JPH0631061B2 - Vehicle intake system - Google Patents

Description

The present invention relates to an intake device for a vehicle such as a motorcycle or a tricycle.

(Problems to be Solved by the Related Art and Invention) A pair of left and right main pipes extending rearward from a head pipe are provided, a fuel tank is laid over the main pipes, and a plurality of cylinders are left and right from an engine case. In a vehicle with a multi-cylinder engine installed side by side underneath the main pipe, the width of the middle part between the main pipes on the left and right should be wide enough to correspond to the engine and left and right, and the rear part Has a narrow width.

On the other hand, a vehicle equipped with a multi-cylinder engine requires a large capacity air cleaner. When the air cleaner case (91) is simply formed in a rectangular shape as shown in FIG. In addition, on the left and right sides of the air inlet (93) side, there are places (95) and (95) where the air flow is stagnant and does not function effectively, and the volumetric efficiency cannot be improved.

Further, in order to improve the output of the engine, it is necessary to linearly extend the intake passage (air introduction pipe portion) of the square cylinder. However, in a parallel multi-cylinder engine in which the intake passage is arranged rearward, the flow of the intake passage cannot be sufficiently obtained because the intake passage covers the narrow seat. Or it is necessary to widen the width of the sheet.

If the intake passage is short, it is difficult to improve engine output,
Moreover, if the width of the seat is wide, the seat may not be comfortable to sit on.

The present invention has been devised in view of the above circumstances, and the object of the present invention is to effectively use the space between the left and right main pipes of a vehicle body frame equipped with a multi-cylinder engine,
An object of the present invention is to provide a vehicle device in which an air cleaner having a large capacity and excellent in volume efficiency can be arranged and an intake passage (air introduction pipe portion) can be sufficiently long.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention has a plurality of cylinders from an engine case, which are erected forward and upward, and from which cylinders an air introduction pipe portion including a carburetor is substantially above. Straight from the bottom of the air cleaner case, connect the air inlet part at the upper end of these air inlet pipes to the front part of the air cleaner case with a small vertical width, and store the air cleaner element in a place with a large vertical width of the air cleaner case. In addition, an air introducing pipe was connected, and this air introducing pipe was extended to the lower front part of the seat.

(Function) An air cleaner (51) with a large capacity can be installed according to the left and right width of the engine (27), and there is no place where the air flow is stagnant in the air cleaner case (55).
It is possible to increase the volumetric efficiency of.

A sufficient length can be secured by arranging the air introducing pipe (intake passage) linearly upward. By changing the width of the air cleaner case in the vertical direction and storing the air cleaner element in a large width area, a large element can be placed.

(Embodiment) A preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a side view of a motorcycle, FIG. 2 is a side sectional view of an essential part of an air cleaner portion, and FIG. 3 is a sectional plan view of the essential part.

(1) is a motorcycle, (3) is a handle, (5) is a front fork, (7) is a front wheel, (9) is a rear fork, (11) is a rear wheel,
The body frame (13) of the motorcycle (1) is the head pipe (15)
And the main pipe that extends rearward from the head pipe (15)
(17), a center pipe (19) extending downward from the rear wheel of the main pipe (17), a seat rail (21) extending rearward from an intermediate portion of the main pipe (17), and an upper portion of the center pipe (19). A rear stay (23) for connecting the seat rails (21) is provided.

The frame members (17), (19), (21) and (23) are provided in a pair on the left and right, and the main pipe (17) and the center pipe (19) are formed of a pipe material having a rectangular cross section.

The width between the left and right member pipes (17), (17) is the width (W ₁ ) between the middle parts (17a), (17a) in consideration of the layout of the vehicle body components.
Is set wide and the width (W ₂ ) between the rear parts (17b) and (17b) is set narrow.

A fuel tank (25) is laid over the main pipe (17),
A seat (26) is provided on the seat rail (21) to secure the fuel tank.
A recess (25a) is formed on the lower surface of (25).

The engine (27) is the main pipe (17), the center pipe
It is arranged below the main pipe (17) and in front of the center pipe (19) via (19), and drives the rear wheels (11) by engine power.

Engine (27) is a water-cooled four-cylinder engine, engine case
A cylinder head (31) and a head cover (33) are connected to the upper part of (29), and four cylinders (35) are vertically arranged side by side diagonally forward from the front of the engine case (29).

Above the cylinder head (31), four carburetors (37) are arranged side by side in a multi-row structure, and the air introduction part (41) above the case (39) of each carburetor (37) is arranged. ), An air inlet pipe (43) is projected obliquely upward, and a lead-out pipe is provided from the bottom of the case (39).
(45) are projected, and the outlet pipes (45) are respectively attached to the cylinder head (31).
In the figure, (47) is an exhaust pipe, and (49) is a radiator.

The air cleaner (51) is a space below the recessed portion (25a) of the fuel tank (25) and above the engine case (29), and the middle portion (17a), (17) of the left and right main pipes (17), (17). It is installed in the space between 17a) and the rear part (17b), (17b).

The air cleaner (51) consists of an air cleaner element (53) and an air cleaner case (55).
Is attached to the body frame (13) at an appropriate position.

The air cleaner case (55) includes an air introduction pipe (61), an upper case (63) connected to the air introduction pipe (61), and an upper case (6).
It consists of the lower case (65) that is connected to 3) and the above case (6).
3) and the width of the lower case (65) is the same as the main pipe (1
Corresponding to the widths (w ₁ ) and (W ₂ ) between 7) and (17), the rear width (W ₄ ) is made narrower than the front width (W ₃ ).

Air cleaner element (53) has upper and lower cases (63), (65)
An air inlet pipe that is located near the center of the vehicle width (C) and is connected to the air cleaner element (53) at the rear of the
(61) extends rearward along the center of the vehicle width (C) and forms an opening (61a) at the rear end facing rearward. In the embodiment, the opening (6
The battery box (66) was arranged facing the back of 1a).

The lower surface (65a) of the front part of the lower case (65) has the carburetor (3
7), located above the front part lower surface (65a) and facing the air introduction pipe parts (43), ...
Form (67).

Then, a laterally elongated concave case (77) consisting of a bottom surface portion (73) having four holes (71), ... and a side surface portion (75) erected from the outer edge of the bottom surface portion (73). Are provided, the holes (71), ... Are fitted to the air introduction pipe portions (43) of the carburetor (37), respectively, and the bottom surface is provided above the case of the carburetor (37) via the seal member (78). Department
(73) is placed, the upper end of the side surface (75) and the peripheral edge of the opening (67) are directly and detachably coupled via the seal member (79), and the air cleaner (51) and the carburetor (37) are attached. Connect.

The joint between the case (77) and the vaporizer (37) and the case (77)
As shown in Fig. 2, the joint between the air cleaner (51) and the air cleaner (51) is a place that is laterally covered by the left and right main pipes (17), (17) in consideration of the appearance. Division (4
Air funnels (81) were attached to 3) ,.

This embodiment is configured as described above, and the middle part (17a) to the rear part
Since the air cleaner (51) is arranged by effectively utilizing the space between the left and right main pipes (17), (17) across (17b), the air cleaner (51) with a large capacity corresponding to the left and right width of the engine (27) 51) can be provided.

In addition, the width of the air cleaner cases (63) and (65) is gradually reduced from the front to the rear, and the air introduction opening (61a) is provided on the rear side and the carburetor (37) is provided on the front side. Since the opening (67) for connection is provided, there is no place where the air flow is stagnant in the conventional air cleaner case, and therefore the air cleaner (51) having excellent volume efficiency can be arranged.

Further, since the air cleaner opening (61a) of the air cleaner (51) can be located at the center of the vehicle and behind the engine (27), the cool air can be smoothly sucked in without collecting the dynamic pressure. Air cleaner
(51) Water and the like can be efficiently prevented from entering the inside.

