JP2889592B2 - Motorcycle air intake system - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an intake device for supplying clean air filtered by an air cleaner to a motorcycle engine,
The air cleaner case, especially when a fuel supply device such as a carburetor or fuel injection device is connected to the front side of the engine
And improvement of the arrangement structure of elements.

[Conventional technology]

Some recent motorcycles have a so-called front intake and rear exhaust system in which a carburetor is connected to a front wall of an engine and an exhaust pipe is connected to a rear wall of the engine. This type of motorcycle has been developed for competitions that run at a high speed on a predetermined course.The intake device of this motorcycle for competition uses an air cleaner from the viewpoint of minimizing intake resistance and improving output. Is provided so that the outside air is directly sucked into the vaporizer (for example, Japanese Patent Application No. 62-168815).
No.).

[Problems to be solved by the invention]

By the way, in order to adopt the above-described front intake and rear exhaust systems to a commercially available motorcycle for driving on a public road, it is necessary to supply clean air filtered by an air cleaner to the engine from the viewpoint of ensuring durability of the engine. In this case, it is necessary to develop an appropriate intake device corresponding to a special structure in which the fuel supply device is connected to the front side of the engine. For example, depending on the arrangement structure of the air cleaner, the air cleaner capacity becomes insufficient, or even if the air cleaner capacity can be sufficiently secured, the air cleaner and the fuel supply device are separated,
There is a concern that the connecting duct connecting the two has a large diameter and is long, and it is difficult to secure an arrangement space for the connecting duct.

In view of the above circumstances, an object of the present invention is to provide an intake device for a motorcycle that can ensure a sufficient air cleaner capacity and does not cause a problem of a space for arranging a connection duct.

[Means for solving the problem]

The present invention relates to a motorcycle intake device for supplying clean air to an engine surrounded by a cowling, wherein an air filtration element is directly connected to a fuel supply device connected to the engine, and a partition is provided inside the cowling. Disposing a plate, bringing an outer peripheral edge of the partition plate into contact with an inner surface of the cowling via a seal member, and bringing an inner peripheral edge of the partition plate into contact with an outer surface of the engine via a seal member. The partition plate, a part of the cowling, and the engine form a substantially air-tight air cleaner case, the air cleaner case surrounds the fuel supply device and the element, and the outside air introduction duct is separated from the partition plate by the air cleaner. It is formed so as to protrude to the rear of the case, and an outside air inlet is The outside air inlet is provided so that the lower portion and both outer sides thereof are covered with the cowling, and is positioned so as to face the bottom surface of the crankcase at a position below the crankcase of the engine. .

Here, the air cleaner case of the present invention is not limited to the case where the air cleaner case is configured only with the cowling and the partition plate, but is provided with a cutout in a part of the partition plate, and the periphery of the cutout is in contact with the engine wall surface. That is, the case where the engine wall forms a part of the air cleaner case is also included.

Furthermore, the fuel supply device of the present invention includes both a normal carburetor and a fuel injection device in which a fuel injection valve and a throttle valve are arranged in a Venturi pipe.

[Action]

According to the intake device according to the present invention, the element is directly connected to the fuel supply device, and the periphery of the element is surrounded by the air cleaner case, so that the air cleaner and the fuel as in the case where the air cleaner is disposed apart from the carburetor are provided. A connecting duct to the supply device is not required, so that the above-described problems such as a space for arranging the connecting duct do not occur.

Further, the air cleaner case of the present invention includes an element,
Since it is composed of a part of the cowling located around the fuel supply device and a partition plate for partitioning between the inner surfaces of the cowling, an extremely large air cleaner capacity can be easily secured. Further, since the space around the element is used as the air cleaner, the space for arranging the air cleaner as in the related art is unnecessary, and the problem of the arranging space does not occur.

In addition, a partition plate is disposed in the cowling to form a substantially air-tight air cleaner case, and an outside air introduction duct is protruded from the partition plate to the rear of the air cleaner case. And since both outer sides are covered with the cowling and positioned so as to oppose the bottom surface of the crankcase at a position below the crankcase of the engine, muddy water and the like jumped up by the rear wheel may move the cowling and the partition plate. Even if it is transmitted, it will not be sucked into the air cleaner case,
Also, there is no dynamic pressure as in the case where the traveling wind is directly introduced, and there is no need to consider the effect of the dynamic pressure in the operation adjustment of the engine, so that the adjustment is easy and reliable.

Furthermore, not only the element but also the fuel supply device is surrounded by the substantially air-tight air cleaner case, so that muddy water and the like can be reliably prevented from being particularly applied to the operating portion of the fuel supply device.

