JPH0316793Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to motorcycles, and in particular relates to the arrangement of an air cleaner, an intake system connected thereto, and a fuel tank.

[Conventional technology]

Generally, in a motorcycle, a fuel tank is placed in front of the driver's seat, and in the approximately triangular space formed below this fuel tank, the engine is placed on the front side, and the intake system such as an air cleaner carburetor is placed on the rear side. It has a structure that allows

[The problem that the idea aims to solve]

The above-mentioned conventional motorcycle has the following disadvantages.

While the vehicle is running, the intake system is warmed by the engine below, which causes the expanded air-fuel mixture to be sent to the engine, reducing charging efficiency.

Because the fuel tank is limited in height from top to bottom, it becomes long from front to back, and the bottom shape of the fuel tank is complicated to avoid interference with the intake system equipment below, making it impossible to maintain a large capacity given the area of the tank wall.

Since the fuel tank is located at the top of the vehicle, the center of gravity becomes higher when the tank is filled with fuel.

This idea was proposed against the above background, and it is possible to increase the filling efficiency of the air-fuel mixture, increase the capacity of the fuel tank relative to the area of the wall surface, and reduce the center of gravity even when the tank is full. The aim is to provide motorcycles that are not expensive.

[Means to solve the problem]

This idea fixes the front ends of a pair of left and right car body frames, each made of independent hollow members, that extend to the left and right and extend toward the rear of the car body, to the head pipes.
An air cleaner is placed in the space immediately behind the head pipe and sandwiched between the left and right body frames, and an air cleaner is placed in front of the engine, which is located in front of the pivot part that supports the rear fork located at the rear of the body frame. Equipped with a tilting cylinder,
positioning the cylinder below the air cleaner;
A carburetor connected to the cylinder and the air cleaner is arranged between the cylinder and the air cleaner, the cylinder, the carburetor, and the air cleaner are arranged in series in the vertical direction, and a fuel tank is arranged behind the air cleaner and the carburetor and above the engine. It is characterized by what it did.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

Reference numeral 1 denotes a pair of left and right upper vehicle body frames that extend from the upper side of the head pipe 3 to the left and right and extend rearward;
are a pair of left and right lower vehicle body frames that extend from the bottom of the head pipe 3 to the left and right and extend rearward; 4 is a front wheel; 5 is a front carrier; 6 and 7 are seats; 8
9 is the rear wheel, 9 is the main stand attached to the bracket 10, 11 is the side cover, 12 is the upper cover, 13 is the choke knob, and 14 is the engine 2.
5 is a horizontal cylinder portion, 15 is a fuel tank, 16 is a storage compartment, 17 is a connecting tube leading from the air cleaner 18 to the carburetor 19, and 20 is a cover that accommodates the connecting tube 17. The lower vehicle body frame 1 and the upper vehicle body frame 2 are made from mutually independent hollow members. Also, 2
1 is a fuel pipe, 21a is a spare fuel pipe, 2
2 is a fuel tank. 23 is an engine hanger, and this engine hanger 23 has a back plate portion 23a.
and left and right back plates 23b, and the horizontal section is U-shaped with the front open.Furthermore, the left and right upper parts have mounting plate parts 23c, which attach to the lower body frame 2 and the front and rear cross pipes. 24 by welding.

The engine 25 is supported on the vehicle body frame by bolts through holes 23d formed in the side plate portion 23b of the engine hanger 23, with the engine 25 positioned in front of the pivot shaft 29. Further, a pivot shaft 27 of a brake pedal arm 26 and a pivot shaft 29 of a rear fork 28 are fixed to the engine hanger 23.
Further, a tip 30a of a rear fender 30 is attached to the back plate portion 23b of the engine hanger 23.

