JP3727641B2 - Motorcycle exhaust system - Google Patents

Description

  The present invention relates to an exhaust device for a motorcycle in which the exhaust device is covered with a cowling.

2. Description of the Related Art A motorcycle in which an exhaust device is covered with a cowling is conventionally known (for example, see Patent Document 1).
JP-A-62-96182

In the above prior art, an exhaust device (such as a silencer ) is provided with a recess in the lower cowling, and the tail end of the silencer ( exhaust muffler ) is continued in this recess.
In this conventional motorcycle exhaust system, the muffler itself can hardly be seen from the outside, and it is difficult to recognize that the muffler is disposed there.
In addition, in a conventional motorcycle exhaust system, if a multi-cylinder engine silencer is assembled , a sufficient capacity of the silencer is required, and an exhaust gas outlet from the silencer is desired. It was.

  SUMMARY OF THE INVENTION An object of the present invention is to make a tail pipe provided in a lower part easily visible from a cowling, while providing a silencer tube portion in the cowling to ensure a good appearance while ensuring capacity.

In the invention according to claim 1, a multi-cylinder engine is arranged between the front and rear wheels, a silencer connected from the engine to a plurality of exhaust pipes is arranged below the engine, and the left and right side surfaces of the silencer and the exhaust pipes are arranged. A motorcycle surrounded by a cowling, wherein the silencer is configured by a cylindrical cylindrical portion that is oblong and obstructed at the front and back of the engine, and is configured by a silencer that is thicker than the exhaust pipe, and the gas outlet of the silencer The tail pipe is provided on the right side of the vehicle body so as to protrude from the cowling, and the silencer has a flat shape with a long width direction.

  According to a second aspect of the present invention, in the first aspect, the tail pipe is located in the vicinity of the rear wheel.

  The invention according to claim 3 is characterized in that, in claim 1, a cover member is provided on a side portion of the engine, and the cowling is attached to the vehicle body at a position where the cover member is exposed to the side.

According to a fourth aspect of the present invention, in the first aspect, the motorcycle includes a swing arm at a rear portion of the vehicle body frame, the swing arm includes a rear cushion at a substantially center of the vehicle body, and the rear portion of the silencer It extends to the vicinity of the cushion.
The invention according to claim 5 is characterized in that, in claim 1, the upper edge of the lower cowl body covering the side surface of the silencer is parallel to the ground and is horizontal .

In the invention according to claim 1, the silencer is constituted by a cylindrical tube portion that is elongated and closed at the front and rear of the engine, and a tail pipe projects from the cowling to the right side of the vehicle body at the gas outlet of the silencer. Since the cylindrical part of the flat-shaped silencer with a long width direction is provided in the cowling, the tail pipe provided at the lower part of the vehicle is easy to see from the cowling while ensuring the capacity and improving the appearance, and Since it is arranged on the right side of the vehicle body, it is possible to suppress the footing when the vehicle is stopped and the influence on the driver before boarding.

  In the invention according to claim 2, since the tail pipe is positioned in the vicinity of the rear wheel, an exhaust sound is generated at a low position of the rear wheel, and the exhaust sound is shielded or mitigated by the rotation of the rear wheel. There is an advantage that an effect that it can be attenuated by buffering with the sound and the rotating sound of the rear wheel can be expected.

  In the invention according to claim 3, the cover member is provided on the side of the engine, and the cowling is attached to the vehicle body at a position where the cover member is exposed to the side. You can produce a design in between.

