JP3336583B2 - Inlet intake device for motorcycles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake air introduction structure for a motorcycle in which an intake system member such as an air cleaner is disposed so as to be wrapped under a fuel tank.

[0002]

2. Description of the Related Art As a conventional intake introduction structure for a motorcycle of this type, there are a conventional intake introduction structure in which outside air passes through a pipe penetrating a fuel tank and is introduced into an air cleaner below the fuel tank, and a front end of the fuel tank. A tank cover that is continuous on the same surface in the portion, an air cleaner is provided in the tank cover, and outside air is introduced into the tank cover by an introduction pipe (for example, JP-A-2-128977). It has been known.

[0003]

By the way, of the above-mentioned conventional examples, in a type in which a pipe is passed through a fuel tank,
There was a problem that the structure of the tank became complicated and the cost increased. In addition, in the case where the air cleaner is provided inside the tank cover at the front end of the fuel tank, it is difficult to secure sufficient capacity of the fuel tank.
It has been desired to secure an air passage that does not sacrifice the capacity of the air passage. Ma
In addition, the influence of intake by dynamic pressure is reduced, and intake efficiency is improved.
It is also desired to improve.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a motorcycle air intake system according to the present invention has a fuel tank disposed above an engine disposed substantially at the center of a vehicle body. In a configuration in which the intake system member of the engine is disposed in a concave portion provided on the lower surface of the tank, the front and side surfaces of the intake system member are covered with a main body of the fuel tank,
The outside of a portion of the fuel tank covering the intake system member is covered with a tank cover having a predetermined distance from the outer surface of the fuel tank.
A gap is formed from above to below the outer surface of the fuel tank.
Air passage opening downward, and
The upper end of the cover is connected to an inlet pipe with one end connected,
The introduction pipe leads from the front of the vehicle body to the upper part of the air passage.
The introduced outside air flows down the air passage, and
In the recess provided on the lower surface of the fuel tank from the lower end of the bar
Is introduced into the intake system member . This and
End of the tank cover overlapping the fuel tank
Contacting the outer surface of the fuel tank with a continuous surface,
The rear portion of the air passage may be configured to close. The method according to claim 1 or 2, wherein the air is guided through the air passage.
A gas guide for introducing the outside air to the intake section of the intake system member.
An id plate can also be provided. Further, claims 1 to 3
In any one of the above, the air vent is connected to the outside of the fuel tank.
It can also be formed from the front to the side of the surface.

[0005]

[Action] The outside air introduced from the front of the vehicle body by the introduction pipe is
One end of the inlet pipe enters the tank cover and enters the gap between the tank cover and the fuel tank . This gap is the fuel tank
Formed from the front to the side of the outer surface and opens downward
Outside air flows downward through this air passage . When the outside air reaches the lower surface of the fuel tank in which the concave portion is formed in advance, it is introduced into an intake system member provided in the concave portion, and is further taken into the engine located below the intake system member from the intake system member. . At this time, the outside air does not directly enter the intake system member, but from the upper side outside the fuel tank to the lower side.
The air flows from the top to the bottom in the air passage formed to reach the intake member through the outside of the fuel tank.
Therefore, the influence of the dynamic pressure on the intake system member is reduced. Ma
The end of the tank cover overlapping the fuel tank is
So that it contacts the outer surface of the fuel tank with a continuous surface
This closes the rear of the air passage at this end,
The outside air introduced into the air passage from the
Flow downward, improving the intake efficiency of the intake member
Let it. Furthermore, it absorbs outside air introduced through the air passage.
If a guide plate for guiding the air system to the intake section is provided,
The air intake efficiency of the air member is further improved. Also, the air passage
If it is formed from the front to the side of the outer surface of the fuel tank,
The cross-sectional area of the air passage can be increased, and the lower opening surface
As the volume increases, the recess formed in the lower part of the fuel tank
The intake efficiency of the intake system member disposed therein is improved .

