CN1288032C - Installing structure of mufflex of two-wheel motorcycle - Google Patents

Abstract

The object of the present invention is to distribute the weight of the power unit and the exhaust muffler to the left and right sides of the rear wheel in a motorcycle, and to support the power unit strongly by the exhaust muffler. A two-wheeled motorcycle connected to a body frame (1) at both ends of a horizontal pivot (24) that rotatably supports an arm (26) formed on a casing (10) of the power unit (P) In the car, on the exhaust pipe (16) of the detoured rear wheel (6r) extending from the engine (E), the exhaust muffler placed on the opposite side to the engine (E) across the rear wheel (6r) (17) connection, the exhaust muffler (17) is supported on the end of the exhaust muffler (17) side of the aforementioned boom (26) by the muffler strut (30).

Description

Arrangement structure of exhaust muffler of motorcycle

technical field

The present invention relates to a motorcycle, and particularly to a structure in which an exhaust muffler of an engine is arranged on a power unit. In the two-wheeled motorcycle, a power unit composed of an engine and a transmission that connects the rear wheels to the output shaft is arranged on the left and right sides of the rear wheels, and a horizontal, horizontal, and vertical arm that is formed on the housing of the power unit is rotatably supported. The two ends of the pivot are connected to the body frame.

Background technique

The aforementioned two-wheeled motorcycle is known to the public, for example, as disclosed in JP-A-11-2125. Conventionally, in such two-wheeled motorcycles, the exhaust muffler of the engine is arranged on the left and right sides of the rear wheel together with the power unit, and is attached to an appropriate position of the power unit.

In the arrangement structure of the exhaust muffler in the conventional two-wheeled motorcycle, since the power unit and the exhaust muffler are arranged adjacent to each other, the side opposite to the support of the exhaust muffler relative to the power unit can be firmly performed. , The weight of the power unit including the exhaust muffler is concentrated on the left and right sides of the rear wheels, and it is not easy to set the length of the exhaust pipe connecting the engine and the exhaust muffler to a sufficient length.

In view of the above-mentioned circumstances, an object of the present invention is to provide an arrangement structure of an exhaust muffler for a two-wheeled motorcycle, which can distribute the weight of the power unit and the exhaust muffler to the left and right sides of the rear wheel, and can While supporting the power unit of the exhaust muffler firmly, the length of the exhaust pipe can be set to a sufficient length.

Contents of the invention

In order to achieve the above object, in the arrangement structure of the exhaust muffler of the motorcycle according to the present invention, the power unit composed of the engine and the transmission connecting the rear wheels to the output shaft is arranged on the left and right sides of the rear wheels of the motorcycle. On one side of the power unit, the two ends of the horizontal pivot that rotatably support the boom formed on the casing of the power unit are connected to the body frame. The downstream end of the exhaust pipe is connected to the exhaust muffler arranged on the opposite side to the engine across the rear wheel, and the exhaust muffler is supported on the side of the exhaust muffler of the aforementioned boom through the muffler stay. Ends.

In addition, the said casing corresponds to the crankcase 10 in the Example of this invention mentioned later, and the said connection part corresponds to the connection boss part 31. As shown in FIG.

According to the above-mentioned first feature, the power unit and the exhaust muffler are arranged separately on the left and right sides of the rear wheel, so that the left and right weight balance of the vehicle body can be achieved as much as possible.

In addition, by connecting the downstream end of the exhaust pipe that extends from the engine of the power unit and detours to the front of the rear wheels to the exhaust muffler, it is possible to easily give the exhaust pipe a sufficiently long pipe length, which contributes to The improvement of the output performance of the engine, especially at low and medium speeds, is obtained.

Also, although the exhaust muffler is disposed away from the power unit, by connecting the front end of the muffler stay supporting the exhaust muffler to the end of the boom on the exhaust muffler side, a shorter muffler can be used. The support rod of the exhaust muffler can improve the support rigidity of the exhaust muffler.

In addition to the first feature, the second feature of the present invention is that a pair of upper and lower connecting parts are formed at the front end of the muffler stay while fixing the base end of the muffler stay to the exhaust muffler. , These linking parts are sandwiched from above and below the aforementioned pivot, and are connected to the aforementioned boom through connecting members.

According to the above-mentioned second feature, the load of the exhaust muffler applied to the boom is distributed around the pivot shaft, the load concentrated on the boom is reduced, and the durability thereof can be improved.

