JP2723311B2 - Exhaust system for saddle type vehicle - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a saddle type vehicle, and more particularly to an exhaust system connected to an internal combustion engine.

2. Description of the Related Art Conventionally, as an exhaust structure in a saddle-ride type vehicle such as a motorcycle or a motorcycle, an internal combustion engine is arranged at a substantially middle portion in a longitudinal direction of a vehicle body, and an exhaust pipe connected to the internal combustion engine is provided. And the exhaust pipe is connected to a silencer disposed on the rear side of the vehicle body (see Japanese Patent Publication No. 144553/144).

This is because, during operation of the vehicle, the muffler is heated to a high temperature, so that the muffler is exposed to the outside as much as possible to actively contact the traveling wind when the vehicle travels, thereby cooling the muffler. This is a measure taken in order to carry out efficiently.

[Problems to be Solved by the Invention] In the above-described conventional technology, since the muffler is provided on the side of the vehicle body, the increase in the capacity of the muffler itself is limited by the limitation of the vehicle body width. Not only do they have to keep enough space between the silencer and the occupants,
Problems such as a limitation in the degree of freedom of the layout occur.

Therefore, conventionally, it is desired to deal with these inconveniences, and the present invention is intended to solve such a problem which has been left in the past.

Means for Solving the Problems According to the present invention, an internal combustion engine is disposed at the center of a vehicle body having front and rear wheels, an exhaust pipe connected to the internal combustion engine, and a muffler connected to the exhaust pipe. And a rear cowl disposed behind a seat, the muffler disposed inside the rear cowl, and
An air guide path for guiding traveling wind is provided between the rear cowl and the muffler, and an exhaust pipe connected to the muffler is connected to the internal combustion engine through a lower portion of the seat. With this configuration, even when the silencer has a large capacity, the silencer does not bulge left and right in the seat portion, and the degree of freedom of the riding posture of the user can be improved.

Further, since the muffler is located behind the seat, it can be disposed so as to protrude outward from the seat. In this case, the silencer can have a larger capacity.

Further, the rear cowl has a cross-sectional shape surrounding the silencer, and an opening communicating with the inside and outside of the rear cowl is formed in an upper or lower portion of the silencer, so that a ventilation volume for silencer cooling in the rear cowl is provided. Can also be increased.

Also, an exhaust collecting chamber may be provided between the internal combustion engine and the rear wheel, and an exhaust pipe below the seat may be bent and connected to the exhaust collecting chamber.

Further, the exhaust pipe located below the seat is formed in a flat shape so as to be wider in the width direction of the vehicle body, to prevent interference with the exhaust pipe due to swinging of the rear wheel, and to secure a cross-sectional area of the exhaust pipe. can do.

In addition, the rear wheel is pivotally supported on the vehicle body by a cantilever swing arm so as to be vertically swingable, and the exhaust pipe is bent from the lower portion of the seat to a front portion of the rear wheel to extend. Is also good. As a result, the rear wheel can be attached and detached from the side, thereby facilitating operations such as maintenance.

Embodiment An embodiment of the present invention will now be described with reference to FIGS.
A description will be given based on the drawings.

FIG. 1 shows a motorcycle as a saddle-ride type vehicle to which the present embodiment is applied, a vehicle body frame 2, a front fork 3 rotatably mounted in front of the vehicle body frame 2, and a front fork. A steering wheel 4 mounted on an upper end of a fork 3, a front wheel 5 rotatably mounted on a lower end of the front fork 3, an internal combustion engine 6 suspended below a lower part of the body frame 2, A swing arm 7 swingably mounted to the lower rear of the frame 2, a rear wheel 8 rotatably mounted to a swing end of the swing arm 7, and an internal combustion engine above the body frame 2; Fuel tank 9 mounted above engine 6
A seat rail 10 extending upward from the rear upper portion of the vehicle body frame 2 to the rear wheel 8, and a seat 11 mounted at a position above the seat rail 10 behind the fuel tank 9. A rear cowl 12 fixed to the seat rail 10 behind the seat 11, an exhaust pipe 13 connected to the internal combustion engine 6, and a collecting chamber 14 connected downstream of the exhaust pipe 13 are provided. , This collective chamber 14
A rear exhaust pipe 15 extending from the rear exhaust pipe 15, and a muffler 16 connected to the downstream end of the rear exhaust pipe 15.
13 and collecting chamber 14, rear exhaust pipe 15, and silencer 16
The exhaust structure of this embodiment is applied to an exhaust system composed of

