JPH04237865A - Fuel feeder for vehicle - Google Patents

Abstract

PURPOSE:To interrupt a fuel supply from a fuel tank to a carburetor at time of nontraveling of a vehicle, and simultaneously isolating a tank breather passage of the fuel tank and an air vent passage of the carburetor both from the atmosphere. CONSTITUTION:An auto cock 32 installed in a fuel feed passage L1 is connected to an intake manifold 33 via a vacuum passage L2 with a selector cock 29, thereby controlling a fuel supply from a fuel tank 25 to a carburetor 28. A tank breather passage L4 of the fuel tank 25 and an air vent passage L5 of the carburetor 28 both are connected to the selector cock 29, and at time of nondriving of a vehicle, the tank breather passage L4 and the air vent passage L5 both are isolated from an atmospheric opening passage L6, through which a leak of fuel vapor is kept back.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention enables the switching cock to control the fuel supply from the fuel tank to the engine to open and close the switching cock, thereby allowing the tank breather passage of the fuel tank equipped with the switching cock to be opened and closed when the vehicle is running. The present invention relates to a fuel supply system for a vehicle that is open to the atmosphere and closed when the vehicle is not running.

0002

2. Description of the Related Art Conventionally, as a fuel supply system for such a vehicle, one described in Japanese Utility Model Publication No. 18698/1983 is known.

[0003] The above fuel supply device has a tank breather passage connected to a switching cock provided between the fuel tank and the carburetor, and by opening the switching cock while the vehicle is running, fuel is supplied to the carburetor. The tank breather passage is opened to the atmosphere at the same time, and by closing the switching cock when the vehicle is not running, the fuel supply is cut off and the tank breather passage is closed at the same time. Thereby, it is possible to prevent fuel from flowing out from the fuel supply passage or fuel vapor from flowing out from the tank breather passage of the fuel tank.

0004

However, the conventional fuel supply system described above only closes the fuel supply passage and the tank breather passage, and the air vent passage of the carburetor remains open to the atmosphere.

The present invention has been made in view of the above-mentioned circumstances, and it is an object of the present invention to provide a fuel supply system for a vehicle that can reliably prevent the outflow of fuel or fuel vapor simply by closing the cock.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a method for controlling fuel supply by opening and closing a switching cock that controls fuel supply from a fuel tank to an engine. In a fuel supply system for a vehicle in which a tank breather passage of a tank is opened to the atmosphere when the vehicle is running and closed when the vehicle is not running, an air vent passage of the carburetor is connected to the switching cock, and this air vent passage is connected to the air vent passage when the vehicle is not running. The first feature is that it opens when the vehicle is running and closes when the vehicle is not running.

In addition to the above-mentioned first feature, the present invention also provides that the switching cock opens and closes the negative pressure passage of an autocock interposed between the fuel tank and the engine, thereby controlling the flow from the fuel tank to the engine. The second feature is to control fuel supply.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a side view of the folding motorcycle when it is assembled, and FIG. 2 is a side view of the folding motorcycle. The vehicle body frame includes a front frame 1 that supports a driving system, and a rear frame 2 that supports a drive system including rear wheels Wr.

As is clear from FIG. 3,
The front frame 1 includes a pair of left and right band-shaped side plates 3 facing each other with a predetermined interval, and a handle post 4 vertically passes through the front ends of the side plates 3. That is, the handle post 4 is supported by a head pipe 5 fixed between the side plates 3 so as to be rotatable left and right, and has a lower shaft 7 at the bottom that pivotally supports the front wheel Wf via a front fork 6, and this lower shaft 7. The upper shaft 11 is pivotally supported at the upper end via a folding pin 8 so as to be swingable back and forth, and the upper shaft 11 supports a steering handle 10 via a steering shaft 9. At the upper end of a bracket 12 fixed to the front end of the side plate 3, a connecting arm 14 extending rearward of the vehicle body via a folding pin 13 disposed coaxially with the folding pin 8 is supported so as to be swingable back and forth. A locking means L is provided between the longitudinally intermediate portion of the arm 14 and a bracket 15 provided on the upper surface of the side plate 3, which can be freely engaged and detached by a pin connection. Therefore, by operating the locking means L, it is possible to hold the upper shaft 11 of the handle post 4 in the assembled position (see FIG. 1) in which it stands up on the lower shaft 7, and the action of the locking means L also By releasing the upper shaft 11, the upper shaft 11 is swung backwards around the folding pin 8, and at the same time, the connecting arm 14 is swung backwards around the folding pin 13 together with the upper shaft 11, and the steering shaft 9 is moved forward. It can be stored in a folded position along the top surface of the frame 1 (see FIG. 2). At this time, by folding the left and right steering handles 10 downward around the shaft 16 (the position where the steering handles 10 are along both left and right sides of the steering shaft 9), the entire width can be kept within the width of the front frame 1. can.