[0006]

According to the present invention, there is provided an engine disposed substantially at the center of a vehicle body, a fuel tank disposed above the engine, and a recess provided on a lower surface of the fuel tank. The intake system members of the engine covered by the main body of the fuel tank, and the outside of the portion covering the intake system members of the fuel tank,
A tank cover covering with an outer surface with a predetermined distance in the fuel tank is provided under the gap from above the fuel tank outer surface
Air passage that is formed in
With one end connected to the top of the tank cover in the air passage
The inlet pipe is communicated, and the inlet pipe is used to
Outside air introduced into the upper part of the air passage flows down the air passage
From the lower end of the tank cover under the fuel tank.
It was introduced into the intake system member in the recess provided on the surface .

Therefore, a pipe which penetrates the fuel tank as in the related art is not required, and the same component structure as that of a normal fuel tank may be used, thereby avoiding an increase in cost. In addition, the inside of the tank cover can be used as the volume of the fuel tank, without having to sacrifice the capacity of the fuel tank as in the prior art. Furthermore, outside air does not directly enter the intake system members, but rises through the air passage formed on the outer surface of the fuel tank.
Flows downward from the fuel tank and wraps around the outside of the fuel tank, so that the influence of dynamic pressure can be reduced and external air can be taken in. In addition, the tank cover may be loaded onto the fuel tank.
End is connected to the outer surface of the fuel tank in a continuous plane.
To close the rear of the air passage at this end
As a result, outside air introduced into the air passage from above escapes backward.
The air flows efficiently downward without any
Efficiency can be improved. In addition, through the air passage
To guide the outside air introduced into the intake section of the intake system
If a guide plate is provided, the intake of outside air into the intake section is further improved
It is possible to improve the intake efficiency of the intake member
be able to. Also, place the air passage in front of the outer surface of the fuel tank.
If it is formed from the side to the side, the passage cross-sectional area of the air passage
Can be increased, and the opening area at the bottom also increases.
Intake system arranged in a recess formed in the lower part of the fuel tank
The intake efficiency of the member can be improved.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment will be described with reference to FIGS. FIG. 1 is a sectional view taken along the line AA of FIG.
FIG. 2 is a schematic cross-sectional view taken along a line, FIG. 2 is an external side view of a motorcycle to which the present embodiment is applied, FIG. 3 is a plan view of a main part of a front part of the motorcycle, and FIG. It is a partial notch side view of the principal part used as a center.

First, in FIG. 2, a main frame 2 extending rearward in a pair from left to right from a head pipe 1 at a front end.
, A V-type engine 3 is supported substantially at the center of the vehicle body, and an air cleaner 5 is connected upstream of a carburetor 4 attached to an intake port of the engine 3.

The air cleaner 5 is an example of an intake system member in the present application, and is disposed in a space defined by a concave portion 7 (see FIG. 4) provided below a front end of a fuel tank 6 supported on the main frame 2. The front and sides of the fuel tank 5 are covered by a main body of the fuel tank 6 and are wrapped under the fuel tank 6.

Further, the outside of the portion that covers the air cleaner 5 at the front of the fuel tank 6 is covered from the front to the side by the tank cover 8, and the upper right and left sides of the tank cover 8, as apparent from FIG. A pair of left and right inlet pipes 10
Are connected so as to communicate with the inner space of the tank cover 8, and the front end 12 of the introduction pipe 10 is connected to the outside air introduction port 14 inside the fairing 13.

The outside air introduction port 14 opens forward to the front left and right of the fairing 13, and an outside air introduction recess 15 reaching the outside air introduction port 14 is formed on the front left and right surfaces of the fairing 13 in front of the outside air introduction port 14. A rearview mirror 16 is attached to the upper side surface of the fairing 13 (FIG. 2).

As shown in FIGS. 1, 3 and 4, from the front end of the bottom case 20 of the air cleaner 5 housed in the space between the left and right main frames 2, 2 toward the lower end of the head pipe 1, The lower guide plate 21 is integrally formed to extend forward.

An intake duct 23 is integrally formed at the front end of the case cover 22 so as to extend forward into the space between the left and right main frames 2 and 2. It opens downward above 21. Note that an air filter 24 is provided in the case cover 22.

Further, an upper guide plate 25 is provided above the intake duct 23 and extends downward from the front end of the recess 7. The tip of the upper guide plate 25 extends downward toward the upper rear position of the head pipe 1 in the space between the left and right main frames 2, 2.

