JP3430596B2 - Motorcycle engine intake system - 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 system for a motorcycle engine.

[0002]

2. Description of the Related Art An engine of a motorcycle is supplied with air purified by filtering dust with an air cleaner. By the way, since the air cleaner is usually installed in the rear or upper part of the engine, the air cleaner tends to inhale the air heated by the engine that emits high heat. In this case, the air expands with increasing temperature and becomes less dense, so the intake efficiency of the engine deteriorates,
The output also decreases.

As an example for solving the above problem, there is one in which an opening is formed in a fairing which covers the front surface of a motorcycle, and an intake duct which is directly connected to an intake port of an air cleaner is connected to this opening.

With this structure, fresh air from the front of the vehicle, which has not been heated by the engine, flows into the air cleaner, so that the above problem is solved. However, since a hole for introducing fresh air is provided in the fairing or an intake duct is required, there is a problem that it takes much time to assemble.

Further, in order to keep the efficiency of filling fresh air into the engine high, it is necessary to further lower a little ventilation resistance caused by filtration of the air cleaner. On the other hand, intake noise is generated by the pulsation of intake of air into the engine.
In order to reduce this intake noise, it is necessary to smooth the flow of air introduced into the engine. For that purpose, it is desirable that the capacity of the air cleaner is as large as possible.

FIG. 5 shows an example of the prior art, which is an example of a structure in which the capacity of the air cleaner is increased (see Japanese Patent Publication No. 3-22353). In FIG. 5, the air cleaner structure a has a structure in which an intake box c is connected to an air cleaner b via a connecting tool d, and the air cleaner is substantially divided into two parts to increase the capacity of the air cleaner. In the air cleaner b, a cleaner element e is arranged substantially in the center of the cleaner case f so as to be parallel to the upper and lower surfaces f ′ of the cleaner case f.

However, in such an air cleaner structure a, in order to replace the cleaner element e, the air cleaner b and the intake box c are first disconnected, and then the cleaner element e is removed from the air cleaner b. There was a problem that had to be.

Further, in general, the air cleaner is designed to supply fresh air to the engine through the carburetor, and the carburetor is provided with a wire for operating its throttle valve. This wire is connected to the throttle grip of the steering wheel so that the rider can operate the throttle valve. However, in the air cleaner structure a,
There is a problem that the connecting tool d between the air cleaner b and the intake box c interferes with the work of connecting the wire.

[0009]

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problems. The problem is not only to supply fresh air to an air cleaner sufficiently without requiring at least an intake duct, but also to provide a cleaner element. It is an object of the present invention to provide an intake system for an engine for a motorcycle, which can be easily replaced and can be easily connected to a wire connecting a throttle grip and a throttle valve.

[0010]

An intake system for a motorcycle engine according to claim 1 is arranged in a space partitioned by the engine, a gasoline tank, and a head pipe and sucks in fresh air. And a first cleaner chamber into which the fresh air is introduced for the first time, and the fresh air from the first cleaner chamber is connected to the first cleaner chamber. An intake system for a motorcycle engine, comprising: a second cleaner chamber that is transferred and introduces this fresh air into the engine through a carburetor; and a cleaner element that is arranged at a connecting portion between these two cleaner chambers. , A plurality of the fresh air inlets are provided so as to be connected to openings formed on the left and right sides of the fairing that covers the front surface of the vehicle, and the second cleaner chamber collects fresh air from the first cleaner chamber. An introduction part of a bifurcated branch that leads to the downstream side of the second cleaner chamber, and a main chamber located on the downstream side where fresh air from the first cleaner chamber introduced by this introduction part is gathered, It is characterized in that the introduction portion of the bifurcated branch is formed in a tapered shape toward the downstream side.

An intake system for a motorcycle engine according to a second aspect is arranged in a space partitioned by the engine, a gasoline tank and a head pipe, and is a fresh air intake port for taking in fresh air. Is directed to the front of the vehicle and the fresh air is introduced first, and the fresh air is connected to the first cleaner chamber to transfer the fresh air from the first cleaner chamber and A second cleaner chamber that introduces air into the engine through a carburetor, and an intake device for a motorcycle engine that includes a cleaner element that is arranged at a connecting portion between these two cleaner chambers,
The fresh air intake port is provided in the lower part of the head pipe of the vehicle and in the front center of the lower surface of the first cleaner chamber, and the second cleaner chamber receives the fresh air from the first cleaner chamber by the second cleaner chamber. Of the bifurcated branch leading to the downstream side of the, and a main chamber located on the downstream side where the fresh air introduced from the first cleaner chamber introduced by the introduced section gathers, and the bifurcated branch is introduced. It is characterized in that the portion is formed in a tapered shape toward the downstream side.