The rear frame 2 includes a pair of left and right parallelogram-shaped side plates 17 facing each other with a predetermined interval, and a pair of front and rear rollers 18 and 19 are supported outwardly on the upper side of each side plate 17. . On the other hand, on the inner surfaces of the left and right side plates 3 of the front frame 1, there are guide grooves 31 extending in the front-rear direction,
32 is formed, and the front and rear rollers 18 and 19 are rotatably engaged with the guide grooves 31 and 32, and the rear end of the connecting arm 14 and the front end of the rear frame 2 are connected via a link 20. Ru. As a result, when the steering shaft 9 of the handle post 4 is swung rearward to fold it, the rear frame 2 is moved to the link 20.
When the steering shaft 9 is raised, the rear frame 2, which is pressed by the link 20, retreats and moves to the assembly position (see Fig. 1). do. At this time, in the folded position and the assembled position, the pair of front and rear protrusions 171 172 provided on the outer surface of the side plate 17 of the rear frame are connected to the recesses 33 and 34 formed in the side plate 3 of the front frame 1.
By fitting the front frame 1 and the rear frame 2 to each other, vertical play between the front frame 1 and the rear frame 2 is prevented at both positions.

Seat 2 provided at the rear of the vehicle body frame
1 is connected at its rear end to the front frame 1 via a link 22, and at the same time its front end is connected to the rear frame 2 via a link 23. Therefore, when the rear frame 2 is in the assembled position retracted with respect to the front frame 1, both the links 22 and 23 are erected and the seat 21 is raised to the usable position, and the rear frame 2 is in the assembled position with respect to the front frame 1. On the other hand, when the seat is in the advanced folding position, both the links 22 and 23 are brought down and the seat 21 is stored in the lowered position.

A power unit P that integrates a single-cylinder two-stroke engine E and a transmission (not shown) is suspended from the front part of the rear frame 2, and a rear wheel Wr that is pivotally supported at the rear end of the rear frame 2 is supported. is connected to the power unit P via a chain 24.

A fuel tank 25 is located at the top of the rear frame 2.
and an oil tank 26 are provided at the front and rear, and these fuel tank 25 and oil tank 26 move along the space formed between the left and right side plates 3 of the front frame 1 when the rear frame 2 slides. An air cleaner 27 and a carburetor 2 are installed between the fuel tank 25 and the power unit P.
8, and a switching cock 29 which will be described later and which opens and closes in conjunction with the expansion and contraction of both frames 1 and 2. Further, an exhaust pipe 30 extending rearward from the engine E is installed along the lower part of the power unit P and covered with an exhaust pipe cover 54, and the exhaust pipe 30 is further connected to a muffler 31 having a tail pipe 311. The switching cock 29 is provided with an opening/closing lever 291 extending upward, and as the rear frame 2 slides, the lever 291 of the switching cock 29 is opened and closed.
In order to operate the front frame 1, a pair of front and rear engaging portions 35 and 36 are protruded from the lower surface of the side plate 3 of the front frame 1.