Therefore, the opening at the tip of the intake duct 23 is
It is located in a space surrounded by the head pipe 1, the left and right main frames 2, the lower guide plate 21, and the upper guide plate 25, and outside air is introduced into the air cleaner 5 from this space.

The lower end of the tank cover 8 is close to the upper end surface of the main frame 2, and the gap between the tank cover 8 and the main frame 2 is sealed by a seal rubber 26, as shown in FIG. A predetermined gap 27 is formed between the inner surface of the tank cover 8 and the front end of the fuel tank 6 covered by the tank cover 8. The size of the gap 27 is set in advance according to appropriate conditions so that a necessary ventilation cross-sectional area is obtained.

An opening 29 is formed on the upper surface of the tank cover 8 and is surrounded by a flange 28 projecting upward. The rear end 11 of the introduction pipe 10 is fitted into the flange 28. The opening 29 is located above the upper surface of the fuel tank 6 at an appropriate interval. Therefore, the introduction pipe 1 is provided through the opening 29 and the gap 27 of the tank cover 8.
0 communicates with the opening at the tip end of the intake duct 23. As is apparent from FIG. 1, the gap 27 forms an air passage which is a passage for outside air . Note that the intake duct 23
It is an example of the suction part in the invention. This air passage
Of the outer surface of the fuel tank 6 from above and below and from the front
It is formed to the side and opens downward, and this air passage
An introduction pipe 10 communicates with the upper part, and the introduction pipe 10
The outside air introduced into the upper part of the air passage from the front of the body
To the bottom of the tank cover 8
Take out from the lower opening of the road and install it on the lower surface of the front end of the fuel tank 6.
To be introduced into the air cleaner 5 in the recess 7 formed.
ing. Further, as shown in FIG.
The end overlapping fuel tank 6 is connected to the outer surface of fuel tank 6.
Being in contact with each other, the rear of the air passage in the longitudinal direction of the vehicle
The part is closed.

The lower surface portion of the introduction pipe 10 in front of the middle portion is
A mounting seat 31 for the rearview mirror 16 is provided along a curved edge 30 of the fairing 13 in a side view (FIG. 4) and at a side position of the fairing 13 overlapping the introduction tube 10 in a side view.
Is provided.

As shown in FIG. 3, a relief portion 32 is formed on the outer side surface of the introduction pipe 10 near the mounting seat 31 so as to be recessed so as to be narrower. In FIG. 3, reference numeral 33 denotes a handle, 34 denotes a top bridge, and 35 denotes an instrument panel.

As is apparent from FIG.
Covers the front part of the vehicle body from the front to the left and right sides including the side of the engine 3, and a headlight 36 is attached to the front end.

Further, above and below the engine 3 inside the fairing 13, a separate radiator 37 is provided.
A, 37B and a front portion of an exhaust pipe 38 extending from the front bank side of the engine 3 are provided.

An exhaust pipe 39 extending from the rear of the exhaust pipe 38 and the rear bank of the engine 3 is provided with a cantilevered rear arm 40.
, And extends to the left side of the vehicle body, and extends obliquely upward and rearward while crossing the outside of the rear arm 40.

In FIG. 2, reference numeral 41 denotes a bottom bridge, 42 denotes an inverted front fork, 43 denotes a front wheel, and 44 denotes a front wheel.
Is a seat, 45 is a rear cover, and 46 is a rear wheel.

Next, the operation of this embodiment will be described. First,
In FIG. 4, the outside air introduced from the outside air introduction port 14 passes through the introduction pipe 10 and enters the tank cover 8 through the opening 29. Further, a gap 27 is provided between the tank cover 8 and the fuel tank 6 at a predetermined interval. As shown in FIG. 1, the air enters the space between the left and right main frames 2, 2 through the gap 27.

Here, the outside air enters the intake duct 23 from between the lower guide plate 21 and the upper guide plate 25, further enters the case cover 22, is purified by the air filter 24, and then vaporizes from the bottom case 20. The gas is introduced into the intake port of the engine 3 through the inside of the vessel 4.

At this time, the outside air passes through the gap 27 outside the fuel tank.
As an air passage opening downward in front of and on the side of the surface
Since it passes from above to below , the introduction pipe 10
Troublesome work of vertically penetrating through the front of the fuel tank 6 can be eliminated. That is, the gap 27 can be easily formed by covering the fuel tank 6 with the tank cover 8, and the gap can be adjusted relatively freely.