  In the invention according to claim 4, the motorcycle includes a swing arm at the rear portion of the vehicle body frame, the swing arm includes a rear cushion at the substantially center of the vehicle body, and the rear portion of the silencer extends to the vicinity of the rear cushion. The front and rear length of the silencer can be further secured, the lateral width of the silencer can be reduced, and the cowling can be reduced, so that it can further contribute to a light design and has good footing to the tail pipe. There is an advantage that

The best mode for carrying out the present invention will be described below with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.
FIG. 1 is a side view of a motorcycle employing a cowling structure according to the present invention, and shows the appearance of the motorcycle 10.
The motorcycle 10 includes a front wheel 32 attached to the front portion of the vehicle body frame 20 via a front fork 31, a rear wheel 34 attached to the rear portion of the vehicle body frame 20 via a swing arm 33, and a lower central portion of the vehicle body frame 20. And an air cleaner 53, a fuel tank 55, and a seat 56 attached to the upper center of the longitudinal direction of the body frame 20.

The present invention is characterized in that an in-line four-cylinder engine 40 is disposed between the front and rear wheels 32 and 34 and a silencer 70 (hereinafter referred to as a silencer) is disposed below the engine 40. The silencer 70 is attached to the vehicle body frame 20 or the engine 40.

  Further, the cowling 100 of the motorcycle 10 includes a front cowl 101 that covers the upper part of the front part of the vehicle body, left and right middle cowls 111 that cover the middle part of the front part of the vehicle body (only shown on the right in the figure, and the same applies hereinafter) The left and right lower cowl 121 covering the side surface of the silencer 70 and the rear cowl 131 surrounding the rear part of the vehicle body.

The front cowl 101, the left and right middle cowls 111, and the left and right lower cowls 121 are coupled to each other by screws. More specifically, the cowling 100 can divide the upper front part of the left and right middle cowls (front cowls) 111 with respect to the lower part of the front cowl 101, and the lower rear end part of the middle cowl 111 at the front position of the silencer 70. On the other hand, the front end portion of the lower cowl (rear cowl) 121 can be divided.
The upper edge 121a of the lower cowl 121 is parallel to the ground as shown in FIG.

The front cowl 101 includes a wind screen 102 at the top and a pair of left and right air suction ports 103 at the front.
Further, a recess 112 that is recessed toward the center of the vehicle body is formed at the lower rear end of the middle cowl (front cowl) 111, and a front opening 122 is formed at the front end of the lower cowl (rear cowl) 121. And the depression 112 can be combined to form a large air inlet 123 for cooling the silencer 70.

  Furthermore, this figure shows that the rear fender 140 disposed below the rear cowl 131 is attached to the swing arm 33. In the present invention, the lower edge 132 of the rear cowl 131 is inclined substantially linearly rearward and upward, and the upper surface 141 of the rear fender 140 is inclined substantially linearly rearward and upward so as to be parallel to the lower edge 132 of the rear cowl 131. It is characterized by.

In the figure, 47 is a crankshaft of the engine, 48 is a cover member (crankshaft cover), 91 is a handle, 92 is a mirror, 93 is a headlamp, 94 is a blinker, 95 is a front fender, and 96 is a rear cushion unit. , 97 are cushion links. The rear part of the silencer 70 extends to the vicinity of the cushion link 97.
As apparent from FIGS. 1 and 4, the engine side cover member 48 is exposed to the side of the cowling 100 between the middle cowl 111 and the lower cowl 121.

FIG. 2 is a perspective view of a main part of the intake / exhaust system structure mounted on the cowling structure of the motorcycle according to the present invention.
The intake system 51 of the motorcycle 10 includes a pair of left and right air suction ports 103 provided in the front cowl 101 shown in FIG. 1 and a pair of left and right air ducts (intake ducts) 52 extending rearward from the air suction ports 103. 52 and an air cleaner 53 connected to the ends of these air ducts 52 and 52. The air cleaner 53 is disposed between the pair of left and right main pipes 21 and 21 of the vehicle body frame 20. Reference numeral 22 denotes a head pipe.

The engine 40 is a four-cylinder engine in which four exhaust ports 41 to 44 are arranged in a left and right row in an upper front portion, and includes an oil pan 45 in a lower rear portion.
An exhaust system (exhaust device) 58 of the motorcycle 10 is an exhaust gas through an exhaust pipe 60 (hereinafter referred to as an exhaust pipe) extending from the exhaust ports 41 to 44 of the engine 40 and a silencer 70 connected to the exhaust pipe 60. It is a device that discharges.
As shown and understood in FIG. 1, the left and right sides of the exhaust pipe 60 extending from the silencer 70 and the engine 40 are surrounded by a cowling 100.

