JP4297883B2 - Fuel spill prevention valve device - Google Patents

Description

  The present invention is attached to a fuel tank of an automobile, for example, and communicates the inside of the fuel tank to the atmosphere at normal times, thereby escaping the fuel vapor to the outside of the fuel tank to prevent the pressure inside the fuel tank from rising and the automobile toppling over. The present invention relates to a fuel outflow prevention valve device for preventing fuel from flowing out of a fuel tank when the vehicle is accelerated, suddenly accelerated, or suddenly turned.

In the fuel outflow prevention valve device described above, it is desirable to increase the cross-sectional area of the orifice in order to quickly release the fuel vapor to the outside of the fuel tank and prevent the pressure inside the fuel tank from increasing.
However, if the cross-sectional area of the orifice is increased, the contact area between the valve body that opens and closes the orifice and the valve seat increases, so that the valve body sticks to the valve seat.

When the pressure of the fuel vapor in the fuel tank rises with the valve body sticking to the valve seat in this way, the valve body is pressed against the valve seat by the pressure of the fuel vapor, and the valve body moves against this force. Therefore, it is difficult to open the orifice, so in general, by reducing the diameter of the orifice and reducing the contact area between the valve body and the valve seat, the force with which the valve body sticks to the valve seat is reduced. ing.
However, if the diameter of the orifice is reduced, the fuel vapor cannot be quickly released out of the fuel tank.

Therefore, the first valve body that opens and closes the large-diameter first orifice provided in the housing is connected to the second valve that has a smaller diameter than the first orifice that communicates with the first orifice while the first valve body closes the first orifice. By providing an orifice and a second valve body for opening and closing the second orifice in the first valve body, the first and second valve bodies close the first and second orifices, and the first valve body is the valve seat. Even if the pressure of the fuel vapor in the fuel tank rises while sticking to the fuel tank, the second valve body opens the second orifice so that the first valve body opens the first orifice and the fuel vapor is supplied to the fuel tank. There has been proposed a fuel spill prevention valve device that can quickly escape to the outside.
JP-A-4-236870

  However, the conventional fuel outflow prevention valve device described above has a structure in which the second valve body is accommodated in the first valve body, and the first and second orifices are closed from a state in which the first and second orifices are opened. In order to open the first and second orifices in a state in which the first and second orifices are closed, and the second valve body is moved to open and close the first orifice. Two movement strokes for opening and closing the orifice are required, and the entire valve body movement stroke is obtained by adding both movement strokes.

Therefore, since the length of the first and second valve bodies in the moving direction is increased, the first and second valve bodies are increased in size and weight, and the first and second valve bodies open and close the first and second orifices. Is inferior.
And since the 1st valve body and the 2nd valve body are superposing | polymerizing at the normal time, a valve head and a valve seat will be worn out by the friction by vibration, and it becomes impossible to maintain sealing performance for a long period of time.
Further, since the valve body moving stroke for opening and closing the first and second orifices becomes long, the full tank liquid level of the fuel tank cannot be raised, the dead space becomes large, and more fuel is supplied to the fuel tank. I could not refuel.
Furthermore, since the second valve body is accommodated in the first valve body, the structure becomes complicated and a malfunction may occur.

  The present invention has been made in order to eliminate the above-described disadvantages, and can prevent sticking of each valve body, maintain sealing performance for a long time, and reduce the dimension of each valve body in the moving direction. The present invention provides a fuel outflow prevention valve device that can be reduced in size and weight, can supply a larger amount of fuel into a fuel tank, and is less likely to cause malfunctions with a simple structure.

The present invention is as follows.
(1) A plurality of cavities that communicate with a flow passage that communicates with the outside of the fuel tank via an orifice are provided in parallel, and each of the cavities includes an opening that communicates with the interior of the fuel tank; In the fuel outflow prevention valve device having a plurality of valve bodies that move in the respective hollow portions to open and close the corresponding orifices, a cross-sectional area of one of the plurality of orifices is made smaller than a cross-sectional area of the other orifice. The valve body that opens and closes the orifice having a small cross-sectional area has a small cross-sectional area before the corresponding orifice is opened by the other valve body dropping by its own weight against the sticking force. The orifice is opened to prevent the other valve body from sticking .
(2) In the fuel outflow prevention valve device described in (1), the plurality of cavities are positioned at the same height.

According to the present invention, since the cross-sectional area of one of the plurality of orifices is made smaller than the cross-sectional area of the other orifice, the valve body that opens and closes the orifice having a small cross-sectional area has a weak sticking force to the valve seat. Is easier to open than other orifices.
Therefore, the valve body that opens and closes the orifice with the small cross-sectional area opens the orifice with the small cross-sectional area before the other valve body opens the corresponding orifice against the sticking force. It is possible to prevent the pressure in the fuel tank from increasing by opening the valve.
Since the plurality of cavities are positioned at the same height, the dimension of the plurality of valve bodies in the moving direction can be reduced, the size and weight can be reduced, and the dead space is reduced and the fuel tank is further reduced. A lot of fuel can be refueled.

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

1 is a sectional view showing a fuel spill prevention valve device according to an embodiment of the present invention, FIG. 2 is an external perspective view of the fuel spill prevention valve device shown in FIG. 1, and FIGS. 3 and 4 are FIGS. It is operation | movement explanatory drawing of the fuel outflow prevention valve apparatus shown in FIG.
3 shows a state in which the first orifice is closed by the first valve body and the second orifice is closed by the second valve body, and FIG. 4 shows only the first orifice in the first valve body. The closed state is shown.