[0012]

Therefore, according to the intake system for a motorcycle engine according to claim 1 of the present invention, the fresh air intake port itself of the intake system for the motorcycle engine is directed toward the front of the vehicle. It comes into the intake device directly. Therefore, the opening to the fairing and the suction duct, which are required in the conventional technology, are not required. Further, since the cleaner element is arranged at the connecting portion between the first cleaner chamber and the second cleaner chamber, when replacing the cleaner element, disconnect the first cleaner chamber and the second cleaner chamber. The cleaner element can be taken out by itself.

According to the second aspect of the present invention, the intake system for a motorcycle engine allows fresh air from the first cleaner chamber to pass through the introduction portion of the second cleaner chamber to the second cleaner. Since it is introduced into the main chamber of the chamber, the introduction part substantially corresponds to the connecting tool d for connecting the air cleaner b and the intake box c described in the section of the prior art, but the introduction part is bifurcated. Because of the branched and separated form, the introduction portion does not interfere with the work of connecting the wire connecting the throttle grip and the throttle valve.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An intake system 1 for a motorcycle engine according to the present invention will be described in detail below with reference to the accompanying drawings. 1 is a side view showing a state in which an intake device is attached to a vehicle body frame with a part thereof omitted, FIG. 2 is a plan view of FIG. 1, FIG. 3 shows a modified example corresponding to FIG. 1, and FIG.
FIG. 4 is a plan view of FIG. 3.

As shown in FIG. 1, the main frame 2 is connected to a head pipe 4 which supports a steering shaft 3 at its front portion, and extends rearward from the head pipe 4 with a space left and right from the body. There is. An engine 6 is attached below the main frame 2 by an appropriate fixing means, and a gasoline tank 8 is placed above the main frame 2.

The engine 6 and the gasoline tank 8
The air intake device 1 is arranged in the space 10 defined by the space around the head pipe. Here, around the head pipe means the head pipe 4 itself or /
Also, it refers to a part (not shown) located in the vicinity of the head pipe 4 as a center.

The intake device 1 is a tubular body through which fresh air flows, and a fresh air suction port 12a for sucking fresh air is directed toward the front of the vehicle to introduce the fresh air first. A chamber 12 and a second cleaner chamber 16 that is connected to the first cleaner chamber 12 to transfer the fresh air from the first cleaner chamber 12 and to introduce the fresh air into the engine 6 via the carburetor 14. , These first cleaner chambers 12
And a rectangular cleaner element 20 arranged in a connecting portion 18 between the second cleaner chamber 16 and the second cleaner chamber 16.

As shown in the drawing, the first cleaner chamber 12 has a shape such as a helmet with a hoe in plan view. More specifically, the introduction pipes 24.2 are connected to the openings 22a, 22a formed on the left and right sides of the fairing 22, which covers the front surface of the motorcycle 20, and have the fresh air intake ports 12a, respectively.
4 and a main chamber 26 in which fresh air from the introducing pipes 24 and 24 gather and which has a rectangular opening 26a at the rear.

The second cleaner chamber 16 introduces the fresh air from the first cleaner chamber 12 to the downstream side of the second cleaner chamber 16 by means of a bifurcated branch 28, and the first introduced by the introduction part 28. The main chamber 30 is located on the downstream side where fresh air from one cleaner chamber 12 gathers.

The lead-in portion 28 is spaced apart in the vehicle side direction and is tapered rearwardly to form leg portions 28a, 28a.
And a body portion 28b having a rectangular opening 28b 'at the front and connecting the leg portions 28a, 28a at their front ends. An annular groove 2 for connecting the introduction portion 28 to the main chamber 30 is provided on the outer peripheral surface of the legs 28a, 28a on the rear end side.
8a ₁ and 28a ₁ are formed (see FIG. 1).

The main chamber 26 of the first cleaner chamber 12
The rectangular opening 26a of the second cleaning chamber 16 and the rectangular opening 28b 'of the second cleaner chamber 16 are fitted to each other, and the fitting forms the connecting portion 18, so that the cleaner element 20 arranged therein is The position is held by an appropriate fixing means.

A connection pipe 32 connected to the carburetor 14 is attached to the main chamber 30, and the connection pipe 32 has a connection hole 34 formed in the main chamber 30.
An annular groove 32a is formed for connecting to. A blow-by gas pipe 36 that connects the main chamber 30 and the inside of the cylinder head 6a of the engine 6 is provided near the connection hole 34. The reference numeral 38 indicates a radiator located in front of the engine 6.

FIGS. 3 and 4 show a modified example 1A of the intake system 1 for a motorcycle engine, which is different from the intake system 1 for the motorcycle engine in that the introduction pipe is the same. The only difference is that an introduction pipe 38 is provided instead of 24. The introduction pipe 38 is provided in the main chamber 26 so that the intake port 38a is located at the lower rear of the head pipe 4.
Is formed in the center of the lower surface of the front. Introductory pipe 3
8 eliminates the need to provide the openings 22a, 22a in the fairing 22 and can be applied to a motorcycle without a fairing.

