JP2002145155A - Engine cooling wind introducing structure for motorcycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an engine cooling wind introducing structure for a motorcycle capable of effectively introducing traveling wind to an engine to improve the cooling performance. SOLUTION: In a motorcycle having a leg shield 19 for covering the side of the engine 16, a wind guide part 19c is formed on at least a side part 19a having the ignition plug 16b of the engine 16 arranged thereon, and the traveling wind carrying on the outer side from a front fork 14 is guided to the vicinity of the ignition plug 16b by the wind guide part 19c.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved engine cooling structure in a motorcycle having a leg shield.

[0002]

2. Description of the Related Art Conventionally, in a motorcycle of this type, an air-cooled engine is mounted on a vehicle body frame substantially horizontally with a cylinder head facing forward, while covering the side of the cylinder head of the engine. Some have leg shields.

[0003]

However, in such a conventional motorcycle, if the body on which the engine is mounted is of an underbone type having a leg shield, the engine cooling performance tends to be a problem.

That is, the side of the engine is covered with a leg shield, and the body frame is close to the upper part of the engine. This is because the projection area from the front is narrow and, furthermore, since it is arranged close to the front fender, a sufficient amount of cooling air does not hit.

If the height of the seat is increased to improve the airflow, the elevating and lowering of the seat deteriorates, and if the airflow is improved, the electric components such as a battery disposed behind are damaged by heat. In addition, if the distance from the front fender is increased, problems such as an increase in the wheelbase and weight distribution occur.

When air is to be blown in from above the engine in order to increase the amount of air flow, a large air cleaner is disposed near the leg shield and the front fender. .

On the other hand, when observing the flow of the wind, it can be seen that the wind blown outside by the front fork further hits the rear leg shield and flows further outside. Was not hit.

[0008] Under such circumstances, when the output of the engine is increased, the amount of heat generated is increased, so that there is a problem that the performance decreases due to insufficient cooling and the output cannot be increased.

It is an object of the present invention to provide an engine cooling air introduction structure for a motorcycle, which effectively guides a running wind to an engine to improve cooling performance.

[0010]

Means for Solving the Problems In order to achieve the object, an invention according to claim 1 is directed to a motorcycle having a leg shield covering a side of an engine, wherein the leg shield has at least the engine. An engine cooling air introduction for a motorcycle, wherein a wind guide portion is formed on a side portion on a side where the spark plug is disposed, and the running wind flowing outside the front fork is guided to the vicinity of the spark plug by the wind guide portion. It is characterized by having a structure.

According to a second aspect of the present invention, in addition to the effect of the first aspect, the air guide portion has a concave shape recessed toward the rear of the vehicle, and a bottom surface of the concave portion is located on the side of the ignition plug. An inclined surface that is inclined toward the engine is characterized in that a running wind flowing outside the front fork on the inclined surface is guided to the vicinity of the ignition plug.

According to a third aspect of the present invention, in addition to the effect of the first aspect, the wind guide section has a duct shape, and introduces a traveling wind from a suction port formed at one end of the airflow section. The air can be blown from the outlet formed at the other end toward the vicinity of the ignition plug.

According to a fourth aspect of the present invention, in addition to the effect of the third aspect, the opening area of the outlet is smaller than the opening area of the suction port.

[0014]

Embodiments of the present invention will be described below.

[First Embodiment of the Invention] FIGS. 1 to 3 show a first embodiment of the present invention.

First, the structure will be described. The motorcycle according to this embodiment is a so-called underbone type vehicle, and a head pipe 13 for rotatably supporting a steering shaft 12 is provided at a front portion of a body frame 11. Below the head pipe 13, a pair of left and right front forks 1 fixed to the steering shaft 12 is provided.
The front wheel 15 is supported between the front forks 14.

The vehicle body frame 11 includes a front wheel 1
5, an air-cooled engine 16 is mounted substantially horizontally with the cylinder head 16 a facing forward, and a leg shield 19 is disposed on the side of the cylinder head 16 a of the engine 16. I have.

Further, in the engine 16, as shown in FIG. 3, a spark plug 16b is disposed on the right side of the cylinder head 16a in a plan view, and between the cylinder head 16a and the front wheel 15 is provided. A front fender 20 is provided.

Further, the leg shield 19 is
As shown in FIG. 2, when viewed from the front of the vehicle, both side portions 19 a extending downward are formed on both sides of the front wheel 15,
The lower end 19b side of the both side portions 19a is located so as to cover the side of the cylinder head 16a.

At the lower end 19b of one side 19a of the leg shield 19 on which the ignition plug 16b is disposed, a wind guiding air flowing outside the front fork 14 is guided to the vicinity of the ignition plug 16b. Part 19c
Are formed.

The air guide 19c has a concave shape that is recessed toward the rear of the vehicle, and an inclined surface 19d that guides the running wind is formed on the bottom surface of the concave. The vertical width H of the concave shape (see FIG. 2).
) Is set substantially equal to the vertical width of the cylinder head 16a. The inclined surface 19d is inclined toward the ignition plug 16b so that the vehicle outer end 19e is set at a position outside the front fork 14 and guides the wind toward the ignition plug 16b toward the inside. It is formed.

In this manner, the temperature of the ignition plug 16 of the engine 16 tends to be particularly high. However, when the vehicle is running, the traveling wind is directed by the wind guide portion 19c to the ignition plug 1.
Since it is possible to guide and hit the vicinity of 6, the engine cooling performance can be improved. In this case, as shown in FIG. 3, the brake device 2 of the front wheel 15 is located near the rear of the front fork 14 on the side where the spark plug 16 is provided.
2, the direction of the strike wind changes outward to avoid this part (see the arrow in FIG. 3). However, the outer end 19e of the inclined surface 19d is
The front fork 1
A large amount of running wind flowing outside the guide plug 4 can be guided to the vicinity of the ignition plug 16b through the wind guide portion 19c.