As shown in detail in FIGS. 4 and 5, the side plate 17 of the rear frame 2 has an opening 1 extending in the longitudinal direction of the vehicle body.
73, the upper part is bent at a different level than the lower part, and by overlapping the upper part of the side plate 17 with the inside of the side plate 3 of the front frame 1,
The lower surface of the side plate 17 and the side plate 3 of the front frame 1
are arranged so that their surfaces are substantially flush with each other. The switching cock 29 is bolted to two bosses 174 and 175 protruding from the side plate 17 of the rear frame 2, and the upper end of a lever 291 extending upward from the switching cock 29 is attached to the side plate 17 of the rear frame 2. An opening 173 formed in
It comes into contact with the engaging portions 35 and 36 at this point. In addition,
Recesses 37 , 38 are provided in the side plates 3 inside the engaging portions 35 , 36 to avoid interference with the lever 291 . Further, four openings 176 are formed in the center of the side plate 17 of the rear frame 2 to cool the muffler 31 disposed inside the openings 176 and to reduce the weight of the vehicle body.

As shown in FIGS. 6 to 8, the switching cock 29 controls the opening and closing of an autocock 32 installed in the fuel supply passage L1 connecting the fuel tank 25 and the carburetor 28. The negative pressure chamber of the engine E and the intake manifold 33 of the engine E are the negative pressure passage L2,
Communication is possible via port P1, port P2, and negative pressure passage L3. Further, the gas-liquid separator 35 inside the relief valve 34 provided at the upper part of the fuel tank 25 is connected to the port P3 of the switching cock 29 via the tank breather passage L4, and the air vent passage L5 from the carburetor 28 is connected to the switching cock. 29, and both the ports P3 and P4 can communicate with the atmosphere opening passage L6 via the port P5. and,
The relief valve 34 of the gas-liquid separation separator 35 communicates with the clean side of the air cleaner 27 via a relief passage L7.

As shown in FIGS. 8 and 9, a cap 36 covering a fuel supply port and a gas-liquid separator 35 are provided on the upper surface of the fuel tank 25, which is integrally molded from synthetic resin. A pair of tank breather ports 37 and 38 are provided on both left and right sides of the upper surface of the fuel tank 25 in the middle part in the longitudinal direction.
The left port 37 connects to the gas-liquid separator 35 via a breather tube 39 that is curved in a U-shape so as to protrude slightly outward from the right side of the fuel tank 25.
and the right port 38 is connected to the fuel tank 2.
It is connected to the gas-liquid separation separator 35 through a breather tube 40 that protrudes slightly outward from the left side surface of the gas-liquid separator 5. As a result, even if the fuel tank 25 is tilted significantly in the front-rear direction or tilted sideways to the left or right, it is considered that a large amount of internal fuel will not flow into the gas-liquid separator 35.

As is clear from FIG. 10, the gas-liquid separator 35 includes a lower housing 41, an upper housing 42, and a central housing 43 sandwiched between the housings 41, 42.
A first gas-liquid separation chamber 44 and a valve chamber 45 of the relief valve 34 are defined between the upper housing 42 and the center housing 43, and a second gas-liquid separation chamber 46 is defined between the upper housing 42 and the center housing 43. will be accomplished. A pair of ports 47 and 48 to which the breather tubes 39 and 40 are connected are opened at the lower end of the first gas-liquid separation chamber 44, and between the first gas-liquid separation chamber 44 and the second gas-liquid separation chamber 46. A minute through hole 49 is opened. The second gas-liquid separation chamber 46 is connected to the tank breather passage L4 through a port 50 formed in the lower housing 41.
connected to. Therefore, in the unlikely event that the breather tube 3
Even if a small amount of fuel flows into the first gas-liquid separation chamber 44 through the holes 49 and 40, this fuel cannot reach the second gas-liquid separation chamber 46 through the through hole 49, and the fuel is Only steam flows into the second gas-liquid separation chamber 46.

The relief valve 34 provided inside the gas-liquid separator 35 has an annular valve body 53 mounted on the upper surface of a spring seat 52 which is urged upward by a valve spring 51.
When the internal pressure of the fuel tank 25 rises above a predetermined value, the valve element 53 opens against the valve spring 51, and the second gas-liquid separation chamber 46 and the valve chamber 45 are separated through the through hole 54. communicate. This valve chamber 45 is connected to the relief passage L7 via a port 55 formed in the lower housing 41. The upper ends of the tank breather passage L4 and the relief passage L7 are disposed inside a groove 251 formed in the vertical direction on the side surface of the fuel tank 25.