More specifically, the internal combustion engine 6 has its cylinder 17
(17a, 17b) are V-type four cylinders distributed in the front-rear direction, and the exhaust pipe 13 is composed of a pair of exhaust pipes 13a for a front cylinder 17a and a pair of exhaust pipes 13b for a rear cylinder 17b. Book is provided.

The collecting chamber 14 is disposed behind the internal combustion engine 6 and below the pivot portion 18 of the swing arm 7, and has a flat shape that is wide in the width direction of the vehicle body.
On its front end surface, a pair of exhaust pipes 13a for the front cylinder 17a is provided.
Is communicated after being routed below the internal combustion engine 6, and a pair of exhaust pipes 13 b for the rear cylinder 17 b are arranged on the right rear upper surface after being routed rearward of the internal combustion engine 6. Has been communicated to.

On the other hand, as shown in FIG. 2, the rear cowl 12 is formed to be wider than the seat 11, and the rear cowl is provided at the front end faces on both sides thereof and a substantially central portion of the upper surface in the width direction.
Air inlets 19 and 20 communicating with each other in 12 are formed,
Further, the rear end face is formed as a louver-shaped opening 21.

The lower portion of the rear cowl 12 is opened as shown in FIG. 3, and is closed by mounting a rear fender 22 provided above the front and rear rear wheels 8, and therefore,
The rear cowl 12 is formed in a cylindrical shape so as to surround the muffler 16.

A concave portion 22a is formed in the rear fender 22 at a position corresponding to the rear wheel 8 along the longitudinal direction, and an exhaust port for communicating the inside of the rear cowl 12 to the outside is formed on both sides of the concave portion 22a. 23 are formed.

As shown in FIGS. 1 to 3, the silencer 16 has an outer shape substantially conforming to an inner surface shape of a cavity formed by the rear cowl 12 and the rear fender 22, and Are formed so as to form air guide passages 24 at substantially predetermined intervals over the entire circumference.

Further, a rear exhaust pipe 15 that connects the silencer 16 and the collecting chamber 14 is connected to a substantially central portion of a front end surface of the silencer 16 and an exhaust pipe 13a for a rear cylinder 17b of the collecting chamber 14. After being raised substantially vertically from the collecting chamber 14, it is bent along the seat rail 10 and connected to the muffler 16.

As shown in FIG. 4, a portion of the rear exhaust pipe 15 along the seat rail 10 has a flat shape so as to be wide in the width direction of the vehicle body.

As shown in FIG. 5, in this embodiment, the swing arm 7 includes a base 7a that covers the collecting chamber 14,
A support 7b extends from the base 7a to the left side of the rear wheel 8.

The base 7a is formed with a cutout 7c for avoiding interference with a pair of exhaust pipes 13b and a rear exhaust pipe 15 connected to the collecting chamber 14, and a through hole 25 along the vertical direction is formed. A link mechanism 26 is mounted on the lower surface of the rear cushion unit 27 that is inserted through the through-hole 25 so as to be located below the through-hole 25 on the lower surface. The lower ends are connected.

As shown in FIG. 1, the upper end of the rear cushion unit 27 is supported by a bracket 28 provided continuously above the rear end of the body frame 2.

Next, the operation of the exhaust device according to the present embodiment will be described.

First, in the exhaust device of the present embodiment, the rear cowl 12 is disposed behind the seat 11, the muffler 16 is disposed inside the rear cowl 12, and the rear exhaust pipe 15 connected to the muffler 16 is seated.
Since the silencer 16 is bent downward at the lower portion of the seat 11 and is connected to the internal combustion engine 6, even when the silencer 16 has a large capacity, the silencer 16 swells right and left at the seat 11. And the degree of freedom of the riding posture of the user can be improved.

