JPS6234876A - Fuel feeder for 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] (Industrial Application Field) The present invention supplies fuel to a carburetor located below a fuel tank via a fuel supply path passing below the carburetor. This invention relates to a vehicle fuel supply system.

(Background of the Invention) In scooter-type vehicles, etc., a fuel tank is arranged in the leg shield below the steering bar handle, and fuel is supplied to the carburetor through a fuel pipe that runs inside the footrest below the carburetor. Conventionally, there are In this case, conventionally, an electromagnetic fuel pump has been provided, and the fuel pump has been configured to forcefully feed the fuel to the carburetor. Therefore, there was a problem in that an expensive electromagnetic fuel pump was required.

There are also models that have a manual fuel cock near the carburetor, but in this case it is troublesome to open and close the fuel cock.

Therefore, it is conceivable to provide an automatic fuel cock near the carburetor that opens using the engine's intake negative pressure. However, if part of the fuel supply route connecting the fuel tank and carburetor passes through the side of the carburetor, if air enters this fuel supply route when the fuel tank is empty, the automatic A problem arises in that air enters the fuel cock and the fuel cock does not operate properly, making it impossible to send fuel.

(Object of the Invention) The present invention has been made in view of these circumstances, and although an inexpensive automatic fuel cock is used instead of an expensive electromagnetic fuel pump, air is not allowed to enter the fuel supply path. To provide a fuel supply device for a vehicle that can reliably supply fuel to a carburetor even when fuel is injected.

(Structure of the Invention) According to the present invention, the object is to provide a vehicle equipped with a carburetor located below a fuel tank, and a fuel supply path passing below the carburetor and supplying fuel from the fuel tank to the carburetor. , an automatic fuel cock located above the carburetor in the fuel supply route and opening the fuel supply route using engine intake negative pressure; and an air vent connected to the fuel supply route at a higher position than the fuel cock. This is achieved by a fuel supply system for a vehicle, which is characterized by comprising a float type relief valve. That is, by discharging the air that has entered the fuel supply path to the atmosphere through the relief valve, the automatic fuel cock is always filled with fuel and the fuel cock can be operated.

(Embodiment) Fig. 1 is a side view of an embodiment of the present invention, Fig. 2.3.4 is a front view, partially sectional left side view and right side view of an automatic fuel cock, Fig. 5. 6 is a sectional view taken along the line V-V and Vl--Vl in FIG. 3, and FIG. 7 is a sectional view of the relief valve.

In FIG. 1, reference numeral 10 indicates a frame. The frame L10 includes a steering shaft cylinder 12, one front frame 14, and a pair of left and right rear frames 16 (16a, 16b) extending obliquely L rearward from the front frame 14. A steering shaft held in a steering shaft cylinder 12 so as to be rotatable left and right has one front steering wheel 18 and a steering bar handle 2.
0 is attached.

Reference numeral 22 denotes a moving crab unit located below the rear frame 16, in which a forced air-cooled two-stroke horizontal engine 24 and a transmission case 26 are integrally assembled. The front part of the movable crab knit 22 is connected to the rear frame 16 via a link 28 so as to be able to swing up and down. The rear part of the transmission case 26 is elastically supported by a buffer unit 30. 32 is a rear wheel attached to the rear part of the transmission case 26.

The rear frame 16 is bent in the shape of two steps, with the front part 16A being lower than the upper edge of the rear wheel 32 in the empty state, and the rear part 16B being lower than the upper edge of the rear wheel 32 in the empty state.
It is higher than the upper edge of 2. Left and right rear frame 16
An arc-shaped seat support bracket 34 is fixed to the rear portion 16B of the seats a and 16b so as to protrude upward. In front of this seat support bracket 34 and in the rear frame 1
A large storage box 36 is disposed in the space above the front section 16A of 6. Since the rear frame 16 is disposed below the storage box 36 in this way, the left and right width of the opening of the storage box 36 is not limited by the spacing between the rear frames 16, and the opening is larger than the storage box 36. 36. Therefore, as shown in FIG. 2, it is possible to make the storage box 36 capable of accommodating a full-face helmet 38.

Reference numeral 40 denotes a long driving seat from front to back, the front end of which is attached to the upper part of the front end of the storage box 36 with a hinge 42 so that it can be opened and closed, and the rear part of the seat is attached to a locking device (not shown) provided on the bracket 34. It is lockable.

A substantially plate-shaped footrest 44 is formed below between the steering bar handle 20 and the driver's seat 40 and covers the lower part of the front frame 14 and the front part of the rear frame 16. It is a purifier, and the left and right rear frames 16a,
It is housed in the footrest 44 so as to be located between the footrests 16b and 16b.