As is clear from FIGS. 8 and 11, the autocock 32 disposed below the fuel tank 25 includes a main body housing 56 and a cover plate 57, and the main body housing 56 includes a joint member 70 and a filter 58. are coaxially tightened together by a nut 59. This autocock 32 is attached to the fuel tank 25 by coupling a bracket 253 provided on the fuel tank 25 with a bracket 701 provided on the joint member 70. Filter 5
8 is a cylindrical member whose end on the autocock 32 side is open, and a mesh 581 is stretched over a plurality of openings formed in the middle part of the cylindrical member. The tip of the filter 58 protruding from the joint member 70 is inserted into the outlet 252 of the fuel tank 25, and the outlet 252 and the joint member 57 are connected by a tube 60 made of an elastic material.

A disc-shaped diaphragm 61 is disposed between the main body housing 56 and the cover plate 57 of the autocock 32.
The outer periphery of is clamped. An inlet chamber 6 communicating with the fuel tank 25 is provided between the main body housing 56 and the diaphragm 61.
2 and a port 63, an outlet chamber 64 is defined, which communicates with the fuel supply passage L1 through a port 63, and an annular valve body 611 protruding from the center of the diaphragm 61 and a valve seat 561 formed on the main body housing 56 connect the inlet chamber to the fuel supply passage L1. 62 and exit chamber 6
4 is communicated/blocked. On the other hand, a negative pressure chamber 66 is defined between the diaphragm 61 and the cover plate 57 and communicates with the negative pressure passage L2 via a port 65. Negative pressure chamber 6
6 has a spring seat 6 supported on the cover plate 57.
A spring 69 is compressed between the spring seat 68 supported by the diaphragm 61, and the spring 69 causes the valve body 611 of the diaphragm 61 to sit on the valve seat 561.

Next, the operation of the above-described embodiment of the present invention will be explained. When the motorcycle V is in the assembled state shown in FIG. The lever 291 is pushed forward by the rear engaging portion 36, and the switching cock 29 is opened (see FIG. 6). As a result, the negative pressure chamber 66 of the autocock 32 is
5. In order to connect to the intake manifold 33 of the engine E via the negative pressure passage L2, port P1, port P2, and negative pressure passage L3, the intake manifold 3
3, the diaphragm 61 deforms against the spring 69, and the valve body 611 separates from the valve seat 561. As a result, the inlet chamber 62 and the outlet chamber 64 communicate with each other, and the fuel in the fuel tank 25 is transferred from the filter 58 to the autocock 32.
The fuel is further supplied to the carburetor 28 via the port 63 and the fuel supply passage L1. At this time, the ports 50 of the second gas-liquid separation chamber 46 of the gas-liquid separation separator 35 are connected to the tank breather passage L4, port P3, and port P5.
The air vent passage L5 extending from the carburetor 28 communicates with the atmosphere opening passage L6 through ports P4 and P5, and the fuel supply system of the motorcycle V becomes ready to run. .

Furthermore, when the motorcycle V is folded as shown in FIG. 2 to be stored in the trunk of an automobile, the flyer frame 2 slides forward with respect to the front frame 1, so that the side plate of the front frame 1 The lever 291 is pushed rearward by the front engaging portion 35 provided at the front end of the lever 291, and the switching cock 29 is closed (see FIG. 7). As a result, communication between the negative pressure chamber 66 of the autocock 32 and the intake manifold 33 is cut off, and the negative pressure chamber 66 is connected to the port 65, the negative pressure passage L2, the port P1, and the port P3.
, tank breather passage L4, gas-liquid separation separator 35
It communicates with the fuel tank 25 via. As a result, the pressure in the negative pressure chamber 66 of the autocock 32 and the pressure in the outlet chamber 64, that is, the pressure on both the left and right sides of the diaphragm 61, become the same, and the elastic force of the spring 69 pushes the valve body 611 of the diaphragm 61 toward the valve seat. Take a seat at 561. In this case, even if the internal pressure of the fuel tank 25 changes, the pressure acting on both left and right sides of the diaphragm 61 is always the same, so the autocock 32 is kept closed and unnecessary fuel is supplied to the carburetor 28. be prevented from being At the same time, the tank breather passage L4 of the fuel tank 25 and the air vent passage L5 of the carburetor 28 are shut off from the atmosphere opening passage L6 by the switching cock 29, thereby preventing fuel and fuel vapor from leaking to the outside. In addition, switching cock 2
9 is closed, if the internal pressure of the fuel tank 25 rises beyond the specified value due to factors such as a rise in temperature, the valve body 53 of the relief valve 34 moves down against the elastic force of the spring 51, and the fuel tank 25 closes. The pressure of 25 is released to the air cleaner 27 via the relief passage L7.