In addition, the silencer 16 is arranged inside the rear cowl 12 and extends beyond the seat 11, so that the width of the silencer 16 can be increased while suppressing the expansion of the vehicle body in the width direction. As a result, the capacity of the silencer 16 can be increased.

Further, the rear cowl 12 is provided with a swelling portion 12a in the left-right direction, and a wind guide port 19 is formed on the front surface of the swell portion 12a, and an exhaust port 21 is formed on the rear face of the rear cowl.
The side of the silencer 16 at the rear of the rear exhaust pipe 15 is arranged along the cooling passage connecting the
Cooling air can be passed linearly in the front-rear direction, and ventilation is good, hot air is hard to stay around the silencer 16, and a large amount of cooling air can be concentrated, so the cooling performance of the silencer 16 Can be improved.

Also, since the cross-sectional shape of the rear cowl 12 is shaped to surround the muffler 16, the airflow opening 20 is formed at the upper part of the rear cowl 12, and the opening 23 is formed at the rear fender 22 mounted at the lower part of the rear cowl 12. Thus, the airflow in the rear cowl 12 can be increased, and the cooling performance of the muffler can be further improved.

Further, a collecting chamber 14 is provided between the internal combustion engine 6 and the rear wheel 8, and a rear exhaust pipe 15 provided below the seat 11 is connected to the collecting chamber 14. Interference between the rear wheel 15 and the rear wheel 8 can be prevented, and the space efficiency can be improved.

Also, a rear exhaust pipe 15 located below the seat 11
Is flattened so as to be wider in the width direction of the vehicle body, so that interference between the rear exhaust pipe 15 and the rear wheel 8 can be prevented from this point as well. As a result, the rear exhaust pipe 15 connected to the muffler 16 can be arranged at a substantially central portion of the vehicle body, and can be arranged at a position where a shield exists between the rear exhaust pipe 15 and an occupant. Thermal measures are easy.

Also, the rear wheel 8 is pivoted by a cantilevered swing arm 7,
Since the vehicle body is pivotally supported in the vertical direction and the rear exhaust pipe 15 extends in the vertical direction in front of the rear wheel 8, the rear wheel 8 can be detached from the side. , Maintenance is easy.

Also, the rear cowl 12 is formed wider than the seat 11,
Since the silencer 16 is disposed in the rear cowl 12 and the silencer 16 is formed along the inner surface of the rear cowl 12, the silencer is suppressed while suppressing an increase in the protrusion amount in the width direction of the vehicle body.
The width of the silencer 16 is increased, and as a result, the capacity of the silencer 16 can be increased.

Further, the space between the muffler 16 and the occupant sitting on the seat 11 is shielded by the rear cowl 12, so that heat transfer to the seat 11 is suppressed as much as possible.

Therefore, the degree of freedom in setting the interval between the seat 11 and the silencer 16 is increased, and the degree of freedom in design is increased.
The appearance is improved by housing the 16 in the rear cowl 12.

Further, since the lower portion of the rear cowl 12 is closed by the rear fender 22, the shielding from the outside of the muffler 16 is reliably performed, and a cylindrical air guide path 24 is formed around the muffler 16 so that the rear cowl 12 is formed. The flow of the traveling wind guided into the inside of the muffler 16 is reliably made to follow the outer peripheral surface of the muffler 16, so that the cooling performance of the muffler 16 is enhanced.

In this case, it is not necessary to use the wide silencer 16, and the effect does not change even with a normal cylindrical silencer.

In addition, since the rear fender 22 is mounted using the rear cowl 12, a dedicated member is not required when mounting the rear fender 22, and the configuration is simplified.

Note that the shapes, dimensions, and the like of each component shown in the above-described embodiment are merely examples, and can be variously changed based on the structure of the vehicle to be applied, design requirements, and the like.

[Effects of the Invention] As described above, according to the present invention, the following excellent effects can be obtained.