48 is a carburetor, which connects the engine 24 and the air purifier 4.
It is arranged near the upper part between 6 and 6.

The intake air outflow side of the carburetor 48 is fixed to the upper surface of the engine 24 by an intake pipe 50. The inlet side of the vaporizer 48 is connected to the air purifier 46 by a flexible duct 52, ie, a rubber bellows.

54 is a fuel tank located above the carburetor 48. The front part of the footrest 44 is connected to a leg shield 56 that surrounds the steering shaft cylinder 12, front frame 14, etc. from the front and back, and the fuel tank 54 is housed within this leg shield 56.

58 is a carrier cover. This rear cover 58 is formed to cover the moving crab knit 22 and the upper side of the rear wheel 32 from the side of the storage box 36. The upper edge of the rear cover 58 faces inside the lower edge of the driver's seat 40. The front lower part of this rear cover 58 is connected to the footrest 44.

60 is an automatic fuel cock, which is installed above the carburetor 48. The height of this fuel tank 0 is approximately the same as the bottom of the fuel tank 54.

This fuel cock 70 is connected to a base plate 62 as shown in FIGS.
Then, the intermediate plate 64 and the cover 66 are stacked with the two diaphragms 68 and 70 in between.

These diaphragms 68 and 70 define a diaphragm chamber 72 on the substrate 62 side and a negative pressure chamber 74 on the cover 66 side. A plunger 76 is fixed to the diaphragm 68 , 70 through the intermediate plate 64 , and this plunger 76 is connected to the cylinder portion 7 formed on the base plate 62 .
Together with 8, it forms a plunger type on-off valve. Note that the peripheral edge of this cylinder portion 78 projects in the direction of the diaphragm 68 in a comb shape, and serves as a guide portion 80 for the plunger 76 . An O-ring 82 is fitted into the cylinder portion 78 to seal the plunger 76 and the cylinder portion 78 and absorb the impact when the plunger 76 hits the cylinder portion 78. 84 connects the plunger 76 to the cylinder portion 78
It is a coil spring that returns it to the side.

3.4.6, 86 is a negative pressure supply port, and this negative pressure supply port 86 is connected to a passage 88 in the substrate 62, as shown in FIG.
It communicates with the negative pressure chamber 74 (FIG. 5) via a check valve 90 provided on the intermediate plate 64 and a passage 92 provided on the cover 66. This negative pressure supply port 86 is communicated with the intake pipe 50 downstream of the throttle valve of the carburetor 48 through a tube 94 (see FIG. 1). A check valve 90 is installed in the naori bar 66.
A small diameter orifice 96 is provided to bypass the (FIG. 6).

98 is a fuel inlet, and this inlet 98 is connected to pipe 1.
00 to the fuel tank 54. That is, the fuel tank 54 and this inlet 98 are connected by a pipe 100 that passes through the footrest 44 which is lower than the carburetor 48 .

Fuel supplied from the fuel tank 54 to the inlet 98 through the pipe 100 enters the filter chamber 104 through a fuel passage 102 (FIG. 3) formed substantially perpendicular to the substrate 62.
Furthermore, a filter 106, a strainer 108, a fuel passage 1
10 (FIG. 5) and into the diaphragm chamber 72.

Reference numeral 112 denotes a fuel outlet, which communicates with the cylinder portion 78 through a fuel passage 114 (FIG. 5).

Reference numeral 116 denotes a float type relief valve, which is located below the rear of the driver's seat 40. As shown in FIG. 7, this relief valve 11B includes a valve body 120 that opens and closes the atmosphere communication hole 118 from below, and a float chamber 1 below the valve body 120.
22, and when the valve body 120 is pushed upward by the buoyancy of the float 124, the valve body 120 closes the atmosphere communication hole 11B. Note that the valve body 120
A buffer spring 126 and a push rod 128 are interposed between the float 124 and the valve body 1 due to the vibration of the float 124.
20 is suppressed to improve liquid tightness when the relief valve 116 is closed. The float chamber 122 of the relief valve 116 is connected to the outlet 112 of the fuel tank 0 through a pipe 130, and is connected to the float chamber (not shown) of the carburetor 48 through a pipe 132. Note that the atmosphere communication hole 11B of the relief valve 116 opens to the atmosphere at the highest position of the fuel supply path higher than the upper surface of the fuel tank 58.

