JPH02128976A - Air cleaner device of saddle type vehicle such as motorcycle - Google Patents

Abstract

PURPOSE:To reduce the height of a fuel tank by installing an air cleaner for suction air in a recess bounded by a fuel tank bottom plate in inverted U-form in the front view, and forming an air cleaner element from a pair on the left and right to be accommodated at the left and right sides of air cleaner. CONSTITUTION:A fuel tank 22 of a motorcycle is constructed in inverted U-form in the front view, and a main frame 4 is fitted in a recess 23 formed at the undersurface of this fuel tank 22, which is so arranged as to stride over the main frame 4. An air cleaner 20 connected with a carburetor is equipped with a cleaner case 37, which strides the main frame 4 and presents inverted U-form in the front view, and accommodated in the recess 23 at the undersurface of fuel tank 22 together with carburetor. This cleaner case 37 is equipped with a case body 39having a left and a right openings 38 on its facade, and at its left and right sides, a vertically stretchingelement 49 in the form of a log circular tube is accommodated in the extent from an external air lead-in pipe 42 till a coupling pipe 48 mating therewith.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an air cleaner device for a saddle type vehicle such as a motorcycle.

(Prior Art) A motorcycle, which is an example of a straddle-type vehicle, usually has a body frame including a main frame extending rearward and downward from a saddle vibrator. A fuel tank is provided so as to straddle this main frame, and together with this, an air cleaner for intake air of the engine is provided.

In some of the above configurations, the air cleaner is composed of a cleaner case that straddles the main frame, and an element that is housed in the cleaner case above the main frame (
For example, Japanese Patent Application Laid-Open No. 62-83292).

(Problems to be Solved by the Invention) By the way, when the element is housed in the cleaner case above the main frame as in the above configuration, the volume of the air cleaner above the main frame becomes large. For this reason,
If a predetermined volume is to be secured in the fuel tank above the main frame, the height of the fuel tank must be increased by the increased volume of the air cleaner, as described above.

However, if you increase the height of the fuel tank as described above,
The center of gravity of the vehicle becomes higher, which is unfavorable in terms of handling stability.

(Object of the Invention) This invention was made in view of the above-mentioned circumstances, and it is possible to secure a predetermined capacity in the fuel tank portion above the main frame while reducing the height of this portion. The main purpose is to achieve a lower center of gravity, thereby improving maneuverability.

(Structure of the Invention) A feature of the present invention for achieving the above object is that the air cleaner elements are arranged in pairs on the left and right, and each side of the cleaner case is formed in an inverted U-shape as seen from the front, spanning the main frame. The point is that each of the above elements is housed in the .

(Example) Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 2, 1 is a motorcycle, and 2 is its body frame. This body frame 2 has a semi-double cradle shape. That is, this body frame 2 has a head vibrator 3 at its front part, and a main frame 4 extends rearward and downward from the top of this head vibrator 3, and furthermore, from the rear end of this main frame 4, a pair of left and right seats are connected. A pillar tube 5 extends downward, and a rear arm bracket 6 is attached to each lower end of the pillar tube 5.
is installed. On the other hand, a pair of left and right down tubes 7 extend rearward and downward from the lower part of the Radvib 3 and have their rear ends connected to the lower end of the rear arm bracket 6.
will be provided.

The front fork 8 is supported in a freely steerable manner by a steering shaft that is fitted into the steering shaft so as to be rotatable around the axis, and upper and lower brackets 8a and 8b that protrude from the steering shaft. be done. A front wheel 9 is supported at the lower end of the front fork 8, and a handle 10 is attached to the upper bracket 8a.

A rear arm 13 is pivotally supported on the rear arm bracket 6 by a pivot shaft 12 so as to be vertically swingable, and a rear wheel 14 is supported at the swinging end of the rear arm 13. Further, a shock absorber 15 is interposed between the upper part of the seat pillar tube 5 and the rear arm 13 via a link mechanism 16.

Reference numeral 18 denotes a 4-cycle parallel two-cylinder engine. This engine 18 is located inside the vehicle body frame 2. Its crankcase 18a is fastened to the vehicle body frame 2, and the left and right cylinders are tilted forward from the crankcase 18a. 18b is prominent. An intake hole is formed in each rear surface of both cylinders 18b, and a carburetor 19 is attached to each intake hole. In addition, these vaporizers 1
An air cleaner 20 is provided to clean the outside air drawn into the cylinder 18b through the cylinder 18b.

A sheet metal fuel tank 22 that supplies fuel to the carburetor 19
will be provided. This fuel tank 22 has an inverted U-shape when viewed from the front, and a recess 23 formed on the lower surface side of this fuel tank 22 fits into the main frame 4. In other words, this fuel tank 22 has an inverted U-shape. It is set up to straddle the. The fuel tank 22 is attached to the front and rear mounting brackets 2.
It is supported by the vehicle body frame 2 at an angle of 4°25. Further, the carburetor 19 and the air cleaner 20 are disposed in the recess 23 above both the cylinders 18b, and the recess 23
The effective use of In addition, 22a is a cap,
22b is a knee grip.