  As the silencer 70, a type in which a gas outlet 74 is provided in the vicinity of the gas inlet 73 is employed. The silencer 70 is arranged below the engine 40 with the gas inlet 73 facing the rear wheel 34 side, and the exhaust pipe 60 is extended to the vicinity of the rear wheel 34 so as to be connected to the gas inlet 73 of the silencer 70. I made it.

Here, the four exhaust ports are referred to as a first exhaust port 41, a second exhaust port 42, a third exhaust port 43, and a fourth exhaust port 44 in this order from the left side of the vehicle body (the right side in the figure) to the right side.
The exhaust pipe 60 includes four pipes (first pipe 61, second pipe 62, third pipe 63, and fourth pipe 64) and three collective cylinders (first collective cylinder 65, second collective cylinder 66, and third pipe. A collecting cylinder 67).

  The first pipe 61 having one end connected to the first exhaust port 41 extends to the lower right and then extends to the rear while passing through the right side of the oil pan 45. Similarly, the second pipe 62 having one end connected to the second exhaust port 42 also extends rearward while passing through the right side of the oil pan 45 after extending downward to the right. Then, the other end of the first pipe 61 and the other end of the second pipe 62 are connected to the first collecting cylinder 65 to gather together. The first collecting cylinder 65 extends rearward while passing through the right side of the oil pan 45, and further extends leftward.

  On the other hand, the third pipe 63 having one end connected to the third exhaust port 43 extends to the lower left and then extends to the rear while passing through the left side of the oil pan 45. Similarly, the fourth pipe 64 having one end connected to the fourth exhaust port 44 also extends to the lower left and then extends to the rear while passing through the left side of the oil pan 45. Then, the other end of the third pipe 63 and the other end of the fourth pipe 64 are connected to the second collecting cylinder 66 to gather together. The second collecting cylinder 66 extends rearward while passing through the left side of the oil pan 45.

Further, the other end of the first collecting cylinder 65 and the other end of the second collecting cylinder 66 are connected to the third collecting cylinder 67 to be gathered together. In this way, the four pipes 61 to 64 can be combined into one third collecting cylinder 67. Then, the third collecting cylinder 67 extends rearward and is connected to the gas inlet 73.
The silencer 70 extended as described above is thicker than the exhaust pipe (exhaust pipe) as apparent in FIGS. 1, 2 and 3, and the shape thereof is a flat shape having a long width direction as apparent in FIG. It is.

FIG. 3 is a plan sectional view of the silencer employed in the cowling structure of the motorcycle according to the present invention.
The silencer 70 includes a cylindrical cylindrical portion 71 that is elongated in the front-rear direction, a gas inlet 73 and a gas outlet 74 provided at the rear end 72 of the cylindrical portion 71, and three expansion chambers in the cylindrical portion 71 in the longitudinal direction. It consists of a first partition plate 78 and a second partition plate 79 that partition into 75-77.

In this way, the first expansion chamber 75, the second expansion chamber 76, and the third expansion chamber 77 can be provided in this order in the cylinder portion 71 from the rear end portion 72 to the front (right side in this figure). The first expansion chamber 75 communicates with the gas inlet 73, the third expansion chamber 77 communicates with the first expansion chamber 75 through the first communication pipe 81, and the second expansion chamber 76 communicates with the third expansion chamber 77 through the second communication pipe. The gas outlet 74 is communicated with the second expansion chamber 76 via the third communication pipe 83, and the tail pipe 84 is connected to the gas outlet 74.
As is apparent from FIG. 1, the tail pipe 84 protrudes from the rear right side of the lower cowl 121 of the cowling 100. Further, the tail pipe 84 is located in the vicinity of the side of the rear wheel 34 as apparent from FIG.
The exhaust noise can be attenuated by the expansion action when the exhaust gas enters the first, second, and third expansion chambers 75 to 77.