〔Example〕

 Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 and FIG. 2 are views for explaining an intake system for a motorcycle according to an embodiment of the present invention.

In the drawing, reference numeral 1 denotes a motorcycle employing the apparatus of the embodiment, and a body frame 2 of the motorcycle extends left and right (hereinafter, referred to as front,
The rear, left and right are all facing the front of the vehicle.) Rear arm brackets 2c are provided at the rear ends of the pair of main frames 2b.
And both brackets 2c are connected to each other by a cross pipe. By the head pipe 2a, a front fork 4 that supports the front wheel 3 at its lower end is pivotally supported so as to be steerable left and right.
A right-division steering wheel 4a is fixed. The rear arm 6 that pivotally supports the rear wheel 5 at the rear end is pivotally supported by the rear arm bracket 2c so as to be vertically swingable.

A fuel tank 7 and a seat 8 are arranged in order from the front above the vehicle body frame 2. The left, right and rear sides of the seat 8 are side covers 9a, and the left, right and lower sides of the body frame 2 are under cowlings 9b.
Also, the front of the steering handle 4a is surrounded by an upper cowling 9c, and further above it is surrounded by a screen 9d,
Both the cover and the cowling are resin molded products.

An engine unit 10 is suspended and supported in the under cowling 9b. This engine unit 10 is of a water-cooled two-cycle parallel two-cylinder type. A cylinder body 12 and a cylinder head 13 are mounted on the front wall of a crankcase 11 integrated with a transmission case in a forwardly inclined state. The head bolt 14 fastens the crankcase 11.

A pair of left and right exhaust ports 12a, 12a are formed in the rear wall of the cylinder body 12, and the left and right exhaust ports 12a, 1a are formed.
The front ends of a pair of left and right exhaust pipes 15, 15 are connected to 2a. Each exhaust pipe 15 extends obliquely upward in a substantially straight line from the inside of the left and right main frames 2b to the rear end of the vehicle through the inside of the side cover 9a.

The left and right pistons 16 inserted and arranged in the respective cylinders of the cylinder body 12 are connected to left and right crank arms 17a of a crankshaft 17 provided at a front portion in the crankcase 11.
Are connected via connecting rods 18, respectively. Each of the crank arms 17a is connected to the crankcase 1 described above.
It is located in the left and right crank chambers 11a integrally formed in one.

In addition, intake openings 11b are formed in the front walls of the left and right crank chambers 11a, respectively, and the intake pipes 11c are integrally formed with the intake openings 11b so as to extend forward. A discharge port 20b, which is an opening on the downstream side of the vaporizer 20, is connected to each of the intake pipes 11c via a cab joint 19 made of hard rubber. Each of the vaporizers 20 is slightly raised, and an intake port 20a which is an upstream opening thereof.
The left and right common elements 21 for filtering air
Are directly connected.

The engine unit 10, the carburetor 20, and the element 21 are surrounded by the under cowling 9b.
The under cowling 9b is a U-shaped section viewed from the front and includes a front wall 23a, left and right walls 23b, and a bottom wall 23c. A partition plate is provided between the inner surface of each of these walls and the wall surface of the engine unit 10. 22 are interposed. This partition plate 22
Is in close contact with the inner surfaces of the walls 23a to 23c of the under cowling 9b via a sealing member 22a. A notch is formed in the partition plate 22 along the wall shape of the crankcase 11, the cylinder body 12, and the cylinder head 13 of the engine unit 10, and the periphery of the notch is in close contact with each wall via a seal member. Thus, an air cleaner case 25 that hermetically surrounds the vaporizer 20 and the element 21 is formed. In addition, the partition wall 22
The lower part of the crankcase 11 has an outside air introduction duct 22b
Is formed. The outside air introduction duct 22b extends rearward from the partition plate 22 and is bent upward so as to face the bottom surface of the crankcase 11. The cowling 9b is located below, on the left and right outside of the outside air introduction port 22c formed at the protruding end of the outside air introduction duct 22b.
The upper part of the outside air inlet 22c is covered by the bottom surface of the crankcase 11.

In addition, a radiator 24 is disposed above the air cleaner case 25 so as to straddle a space below the left and right main frames 2b. The radiator 24 has a core 24
a, and a head tank portion 24b connected to the left and right portions thereof, and a bracket 24c portion fixed to the head tank portion 24b is fixedly supported on the lower surface of the main frame 2b via a support bracket 28. ing.

 Next, the operation and effect of this embodiment will be described.

In the intake device of the present embodiment, the air sucked into the air cleaner case 25 from the outside air intake duct 22b is
After being filtered at 21, it is sucked into the vaporizer 20, where it is mixed with gasoline and sucked and supplied into the crank chamber 11a.

