JPS6239381A - Fuel feeder for scooter type car - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fuel supply device used in scooter-type motorcycles and tricycles.

[Prior art]

Conventionally, the fuel tank of scooter-type motorcycles is installed almost directly above the engine, and the difference in water head between the fuel tank and the carburetor is used to transfer the fuel in the fuel tank to the float chamber of the carburetor. is supplied to.

By the way, recently, the present applicant has proposed installing the fuel tank in front of the footboard for placing the feet, that is, for example, inside the leg shield, in order to secure storage space for, for example, a helmet under the seat. The application has already been completed.

According to this configuration, not only is there a large distance between the fuel tank and the engine's carburetor in the front and back, but also the bottom of the fuel tank is located below the float chamber of the carburetor. A fuel pump is installed in the supply path to forcibly pump fuel toward the float chamber.

[Problem that the invention seeks to solve]

However, in the configuration of this prior art, the fuel supply path connecting the fuel pump and the float chamber is long, so for example, if the vehicle is driven until there is no fuel in the fuel supply path, even if the fuel tank is refilled, the fuel will not be filled. It takes time for the fuel discharged from the pump to reach the float chamber.

For this reason, it is extremely difficult to fill the float chamber with fuel in a short period of time, resulting in problems such as reduced startability.

Means for Solving Problems] Accordingly, in the present invention, a space is provided between the front fork and the seat for the driver's feet, a fuel tank is disposed in front of this space, and the above-mentioned The scooter-type vehicle described above has an engine and a carburetor connected to the engine arranged at the rear of the space, and a fuel pump is provided in a fuel supply path connecting these fuel tanks and a float chamber of the carburetor, and - the above fuel supply path is branched between the fuel pump and the float chamber, and this branch pipe is connected to the highest liquid level of the fuel tank located at a higher position than the float chamber.

[Operation] According to this configuration, when the fuel tank is filled with fuel to the highest liquid level, a portion of this fuel flows directly into the float chamber through the branch pipe.

For this reason, even if the car is driven until there is no fuel in the fuel supply path from the fuel tank to the float chamber, or even if there is no fuel in the fuel supply path at all like when the car was new, the fuel tank can be filled with fuel as described above. If this is satisfied, fuel will be supplied into the float chamber from the branch pipe prior to the fuel being pumped by the original fuel pump. Furthermore, when the fuel pump is activated, this fuel is added to the fuel pumped by the pump, so there are two fuel supply systems to the float chamber.

Therefore, no time or effort is required for the fuel in the float chamber to reach an appropriate level, and good startability can be ensured.

[Embodiments of the invention]

An embodiment of the present invention will be described below based on the drawings in which the present invention is applied to a scooter type motorcycle.

Figure 2 birth number 1 shows an underbone-shaped frame,
This frame 1 is largely bent downward between a front fork 2 that supports a front wheel 2a and a rear seat 3, and a footboard 5 is installed on this bent portion 4. A leg shield 6 that rises upward is continuously provided at the front end of the footboard 5, and a wide space 7 is secured between the leg shield 6 and the seat 3 for placing the driver's feet. ing.

Further, a swing type engine unit 8 is pivotally supported at the rear end of the bending portion 4 . Engine unit 8 of this embodiment
is a combination of a two-stroke engine 9 and a transmission case 1o that houses a belt-type continuously variable transmission. It supports the rear wheels 11 which are driven by.

Note that the area from below the seat 3 to around the engine 9 is covered with a cover 12.

On the other hand, a fuel tank 13 is arranged inside the leg seal tube located in front of the space 7. A cylindrical inlet 16 that is opened and closed by a tank cap 15 is formed on the top surface of the fuel tank 13, and the bottom of the fuel tank 13 is a float chamber for a carburetor 14 connected to the engine 9! 4
It protrudes below a. Therefore, as shown in FIG. 1, the fuel level L2 in the float chamber 4a is
is located above the lowest fuel level L1 in the fuel tank 13. And these fuel tanks 13
and the float chamber 14a are in communication with each other, and the piping structure for this communication will be described below.

