JPH0986467A - Intake system mud proof structure for unit swing type engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a vehicle compact via the reduction of a lower fender size, enable a sufficient proof effect to be expected against mud, and eliminate a trouble even in the case of adjusting a carburetor. SOLUTION: This intake system mud proof structure A for a unit swing type engine is provided with a lower fender 5A having a shield 13 to cover the immediate rear part of a carburetor 9 laid in the vicinity of a position forward of the rear wheel upper part of a motorcycle or a motor tricycle equipped with a unit swing type engine.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake system mudproof structure for a unit swing type engine. Specifically, of the intake system in the so-called unit swing type engine, in which the transmission case is integrally formed with the crankcase and also functions as a swing arm and swings with the rear wheels,
In particular, the present invention relates to an intake system mud-proof structure for a unit swing type engine that prevents foreign matter such as muddy water and dust (hereinafter referred to as “muddy water”) from adhering to a vaporizer.

[0002]

2. Description of the Related Art In scooters and threeers equipped with a unit swing type engine, a carburetor, which is one of the intake systems, is arranged near the upper front of the rear wheels. By the way, when these intake systems are arranged near the rear wheels, muddy water splashed up by the rear wheels adheres to the carburetor, which is not preferable. Therefore, in the upper part of the outer periphery of the rear wheel,
Mudguards are arranged.

As shown in FIGS. 13 and 14, the mudguard 1 includes a lower fender 5 that swings together with a unit swing type engine 3 of a motorcycle 2 (however, only the rear portion of the vehicle is shown in the drawings), and a lower fender fixed to a vehicle body frame. 5 and upper fenders 7 located on the upper side. The reference numerals 8 and 9 denote carburetors arranged near the rear wheel and the upper front portion thereof, respectively.

As shown in FIG. 13, the lower fender 5 is arranged such that the outer circumference of the upper front portion of the rear wheel 8 is small, that is, so as to cover a part of the rear wheel 8, or depending on the vehicle type to which the lower fender 5 is attached, as shown in FIG. As shown in FIG. 7, the upper outer periphery of the rear wheel 8 is arranged to be large, that is, it is arranged so as to cover substantially the upper half of the rear wheel 8.

However, as shown in FIG. 13, when the lower fender 5 is small, when muddy water or the like is splashed up by the rear wheel 8 toward the carburetor 9, it is impossible to prevent the muddy water from proceeding to the carburetor 9. That is, the mudproof effect of the lower fender 5 cannot be expected so much. Also, as shown in FIG. 14, if the lower fender 5 is large, the lower fender 5 and the upper fender 7 do not come into contact with each other when the rear wheel 11 swings upward even though there is a mudproof effect.
The distance between the upper fender 7 and the upper fender 7 must be increased considerably. Therefore, the vehicle becomes larger. Thus, there is room for improvement whether the lower fender 5 is made smaller or larger.

Therefore, the vaporizer itself is provided with a cover body capable of covering the vaporizer, for example, as disclosed in JP-A-62-178763 and JP-A-63-1767.
No. 89 publication. By doing so, it is possible to prevent muddy water or the like from being applied to the vaporizer, and it is possible to make the lower fender 5 smaller.

However, in the case where the cover for covering the entire carburetor is provided, the cover must be removed when adjusting the carburetor, which is troublesome to handle.

[0008] Therefore, it has been desired to provide a new technique that can make the vehicle smaller by reducing the size of the lower fender, can expect a sufficient mud-proofing effect, and does not hinder the adjustment of the carburetor.

[0009]

SUMMARY OF THE INVENTION The present invention has been invented in view of the above problems, and the problem to be solved is to reduce the size of a lower fender to reduce the size of a vehicle and also to prevent mud. (EN) It is an object to provide an intake system mudproof structure for a unit swing type engine, which can be sufficiently expected and does not hinder the adjustment of a carburetor.

[0010]

The present inventor has taken the following means in order to solve the above problems. That is, the intake system mud-proof structure of the unit swing type engine of the present invention is provided with the eaves piece for covering the carburetor arranged near the front upper part of the rear wheel of the motorcycle equipped with the unit swing type engine immediately after the lower fender. I did it.