Since the element 21 is directly connected to the carburetor 20 and the periphery thereof is surrounded by the air cleaner case 25, clean air can be supplied to the carburetor 20 connected to the front side of the engine without any trouble. In this case, since the element 21 is directly connected to the carburetor 20, a connecting duct for connecting the air cleaner and the carburetor is not required, and the problem of securing an arrangement space for the connecting duct does not occur. By the way, following the air cleaner arrangement structure generally adopted in the case of the rear intake system,
When an air cleaner is placed inside the tank cover, the air cleaner capacity can be secured sufficiently, but the distance between the air cleaner and the carburetor is longer, and the connecting duct between the air cleaner and the carburetor is longer, which makes it difficult to secure the placement space. Although there is some concern, this embodiment does not have such a problem.

Also, by closing the space between the under cowling 9b and the engine wall with the partition plate 22, the air cleaner case 25 is configured.Therefore, it is not necessary to provide a special air cleaner case or secure a space for disposing the air cleaner case. The space around the element 21 can be directly used as an air cleaner case, and a sufficient capacity can be easily secured.

Further, the partition plate 22 is disposed in the cowling 9b to form a substantially air-tight air cleaner case 25, and the outside air introduction duct 22b is projected from the partition plate 22 to the rear of the air cleaner case 25, and the outside air formed at the projecting end is formed. Inlet
22c is positioned so that its lower side and both outer sides are covered with the cowling 9b and is located at a position below the crankcase 11 of the engine 10 so as to face the bottom surface of the crankcase 11, so that it is flipped up by the rear wheel. Even if muddy water or the like is transmitted through the cowling 9b or the partition plate 2, it is not sucked into the air cleaner case 25, and is not subjected to dynamic pressure as in a case where traveling wind is directly introduced. There is no need to consider the effect of dynamic pressure in the adjustment, so that the adjustment is easy and reliable.

Furthermore, since not only the element 21 but also the fuel supply device 20 is surrounded by the substantially air-tight air cleaner case 25, it is possible to reliably prevent muddy water or the like from splashing particularly on the operating portion of the fuel supply device 20.

Although a part of a cylinder, a crankcase, and the like was used as an air cleaner case as a wall of the engine, the air cleaner case of the present invention uses the inner peripheral edge of the partition plate as shown in a dashed line in FIG. By contacting the outer peripheral surface of the connecting portion with the air cleaner case, the connecting portion can also be used as a part of the air cleaner case.

〔The invention's effect〕

As described above, according to the motorcycle intake device according to the present invention, the element is directly connected to the fuel supply device, and the air cleaner case surrounding the element with the cowling and the partition wall is configured. This eliminates the need for a connecting duct for connecting the air cleaner and has the effect of ensuring a sufficient air cleaner capacity.

Further, the outside air introduction duct is projected from the partition plate to the rear of the air cleaner case, and the outside air introduction port formed at the projecting end is covered with the cowling below and outside of the outside air introduction port, and is positioned below the engine crankcase. At the bottom of the crankcase, muddy water splashed by the rear wheels will not be sucked into the air cleaner case, and the effect of dynamic pressure must be considered when adjusting the operation of the engine. The adjustment is easy and reliable.

[Brief description of the drawings]

FIGS. 1 and 2 are views for explaining a motorcycle intake device according to one embodiment of the present invention. FIG. 1 is a left side view of a motorcycle employing the present embodiment device. The figure is a front view thereof. In the figure, 1 is a motorcycle, 9b is an undercan ring, 10 is an engine, 15 is an exhaust pipe, 20 is a carburetor (fuel supply device), 21 is an element, 22 is a partition plate, and 25 is an air cleaner case.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B62M 7/02 B62M 39/00

Claims (1)

(57) [Claims] 1. An air intake system for a motorcycle for supplying clean air to an engine surrounded by a cowling, wherein an air filtering element is directly connected to a fuel supply device connected to the engine, and an air filtering element is provided inside the cowling. A partition plate is provided, an outer peripheral edge of the partition plate is brought into contact with an inner surface of the cowling via a seal member, and an inner peripheral edge of the partition plate is brought into contact with an outer surface of the engine via a seal member. Thereby, the partition plate, a part of the cowling, and the engine form a substantially sealed air cleaner case, the air cleaner case surrounds the fuel supply device and the element, and the outside air introduction duct is separated from the partition plate. It is formed so as to protrude backward from the air cleaner case and introduces outside air into the protruding end of the duct. Wherein the outside air introduction port is positioned so that its lower side and both outer sides are covered with the cowling, and is located below the crankcase of the engine and opposed to the bottom surface of the crankcase. Motorcycle air intake system.