JPH08253186A - Cooling wind discharging structure of motorcycle - Google Patents

Abstract

PURPOSE: To enhance a cooling effect of a radiator by forming inclined parts inclining obliquely backward in a front part of an air box, forming ventilating ports in a main frame on an extension line of these inclined parts, and forming wind discharge ports in cowlings on an extension line of these ventilating ports. CONSTITUTION: A car body front part is covered with a pair of cowlings 16, and an engine 13 is mounted on a front lower part of a main frame 25. An air box 37 is arranged in a space formed between this engine 13 and a fuel tank arranged above it. Inclined parts 38 inclining obliquely backward are formed in a front part of this air box 37, and ventilating ports 39 are formed in the main frame 25 positioned on an extension line of these inclined parts 38. Wind discharge ports 36 and 40 are formed in the respective cowlings 16 positioned on an extension line of its ventilating ports 39. Therefore, since a traveling wind passing through a central part of a radiator 35 is smoothly discharged outside of the cowlings 16, the radiator 35 can sufficiently exhibit a cooling effect.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling air exhaust structure for a motorcycle.

[0002]

2. Description of the Related Art FIG. 5 is a side view of a general motorcycle having a twin-tube type main frame.
FIG. 6 is a sectional view taken along line VI-VI in FIG. 5. The front part of the motorcycle 1 is covered with a streamlined cowling 2 to reduce air resistance during traveling and protect the rider from traveling wind pressure.

The engine 3 of the motorcycle 1 adopts a traveling wind pressure intake system,
An air box 6 is arranged in a space formed between the fuel tank 4 and a pair of left and right main frames 5, and an intake hole 7a of a carburetor 7 is arranged in the air box 6.

Further, the engine 3 of the motorcycle 1 is a water-cooled engine, and a radiator 8 for cooling the cooling water is arranged on the front side of the engine 3. In addition, cowling 2
The traveling wind (cooling wind) that has entered from the front of the vehicle passes through the radiator 8 and is then exhausted from the exhaust port 9 formed on the side portion of the cowling 2.

[0005]

However, since the air box is formed to fill the space formed between the engine, the fuel tank, and the left and right main frames in order to maximize the interior volume of the air box, The running wind that passes through the center of the radiator is difficult to be exhausted rearward, and the radiator cannot exert a sufficient cooling effect.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a cooling air exhaust structure for a motorcycle in which the cooling effect of the radiator is improved.

[0007]

In order to solve the above-mentioned problems, a cooling air exhaust structure for a motorcycle according to the present invention is provided.
As described in claim 1, a pair of left and right twin-tube main frames are provided, a front part of the vehicle body is covered with a cowling, the main frame, an engine mounted on a lower front portion of the main frame, and the engine. An air box is arranged in a space formed between the air tank and a fuel tank arranged above, and in a motorcycle equipped with a radiator in front of the air box, the air box is directed diagonally rearward to the front of the air box. And a ventilation opening is formed in the main frame located on the extension line of the inclination portion, and an exhaust opening is formed in the cowling located on the extension line of the ventilation opening.

[0008]

According to the present invention having the above-described structure, a pair of left and right twin-tube type main frames are provided, the front portion of the vehicle body is covered with the cowling, and the main frame and the engine mounted on the lower front portion of the main frame are provided. And an air box is arranged in a space formed between the fuel tank arranged above the engine and
A slanting part that is slanted rearward is formed in the front part of the air box of a motorcycle equipped with a radiator in front of this air box, and a ventilation port is formed in the main frame located on an extension line of this slanting part. At the same time, since the exhaust port is formed in the cowling located on the extension line of the ventilation port, the traveling wind (cooling wind) passing through the central portion of the radiator is between the engine, the fuel tank, and the main frame. The air is smoothly exhausted to the outside of the cowling without stopping in the space formed in the above, and the cooling effect of the radiator is improved.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a left side view showing an example of a motorcycle to which the present invention is applied. 2 is a plan view of the motorcycle, and FIG. 3 is a front view of the motorcycle. Further, FIG. 4 is a sectional view taken along the line IV-IV in FIG.

1 to 4, the motorcycle 11 is shown.
Has a vehicle body frame 12, and an engine 13 is mounted on the lower front portion of the vehicle body frame 12. A fuel tank 14 is installed above the engine 13, and an operation seat 15 is installed behind the fuel tank 14. The motorcycle 11 has a streamlined cowling 16 covering the front of the vehicle body to reduce air resistance during traveling and protect the rider from traveling wind pressure.

A head pipe 17 is provided in front of the body frame 12, and a steering mechanism 18 is provided on the head pipe 17. The steering mechanism 18 is provided with a pair of left and right front forks 20 and a handlebar 21 that rotatably support the front wheels 19, and the handlebars 21 steer the front wheels 19 rotatably left and right.

A brace 22 for fixing the cowling 16 is provided on the front portion of the head pipe 17, and meters such as a speedometer 23 are attached to a bracket 22a attached to the brace 22. Also, the brace 22
A headlight assembly 24 in which a headlight (not shown) is installed is provided in the front part of the.