Further, 31 is a connecting member for rotatably connecting the seat 6 to the bracket 32 on the upper vehicle body frame 1 side, and 33 is a seat support with a suction cup to which the seat 6 is attached. A head pipe gusset 34 supports the upper end of the cover 20. The above-mentioned upper vehicle body frames 1, 1 and lower vehicle body frames 2, 2
are welded and fixed to the upper and lower parts of the head pipe 3 at their front ends, and the lower body frame 2 is welded and fixed to the upper body frame 1 at the rear, and a cross pipe 24 is connected between the left and right body frames 1 and 2. , seat grip 36, seat bridge 37, and stay 38 are horizontally mounted to form a vehicle body frame.

The air cleaner 18 is disposed in a space C immediately after the head pipe 3, which is sandwiched from the left and right by the left and right upper vehicle body frames 1 and lower vehicle body frames 2. The air cleaner 18 and the lower carburetor 19 connected thereto are arranged above the horizontal cylinder section 14 at the front of the engine, and the horizontal cylinder section 14, the carburetor 19, and the air cleaner 18 are arranged in series in the vertical direction. Air cleaner 18 and horizontal cylinder section 14
are connected by an intake passage consisting of a connecting tube 17 and the like with a carburetor 19 interposed therebetween. The fuel tank 15 is located behind the air cleaner 18 and the carburetor 19 and above the engine 25 (here, the engine refers to an engine in which the engine body and transmission system, which are composed of a cylinder section, a crank chamber, etc., are integrated). Decorated.

The air cleaner 18 has a triangular prism shape that matches the triangular prism-shaped space C formed by the head pipe 3 and the vehicle body frames 1 and 2, and has suction pipes 18a each having a cross section of θ extending rearward from the apex. This suction pipe 18a is disposed on stepped portions 15a formed on the left and right sides of a fuel gauge 41 that protrudes from the center of the fuel tank 15.

The connecting tube 17 that communicates the air cleaner 18 and the carburetor 19 is covered with a cover 20, and the side part of this cover 20 accommodates a connection part (connector) of a wire harness (not shown) to a headlamp 39, etc. This is case 20a.

Further, the air cleaner 18 is attached to the upper vehicle body frame 1 with bolts, and the front portion 15b of the fuel tank 15 is rubber-floated to the lower vehicle body frame 2 via a bobolt 40.
The rear portion 15c is fitted and supported by the stay 38.

In the above configuration, the rear of the head pipe 3,
and a triangular prism-like space C in front of the fuel tank 15
is a space that has little utility value under normal circumstances, but by arranging the air cleaner 18,
This space C is utilized extremely effectively. Also,
With the air cleaner arrangement as described above, the suction pipe 18a of the air cleaner 18 can be made long as in the embodiment, and the length can be made most suitable for the engine, output, and intake noise reduction. Further, since the suction port 18b opens into the closed space formed by the top surface of the tank and the top cover 12, it is possible to prevent water, dust, etc. from entering during driving. Furthermore, this air cleaner 18 has an appropriate vertical positional relationship with respect to the carburetor 19 provided above the horizontal cylinder portion 14, and the length of the connecting tube 17, which has a large effect on engine output, can be appropriately selected. .

In addition, the intake passage that includes the air cleaner and carburetor 19 is located in front of the fuel tank 15, so these intake systems are less likely to be warmed up by the heat of the engine 25, and are able to take in the cold running air directly to the engine. 25 can be supplied. Therefore, the filling efficiency of the air-fuel mixture is increased.

In addition, the fuel tank 15 has a carburetor 19 located below.
The engine 25 does not have an intake system, and its lower end extends to near the top surface of the engine 25. Therefore, there is no need to make the bottom of the tank a complicated shape to avoid interference with other frame members, etc., as in the past, and the tank can be deep. As a result, the capacity can be increased relative to the area of the tank wall surface. Further, it is possible to reduce fluctuations in the liquid level due to the movement of the vehicle body, and it is also possible to suppress the phenomenon that fuel may or may not be sent to the carburetor 19 side when there is little remaining fuel.