That is, the fuel outlet 17 at the bottom of the fuel tank 13 and the float chamber 14a are connected by a communication pipe 18 as a fuel supply path, and after the communication pipe 18 is led out from the fuel outlet 17, it is connected to the float chamber 14a. It is guided rearward through a position lower than the lowest liquid level L1, that is, below the footboard 5, and is connected to the float chamber 14a. and,
A fuel pump 19 is installed in the middle of this communication pipe 18 for forcibly pumping fuel into the float chamber 14a.

Although an electromagnetic pump is used as the fuel pump 19 in this embodiment, a pulse pump whose driving source is, for example, the pulsating pressure in the crank chamber of the engine 9 may also be used.

Furthermore, the communication pipe 18 is connected to the float chamber L rather than the fuel pump 19.
4a, and this branch pipe 20 is guided forward through below the footboard 5, which is lower than the lowest liquid level L1 of the fuel tank 13.

The front end of the branch pipe 20 is raised in front of the footboard 5, and the upper end of the branch pipe 20 is located in the second part of the fuel tank 13, that is, at a position higher than the liquid level L1 in the float chamber 14a by a head difference H1. It is connected below the liquid level of the highest liquid level L3 located at . Therefore, when the fuel tank 13 is filled with fuel, the fuel also flows into the branch pipe 20.

Note that the fuel outlet 17 of the fuel tank 13 and the branch pipe 20
A fuel filter 21 is provided at the downstream end of each of the fuel filters.

According to one embodiment of such a configuration, the branch pipe 20 branched between the fuel pump 19 and the float chamber 14a is connected to the liquid at the highest liquid level L3 of the fuel tank 13 located at a higher position than the float chamber 14a. Since it is connected below the surface, for example, the vehicle can be driven until there is no fuel in the fuel supply path from the fuel tank 13 to the float chamber 14a, or even when there is no fuel in the fuel supply path at all, such as when the car is new. When the fuel tank 13 is filled with fuel up to the highest liquid level L3, a portion of this fuel flows directly into the float chamber 14a through the branch pipe 20. Therefore, float chamber 4
A is supplied with fuel from the branch pipe 20 before the fuel pumped by the original fuel pump 19, and the fuel from the branch pipe 20 is added to the fuel pumped by the fuel pump 19. There are two fuel supply systems to the float chamber 14a. Therefore, there is an advantage that no time or effort is required for the fuel in the float chamber 4a to reach the appropriate liquid level L2, and good startability can be maintained.

Note that the vehicle according to the present invention is not limited to a motorcycle, but may also be a tricycle having two rear wheels.

〔Effect of the invention〕

According to the present invention described in detail, the fuel level in the float chamber reaches the appropriate level within a short time, so it does not require time or effort to supply fuel and provides good starting performance. can be secured.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a schematic diagram of a fuel supply route, and FIG. 2 is a partially cutaway side view of a scooter type motorcycle. 2...Front fork, 3...Seat, 7...
Space, 9...Engine, 13...Fuel tank, 14
... Carburetor, 14a... Float chamber, 18... Fuel supply path (communication pipe), 19... Fuel pump, 20...
- Branch pipe (branch pipe). Applicant's agent Patent attorney Takehiko Suzue Figure 1

Claims (1)

[Claims] A space for the driver's feet is provided between the front fork and the seat, a fuel tank is placed in front of this space, and an engine is connected to the engine behind the space. In a scooter type vehicle in which carburetors are respectively arranged and a fuel pump is provided in a fuel supply path connecting these fuel tanks and a float chamber of the carburetor, the fuel supply path is branched between the fuel pump and the float chamber, A fuel supply device for a scooter type vehicle, characterized in that this branch pipe is connected to the highest liquid level of a fuel tank located higher than a float chamber.