By the way, the body frame 12 of the present embodiment.
Is a twin-tube type, for example, a head pipe 1
7 is composed of a pair of left and right main frames 25 that are spread in the left-right direction immediately after 7 and extend rearward in parallel with each other, and a seat rail 26 that extends rearward from the vicinity of the central portion of the main frame 25. A pivot portion 27 is provided on the lower rear portion of the main frame 25. The main frame 25 is, for example, one integrally formed by extrusion or drawing to have a hollow structure, or a pair of frame members obtained by press-molding a metal flat plate into a U-shaped cross section are welded by facing each other, It has a centering structure.

On the other hand, the pivot portion 28 has a pivot shaft 28.
The swing arm 29 is installed on the pivot shaft 28.
Is pivoted about a pivot shaft 28 so as to be swingable, and a rear wheel 30 is rotatably supported at the rear end of the swing arm 29.

The engine 13 is composed of a cylinder 13a and a crankcase 13b, and an exhaust pipe 31a and a muffler 31b forming an engine exhaust system 31 are connected to the front side of the cylinder 13a. Further, a carburetor 33 that constitutes an engine intake system 32 is connected to the rear side of the cylinder 13a. Further, a radiator 35 that constitutes an engine cooling system 34 is arranged in front of the engine 13. The cowlings 16 located at the rear of both sides of the radiator 35 are provided with first exhaust ports 36, respectively.

By the way, the engine intake system 32 of the motorcycle 11 adopts a traveling wind pressure intake system,
The engine 13 and the fuel tank 1 behind the radiator 35
An air box 37 is arranged in a space formed between the main frame 25 and the left and right main frames 25. Then, the air intake hole 33 a of the carburetor 33 is arranged in the air box 37.

As shown in FIGS. 2 and 4, the front portion of the air box 37 is formed with an inclined portion 38 which is inclined from the center toward the left and right diagonally rearward. Also, these inclined portions 3
Ventilation ports 39 are formed in the left and right main frames 25 located on the extension line of 8, respectively. Then, the cowling 16 located on the extension of these ventilation ports 39 has a second
The exhaust ports 40 are formed respectively.

Next, the operation of this embodiment will be described.

When the motorcycle 11 travels, of the traveling wind (cooling wind) that has entered from the front of the cowling 16, the traveling wind that has passed through both sides of the radiator 35 is the arrow A in FIG.
As shown, the air is exhausted from the first exhaust port 36 formed on the side portion of the cowling 16. On the other hand, the traveling wind that has passed through the central portion of the radiator 35 is divided into left and right by an inclined portion 38 formed in the front portion of the air box 37 and then formed in the main frame 25, as shown by an arrow B in FIG. Ventilation port 3
The second exhaust port 4 formed on the side of the cowling 16 through 9
Exhausted from 0.

An inclined portion 38 is formed in the front portion of the air box 37 so as to be inclined obliquely rearward from the center to the left and right, and ventilation holes 39 are formed in the left and right main frames 25 located on the extension lines of these inclined portions 38. And the second exhaust port 40 is formed on the cowling 16 located on the extension of the ventilation port 39, the traveling wind (cooling wind) passing through the center of the radiator 35 is the same as the conventional one. Engine 13 and fuel tank 14
And, since the air is smoothly exhausted to the outside of the cowling 16 without stopping in the space formed between the left and right main frames 25, the radiator 35 can sufficiently exert its cooling effect, and the effect is improved as compared with the conventional one. To do.

[0022]

As described above, according to the cooling wind exhaust structure for a motorcycle according to the present invention, a pair of left and right twin-tube type main frames are provided, the front portion of the vehicle body is covered with the cowling, and the main body is provided. An air box is arranged in a space formed between the frame, an engine mounted on the lower front part of the main frame, and a fuel tank arranged above the engine, and a radiator is arranged in front of the air box. In a motorcycle equipped with the above-mentioned air box, an inclined portion that is inclined obliquely rearward is formed in a front portion of the air box, and a ventilation port is formed in the main frame that is located on an extension line of the inclined portion. Since the exhaust port is formed in the cowling located on the extension line of, the traveling wind passing through the center of the radiator is And charge tank are exhaust air into the cowling out smoothly without stopping the space formed between the main frame, thereby improving the cooling effect of the radiator.

[Brief description of drawings]

FIG. 1 is a left side view of a motorcycle showing an embodiment of a cooling wind exhaust structure for a motorcycle according to the present invention.

FIG. 2 is a plan view of the motorcycle shown in FIG.

FIG. 3 is a front view of the motorcycle shown in FIG.

FIG. 4 is a sectional view taken along line IV-IV in FIG.

FIG. 5 is a left side view of a conventional motorcycle.

6 is a sectional view taken along line VI-VI in FIG.

[Explanation of symbols]

 11 Motorcycle 12 Body Frame 13 Engine 14 Fuel Tank 16 Cowling 25 Main Frame 33 Carburetor 35 Radiator 36 First Exhaust Vent 37 Air Box 38 Slope 39 Vent 40 Second Exhaust

Claims (1)

[Claims] 1. A pair of left and right twin-tube type main frames, the front part of the vehicle body being covered with a cowling,
An air box is disposed in a space formed between the main frame, an engine mounted on a lower front portion of the main frame, and a fuel tank disposed above the engine, and an air box is disposed in front of the air box. In a motorcycle equipped with a radiator, a slanted portion that is slanted rearward is formed in the front portion of the air box, and a ventilation port is formed in the main frame that is located on the extension line of this slanted portion. A cooling air exhaust structure for a motorcycle, characterized in that an exhaust opening is formed in the cowling located on an extension of the ventilation opening.