Furthermore, the present invention is based on the first or second feature, and its third feature is that a bolt hole having an axis parallel to the pivot shaft is engraved on the end face of the boom on the side of the exhaust muffler, The connecting portion is connected to the boom by screwing and fastening a bolt as a connecting member inserted through the connecting portion from the outside of the vehicle body to the bolt hole.

According to the above-mentioned third feature, the screwing and fastening of the bolts can be easily performed without being interfered by other objects, and the assemblability of the muffler strut to the boom can be improved. The bearing hole of the boom on the shaft and the lower hole of the bolt hole can be formed at one go by multi-axis processing, and the bolt hole can be arranged close to the pivot, so that the boom can be compacted.

Description of drawings

Fig. 1 is a side view of a motorcycle having an arrangement structure of an exhaust muffler according to the present invention.

Fig. 2 is an enlarged side view of an essential part of Fig. 1 .

Fig. 3 is a view of arrow 3-3 in Fig. 2 .

Fig. 4 is a sectional view taken along line 4-4 of Fig. 2 .

Detailed ways

Embodiments of the present invention will be described based on one embodiment of the present invention shown in the drawings.

Fig. 1 is a side view of a two-wheeled motorcycle having an arrangement structure of an exhaust muffler according to the present invention, Fig. 2 is an enlarged side view of an essential part of Fig. 1 , Fig. 3 is a view of an arrow 3-3 in Fig. 2 , and Fig. 4 It is a cross-sectional view taken along line 4-4 in FIG. 2 .

First, in FIG. 1 , a body frame 1 of a motorcycle S is composed of a front frame 1f extending downward from a head pipe 1h that steerably supports a front fork 2 and supporting a pedal surface 3 . The rear end of the front fork 1f extends upwards to support the rear frame 1r of the tool box 4, the passenger seat 5 and the fuel tank 7; the upper and lower ends of the front fork 2 pivotally support the front wheel 6f, A power unit P is swingably suspended on the frame 1r to support and drive a rear wheel 6r and a rear shock absorber 8 is installed between the rear frame 1r and the power unit P. In addition, a bracket 9 for making the vehicle body stand on its own is attached to the front frame 1f. In this way, the two-wheeled motorcycle S is configured as a scooter type.

As shown in FIGS. 2 and 3 , the power unit P is a device configured to house a crankshaft and a transmission mechanism together in the crankcase 10 of the engine E, and is arranged on the left and right sides of the rear wheel 6r. In the illustrated example is configured on the right. Further, a rear wheel 6r is attached to the output shaft 12 of the transmission mechanism protruding from the wall on the rear side of the crankcase 10 .

A carburetor 15 is connected to an upper surface of a cylinder head 13 of the engine E inclined toward the front of the vehicle body through an intake pipe 14 , and an exhaust pipe 16 is connected to the lower surface thereof. The exhaust pipe 16 is largely bent around the front portion of the rear wheel 6r, and connected to the downstream end thereof is an exhaust muffler 17 disposed on the opposite side to the power unit P across the rear wheel 6r.

Next, the suspension device of the power unit P described above will be described with reference to FIGS. 2 to 7 .

As shown in Fig. 3 and Fig. 4, a pair of brackets 21, 21 are welded to the front ends of the support arms 20, 20 on the left and right sides of the rear end portion of the front frame 1f. On these brackets 21, 21, The suspension rod 22 is swingably connected by a first horizontal pivot 23 . The suspension rod 22 has one front arm 22a and a pair of left and right rear arms 22b, 22b, and the front arm 22a is inserted into the rear end portion of the front frame 1f with a buffer rubber 25 interposed therebetween to be supported.

On the one hand, the crankcase 10 of the engine E is integrally formed with a boom 26 . The boom 26 is composed of an arm portion 26a protruding obliquely from the front of the crankcase 10 toward the front of the rear wheel 6r and toward the rotation center plane O of the rear wheel 6r, and a bearing hub 26b. The front end of the arm portion 26a extends left and right, and is arranged horizontally in front of the rear wheel 6r across its rotation center plane O (in other words, the longitudinal center plane of the vehicle body).

Rubber pads 27, 27 are pressed into both ends of the bearing hole of the bearing hub 26b. The bearing hub 26b is disposed between the rear ends of the left and right rear arms 22b, 22b of the suspension rod 22, and the horizontal second pivot shaft 24 of the bearing hub 26b is rotatably supported by the left and right rubber pads 27, 27. Both ends are connected to the two rear arms 22b, 22b. Therefore, the power unit P can swing up and down around the second pivot, and the impact force of the swing from the power unit P acting on the suspension rod 22 is absorbed by the buffer rubber 25 .