The engine 1 is located in front of the upper part of the grand tube 7.7.
8. A cooling radiator 27 is provided, which is supported by the town tube 7.7. Further, 28 is a cowling, and this cowling 28 has a substantially U-shape in plan view. That is, this cowling 28 is a front cowl 29 located in front of the head vibrator 3. A pair of left and right side cowls 30 extend rearward from both left and right ends of the front cowl 29 and reach the front side surfaces of the fuel tank 22.
It consists of 30. The front cowl 29 covers the head vibrator 3, the fuel tank 22, and the radiator 27 from the front, and each side cowl 30 covers the cylinders 18b and the radiator 27 from the outside.

On the other hand, a pair of left and right seat rails 32 extend rearward and upward from the rear end of the main frame 4. The rear end of the seat rail 32 is firmly supported by the rear arm bracket 6 by a back stay 33, and a seat 34 is mounted on the seat rail 32.

The engine 18 operates by sucking in outside air through an air cleaner 20 and a carburetor 19, and by sucking fuel from a fuel tank 22 through the carburetor 19. By transmitting the power of this engine 18 to the rear wheels 14, the motorcycle l can travel.

In FIG. 1, FIG. 3, and FIG. 4, the bottom plate 36 of the fuel tank 22 has side plates 36a, 36 facing left and right.
A and a ceiling plate 36b connecting the upper ends of these side plates 36a and 36a form an inverted U-shape when viewed from the front, and the portion surrounded by the outer surface of the bottom plate 36 serves as the recess 23. .

As described above, the air cleaner 20 disposed in the recess 23 is configured as follows. That is, this air cleaner 20 straddles the main frame 4 and has an inverted U shape when viewed from the front.
It has a letter-shaped cleaner case 37 made of resin.

The cleaner case 37 also includes a case body 39 having a pair of left and right openings 38, 38 on the front side, and the case body 39 is screwed to the upper surface of the main frame 4 at the left and right center portions with bolts 39a.

A cover plate 41 is provided to open and close each of the openings 38 and to be removably screwed to the edge of each opening 38 with a bolt 40. And this cover plate 41
A first outside air introduction vibe 42 that guides outside air into the case body 39 is integrally molded in the case body 39, and an upstream end 42a of the first outside air introduction vibe 42 extends downward along the outer surface of the cover @41.
On the other hand, the downstream end 42b is bent rearward, passes through the cover plate 41, and projects into the case body 39.

On the lower front surface of the case body 39, outside air is introduced into the upstream end 42a of each of the first outside air introduction vibes 42 (second outside air introduction vibes 43 are provided, respectively).

Each of the second outside air introduction vibes 43 is detachably attached to the front surface of the case body 39 with a bolt 44. To explain the second outside air introduction vibe 43 in more detail, its upstream end 43a protrudes outward;
The protruding end faces the outer surface of the side plate 36a and extends to the vicinity of the side plate 36a. On the other hand, the downstream end 43b of the second outside air introduction vibe 43 is bent upward, and the first outside air introduction vibe 4 is bent upward.
The upstream end 42a of 2 is removably fitted.

An eaves 45 is integrally molded on the upstream end 42a of the first outside air introduction vibe 42 so as to cover the gap between the upstream end 42a of the first outside air introduction vibe 42 and the downstream end 43b of the second outside air introduction vibe 43 from above. has been done. The eaves 45 prevents rainwater from entering the first outside air introduction vibe 42 and the second outside air introduction vibe 43 through the gap.

On the other hand, openings 47 are formed in the left and right bottom plates of the case body 39, and a connecting vibrator 48 made of rubber and elastic is removably fitted into the openings 47.

An upstream end 48a of this connecting vibe 48 protrudes forward and upward within the case body 39, while a downstream end 48b
is connected to the vaporizer 19.

In the above case, the positions of the left and right carburetors 19.19 are lowered by the amount that each cylinder 18b is tilted forward, and accordingly, the volume of the cleaner case 37 and the filtration area of each element 49 are increased to increase the air cleaner 20. The aim is to improve the filtration efficiency.

Further, each of the carburetors 19, 19 and the air cleaner 20 are disposed continuously above the cylinder 18b to improve the inertia effect due to the downdraft of intake air.

Furthermore, as shown in Fig. 1, the left and right connecting vibes 48.48
are located on the outside of the main frame 4 so as to sandwich the main frame 4 from the left and right sides.

On the other hand, the left and right carburetors 19.19 are located below the main frame 4, and are brought close to each other so that they overlap with the main frame 4 in plan view.
．． 19 are provided so as to be compact on the left and right sides.

