JPH0245281A - Intake device of engine for motorcycle - Google Patents

Abstract

PURPOSE:To make the size compact by disposing an intake box, storing an air cleaner element at a part between a pair of right and left main frames, at a recessed portion formed at the bottom part of a fuel tank, and protruding the upper end of intake pipe in an air cleaning chamber from the below. CONSTITUTION:A recessed part R is formed at the substantial central part of the bottom part of a fuel tank assembled at a pair of right and left main frames of a motorcycle, and an intake box 42 where a long cylindrical air cleaner element 43 is housed is arranged in this part R. At the part R, a recess extending in the fore and aft directions of the motorcycle is formed, and at the recess, a protrusion extending in the right and left directions thereof is formed. The box 42 is formed in a substantial lectangular form, and at the substantial central part of the upper face, an intake port 42b is formed, and further at the downstream of the element 43, an air cleaning chamber 42g is defined so as to extending in the fore and aft directions of the motorcycle. Then the upper end of the intake pipe 34 extending in the upper from each cylinder upper part is protruded from this chamber 42g so as to be aligned in a line in the right and left directions thereof.

Description

[Detailed description of the invention] The present invention relates to an intake device for a motorcycle engine.

A large number of components are assembled into the space of the vehicle body that makes up a motorcycle, but since there are certain restrictions on the space of the vehicle body, many components are assembled into this limited narrow space to improve performance. How to arrange them rationally in terms of top and appearance has been a long-standing issue.

For example, a motorcycle has been proposed in which an intake device is placed in a space formed between a fuel tank attached to the vehicle body and the engine, but in this type of motorcycle,
The space is occupied by a large intake device, and other large components such as batteries, electrical equipment boxes, etc. must be placed in other spaces.

The present invention was made by paying attention to such actual situation.
The main purpose is to provide an intake system that can be assembled into a compact configuration without complicating the engine surroundings, and to secure space for other components in the space between the fuel tank and the engine. In addition, the intake has an excellent sound insulation effect on intake noise! I provide the location.

Hereinafter, the present invention will be explained based on the drawings. FIG. 1 shows an example of a motorcycle equipped with an air intake device according to the present invention. This motorcycle is equipped with a V-type 4-cycle engine, and has a pair of left and right mains 7, one end of which is fixed to a head vibrator 11, and a fuel tank 2 at -412.
0 is assembled, and the engine 3 is attached to the left and right pair of r-fun tubes 13, one end of which is fixed to the hemovib 11.
0 is added. The engine 30 includes a front cylinder 31 that slopes forward and a rear cylinder 32 that slopes backward.
A carburetor intake pipe 33, 34 extending substantially vertically upward is connected to the upper part of each of the cylinders 31, 32. These form a space between the fuel tank 20 and the engine 30, and in this space, the intake system [40 and other WI
t, a battery 50 as a component is provided.

As shown in FIGS. 2 and 3, the fuel tank 20 has a recess R formed at the bottom of the fuel tank 20, approximately in the middle of the arrow, and has an air intake device I! 40 is the bottom I of the fuel tank 20! 21
, an air intake 542 (chamber box), and an air cleaner element 43.

A recess R of the bottom plate 21 of the fuel tank 20 (hereinafter referred to as 41 in relation to the intake system 40) has a recess 41 extending in the longitudinal direction of the vehicle body. A is formed within the recess 81541a, and a convex portion 41b extending in the left-right direction of the vehicle body is formed within the recess 81541a.

On the other hand, the chamber box 42 has a substantially rectangular parallelepiped shape that extends along the bottom plate 41, and has a rectangular air intake port 42b that is slightly elongated in the left-right direction of the vehicle body and is formed at a substantially central portion of its upper surface 42a. Further, in the upper surface 42m, a recess 41 of the bottom plate 41 extends in the longitudinal direction of the vehicle body along both left and right edges of the intake port 42b.
Two protrusions 42e facing a are formed, and a seal rubber 42d is fitted onto both protrusions 42c. The chamber box 42 includes two sealers,
? -42d is inserted into the recess 41a of the bottom plate 41, a predetermined gap is maintained, and the protrusion 41b of the bottom plate 41 faces the center of the suction port 42b of the chamber box 42. As a result, both seal rubbers 42d in the gap
An air flow passing through the intake air passage p is guided by the convex portion 41b of the bottom plate 41 and sucked into the chamber box 42 from the suction port 42b.

