JPH0239856Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an exhaust system for a small vehicle, and is intended to suppress vibrations of the muffler and tail pipe, and to improve strength.

In small vehicles, especially small vehicles with a passenger capacity of 1 to 2 people, the biggest challenge is how to reduce the vehicle weight because the engine output is small. There is also the problem of having sufficient strength under these conditions and also having to consider vibration resistance. In terms of vibration resistance, the mounting structure of the muffler portion disposed near the engine, which is the source of vibration, is particularly problematic.

The purpose of this invention is to provide an exhaust system for small vehicles that has a simple structure, suppresses vibrations in the muffler part, and has improved durability so that it can be installed in a small space of a small vehicle. be.

Next, one embodiment of this invention will be explained with reference to the drawings. In Fig. 1, 1 is a small vehicle, which is constructed by attaching a vehicle body 3 made of synthetic resin to a body frame 2 made of pipe material. It is something that The front part of the body frame 2 is horizontal, and the almost central part is bent diagonally upward and then extends rearward.A bracket 4 provided at the bent part connects the front pipe 6 of the swing arm 5. I am starting to receive this. An engine unit 7 is mounted on the swing arm 5. 8 is the front wheel,
9 is a rear wheel, 10 is a steering wheel, 11 is a seat, and 12 is a radiator.

FIG. 2 is an enlarged view of the engine unit 7 in FIG. 1, and FIG. 3 is a plan view thereof. As shown in these figures, the swing arm 5 is formed by attaching a substantially U-shaped pipe to the rear of a front pipe 6 parallel to the axle 13, and connects a bracket 14 provided at the center of the rear part to the vehicle body. A shock absorber (not shown) provided between the rear end of the frame 2 allows the swing arm 5 to be moved to the front pipe 6.
It is designed to absorb the shock when rotating around the fulcrum.

An engine unit 7, which includes an engine 15 and an axle 13, is supported on the swing arm 5. The engine 15 has a cylinder 17 protruding forward from a crankcase 16. An exhaust manifold 18 extends slightly upward and rearward from the side of the cylinder 17. The front ends of the cylindrical muffler 19 arranged as shown in FIG. The front end of a tail pipe 20 is connected to the rear end of the muffler 19, and the tail pipe 20 extends downward and rearward from the rear end of the muffler 19. It opens rearward at a position lowered by a distance l (approximately 50 to 200 mm). 21 is an air cleaner, and 22 is a carburetor.

As shown in FIG. 4, a muffler mounting boss 23 is provided on one side of the upper part of the crankcase 16, and a bracket 24 welded to the side surface of the muffler 19 is attached to the muffler mounting boss 23 to hold bolts 25 and nuts. It is concluded by 26. As a result, the central part of the muffler 19 is connected to the crankcase 1.
6.

In order to fit within the limited space of a small vehicle, the engine 15 is supported on the swing arm 5 with the cylinder 17 protruding forward from the crankcase 16, and the muffler 19 is mounted on the side of the crankcase 16. Crankcase 16 above
It is arranged so that it extends parallel to the rear, making it compact. The engine 15 and the muffler 19, which are sources of vibration, are connected together by supporting at two points, the front end and the center of the muffler 19, so that the strength of the muffler 19 against vibration can be maintained and noise can be reduced. There is. Furthermore, tail pipe 20
Since the tail pipe 20 extends downward and rearward from the muffler 19, the rear end of the tail pipe 20 can be lowered below the lower part of the vehicle body 3, and tar in the exhaust gas does not adhere to the vehicle body 3.

[Brief explanation of drawings]

Figure 1 is a side view of a small vehicle with this invention.
2 is an enlarged side view of the engine unit shown in FIG. 1, FIG. 3 is a plan view of FIG. 2, and FIG. 4 is a sectional view showing the muffler mounting portion. 1...Small vehicle, 5...Swing arm, 15
...Engine, 16...Crankcase, 17...
...Cylinder, 18...Exhaust manifold, 19...Muffler, 20...Tailpipe, 2
3...Muffler installation boss, 24...Bracket.

Claims (1)

[Scope of utility model registration request] The engine is supported on the swing arm with the cylinder protruding forward from the crankcase,
An exhaust manifold extends slightly upward and rearward from the side of the cylinder, and the exhaust manifold includes a cylindrical pipe disposed slightly above the side surface of the crankcase and extending rearward parallel to the crankcase. The front ends of the muffler are joined together, the central part of the muffler is integrally attached to the crankcase by a bracket, the front end of a tail pipe is joined to the rear end of the muffler, and the tail pipe extends downward from the muffler. An exhaust system for a small vehicle characterized by extending to the rear.