According to the present invention, a rear cowl is provided behind a seat, the muffler is provided inside the rear cowl, and a wind guide path for guiding traveling wind is provided between the rear cowl and the muffler, and the muffler is connected to the muffler. Since the exhaust pipe is connected to the internal combustion engine through the lower portion of the seat, the rear cowl is not affected by the heat of the muffler, and the rear cowl does not need to be made of a heat-resistant component material, or the vicinity of the rear cowl is not required. It is no longer necessary to provide a dedicated cooling mechanism for the device. In addition, since the traveling wind can be sent around the muffler, the cooling efficiency of the muffler is increased, and as a result, the cooling efficiency of the entire exhaust system is increased,
The engine output can be improved. Further, even when the silencer has a large capacity, the silencer does not bulge left and right in the seat portion, and the degree of freedom of the riding posture of the user can be improved.

Further, since the silencer is arranged wider than the seat, the silencer can have a larger capacity.

Also, the rear cowl has a cross-sectional shape surrounding the muffler, and an opening communicating with the inside and outside of the rear cowl is formed at an upper portion or a lower portion thereof.
It is possible to increase the amount of air flow in the rear cowl and further improve the cooling performance of the rear part of the exhaust pipe.

Further, an exhaust collecting chamber is disposed between the internal combustion engine and the rear wheel, and the exhaust pipe below the seat is bent and connected to the exhaust collecting chamber, so that interference between the exhaust pipe and the rear wheel is prevented. , Space efficiency can be improved.

Further, since the exhaust pipe located below the seat is formed flat so as to be wide in the width direction of the vehicle body, it is possible to prevent interference between the rear wheel and the exhaust pipe. Can be arranged substantially in the center of the vehicle body, and the exhaust pipe can be arranged at a position where an obstruction exists between the vehicle and the occupant, thereby facilitating thermal measures for the exhaust system.

Also, since the rear wheel is pivotally supported on the vehicle body by a cantilever swing arm so as to be swingable in the vertical direction, and the exhaust pipe is bent and extended from the lower part of the seat to the front part of the rear wheel. The rear wheel can be attached to and detached from the side, which facilitates maintenance and other operations.

[Brief description of the drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a side view of a motorcycle, FIG. 2 is a plan view of the same, FIG. 3 is II in FIG.
FIG. 4 is a cross-sectional view of the rear exhaust pipe taken along the line I-III, FIG. 4 is a cross-sectional view of the rear exhaust pipe, and FIG. 1 ... motorcycle, 11 ... seat, 12 ... rear cowl, 15 ... rear exhaust pipe (exhaust pipe), 16 ... silencer, 19 ... air inlet.

Claims (6)

(57) [Claims] A saddle-ride type in which an internal combustion engine is disposed in the center of a vehicle body having wheels at the front and rear, and an exhaust pipe connected to the internal combustion engine and a muffler connected to the exhaust pipe are provided. An exhaust device for a vehicle, wherein a rear cowl is disposed behind a seat, the muffler is disposed inside the rear cowl, and
An exhaust in a saddle-ride type vehicle, wherein an air guide path for guiding traveling wind is provided between a rear cowl and a muffler, and an exhaust pipe connected to the muffler is connected to the internal combustion engine through a lower portion of the seat. apparatus. 2. The exhaust device for a saddle-ride type vehicle according to claim 1, wherein said muffler is disposed so as to protrude outward from said seat. 3. The rear cowl has a cross-sectional shape surrounding the muffler, and an upper or lower part thereof has
3. The exhaust device for a saddle-ride type vehicle according to claim 1, wherein an opening communicating the inside and outside of the rear cowl is formed. 4. An exhaust collecting chamber is disposed between the internal combustion engine and the rear wheel, and an exhaust pipe below the seat is bent and connected to the exhaust collecting chamber. 2. The exhaust device for a saddle-ride type vehicle according to claim 1. 5. The exhaust system according to claim 1, wherein the exhaust pipe located below the seat has a flat shape so as to be wide in the width direction of the vehicle body. apparatus. 6. The rear wheel is pivotally supported on a vehicle body by a cantilever type swing arm so as to be swingable in a vertical direction, and the exhaust pipe extends from a portion under the seat to a portion in front of the rear wheel. The exhaust device for a saddle-ride type vehicle according to claim 1, wherein the exhaust device is provided.