  FIG. 4 is a front perspective view showing the cowling structure of the motorcycle according to the present invention. As described above, 111 is a middle cowl as a front cowl, 112 is a depression of the middle cowl 111, and 121 is a rear. A lower cowl as a side cowl, 122 is a front opening, 123 is an air guide opening formed by a recess 111 and a whole surface opening 122, 124 (... indicates a plurality, the same applies hereinafter) is a body frame 20 (FIG. 1). This is a set screw for stopping the lower cowl 121.

FIG. 5 is a perspective view from the side of the cowling showing the cowling structure of the motorcycle according to the present invention.
That is, in the cowling structure of the motorcycle according to the present invention, the engine 40 is disposed between the front and rear wheels 32, 34 (see FIG. 1), the silencer 70 is disposed below the engine 40, and the left and right side surfaces of the silencer 70 are In the motorcycle 10 surrounded by the cowling 100, the cowling 100 can be divided at the front position of the silencer 70, and a recess 112 that is recessed toward the center of the vehicle body is formed at the rear end of the middle cowl 111 (front cowl). It can be said that a large air inlet 123 for cooling the silencer 70 is formed by forming a front opening 122 at the front end of 121 (rear cowl) and combining the front opening 122 and the recess 112.

For example, cooling the silencer 70 and the like of the motorcycle 10 (see FIG. 1) using traveling wind is preferable from the viewpoint of environmental protection because it only needs to use natural traveling wind. .
Therefore, the cowling 100 is formed so as to be split into the middle cowl 111 and the lower cowl 121 at the front position of the silencer 70, and a hollow 112 that is recessed toward the center of the vehicle body is formed at the rear end of the middle cowl 111. Opening 122 is formed. Then, the air inlet 123 is formed by combining the recess 112 at the rear end of the middle cowl 111 and the front opening 122 of the lower cowl 121.

That is, by aligning the front opening 122 and the depression 112, for example, the middle cowl 111 can be covered with the lower cowl 121, and the inside can be made difficult to see. As a result, the large air inlet 123 can be formed for cooling the silencer 70, and the silencer can be sufficiently cooled.
Further, a side portion of the crankshaft 47 of the engine 40 is covered with a crankshaft cover 48 (cover member), a flange portion 48a is formed around the cover member 48, and the crankshaft cover 48 and the flange portion 49 are bundled together. Then, the area of the cowling 100 is made small by exposing it from the cowling 100 (see FIG. 1). As a result, a design with a light feeling can be produced by making the cowling 100 look small.

FIG. 6 is a side view of a rear fender employing a motorcycle cowling structure according to the present invention. For example, the design of the motorcycle 10 can be improved by adding functions other than mudguards to the rear fender 140. If so, it is preferable that the design of the motorcycle can be made novel.
Therefore, the rear fender 140 has the lower edge 132 of the rear cowl 131 inclined substantially linearly rearward and upward, and the upper surface of the rear fender 140 is inclined substantially linearly rearward and upward so as to be parallel to the lower edge 132 of the rear cowl 131. It shows that. In the figure, reference numeral 35 denotes a rear wheel shaft, 36 denotes a pivot shaft, and 142 denotes a protrusion formed on the rear fender 140.

  That is, in the rear fender structure of the motorcycle, the lower edge 132 of the rear cowl 131 is substantially rearward and upward in the motorcycle 10 in which the rear part of the vehicle body is surrounded by the rear cowl 131 and the rear fender 140 disposed below the rear cowl 131 is attached to the swing arm 33. It can be said that the upper surface of the rear fender 140 is inclined substantially linearly rearward and upward so as to be parallel to the lower edge 132 of the rear cowl 131.