Therefore, according to the present invention, since the eaves piece for covering the carburetor arranged near the front upper part of the rear wheel is provided immediately after that, the lower fender, which is one of the mudguards, is provided.
The muddy water, which is sprung up toward the upper part of the rear wheel by the rotation of the rear wheel, is blocked by the eaves piece and cannot reach the carburetor.
No muddy water will hit the vaporizer. Moreover, the eaves piece is
Since it is immediately after the vaporizer, the clearance between the eaves and the vaporizer can be said to be extremely small. Therefore, a sufficient mud-proof effect can be expected. Therefore, it is not necessary to increase the size of the lower fender itself, which contributes to downsizing of the vehicle. Further, since the entire carburetor is not covered with the eaves piece, it is not necessary to remove the eaves piece from the lower fender when adjusting the carburetor. Therefore, the presence of the eaves is convenient because it is not difficult to adjust the carburetor.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in detail based on the illustrated embodiments with reference to the drawings. FIG. 1 is a schematic perspective view of a main part of a motorcycle in which an intake system mud protection structure for a unit swing type engine according to the present invention is adopted. FIG. 2 is an intake system mud protection structure A for a unit swing type engine according to the present invention. FIG. 3 is a partial enlarged side view showing the latter half of FIG. 2, FIG. 4 is an enlarged view of a main part of FIG. 3, FIG. 5 is a plan view of FIG. 4, and FIG. The figure which shows the state which removed the air cleaner from the state of FIG. 3, FIG.
8 is an enlarged side view of the lower fender, FIG. 8 is a partially cutaway plan view as seen from the direction of arrow VIII in FIG. 7, FIG. 9 is a front view as seen from the direction of arrow IX of FIG. 7, and FIG. 10 is the left side surface of the air cleaner 26. 11 is a right side view of the air cleaner 26, and FIG. 12 is a cross-sectional view of FIG. 10 taken along a virtual cutting plane including the line XII-XII and seen in the arrow direction.

It should be noted that the difference between the one described in the prior art and the present invention is that in the present invention, the eaves piece 1 which has not been conventionally provided in the lower fender 5 which covers the outer periphery of the upper front portion of the rear wheel 8 in a small size.
Since it is only the point where 3 is provided and the portion related to this eaves piece 13, the same reference numerals are given to the same portions and the description thereof will be omitted.

Therefore, it can be said that the intake system mudproof structure A of the unit swing type engine according to the present invention is provided with the eaves piece 13 which has not been present in the prior art in the lower fender 5 which is a constituent member of the mudguard 1 described in the prior art. Further, the lower fender according to the present invention is also intended to reduce the lower fender as described in the problem thereof. Therefore, the lower fender according to the present invention uses a lower fender that covers the outer periphery of the upper front portion of the rear wheel 8. is there. For this reason, since it is necessary to distinguish it from a larger lower fender that covers almost the upper half of the rear wheel 8, the reference numeral 5A is used for the lower fender described below.

A unit swing type engine 3 (hereinafter, simply referred to as "engine 3") is mounted on the rear half of the motorcycle 2 and includes a rear wheel 8 and a carburetor 9 arranged near the upper front of the rear wheel 8. In between, a lower fender 5A slightly covering the upper front part of the rear wheel 8 is attached to the central portion of the upper edge of the transmission case 3a of the engine 3 by an appropriate fixing means such as a screw.

On the left side of the vehicle of the lower fender 5A, as shown in FIG.
As can be seen from FIGS. 5 and 9, the eaves piece 13 is integrally formed. When the eaves piece 13 is seen from the left side of the vehicle,
As can be seen from FIGS. 6 to 7, the L-shape is opened at an obtuse angle and laid on its side to have a shape as seen from the back side thereof, and a vertical surface portion 13a extending in the vertical direction and a vertical portion 13 are formed.
It is composed of an inclined surface portion 13b which is continuously provided at the upper end of a and is inclined forward with an obtuse angle with respect to the vertical portion 13a.

Further, the inclined surface portion 13b has a shape such as a deformed rectangular plate material when viewed in plan as shown in FIG. Specifically, one corner 13b ₁ (indicated by a creative line) of the long rectangular plate material, and this one corner 1
The other corner 13b ₂ in the longitudinal direction with respect to 3b _{1 is} cut at a right angle, and in a cross cut line shape, that is, an arc shape, which is formed when the lower fender 5A and the other corner 13b ₂ of the rectangular plate member are penetrated. And those corners 1
3b ₁ 13b ₂ has a rectangular cutout corner portion 15 and a circular arc cutout corner portion 17, respectively.

Further, the vertical portion 13a extending downward in the vertical direction is formed at another corner portion 19 in the edge direction with respect to the arc-shaped cutout corner portion 17. Further, it extends downward from one edge 21 (see FIG. 5) located between the right-angled cut corner 15 and the arc-shaped cut corner 17 of the inclined surface portion 13b toward the front surface 5A ₁ of the lower fender 5A. A substantially triangular rib 23 (see FIGS. 4, 6, and 8) is integrally formed.