Next, the operation of this embodiment will be explained. When the inside of the intake pipe 50 of the engine 24 becomes negative pressure, the negative pressure chamber 74 of the fuel tank 0 is pulled to negative pressure by the pipe 94, and the plunger 76 moves toward the negative pressure chamber 74 side against the spring 84. When the pressure inside the intake pipe 50 becomes positive, the check valve 90 closes, so the negative pressure chamber 7
4 does not have positive pressure at 8, but orifice 9
6 flows into the negative pressure chamber 74. Therefore, when the internal pressure of the intake pipe 50 changes due to the rotation of the engine 24, the plunger 76 vibrates in synchronization with the engine rotation, and the plunger 76 vibrates in synchronization with the engine rotation.
6 is pushed by the spring 84 and returns, the cylinder part 7
The fuel in 8 is pushed out to the outlet 112 side. From this outlet 112, the fuel is further conveyed by pipes 130, 132 to the float chamber of the carburetor 48.

Now when the fuel is empty, pipe 100. Air enters the fuel supply path consisting of the fuel tank 0, pipes 130, 132, and the like. When the fuel tank 54 is refueled in this state, the air that has entered the fuel supply path is discharged to the atmosphere from the relief valve 116 located at the highest position of the fuel supply path. Therefore, the fuel tank 0 is reliably filled with fuel. Therefore, when the engine 24 is started, the fuel outlet 0 operates normally due to the intake pulsation, and the fuel is transferred to the pipe 130.132.
Send to. When the fuel reaches the relief valve 116 and the float chamber 122 is filled with fuel, the float 124
0 to close the atmospheric communication hole 118 liquid-tightly. Therefore, fuel will not leak out.

In addition, in this embodiment, since the relief valve 116 is provided in the middle of the fuel passage between the fuel tank 0 and the carburetor 48, the temperature of the carburetor 48 may rise excessively by L during driving, and the fuel in the float chamber may become a gas. Even if this gas flows back into the pipe 132, the gas is discharged to the outside through the relief valve 116.

Therefore, this gas will not flow back until the fuel reaches zero. Therefore, according to this embodiment, even if vapor lock occurs, fuel can be quickly supplied to the float chamber, and problems such as engine stoppage due to insufficient fuel supply are less likely to occur.

Since the fuel head 0 is provided above the carburetor 48, the head difference between the fuel tank 54 and the fuel head 0 becomes small, and this head difference causes the inconvenience that the fuel head 0 remains open when the engine is stopped. do not.

FIG. 8 is a side view showing a second embodiment of the present invention. In this embodiment, a relief valve 116 is provided at a position lower than the upper surface of the fuel tank 54, and a hose 13 is connected to an atmosphere communication hole 118 of the relief valve 116.
4 is connected to the relief valve 146 so that when fuel overflows, it is guided to the ground.

Further, in this embodiment, a pipe 136 that leads the fuel from the fuel tank 0 to the carburetor 48 is connected to the float chamber 122 of the relief valve 11B by a single pipe 138. Therefore, there is an advantage that the pipe 130° 132 in the embodiment described above is shortened.

FIG. 9 is a side view of the third embodiment, showing the fuel tank 54.
The middle of a pipe 100 connecting the fuel tank 0 and the fuel tank 0 is connected to a relief valve by a pipe 140.

In FIG. 1O, an auxiliary tank 142 is provided in the middle of the pipe 100, and the upper part of this auxiliary tank is connected to the relief valve 116 through a pipe 144.

The following embodiments apply the present invention to a scooter, but it is of course also applicable to an axle where the fuel supply path between the fuel tank and the carburetor is lower than the carburetor, such as a go-kart. be.

(Effects of the Invention) As described above, the present invention connects the air venting float type relief valve to a position higher than the fuel tank in the fuel supply route, so that the fuel supply route between the fuel tank and the carburetor is connected to the carburetor. Even when lower, the fuel cock is always filled with fuel, ensuring reliable operation of the fuel cock. Therefore, it is possible to reliably prevent the inconvenience of air entering the fuel cock and causing it to malfunction.

[Brief explanation of drawings]

Figure 1 is a side view of one embodiment of the present invention, Figure 2.3.4 is a front view, partially sectional left side view and right side view of an automatic fuel cock, and Figure 5.6 is a side view of an automatic fuel cock. In the figure, a sectional view taken along the line V-v and a sectional view taken along the line Vl-VI, and FIG. 7 is a sectional view of the relief valve. 8.9.10 are side views showing other embodiments. 48...Carburizer, 54...Fuel tank, 100.130,132,136...Pipe, 116
...Relief valve.

Claims (1)

[Scope of Claims] A vehicle comprising a carburetor located below a fuel tank, and a fuel supply path passing below the carburetor and supplying fuel from the fuel tank to the carburetor, comprising: An automatic fuel cock is provided at a position above the carburetor and opens a fuel supply route using negative intake pressure of the engine, and a float type relief valve for air venting is connected to a position higher than the fuel cock in the fuel supply route. A vehicle fuel supply device comprising: