JPH04292279A - Intake system in motor-scooter type vehicle - Google Patents

Abstract

PURPOSE:To provide such an intake system of a motor-scooter type vehicle that is able to take in air at a high position from the ground and, what is more, it can draw the relatively clean air. CONSTITUTION:A side frame 23 extending upward aslant in the rear from a floor part 14a is formed into a hollow form, and an air inlet port 30, leading to an inner hollow part, is installed in an upper part of the side frame, while a lower part of the side frame is connected to another air inlet port 32a of an air cleaner 32.

Description

[Detailed description of the invention] [Industrial application field]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake system for a scooter type vehicle.

0002

[Prior Art] Usually, a scooter type vehicle is equipped with a so-called power unit at the rear of the vehicle body, which integrates an engine, a rear wheel, and a power transmission means for connecting the two.
Clean air and fuel gas are supplied to the power unit in a mixed state from an air cleaner provided above. Outside air is sucked into this air cleaner through an air intake port provided directly on the air cleaner case or through a helmet box provided at the rear of the vehicle body (see Japanese Patent Laid-Open No. 1-136886). ).

0003

[Problems to be Solved by the Invention] However, in the above-mentioned conventional intake system for scooter type vehicles, the air intake port of the air cleaner is located at a low position on the vehicle body relatively close to the ground, which is disadvantageous against water etc. There is a side.

The present invention was made in view of the above circumstances, and allows air to be taken in at a high position from the ground.
It is an object of the present invention to provide an intake device for a scooter type vehicle that can inhale relatively clean air.

[0005]

[Means for Solving the Problems] In order to achieve the above object, in the present invention, a side frame extending rearward and diagonally upward from the floor portion is formed into a hollow shape, and an upper portion of the side frame is connected to an internal hollow portion. It is characterized by having an air inlet and connecting the lower part of the side frame to the air inlet of the air cleaner.

[0006]

[Operation] Since air is sucked in at the top of the side frame, air can be taken in at a position higher than the ground, allowing relatively clean air to be sucked in. Furthermore, since the originally existing side frame is used, compared to the case where a new dedicated member is used, less space is required for arranging the equipment, and the weight does not increase.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side view of a scooter type motorcycle to which the present invention is applied, and FIG. 2 is a plan view thereof. In Figure 1, reference numeral 1 denotes a body frame extending from the front of the vehicle body (left side in the figure) to the rear, 2 is a horizontal engine with cylinders extending to the front, and 3 is the engine 2 and rear wheels (drive wheels). The engine 2, the driving force transmitting device 3, and the rear wheels 4 constitute a power unit 5. This power unit 5 is connected to the vehicle body frame 1
It is connected to the rear part of the vehicle by a link mechanism 6 so as to be able to swing vertically, and is supported by the vehicle body frame 1 via a suspension 7.

Further, in FIG. 1, 9 is a handle, 10 is a front wheel having a tire 10b attached to a wheel 10a, 11 is a front fork attached to the vehicle body frame 1 and supports the front wheel 10, and 12 is a front end hinged. 13 is a storage case provided under the seat 12 for storing a helmet, etc. This storage case 16 is attached to brackets 23b and 23c attached to a side frame 23, which will be described later. The rear and rear parts are fixed with bolts and nuts, respectively. 1
4 is a fuel tank provided at the lower part of the floor part 14a at the center of the vehicle body, 15 is a vehicle body cover that covers the vehicle body frame 1 and the fuel tank, etc., 16 is a rear fender that covers the diagonally rear upper part of the rear wheel 4, 17 is a battery, and 18 is a oil tank, 19
is the exhaust pipe.

The vehicle body frame 2 includes a head pipe 21
A down tube 22 extends diagonally downward and rearward from the lower part of the head pipe 21 and has its lower end bent slightly backward, and is connected to a point raised slightly upward from the lower end of the down tube 22 and spreads left and right from there. The seat frame 23 includes a side frame 23 made of a pipe material that extends rearward in a substantially horizontal direction to the front portion of the seat, and after being bent, extends diagonally upward and rearward. The rear end of the side frame 23 is connected by front and rear brackets 23e and 23f,
A seat lock device 23ee is attached to the front bracket 23e.
is installed.

[0010] The side frame 23, as described later,
It functions as an air passageway that supplies cooling air to the engine 2 and also supplies air to the air cleaner case 32.

That is, an air intake port 22a is formed at the rear of the upper end of the down tube 22. A central portion of a cross pipe 24 is connected to the lower end of the down tube 22, and both ends of the cross pipe 24 extend diagonally upward to the left and right and are connected to the side frame 23.

Further, a cross pipe 25 having a U-shape when viewed from the front is connected to the rear end of the floor portion of the side frame 23, and a short connecting pipe 26 is attached to one side of the lower horizontal portion 25a of the cross pipe 25. ing. The connecting short pipe 26 is communicated with the inside of the bellcon case of the engine 2 via a duct 27.

On the other hand, a short connecting pipe 30 is attached to the approximately central portion of the rear inclined portion 23a of the side frame 23, and a connecting short pipe 30 is attached to the oblique front lower part of the place where the short connecting tube 30 is attached. A tube 31 is attached (see Figure 2). In addition, in FIG. 1, 35 is the vehicle body cover 1.
5 is an air intake port for the air cleaner case 32. As shown in FIGS. 3 to 6, at a position behind this air intake port 35 inside the vehicle body cover 15,
The tip of the duct 36 is fitted into the groove of the vehicle body cover 15, and the bolt 37 is inserted into the mounting portion 36d which bulges outward (see FIG. 6).

As shown in FIG. 3, the duct 36 has an air inlet 36a facing diagonally downward and forward, and an air outlet 36b facing diagonally rearward and downward.
The air passage 36c connecting the air inlet 36a and the air outlet 36b is connected to a baffle plate 3 with a dogleg-shaped cross section that is integrally formed inside the duct 36 and the outside plate of the duct 36.
8 to form a maze structure. The air outlet 36b is connected to the connecting short pipe 30 of the side frame 23. Note that a protrusion 39 is formed near the air inlet 36a of the duct 36 to prevent dust and rainwater from entering.

Further, one end of a flexible duct 41 is connected to the short connecting pipe 31 of the side frame 23 as shown in FIG. 7, and the other end of the flexible duct 41 is connected to the air suction port 32a of the air cleaner case 32. It is connected. As shown in FIGS. 8 and 9, the air cleaner case 32 has a fixed portion 32b provided at the bottom.
is fixed above the power transmission device 3 with bolts and attached to the vehicle body side. Air cleaner case 32
The air cleaner case body 43 has a structure divided into left and right parts, and is composed of an air cleaner case main body 43 located on the right side of the vehicle body and a lid member 44 located on the left side of the vehicle body. Lid member 44
is fixed to a boss 45 formed on the air cleaner case body 43 with a bolt 46. A cleaner element 47 is disposed between the air cleaner case body 43 and the lid member 44 and is held in a predetermined position by a stay 43a extending from the air cleaner case body 43. The front part of the air cleaner case body 43 is bulged out to the side so as to extend to the front of the rear wheel 4, and a rear fender 48 that covers the front of the rear wheel 4 is integrally formed there.

Air sent from the side frame 23 passes through a duct 41 to the air cleaner case 3.
2, from the dirty side formed inside the lid member 44 as shown by the arrow in the figure, through the cleaner element 47 to the clean side inside the air cleaner case body 43 (see FIG. 2), and from there to the duct. The fuel flows into the carburetor 50 via the fuel tank 49, where it is mixed with fuel and supplied to the engine 2. Note that the lid member 44 has an inner duct 44a built therein having an open end approximately in the center of the cleaner element 47, and is designed to allow air entering from the suction port 32a to reach the entire area of the cleaner element 47 as much as possible. There is. Furthermore, a recess 43b is formed on the side of the case body 43 to avoid interference with the rear suspension 7.

Next, the flow of air in the intake device of the scooter type motorcycle having the above structure will be explained. When a negative pressure is generated in the intake system by starting the engine 2, air is sucked in from the side opening 35 of the vehicle body cover 15 due to the negative pressure. This sucked air enters the duct 36, passes through an air passage 36c formed in a curved manner within the duct, and then connects to the top of the side frame 23 using a short connecting pipe 30.
Inflow through. The air then enters the air cleaner 32 via a flexible duct 41 that passes through the side frame 23 and extends rearward from the side frame 23 . Here, after being filtered, the clean air flows into the carburetor 50 through the duct 49, where it is mixed with fuel and further sent to the engine 2.

As described above, since the opening 35 of the vehicle body cover, which is an air intake port and which communicates with the air cleaner 32 through the side frame 23 and the like, is provided at a location high from the ground, sand, dirt, etc. It is difficult for dust or water to enter. Therefore, relatively clean air can be sucked in, and the maintenance period for the air cleaner 32 can be extended. Moreover, if we specifically look at the individual parts, we can see that the internal air passage 36c of the duct 36 is bent and has a labyrinth structure, and that the duct 36, the side frame 23, the flexible duct 41
, and the air passageway consisting of the air cleaner 32 has a labyrinth structure as a whole, so it can be said that the structure is difficult for dust, water, etc. to enter in these respects as well.

Furthermore, since the originally existing side frame 23 is used, compared to the case where a new dedicated member is used, less space is required for arranging the equipment, and the weight does not increase.

Although the air cleaner case 32 is provided above the power transmission device 3, in order to effectively utilize the empty space above the horizontally placed engine 2,
The front part of the air cleaner case body 43 bulges out laterally so as to extend in front of the rear wheel 4, and its capacity is set larger than that of the conventional case. As a result, the intake resistance is reduced and the output of the engine can be easily increased.

Furthermore, by bulging out the front part of the air cleaner case body 43 laterally, it can be interposed between the rear wheel 4 and the carburetor 50, and the mud thrown up by the rear wheel 4 can be removed. It is possible to prevent objects such as dirt and pebbles from hitting the carburetor 50 and the like.

In addition, when the engine 2 is driven and a fan attached to the crankshaft or the like rotates, the inside of the bellcon case becomes negative pressure due to the action of the fan. Along with this, air enters from the air intake port 22a at the rear of the upper end of the down tube 22, and the entered air flows through the down tube 22, the cross pipe 24, and the side frame 22.
3 floor section, cross pipe 25, and connecting short pipe 2
6 and is supplied into the shroud of the engine 2 to cool the inside of the bellcon case.

[0023] In this way, the air for engine cooling also
Since the air enters from the rear of the upper end of the down tube 22 which is located at a high position from the ground, it is difficult for sand, dust, or water to enter, similar to the air sucked into the air cleaner 32.

The present invention is not limited to motorcycles, but can be applied to tricycles and four-wheeled vehicles as long as they have a side frame extending obliquely upward and rearward from the center of the vehicle body.

[0025]

[Effects of the Invention] As explained above, according to the present invention, since air is sucked in at the upper part of the side frame, air can be taken in at a position higher than the ground, and relatively clean air can be sucked in. Furthermore, since the originally existing side frame is used, compared to the case where a new dedicated member is used, the device requires less space for arranging the equipment and does not increase the weight.

[Brief explanation of drawings]

FIG. 1 is an overall side view of a motorcycle to which the present invention is applied.

FIG. 2 is a plan view of the same.

FIG. 3 is a cross-sectional view of a duct connected to a side frame.

FIG. 4 is a side view of the duct.

FIG. 5 is a sectional view taken along line AA in FIG. 3;

FIG. 6 is a sectional view showing the mounting structure of the duct.

FIG. 7 is a side view of a duct connecting a side frame and an air cleaner.

FIG. 8 is a side view of the air cleaner.

FIG. 9 is a cross-sectional view of the air cleaner.

10 is a sectional view taken along line CC in FIG. 9. FIG.

[Explanation of symbols]

14a Floor part 22 Side frame 30 Side frame air suction port (short pipe for connection)
32 Air cleaner

Claims (1)

[Claims] Claim 1: A side frame extending rearward and diagonally upward from the floor part is formed into a hollow shape, and an air intake port communicating with the internal hollow part is provided in the upper part of the side frame, and an air cleaner is provided in the lower part of the side frame. An intake device for a scooter type vehicle, characterized in that it is connected to an air intake port.