Of the eaves piece 13 having the above-mentioned shape, one edge 13c (13) of the side facing the rib 23 (on the left side of the vehicle).
It is also one edge of a and 13b. ) Is supported by being fitted to a labyrinth 27, which will be described later, of the air cleaner 26 attached to the upper edge of the transmission case 3a of the engine 3 by an appropriate fixing means such as a screw.

The labyrinth 27 is a groove provided on the outer wall surface 26a ₁ of the air cleaner box 26a, which is a case body of the air cleaner 26, on the vehicle center side so as to match the shape of the edge 13c of the eaves piece 13. Labyrinth 2
7 shows that the outer wall surface 26a is provided as a recessed portion on the inner side of the air cleaner 26 (see FIGS. 4 and 5), but is parallel to the outer wall surface 26a with a space corresponding to the thickness dimension of the edge 13a. Alternatively, the plate members may be formed so as to protrude, and further, may be formed by plate members formed in conformity with the shape of the one edge 13a.

When the eaves piece 13 is fitted into the labyrinth 27, the eaves piece 13 is sized and arranged so as to cover the carburetor 9 arranged near the front upper part of the rear wheel immediately after that. Has become. Note that FIG. 4 and FIGS.
Reference numeral 29 denotes a boss portion integrally formed with the lower end of the vertical portion 13a of the eaves piece 13 for attaching the lower fender 5A to the transmission case 3a by a fixing means such as a screw.

However, in the intake system mudproof structure A of the unit swing type engine constructed as described above, the eaves piece 13 for covering the carburetor 9 arranged in the vicinity of the front upper part of the rear wheel immediately after it is mudguarded. Since it is provided for the lower fender 5A, which is one of the first items, the muddy water or the like that is splashed up forward by the rotation of the rear wheel 8 is blocked by the eaves piece 13 and does not reach the carburetor 9. No muddy water will hit the area.

Moreover, since the eaves piece 13 is immediately after the vaporizer 9, the clearance l (see FIGS. 4 and 6) between the eaves piece 13 and the vaporizer 9 can be said to be extremely small, so that it is sufficient. A mudproof effect can be expected. Therefore, it is not necessary to increase the size of the lower fender itself, which contributes to downsizing of the vehicle. Further, since the carburetor 9 is not entirely covered by the eaves pieces 13, it is not necessary to remove the eaves pieces 13 from the lower fender 5A when adjusting the carburetor 9. Therefore, the presence of the eaves piece 13 does not make it difficult to adjust the carburetor 9, which is convenient.

[0024]

According to the present invention, the lower fender can be made smaller to reduce the size of the vehicle, the mud-proof effect can be expected sufficiently, and the carburetor can be adjusted without any trouble.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of essential parts of a motorcycle in which an intake system mudproof structure for a unit swing type engine according to the present invention is adopted.

FIG. 2 is an overall schematic side view of a motorcycle in which an intake system mudproof structure for a unit swing type engine according to the present invention is adopted.

FIG. 3 is a partially enlarged side view showing the latter half of FIG.

FIG. 4 is an enlarged view of a main part of FIG. 3;

FIG. 5 is a plan view of FIG.

FIG. 6 is a view showing a state in which an air cleaner is removed from the state shown in FIG.

FIG. 7 is an enlarged side view of the lower fender.

FIG. 8 is a partially cutaway plan view as seen from the direction of arrow VIII in FIG.

9 is a front view seen from the direction of arrow IX in FIG. 7.

FIG. 10 is a left side view of the air cleaner.

FIG. 11 is a right side view of the air cleaner.

FIG. 12 is a cross-sectional view of FIG. 10 taken along a virtual cutting plane including the line XII-XII and seen in the arrow direction.

FIG. 13 is a diagram for explaining a conventional technique.

FIG. 14 is a diagram for explaining another conventional technique.

[Explanation of symbols]

 A unit Swing engine intake system mud protection structure 1 Mudguard 2 Motorcycle 3 Engine 5A Lower fender 8 Rear wheel 9 Vaporizer 13 Eaves piece

Claims (1)

[Claims] 1. An intake system mud protection system for a unit swing type engine, which comprises a lower fender with an eaves piece covering a carburetor arranged in the vicinity of an upper front portion of a rear wheel of a motorcycle or a three-wheeled vehicle equipped with a unit swing type engine. Construction.