In this way, the switching cock 29 is automatically opened and closed by the sliding of the flyer frame 2 when the motorcycle V is folded or assembled, which not only saves the effort of operating the switching cock 29, but also prevents the switching cock 29 from being inadvertently opened. This prevents mistakes such as forgetting operations. Moreover, when the motorcycle V is not running, the switching cock 29 is used to switch the tank breather passage L4 to the tank breather passage L4.
Since both the air vent passage L5 of the carburetor 28 and the air vent passage L5 of the carburetor 28 are blocked from the atmosphere opening passage L6, leakage of fuel vapor can be reliably prevented.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-mentioned embodiments, and various small design changes may be made without departing from the scope of the present invention as set forth in the claims. It can be performed.

For example, in the embodiment, the switching cock 29 is opened and closed in conjunction with the folding operation of the vehicle body frame.
It is also possible to directly open and close this switching cock 29 by manual operation.

[0027]

As described above, according to the first feature of the present invention, by closing the cock when the vehicle is not running, the fuel supply from the fuel tank to the engine E is cut off and the breather passage of the fuel tank is closed. will be closed. Furthermore, since the air vent passage of the carburetor is also closed by operating the cock, it is possible to reliably prevent fuel or fuel vapor from flowing out even if the vehicle is placed on its side, for example.

According to the second feature of the present invention, since the fuel supply is controlled by the autocock interposed between the fuel tank and the engine, the autocock is opened only when the engine is running to supply fuel. This makes it possible to more reliably prevent unnecessary outflow of fuel.

[Brief explanation of the drawing]

FIG. 1 is an overall side view of a motorcycle in an assembled state according to an embodiment of the present invention.

[Figure 2] Overall side view of the motorcycle in the folded state

[Figure 3] Cross-sectional view taken along line 3-3 in Figure 1

[Figure 4] Enlarged view of main parts of Figure 1

[Figure 5] Cross-sectional view taken along line 5-5 in Figure 4

[Figure 6] Schematic diagram of the fuel system during driving

[Figure 7] Schematic diagram of the fuel system when not driving

[Figure 8] Overall side view of fuel system

[Fig. 9] View from the 9-direction arrow in Fig. 8

[Figure 10] Cross-sectional view taken along line 10-10 in Figure 8

[Figure 11] Enlarged sectional view of main parts in Figure 8

[Explanation of symbols]

25...Fuel tank 28...Carburetor 29...Switching cock 32...Auto cock E...Engine L2... Negative pressure passage L3... Negative pressure passage L4...Tank breather passage L5...Air vent passage V...Motorcycle (vehicle)

Claims (2)

[Claims] [Claim 1] From the fuel tank (25) to the engine (E
), the tank breather passage (L4) of the fuel tank (25) equipped with this switching cock (29) can be opened and closed by opening and closing the switching cock (29) that controls the fuel supply to
is released to the atmosphere when the vehicle (V) is running, and the vehicle (V)
In a fuel supply system for a vehicle that is closed when the vehicle is not running, a carburetor (28) is connected to the switching cock (29).
A fuel supply system for a vehicle, characterized in that an air vent passage (L5) is connected to the air vent passage (L5), the air vent passage (L5) is opened when the vehicle (V) is running, and is closed when the vehicle (V) is not running. 2. The switching cock (29) opens and closes the negative pressure passages (L2, L3) of the autocock (32) interposed between the fuel tank (25) and the engine (E), thereby switching the fuel tank The fuel supply system for a vehicle according to claim 1, characterized in that the fuel supply system for a vehicle (25) controls fuel supply from the engine (E) to the engine (E).