Further, in the embodiment, as shown in FIG. 3, carburetors (37 ₁ ), (37 ₂ ), (37 ₃ ), (37 ₄ ) arranged side by side are arranged in the order of ignition of each cylinder (35) ,. 37 ₁ ) → (37 ₃ ) → (37 ₄ ) → (37 ₂ ) → (37 ₃ ) →
That is, the carburetor (37 ₃ ) operates to the carburetor (37 ₄ ), the carburetor (37 ₂ ) to the carburetor (37 ₁ ), in order from the carburetor on the side of the vehicle width (C) to the outer carburetor. Since it was made to do so, a carburetor with a long distance from the air cleaner (51) to the air funnel (81)
The air supply to (37 ₄ ) and (37 ₁ ) is controlled by the short-distance vaporizer (37
₃ ), (37 ₂ ) using the air flow to each vaporizer (3
It is possible to uniformly and smoothly supply air to 7 ₁ ), (37 ₂ ), (37 ₃ ), and (37 ₄ ).

In the embodiment, the case of the three-cylinder engine (27) in which the cylinders are arranged side by side from the front of the engine case (29) has been described, but the number of cylinders is arbitrary and, for example, from the engine case (29). The present invention is also applied to a six-cylinder engine in which three cylinders are arranged on the left and right and the cylinders are erected in a V shape in a side view.
In short, the present invention is applied to a multi-cylinder engine having a plurality of cylinders arranged side by side.

Also, in the embodiment, the air cleaner case (55) and the carburetor (37)
Although the description has been given of the case where the connection is made via the case (77), such a connection method is optional, and for example, the connection part with the connecting tube may be provided side by side on the front part of the air cleaner case (55).

(Effect of the Invention) As is clear from the above description, according to the intake device of the present invention, the air introduction pipe portion (intake passage) is linearly erected substantially upward so that a sufficient length can be secured. Engine output can be improved. Therefore, it is not necessary to widen the width of the seat. Also, change the width of the air cleaner case up and down,
By accommodating a large air cleaner element in a location having a large width, a large capacity of the air cleaner can be secured, and an air cleaner excellent in volume efficiency can be arranged.

[Brief description of drawings]

FIG. 1 is a side view of a motorcycle, FIG. 2 is a side sectional view of an essential part of an air cleaner portion, and FIG. 3 is a sectional plan view of the essential part thereof.
The figure is a schematic plan view of a conventional air cleaner. In the drawing, (1) is a motorcycle, (15) is a head pipe, (17)
Is a main pipe, (17a) is an intermediate part, (17b) is a rear part, (25) is a heat tank, (26) is a seat, (27) is an engine, (29) is an engine case, (35) is a cylinder, (37) is a carburetor, (41) is an air introduction part, (42) is an intake introduction pipe part, (51) is an air cleaner, (5)
3) is an air cleaner element, and (55) is an air cleaner case.

Claims (1)

[Claims] 1. A pair of left and right main pipes extending rearward from a head pipe, wherein a width between the left and right main pipes is formed narrower between rear portions than between intermediate portions, and a fuel tank is provided on the main pipes. A seat is provided over the fuel tank, and the seat is provided behind the fuel tank. The space between the left and right main pipes between the middle portion and the rear portion is gradually reduced in the left-right width toward the rear and the vertical width. In a vehicle in which an air cleaner having an air cleaner case in which only the front part is made small is arranged, and a multi-cylinder engine in which a plurality of cylinders from the engine case are arranged side by side in a row below the air cleaner is provided. A plurality of cylinders from the above are erected forward and upward, and from these cylinders, an air introduction pipe section including a carburetor is linearly erected substantially upwards and The air introduction part at the upper end of the introduction pipe part is connected from below to the front part having a small vertical width of the air cleaner case, and the air cleaner element is housed and the air introduction pipe is connected to a large vertical width part of the air cleaner case. An air intake device for a vehicle, wherein the air introduction pipe is extended to a lower portion of a front portion of the seat.