In addition, since it is not necessary to dispose the air cleaner 5 in front of the fuel tank 6, there is no need to cut off the front part of the fuel tank 6 as in the conventional case, and the capacity of the fuel tank 6 is sacrificed. Instead, the front portion of the fuel tank 6 is extended to the front so as to cover the air cleaner 5 and a sufficient capacity can be secured. In addition, the air passage is cut off
The area can be increased, and the opening area at the bottom also increases.
And is disposed in the recess 7 formed in the lower part of the fuel tank.
The intake efficiency of the air cleaner 5 is improved .

Further, the outside air does not directly enter the air cleaner 5, but the outside of the fuel tank extends downward from above.
Since the air flows from the top to the bottom in the air passage formed so as to go around the outside of the fuel tank 6 , the influence of the dynamic pressure can be reduced and the outside air can be taken in. Moreover,
One end to the upper part of the tank cover 8 in the air passage which is the gap 27
Is connected to the introduction pipe 11 to which the
Outside air introduced into the upper part of the air passage from the front of the vehicle
To the bottom of the air passage and out of the opening,
8 from the lower end of the recess 7 provided on the lower surface of the fuel tank 6.
Introduced to air cleaner 5 to improve intake efficiency of intake members
Can be up. The fuel tank of the tank cover 8
Connect the end that overlaps the ink tank 6 to the outer surface of the fuel tank.
At the end of the air passage at this end.
Can be closed and the outside introduced into the air passage from above
Chi will flow efficiently downward without falling backwards,
The intake efficiency of the air cleaner 5 can be further improved.
You.

Further, since the intake duct 23 is projected into a relatively large space formed between the left and right main frames 2, 2, the degree of freedom in providing the intake duct 23 is increased. In addition, the lower guide plate 21 and the upper guide plate 2
5, the air passage to the intake duct 23 is
Can outside air uptake introduced through more securely, further
Can improve the air intake efficiency of the air cleaner 5
You.

The present invention is not limited to the above embodiment, but can be applied in various ways. For example, in a vehicle without an air cleaner, the intake system member of the present invention is a carburetor or the like. You may.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a main part of an embodiment.

FIG. 2 is a side view of a motorcycle to which the intake device of the embodiment is applied.

FIG. 3 is a plan view of a main part of a front portion of the vehicle body according to the embodiment.

FIG. 4 is a cutaway side view of a main part according to the embodiment.

[Explanation of symbols]

2: Main frame, 3: Engine, 4: Vaporizer, 5:
Air cleaner, 6: fuel tank, 7: recess, 8: tank cover, 10: introduction pipe, 13: fairing, 14:
Inlet, 23: suction duct, 27: gap

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B62J 39/00

Claims (4)

(57) [Claims] 1. An engine according to claim 1, wherein a fuel tank is disposed above an engine disposed substantially at the center of the vehicle body, and an intake system member of the engine is disposed in a recess provided on a lower surface of the fuel tank. The front and sides of the fuel tank are covered with the main body of the fuel tank, and the outside of the portion of the fuel tank that covers the intake system member is covered with a tank cover provided with a predetermined distance from the outer surface of the fuel tank. From above to below the surface
Air passage that opens downward toward the
Line to the top of the tank cover.
Through the air passage from the front of the vehicle body
The outside air introduced into the upper part flows downward, and
From the lower opening of the tank cover and from the lower end of the tank cover.
An intake introduction device for a motorcycle, wherein the intake introduction device is introduced into the intake system member in a concave portion provided on a lower surface of a fuel tank . 2. The weight of the tank cover against the fuel tank
Is connected to the outer surface of the fuel tank in a continuous plane.
And the rear part of the air passage is closed.
The air intake introduction device for a motorcycle according to claim 1. 3. A gap between the tank cover and the fuel tank is provided.
Guides outside air introduced through to the intake section of the intake system member
A guide plate for providing
2. The motorcycle air intake device according to 2. 4. The fuel tank according to claim 1, wherein the air passage is provided on an outer surface of the fuel tank.
Characterized by being formed from the front to the side of the
Intake intake for a motorcycle according to any one of claims 1 to 3.
apparatus.