Furthermore, as mentioned above, the deep fuel tank 1
5, compared to conventional models, even if the top surface of the tank 15 is kept at the same height, the center of gravity can be lowered by the depth of the tank, which in turn lowers the center of gravity of the entire vehicle. You can lower your center of gravity.

Note that the present invention is not limited to single-cylinder engines, but can also be applied to multi-cylinder engines. Furthermore, the pair of left and right vehicle body frames 1 and 2 extending rearward from the head pipe 3 are not limited to being divided into upper and lower parts as in this embodiment, but the present invention can also be applied to a structure in which they are integrated into one body frame. be.

[Effect of idea]

As explained above, according to the present invention, the following excellent effects are achieved.

The intake system, which consists of an air cleaner, carburetor, etc., is arranged in series directly above the cylinders at the front of the engine, and the engine reaches its highest temperature when it is moving; Since the air near the engine flows horizontally along the running wind, the intake system is not warmed by the engine, and the cold running air can be directly inhaled, increasing the filling efficiency of the air-fuel mixture. .

The pair of left and right body frames connected to the head pipe are each made of independent hollow members, and since these independent hollow members have higher rigidity than open pressed members, the desired wide angle with respect to the head pipe can be achieved. It can be connected with As a result, a large space can be formed immediately behind the head pipe, and an air cleaner of a desired size can be housed there. In addition, since the air cleaner can be placed close to the head pipe, the rear fuel tank can be placed in the front of the vehicle and as close as desired to the intake system and the engine below, which are arranged in series. ,
As a result, the degree of freedom in arranging the intake system and fuel system in a compact manner close to the engine is increased, and it is possible to prevent the components of the intake system and fuel system from interfering with other components.

The top surface of the fuel tank can be placed at almost the same height as the air cleaner located in the space immediately after the head pipe, and the bottom surface can be lowered to the top of the engine without considering interference with other equipment, simplifying the shape of the bottom surface. The depth of the tank can be increased. As a result, the capacity can be increased relative to the area of the tank wall surface. Furthermore, fluctuations in the liquid level can be suppressed and stable fuel supply to the carburetor can be realized.

As mentioned above, since the depth of the fuel tank can be increased, the center of gravity can be lowered compared to conventional models even if the top of the tank is kept at the same height, thereby reducing the nose type during braking.

[Brief explanation of the drawing]

Each figure shows one embodiment of the present invention. Figure 1 is a side view of the motorcycle, Figure 2 is a plan view of the same, and Figure 3 is a side view of the motorcycle.
The figure is an exploded perspective view of the vehicle body frame and various parts, FIG. 4 is a longitudinal sectional view of the main part, and FIG. 5 is a sectional view of the main part taken along the line -- in FIG. DESCRIPTION OF SYMBOLS 1... Upper vehicle body frame, 2... Lower vehicle body frame, 3... Head pipe, 14... Horizontal cylinder part, 15... Fuel tank, 15a... Step part, 17
... Connecting tube (intake passage), 18
...Air cleaner, 18a...Suction pipe, 19...
Carburetor, 23...Engine hanger, 25...
...engine, C...space.

Claims (1)

[Scope of Claim for Utility Model Registration] The front ends of a pair of left and right vehicle body frames each made of independent hollow members extending left and right to the rear of the vehicle body are fixed to the head pipe, and the left and right vehicle body frames are located in the space immediately behind the head pipe. An air cleaner is disposed in a space sandwiched by the frame, and an engine disposed in front of a pivot portion supporting a rear fork located at the rear of the body frame is provided with a cylinder inclined forward, and the cylinder is connected to the air cleaner. A carburetor connected to the cylinder and the air cleaner is arranged between the cylinder and the air cleaner, and the cylinder, the carburetor, and the air cleaner are arranged vertically in series, and behind the air cleaner and the carburetor and above the engine. A motorcycle characterized by having a fuel tank located at the top.