JPS59303Y2 - motorcycle sound insulation device - Google Patents

Description

[Detailed explanation of the idea] This invention relates to a sound insulation device for a motorcycle.

Motorcycles mainly use air-cooled engines.

Then, engine combustion noise and the like pass through the cylinder wall and are generated.

Particularly in the case of air cooling, a large number of thin cooling fins are provided upright on the cylinder and cylinder head, and these cooling fins resonate and amplify the noise.

These can be achieved by narrowing anti-vibration rubber around the cooling fins, etc.
Although noise can be reduced, there are limits.

This invention has been improved in view of these points, and an embodiment of the invention shown in the drawings will be described below.

An engine 3 is mounted below a fuel tank 2 provided so as to straddle the front upper part of a vehicle body 1, and a cylinder 4 and a cylinder head 5 protrude upward.

Accordingly, in the present invention, both sides of the lower part of the fuel tank 2 are extended 6 downward.

In this case, as shown in FIG.
Alternatively, as shown in FIG. 3, the outer plate 7 and inner plate 8 of the fuel tank 2 may be extended 6.

The extension 6 covers both left and right sides of the cylinder 4 and cylinder head 5.

Then, a sound absorbing plate 9 is attached to the lower surface of the fuel tank 2 and inside the extension 6 using adhesive or the like.

10 is a seat, 11 is a carburetor, and 12 is an air cleaner.

The effect will be explained.

When the engine 3 is operated, noise such as combustion noise is emitted from the cylinder 4 and cylinder head 5.

However, since it is covered from the top to the side by the fuel tank 2 and the extension 6 of the fuel tank 2, it can be sound-insulated, and the sound-absorbing plate 9 can absorb the sound, preventing noise from being radiated to the outside, making it quiet. become.

Furthermore, since the front and rear of the cylinder 4 and the cylinder head 5 are open, they do not interfere with the flow of running air and do not harm cooling.

Since the noise that escapes to the rear escapes to the rear while the vehicle is running, it does not affect the driver much.

As explained above, this invention, in a motorcycle in which the engine is mounted below the fuel tank, extends both sides of the lower part of the fuel tank downward to cover both sides of the engine cylinder. Since the sound-absorbing plate is attached from the top to the side of the engine cylinder and cylinder head, it can be covered by the fuel tank and its extension, providing sound insulation. Since noise can be absorbed by the sound-absorbing plates placed inside, the noise emitted to the outside can be reduced.

Furthermore, since the wind flows in the front and rear directions, it does not harm cooling.

Moreover, since the part that covers the engine cylinder etc. is formed by an extension part that is integrally formed with the fuel tank, it can be attached to the vehicle body automatically by attaching the fuel tank, making it extremely easy to install. The number of parts does not increase.

[Brief explanation of drawings]

1 and 2 show one embodiment of the present invention, FIG. 1 is a side view, FIG. 2 is a sectional view taken along arrow A in FIG. 1, and FIG. 3 is another embodiment of the present invention. This is a diagram equivalent to Figure 2. 2...Fuel tank, 3...Engine,
4...Cylinder 6...Extension part, 9
...Sound absorbing board.

Claims (1)

[Scope of utility model registration request] In a motorcycle with an engine mounted below the fuel tank, both sides of the lower part of the fuel tank are extended downward to cover both sides of the engine cylinder, and a sound absorbing plate is attached to the lower surface of the fuel tank and the extended part. Features a motorcycle noise device.