  In the rear fender structure of the motorcycle, the upper surface of the rear fender 140 is inclined substantially linearly rearward and upward so as to be parallel to the lower edge 132 of the rear cowl 131. It is possible to improve the flow of running wind. As a result, it is possible to add the effect of a rear spoiler that generates downforce in the rear fender 140 and holds the rear wheel 34 downward. Further, by adding the effect of the rear spoiler to the design of the motorcycle 10, the design of the motorcycle 10 can be improved.

  Further, by providing the rear fender 140 with the protruding portion 142 protruding rearward from the rear wheel shaft 35, the appearance design can be improved.

  The swing arm 33 is provided with a rear cushion unit 96 approximately at the center of the vehicle body and between the vehicle body frame 20 (see FIG. 1), and the upper end of the rear cushion unit 96 is coupled to the upper portion of the swing arm 33 so that the rear cushion unit By connecting the upper end of 96 to the lower part of the body frame 20, for example, the upper and lower spaces between the rear wheel 34 and the rear cowl 131 can be opened. As a result, traveling wind can be drawn around the rear fender 140 and the rear fender 140 can exhibit the effect of the rear spoiler.

  Furthermore, by opening the side of the rear fender 140, the traveling wind can be drawn into the side of the rear fender 140, and the rear fender 140 can exhibit the effect of the rear spoiler.

  In the embodiment, as shown in FIG. 5, the air inlet 123 is formed by aligning the front opening 122 and the recess 112, but the recess 112 extends to the rear of the vehicle body, and the air inlet is formed in a duct shape. It may be the one. The cooling efficiency of the silencer can be improved by making the air duct into a duct shape.

  The exhaust device for a motorcycle according to the present invention is suitable for use in a motorcycle equipped with a multi-cylinder engine.

1 is a side view of a motorcycle including an exhaust device according to the present invention. It is a principal part perspective view of the intake-exhaust system structure which comprises the exhaust apparatus which concerns on this invention. It is a plane sectional view of the silencer of the exhaust device concerning the present invention. 1 is a perspective view from the front of a cowling including an exhaust device for a motorcycle according to the present invention. 1 is a perspective view from the side of a cowling of a motorcycle according to the present invention. 1 is a side view of a rear portion of a motorcycle according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Motorcycle, 32 ... Front wheel, 33 ... Rear swing arm, 34 ... Rear wheel, 40 ... Engine, 48 ... Cover member (crankshaft cover), 48a ... Flange part, 60 ... Exhaust pipe, 70 ... Silencer, 84 ... Tail pipe, 96 ... rear cushion unit, 100 ... cowling, 111 ... front cowl (middle cowl), 112 ... depression, 121 ... rear cowl (loa cowl).

Claims (5)

This is a motorcycle in which a multi-cylinder engine is arranged between front and rear wheels, a silencer connected from the engine to a plurality of exhaust pipes is arranged below the engine, and the left and right sides of the silencer and exhaust pipes are surrounded by cowlings. hand,
The silencer is composed of a cylindrical tube portion that is oblong and obstructed at the front and back of the engine, and is composed of a silencer that is thicker than the exhaust pipe, and a tail pipe on the right side of the vehicle body at the gas outlet of the silencer Projecting from the cowling,
The shape of the silencer is a flat shape having a long width direction.
Exhaust system for motorcycles, wherein a.   The exhaust device for a motorcycle according to claim 1, wherein the tail pipe is located in the vicinity of the rear wheel.   The exhaust system for a motorcycle according to claim 1, wherein a cover member is provided on a side portion of the engine, and the cowling is attached to a vehicle body at a position where the cover member is exposed to the side.   The motorcycle includes a swing arm at a rear portion of a vehicle body frame, the swing arm includes a rear cushion at a substantially center of the vehicle body, and a rear portion of the silencer extends to the vicinity of the rear cushion. Item 2. An exhaust system for a motorcycle according to Item 1. The exhaust device for a motorcycle according to claim 1, wherein the upper edge of the lower cowl body that covers the side surface of the silencer is parallel to the ground and is horizontal.

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