According to the intake system 1 for the motorcycle engine, however, the fresh air directly enters the intake system 1 because the fresh air intake port 12a itself is directed toward the front of the vehicle. For this reason, at least the suction duct required in the prior art becomes unnecessary. Further, since the cleaner element 20 is arranged at the connecting portion 18 between the first cleaner chamber 12 and the second cleaner chamber 16, when the cleaner element 20 is replaced, the first cleaner chamber 12 and the second cleaner chamber 12 are replaced. The cleaner element 20 can be taken out only by disconnecting the connection with the chamber 16. Therefore, replacement of the cleaner element can be facilitated.

According to the intake system 1 for a motorcycle engine according to claim 2 of the present invention, the fresh air from the first cleaner chamber 12 passes through the introduction portion 28 of the second cleaner chamber 16. Since it is introduced into the main chamber 30 of the second cleaner chamber 16, the introducing portion 28 substantially corresponds to the connector d that connects the air cleaner b and the intake box c described in the section of the prior art. Since the introduction portion 28 is in a bifurcated and separated form, the introduction portion 28 does not interfere with connection work of a wire (not shown) that connects the throttle grip and the throttle valve. Therefore, the work of connecting the wire can be easily performed.

[0026]

According to the intake system for a motorcycle engine of the present invention, fresh air can be sufficiently supplied to the air cleaner without requiring at least an intake duct, and the cleaner element can be replaced easily. Further, the work of connecting the wire connecting the throttle grip and the throttle valve can be easily performed.

[Brief description of drawings]

FIG. 1 is a side view showing a state in which an intake device is attached to a vehicle body frame with a part thereof omitted.

FIG. 2 is a plan view of FIG.

FIG. 3 is a diagram showing a modified example and corresponding to FIG. 1.

FIG. 4 is a plan view of FIG.

FIG. 5 is a diagram showing a conventional technique.

[Explanation of symbols]

1 Intake device for motorcycle engine 4 head pipe 6 engine 8 petrol tanks 10 spaces 12 First cleaner room 12a Fresh air inlet 14 carburetor 16 Second cleaner room 18 Connected part 20 cleaner element 28 Introduction 30 main rooms

Continuation of the front page (56) References JP-A-64-53055 (JP, A) JP-A-59-40947 (JP, A) Actually open 1-87096 (JP, U) Actually open 56-48980 (JP , U) (58) Fields investigated (Int.Cl. ⁷ , DB name) F02M 35/14-35/16 F02M 35/024 B62K 11/00

Claims (2)

(57) [Claims] 1. A fresh air intake port, which is arranged in a space partitioned by an engine, a gasoline tank, and a head pipe, is provided for sucking fresh air, and the fresh air is first directed toward the front of the vehicle. A first cleaner chamber to be introduced, and a second air which is connected to the first cleaner chamber to transfer the fresh air from the first cleaner chamber and introduces the fresh air into the engine through a carburetor. and a cleaner chamber, met intake system for motorcycle engines with cleaner element disposed in connection portions of both the cleaner chamber
The fresh air intake port covers the front of the vehicle on either side of the fairing.
A plurality is provided so as to be connected to the openings formed on both sides,
The second cleaner room is the fresh air from the first cleaner room.
Introducing part of bifurcated branch leading to the downstream side of the second cleaner chamber
And the first cleaner introduced by this introduction part
The main room is located on the downstream side where fresh air from the room gathers.
And the introduction part of the bifurcated branch tapers toward the downstream side.
An intake device for a motorcycle engine, which is formed into a shape . 2. An engine, a gasoline tank, and a head
It is placed in a space that is divided by the pipe and the surroundings, and fresh air
The fresh air intake port for inhaling is directed toward the front of the vehicle
The first cleaner chamber where Qi is introduced first, and this first
The fresh air is connected to the cleaner chamber and the fresh air is supplied to the first cleaner.
This new energy is transferred from the room through the carburetor.
And a second cleaner chamber to be introduced into the engine,
Cleaner element installed in the connecting part of both cleaner chambers
It is an intake device for motorcycle engines equipped with
The fresh air intake port is located below the vehicle head pipe and at the first position.
It is provided in the center of the lower surface of the cleaner chamber near the front, and
The air room receives the fresh air from the first cleaner room as described above in the second room.
The introduction part of the bifurcated branch that leads to the downstream side of the leaner chamber, and this guide
New from the first cleaner room introduced by Inlet
It consists of a main room located on the downstream side where air gathers.
Introductory part of crotch branch is tapered toward the downstream side
The intake system for motorcycle engines, which is characterized by