As a result, even if the engine 16 is arranged horizontally, the cooling performance can be improved, so that the output of the engine 16 can be increased without impairing the overall layout of the motorcycle.

Moreover, by integrally molding the air guide portion 19c with the leg shield 19, the engine cooling performance can be improved without increasing the number of parts.

Second Embodiment FIGS. 4 to 6 show a second embodiment of the present invention.

Embodiment 2 of the present invention is directed to a
Are different from those of the first embodiment.

That is, the air guide section 19 of the second embodiment
g has a curved cylindrical shape with a rectangular cross section,
9h is located outside the front fork 14 and opens toward the front of the vehicle, and the outlet 19i faces the periphery of the spark plug 16b. As shown in FIG. 6, the width B2 of the outlet 19i is smaller than the width B1 of the inlet 19h, and the opening area of the outlet 19i is smaller than the opening area of the inlet 19h.

As described above, the wind guide 1 is attached to the leg shield 19.
By forming 9g, the running wind flowing outside the front fork 14 and the brake device 22 as shown by an arrow in FIG. 6 can be guided from the suction port 19h into the wind guide portion 19g, and Air can be blown from the outlet 19i to the vicinity of the ignition plug 16b to be cooled.

In this case, since the air guide portion 19g is cylindrical, air can be blown directly to the vicinity of the spark plug 16b from the outlet 19i without escape, so that the engine 16 is efficiently cooled. be able to.

Further, here, by reducing the opening area of the air outlet 19i from the opening area of the air inlet 19h, the wind speed near the air outlet 19i can be made higher than that near the air inlet 19h. Cooling can be performed efficiently even at times.

Incidentally, the test results show that the spark plug 1
6b had a seating temperature of about 250 ° C.
By introducing the wind in the vicinity of the spark plug 16b by 9g, the wind was reduced by about 10% to 15%.

The other configuration and operation are the same as those of the first embodiment, and the description is omitted.

The shape and the like of the air guide section are not limited to those of the above-described embodiment, and other shapes and the like may be used as long as the wind flowing outside the front fork can be guided to the vicinity of the ignition plug of the engine. The good thing is, of course.

In each of the above embodiments, the air guide portion is provided on the side of the leg shield on which the spark plug is provided. However, the present invention is not limited to this. Can also.

Furthermore, in each of the above embodiments, the engine is disposed horizontally, but the present invention is not limited to this, and the present invention can be applied to a vehicle in which the engine is mounted more vertically than the horizontal state.

[0036]

As described above, according to the invention described in each claim, the wind flowing outside the front fork is guided to the vicinity of the ignition plug of the engine by the wind guide portion provided on the leg shield. The engine cooling performance can be improved without increasing the number of parts.

According to the second aspect of the present invention, the cooling performance of the engine can be improved with a simple improvement by making the air guiding portion concave.

According to the third aspect of the present invention, the air guiding portion is formed in a duct shape, and the outlet of the duct is made closer to the vicinity of the ignition plug, so that there is no escape of the wind, and the engine is more effectively operated. Cooling near the spark plug.

According to the fourth aspect of the invention, since the opening area of the outlet is smaller than the opening area of the inlet, the wind speed near the outlet can be made faster than that near the inlet. Even when the vehicle speed is low, cooling can be performed efficiently.

[Brief description of the drawings]

FIG. 1 is a side view of a motorcycle according to a first embodiment of the present invention.

FIG. 2 is a front view of the motorcycle according to the first embodiment.

FIG. 3 is a schematic sectional view along a horizontal direction showing a main part of the present invention according to the first embodiment.

FIG. 4 is a side view of a motorcycle according to a second preferred embodiment of the present invention.

FIG. 5 is a front view of the motorcycle according to the second embodiment.

FIG. 6 is a schematic sectional view along a horizontal direction showing a main part of the present invention according to the second embodiment.

[Explanation of symbols]

 11 Body frame 14 Front fork 15 Front wheel 16 Engine 16a Cylinder head 16b Spark plug 19 Leg shield 19a Both sides 19c, 19g Wind guide 19d Inclined surface 19h Suction port 19i Air outlet

Claims (4)

[Claims] 1. A motorcycle provided with a leg shield covering a side of an engine, wherein a wind guide portion is formed at least on a side portion of the leg shield on which a spark plug of the engine is arranged, and The engine cooling wind introduction structure for a motorcycle, wherein a running wind flowing outside the front fork is guided to the vicinity of the spark plug at a portion. 2. The air guide section has a concave shape recessed toward the rear of the vehicle, and a bottom surface of the recess is formed as an inclined surface inclined toward the ignition plug, so that the front fork is formed on the inclined surface. The engine cooling air introduction structure for a motorcycle according to claim 1, wherein a running wind flowing further outside is guided to a vicinity of the ignition plug. 3. The air guide section has a duct shape, and introduces a traveling wind from a suction port formed at one end, and directs the traveling wind to a vicinity of the ignition plug from an outlet formed at the other end. The engine cooling air introduction structure for a motorcycle according to claim 1, wherein air can be blown toward the engine. 4. The engine cooling air introduction structure for a motorcycle according to claim 3, wherein an opening area of the outlet is smaller than an opening area of the inlet.