The exhaust muffler 17 is supported by the above-mentioned suspension device of the power unit P as follows.

On the exhaust muffler 17, the base end of the muffler strut 30 is welded, and the front end of the muffler strut 30 is formed into upper and lower double-strand parts 30a, 30a, and is fixedly arranged at the front ends of the double-strand parts 30a, 30a. A pair of connection protrusions 31, 31 have an axis parallel to the second pivot shaft 24 described above. On the one hand, at the end portion of the bearing hub 26b of the boom 26 on the side of the exhaust muffler 17, muffler mounting portions 32, 32 bulging up and down are formed with the second pivot 24 interposed therebetween (see FIG. 2 in particular). ). Therefore, the end surface of the bearing hub 26b on the exhaust muffler 17 side is wider than the end surface on the power unit P side by the muffler mounting portions 32 , 32 . A pair of bolt holes 33 , 33 arranged vertically across the second pivot shaft 24 and having an axis parallel thereto are engraved on the end surfaces of the muffler mounting portions 32 , 32 . Furthermore, the bolts 34, 34 inserted through the pair of connection protrusions 31, 31 of the muffler stay 30 from the outside of the vehicle body are screwed and fastened to the pair of bolt holes 33, 33 of the muffler mounting parts 32, 32. According to this, the connection protrusions 31, 31 are fastened to the end surface of the bearing hub 26b.

Next, the action of this embodiment will be described.

When the two-wheeled motorcycle S is running, if the rear wheels 6r rise and fall according to the unevenness of the road surface, the power unit P that supports the rear wheels 6r and is integrally equipped with the boom 26 is supported on the suspension via the muffler stay 30. The exhaust muffler 17 on the arm 26 is integrated and swings up and down around the second pivot 24, and the up and down swing can be damped by the rear shock absorber 8.

However, since the power unit P and the exhaust muffler 17 are arranged on the left and right sides of the rear wheel 6r, respectively, it is possible to achieve a balance in the weight of the left and right sides of the vehicle body as much as possible. In addition, although the power unit P is arranged on the side of the rear wheel 6r, the boom that bears heavy objects such as the rear wheel 6r, the power unit P, and the exhaust muffler 17 is arranged so as to traverse the rotation center plane O of the rear wheel 6r. 26. The unbalanced load on the suspension device including the boom 26 and the second pivot shaft 24 can be avoided as much as possible, so that the riding comfort of the two-wheeled motorcycle S can be achieved.

In addition, since the downstream end of the exhaust pipe 16 that extends from the engine E of the power unit P and detours to the front of the rear wheel 6r is connected to the exhaust muffler 17, it is possible to easily give the exhaust pipe 16 a sufficiently long pipe. Long, can contribute to the improvement of the output performance of the engine E, especially at low and medium speeds.

Furthermore, although the exhaust muffler 17 is disposed away from the power unit P, by connecting the front end of the muffler stay 30 supporting the exhaust muffler to the end of the bearing hub 26b of the boom 26 on the side of the exhaust muffler 17 On the part, a shorter muffler strut 30 can be used, which can improve the support rigidity of the exhaust muffler 17 and ensure its stable support.

In particular, since the connection protrusions 31, 31 of the double-strand parts 30a, 30a of the muffler strut 30 sandwich the second pivot 24, the pair of muffler mounting parts 32, and the bearing hub 26b of the boom 26 from up and down. 32 fastened connection, the load applied to the exhaust muffler 17 on the boom 26 is distributed around the second pivot 24, the load concentrated on the boom 26 is reduced, and the durability can be improved.

In addition, when the muffler strut 30 is attached to the boom 26, the bolts 34, 34 inserted through the connection protrusions 31, 31 from the outside of the vehicle body are screwed and fastened to the bearing hub 26b of the boom 26. In the bolt holes 33, 33 opened on the end faces of the muffler mounting parts 32, 32, the screwing and fastening of the bolts 34, 34 can be easily performed without being disturbed by other objects, and the direction of the muffler strut 30 toward the boom 26 can be easily screwed and fastened. Assemblability is very good.

Furthermore, a pair of bolt holes 33,33 are parallel to the second pivot shaft 24 due to being engraved on the end faces of a pair of muffler mounting parts 32,32 of the bearing hub 26a, and pass through the bearing holes and bolts of the bearing hub 26b. The lower holes of the holes 33 and 33 can be formed at one go by multi-axis processing, and the bolt holes 33 and 33 can be arranged close to the second pivot shaft 24, so that the bearing hub 26b can be compacted.

