of the exhaust pipe (30) and connected to the vehicle body via a muffler bracket (51) is provided, and the muffler (29) includes a cylindrical muffler body (29A), In a muffler mounting structure for a small vehicle having a cap portion (29B) for closing the front end of the muffler body (29A),
The muffler bracket (51) has a left-right split structure, and a mounting bracket in which a bracket half on the inner side of the vehicle body is welded and fixed only to the side surface opposite to one outer side surface constituting the appearance design surface of the muffler body (29A). 71), and the bracket half on the outside of the vehicle body is welded and fixed only to the side surface opposite to the one outer surface constituting the appearance design surface of the cap portion (29B), and is fixed to the mounting bracket (71). A reinforcing bracket (81),
The mounting bracket (71) and the reinforcing bracket (81) are welded by bonding together on the side of the fastening boss (91, 92) used for connection to the vehicle body side, while the muffler (29) side contrary position or et away in the middle toward the rearward of the reinforcement bracket (81), between the said mounting bracket (71) muffler body (29A), a gap (SA to open vertically, SB ), And a joint (W4) between the muffler body (29A) and the cap (29B) is positioned in the gap (SA, SB). .   The length from the mounting position of the reinforcing bracket (81) on the vehicle body side to the welding position with the muffler (29) is the length of the welding position between the mounting position of the mounting bracket (71) on the vehicle body side and the muffler (29). The muffler mounting structure for a small vehicle according to claim 1, wherein the muffler mounting structure is configured to be shorter than the length up to.   The muffler attachment structure for a small vehicle according to claim 1 or 2, wherein the muffler (29) has a flat shape that is longer in the vertical direction than the length in the horizontal direction. The mounting parts (73, 74) on the vehicle body side of the mounting bracket (71) are arranged apart from each other in the vertical direction,
The mounting portions (73, 74) are integrally provided with tightening boss portions (91, 92) on the muffler (29) side, and the mounting portions are interposed via the respective tightening boss portions (91, 92). The muffler mounting structure for a small vehicle according to claim 3, wherein (73, 74) are coupled to the vehicle body side.   A plurality of independent reinforcing brackets (82, 83) are provided so as to individually include the tightening boss portions (91, 92), and each reinforcing bracket (82, 83) is welded and fixed to the mounting bracket (71). The muffler mounting structure for a small vehicle according to claim 4.   Among the plurality of the reinforcing brackets (82, 83), the reinforcing bracket (83) near the exhaust pipe (30) is located with respect to the exhaust pipe (30) so as to partially surround the exhaust pipe (30). The muffler mounting structure for a small vehicle according to claim 5, wherein the muffler mounting structure is fixed to the cap portion (29 </ b> B) at a vertical position.   Among the plurality of the reinforcing brackets (82, 83), the reinforcing bracket (82) separated from the exhaust pipe (30) is welded and fixed at an upper and lower intervals with respect to the cap portion (29B). The cap is formed by one welding location (W2B, W2C) and a second welding location (W2A) extending vertically between the upper and lower first welding locations (W2B, W2C) and being welded and fixed to the cap portion (29B). The muffler mounting structure for a small vehicle according to claim 5 or 6, wherein the muffler mounting structure is fixed to the portion (29B).

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