For this reason, each of the connecting vibes 48 is inclined toward the center of the vehicle body as it moves downward, and in this case, each of the connecting vibes 48 is formed so as not to come into contact with the main frame 4.

Elements 49 are provided on each side of the case body 39 between each first outside air introduction vibe 42 and the corresponding connection vibe 48 . Each element 49 has a vertically elongated elliptical annular shape when viewed from the front, and is detachably attached to the inner surface of the cover plate 41 so as to surround the downstream end 42b of the first outside air introducing vibe 42. Each element 49 allows outside air to pass from the first outside air introducing vibe 42 to the connecting vibe 48,
At this time, this outside air is filtered to make it clean air.

In the above case, the one-car elements 49, 49 are located on the outside of the main frame 4 so as to sandwich the main frame 4 from the left and right sides. By the way, when the element 49 is disposed on the outside of the main frame 4 in this way, the provision of the element 49 generally restricts the shape of the fuel tank 22 and suppresses its capacity. . but,
In this embodiment, the element 49 corresponds to the front edge of the knee grip 22b in the left-right direction, and the outer surface of the fuel tank 22 is extended outward by the volume occupied by the element 49, that is, A predetermined capacity is secured here. Furthermore, this projecting portion 22c serves as a windbreak for the rider's knee N in the knee grip 22b, and is effectively utilized.

On the other hand, the front cowl 29 is formed with a pair of left and right outside air introduction ports 51,51. And motorcycles
When the vehicle is running, as shown by the arrows in each figure, the running wind is first introduced into the cowling 28 through the outside air inlet 51, 51, and then into the recess 23 of the fuel tank 22.
be introduced within. Then, out of this running wind, the side plate 3
The part that flows along the outer surface of 6a is the second outside air introduction pipe 4.
3 and the first outside air introducing vibrator 42, and is introduced into the cleaner case 37, where it is filtered by an element 49. The air that has been purified by this filtration is then sucked into the vaporizer 19 through the connecting vibrator 48 .

Note that, as shown by the imaginary line in FIG. 1, in the above configuration, a guide vibe 52 may be provided for guiding the traveling wind from the outside air introduction port 51 to the second outside air introduction pipe 43.

When cleaning each element 49 of the air cleaner 20 or replacing it with a new one, first, as shown by the imaginary line and arrow A in FIG. The front fork 8 is rotated in a direction away from the front side of the front fork 37. Then, the cover plate 41 is removed from the case body 39 by passing through the opened space and loosening the bolts 40.Next, the cover plate 41 is moved slightly upward together with the first outside air introduction vibe 42, and 1 Upstream end 42 of outside air introduction vibe 42
a is removed from the downstream end 43b of the second outside air introduction pipe 43.

Next, as shown by the imaginary line and arrow B in FIG. 1, the cover plate 41 is moved forward and the element 49 is extracted from the case body 39. After this, the element 49 is cleaned or replaced with a new one. Then, by performing the reverse operation to the above, attach the element 49 to the cleaner case 37.
If you store it inside, this replacement work will be completed.

1 and 3, 54 is a gas vibrator, one end of which is connected to the cylinder head of the cylinder 18b,
The other end is connected to a cleaner case 37. and,
The gas vibrator 54 returns the blow-by gas sent into the cylinder head to the carburetor 19 via the cleaner case 37.

(Effects of the Invention) According to the present invention, the cleaner case is formed so as to form an inverted U-shape as seen from the front astride the main frame, and the elements are housed in each of the left and right sides of the cleaner case. Compared to the case where the elements were housed in the cleaner case above the main frame, the surplus space above the main frame expands in the lateral direction by the fact that no element is present above the main frame. Therefore, if this space is used to expand the part of the fuel tank above the vehicle body frame, the height of the fuel tank can be lowered while maintaining the specified capacity, which in turn lowers the center of gravity of the vehicle. Improved handling stability is achieved.

Furthermore, since the elements are arranged as a pair on the left and right sides, the filtration area of the elements can be increased compared to the case where only one element is used in the past, and therefore the filtration efficiency can be improved.

(Margin below)

[Brief explanation of the drawing]

The figures show an embodiment of the invention, with FIG. 1 being a plan partial sectional view and FIG. 2 being a front side view of the motorcycle. 1. ・Helangin, Nku, 2 49... ・Motorcycle, 2. Body frame, 3. Dopipe, 4
・・Main frame, 18・・Work 20・・Air cleaner, 2
2.Fuel 3.Recess, 37.Cleaner case, element.

Claims (1)

[Claims] 1. A fuel tank, which extends rearward and downward from the head pipe and forms an inverted U-shape when viewed from the front, and an engine intake air cleaner are provided, and the cleaner case of this air cleaner is straddled over the main frame when viewed from the front. Inverted U
An air cleaner device for a straddle-type vehicle such as a motorcycle, which is formed in a shape of a letter, and includes a pair of left and right air cleaner elements, each of which is housed in each left and right side of a cleaner case.