The present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the spirit thereof. For example, both ends of the muffler stay may be bolted to the exhaust muffler and the boom. In addition, contrary to the above-described embodiment, the muffler stay may be formed integrally with the boom, and the front end of the muffler stay may be fixed to the exhaust muffler with bolts.

As described above, according to the first aspect of the present invention, the power unit composed of the engine and the transmission connecting the rear wheels to the output shaft is arranged on the left and right sides of the rear wheels, and the casing formed on the power unit is rotatably supported. In a two-wheeled motorcycle connected to the body frame on both ends of the horizontal pivot of the boom arm, the downstream end of the exhaust pipe extending from the engine to the rear wheel will be arranged between the rear wheel and the rear wheel. It is connected to the exhaust muffler on the opposite side of the engine, and the exhaust muffler is supported on the end of the aforementioned boom on the side of the exhaust muffler through the muffler brace. According to this, the power unit and the exhaust muffler are behind The left and right sides of the wheels are arranged separately, which can strive for the balance of the left and right weight of the car body. In addition, by connecting the downstream end of the exhaust pipe extending from the engine of the power unit and detouring the front of the rear wheels to the exhaust muffler, it can be achieved. Easily providing the exhaust pipe with a sufficiently long pipe length can contribute to the improvement of the output performance of the engine, especially at low and medium speeds. Also, although the exhaust muffler is disposed away from the power unit, by connecting the front end of the muffler stay supporting the exhaust muffler to the end of the boom on the exhaust muffler side, a shorter muffler can be used. The support rod of the exhaust muffler can improve the support rigidity of the exhaust muffler.

According to the second feature of the present invention, on the basis of the first feature, since the base end of the muffler stay is fixed on the exhaust muffler, a pair of upper and lower joints are formed at the front end of the muffler stay. These connecting parts sandwich the aforementioned pivot from up and down and are connected to the aforementioned boom through connecting parts, so that the load of the exhaust muffler applied to the boom is distributed to the periphery of the pivot, and the energy concentrated on the boom is reduced. Load, can seek to improve its durability.

Furthermore, according to the third feature of the present invention, on the basis of the first or second feature, since a bolt hole having an axis parallel to the pivot shaft is engraved on the end face of the boom on the side of the exhaust muffler , by screwing and fastening the bolts as the connecting parts inserted from the outside of the vehicle body to the aforementioned connecting parts with the bolt holes, the connecting part is connected to the aforementioned boom, and the aforementioned bolts can be easily carried out without being interfered by other items. Assemblability of the muffler strut to the boom can be improved by screwing and fastening the muffler strut. Furthermore, by performing multiple mountings on the bearing hole of the boom supported on the pivot and the lower hole of the aforementioned bolt hole. Shaft processing can be formed at one go, and the aforementioned bolt holes can be arranged close to the pivot, so that the boom can be compacted.

Claims (3)

1. An arrangement structure of an exhaust muffler of a two-wheeled motorcycle, the two-wheeled motorcycle will be composed of an engine (E) and a transmission (T) connected to the rear wheel (6r) on the output shaft (12) The power unit (P) is arranged on the left and right sides of the rear wheel (6r), and the horizontal pivot (24) that rotatably supports the boom (26) formed on the housing (10) of the power unit (P) The two ends are connected on the body frame (1), It is characterized in that at the downstream end of the exhaust pipe (16) extending from the engine (E) and detouring the rear wheel (6r), a row arranged on the opposite side to the engine (E) across the rear wheel (6r) is connected. The gas muffler (17), the exhaust muffler (17) is supported on the end of the exhaust muffler (17) side of the aforementioned boom (26) through the muffler strut (30). 2. The disposition structure of the exhaust muffler of a two-wheeled motorcycle according to claim 1, wherein the base end of the muffler strut (30) is fixed on the exhaust muffler (17) At the same time, a pair of upper and lower connecting parts (31) are formed at the front end of the muffler strut (30), and these connecting parts (31) sandwich the aforementioned pivot (24) from top to bottom, and are connected to each other by connecting parts (34). On the aforementioned boom (26). 3. The disposition structure of the exhaust muffler of a two-wheeled motorcycle as claimed in claim 2, characterized in that, the end face of the exhaust muffler (17) side of the aforementioned boom (26) is engraved with a The bolt hole (33) of the axis parallel to the aforementioned pivot (24) is screwed to the bolt hole (33) by the bolt (34) as a connecting part inserted from the outside of the vehicle body to the aforementioned connecting portion (31). Fasten, connect the connecting part (31) on the aforementioned boom (26).

Images