An air cleaner element 43 is housed within this chamber box 42 . This air cleaner element 43 is formed into a rectangular cylindrical shape, and its -MIr
The M mouth part 43a forms the inlet 42b.
e is housed in the chamber pock A42 in a state where it is fitted externally to the air cleaning chamber 42.e downstream of the air cleaner element 43. is located in the front and rear direction of the vehicle.

In addition, each intake pipe 33, 34 extending to the lower surface 42f of the chamber box 42 has each intake pipe 33, 34 extending to the lower surface 42f of the chamber box 42.
Chamber box 42 along with Annelle 33m and 34m
are airtightly fixed to the lower surface 42f of the air cleaning chamber 42. The seven channels 33a and 34a are arranged in a line in the left and right direction in front and behind the air cleaner element 43, respectively. It stands out.

In the intake system [40 configured in this way, air is sucked in as shown by the arrows in FIG. 2 due to the intake negative pressure generated by the driving of the engine 30. That is, engine 3
Due to the negative intake pressure of 0, the outside air passes through the intake air passage p formed by the bottom plate 41 and the chamber box 42, and passes through the bottom plate 4.
The purified outside air is guided by the convex portion 41b of 1 and reaches the inside of the air cleaner element 43 from the suction port 42b, is purified through the air cleaner element 43, and reaches the air cleaning chamber 42g.
34a passes through each intake 'l' 33.34, becomes an air-fuel mixture, and is led to each intake air 31.32 of the engine 30.

By the way, in the intake device 1140, the chamber box 42 containing the air cleaner element 43, which is a main component thereof, is disposed in the recess R formed in the fuel tank 20, and the upper surface 4 of the chamber box 42 is disposed in the recess R formed in the fuel tank 20.
2a and the bottom plate 41 (21) of the fuel tank 20 form the intake air passage p, the intake device 40 can be configured extremely compactly, and almost all of it can be accommodated within the recessed portion R. . Therefore, if the intake device 40 is adopted, as shown in FIG. 1, the space formed by the fuel tank 20 and the engine 30 will not be occupied so much, and in this remaining ff1 part, For example, large parts such as the battery 50 can be disposed therein, and the intake air passage p of the intake device 40 is connected to the bottom plate 41 of the fuel tank 20 and the chamber box 4 as described above.
2, the intake noise is less likely to leak to the outside, and a considerable amount of noise is muffled within the intake air passage p. Note that in the intake device 40,
The intake air passage p is secured by two seal rubbers 42d.

In the above embodiments, a motorcycle equipped with a type 4-cycle engine has been described as an example, but the intake device according to the present invention is assembled below a fuel tank so that the intake pipe extends upward. It is used in various motorcycles equipped with engines that perform

As is clear from the above description, the present invention has a fuel tank disposed on a pair of left and right main frames extending rearward from a head pipe, and an engine having a plurality of inclined cylinders arranged in a row on the left and right below the main frame. In the motorcycle to be installed, an intake box housing an air cleaner element is placed in a recess formed at the bottom of the fuel tank and between the pair of left and right main frames, and an air cleaning chamber downstream of the air cleaner element is placed between the front and rear of the vehicle body. The upper end of the intake pipe extending upward from the upper part of the cylinder projects into the air cleaning chamber so as to be lined up in a row in the left-right direction of the vehicle body.

Therefore, according to the present invention, the intake device can be configured compactly without protruding to the side of the vehicle width, and can be used in the space formed between the fuel tank and the engine and between the pair of left and right main frames. Space can be saved, intake efficiency can be improved, the intake pipe can be shortened, and costs can be reduced, and the sound insulation effect on intake noise can be improved.

[Brief explanation of the drawing]

FIG. 1 is a side view of a motorcycle employing the intake device according to the present invention, FIG. 2 is an enlarged longitudinal sectional side view of the intake device, and FIG.
The figure is a longitudinal sectional view taken along the line ■-■ in FIG. Explanation of symbols 12... Main frame 20... Fuel tank 3
0...Engine 31.32...Cylinder 3rd
figure

Claims (1)

[Claims] In a motorcycle in which a fuel tank is disposed on a pair of left and right main frames extending rearward from a head pipe, and an engine having a plurality of inclined cylinders arranged in a row on the left and right is disposed below the main frame, the fuel tank is disposed at the bottom of the fuel tank. An intake box containing an air cleaner element is arranged in the formed recess and between the pair of left and right main frames, and an air cleaning chamber downstream of the air cleaner element is located in the front-rear direction of the vehicle body, and the cylinder is placed in this air cleaning chamber. An intake device for a motorcycle engine, characterized in that upper ends of intake pipes extending upward from the upper part are projected so as to be lined up in a row in the left-right direction of the vehicle body.