  In these drawings, the housing indicated by 1 is made of a polyacetal resin that is rich in rigidity and molded with a polyacetal resin that can be molded with high dimensional accuracy, and a polyacetal resin that is attached to the housing body 2 so as to close an open portion. The cap 7 is formed.

  The housing body 2 includes a plurality of locking claws 2n positioned at the lower end portion of the outer peripheral surface, a first cavity portion 3A having a first orifice 4A having a circular cross section at the central portion of the upper surface, and a central portion of the upper surface. A second cavity 4B having a circular cross-section second orifice 4B having a smaller cross-sectional area than the first orifice 4A, located at the same height as the first cavity 3A, and communicating with the first cavity 3A; The plurality of openings 5 located in the peripheral wall portion communicate with the first cavity 3A and the second cavity 3B, and communicate with the first cavity 3A via the first orifice 4A and the second cavity 3B. And a flow passage 6 communicating with the second orifice 4B.

  Further, the cap 7 corresponds to the plurality of locking claws 2n, and a plurality of engagement holes 7h for the locking claw 2n to enter and engage with the cap 7 and an opening communicating with the first cavity 3A. Corresponding to the position of the first through hole 7a as the opening, the second through hole 7b as the opening communicating with the second cavity 3B, and the first cavity 3A, the first coil spring 21A to be described later is positioned first. An annular recess 8A and a second annular recess 8B for positioning a second coil spring 21B described later are provided corresponding to the position of the second cavity 3B.

The first valve element molded with polyacetal resin 11A moves in the axial direction of the first cavity 3A in the first cavity 3A to open and close the first orifice 4A, and has a first orifice on the upper surface. A valve head 12A for opening and closing 4A is provided, and a recess 13A for accommodating the first coil spring 21A is formed on the lower surface.
The second valve body formed of polyacetal resin shown by 11B moves in the axial direction of the second cavity 3B in the second cavity 3B to open and close the second orifice 4B, and has a second orifice on the upper surface. A valve head 12B that opens and closes 4B is provided, and a recess 13B that accommodates the second coil spring 21B is formed on the lower surface.
The first valve body 11A and the second valve body 11B have the same shape and the same weight except for the valve heads 12A and 12B.

The first coil spring as the first urging member indicated by 21A cannot move the first valve body 11A against its own weight to close the first orifice 4A. The biasing force is set so that the first orifice 4A can be closed by moving in cooperation with the buoyancy.
The second coil spring as the second urging member indicated by 21B cannot move the second valve body 11B against its own weight to close the second orifice 4B. The biasing force is set so that the second orifice 4B can be closed by moving in cooperation with the buoyancy.

The first cushion as a first cushioning material indicated by 31A is for preventing noise from being generated when the first valve body 11A abuts against the cap 7, and is provided on the lower surface of the first valve body 11A. It is attached.
A second cushion as a second cushioning material indicated by 31B is for preventing noise from being generated when the second valve body 11B abuts against the cap 7, and is provided on the lower surface of the second valve body 11B. It is attached.

Next, the operation will be described.
First, as shown in FIG. 1, in a normal state in which the fuel outflow prevention valve device is attached to the fuel tank, the first valve body 11A descends by its own weight against the urging force of the first coil spring 21A, and the valve head 12A Opens the first orifice 4A, the second valve body 11B descends by its own weight against the urging force of the second coil spring 21B, and the valve head 12B opens the second orifice 4B.
Accordingly, the fuel vapor generated in the fuel tank, that is, gasoline vapor, flows through the opening 5 or the first and second through holes 7a and 7b, the first and second cavities 3A and 3B, and the first and second orifices 4A and 4B. , It is discharged via the flow passage 6, and an increase in the pressure in the fuel tank can be prevented.

Then, the vehicle is suddenly accelerated or the steering wheel is suddenly turned to generate a large inertial force, and the inertial force causes gasoline to flow from the opening 5 and the first and second through holes 7a and 7b to the first and second cavities 3A and 3B. When the air flows into the first and second valve bodies 11A and 11B, the first and second valve bodies 11A and 11B tend to float (raise) by buoyancy, but the specific gravity of the first and second valve bodies 11A and 11B is greater than that of gasoline. Since the two valve bodies 11A and 11B cannot float by themselves and float with the aid of the urging force of the corresponding first or second coil springs 21A and 21B, as shown in FIG. 3, the valve heads 12A and 12B The first and second orifices 4A and 4B are closed.
Therefore, it is possible to prevent gasoline from flowing out of the fuel tank.

When the automobile returns to a normal state and gasoline in the housing 1 returns from the opening 5 and the first and second through holes 7a and 7b into the fuel tank, the first and second valve bodies 11A and 11B are under their own weight. The first or second coil springs 21A and 21B are compressed and lowered to open the first and second orifices 4A and 4B as shown in FIG.
When the first and second valve bodies 11A and 11B thus open the first and second orifices 4A and 4B as described above, the diameter of the second orifice 4B is smaller than the diameter of the first orifice 4A. That is, the area where the valve head 12B contacts the housing body 2 which is the valve seat is smaller than the valve head 12A, and the force with which the valve head 12B sticks to the housing body 2 is weaker than the force with which the valve head 12A sticks. Thus, the 2nd valve body 11B can open | release the 2nd orifice 4B rapidly, can release gasoline vapor | steam outside a fuel tank, and can prevent the raise in the pressure in a fuel tank.

And as shown in FIG. 1, since the 1st valve body 11A also opens the 1st orifice 4A, the raise of the pressure in a fuel tank can be prevented more rapidly.
Thus, when the first and second valve bodies 11A, 11B are lowered to open the first and second orifices 4A, 4B, the first and second valve bodies 11A, 11B are the first or second cushion 31A, Since it collides with the cap 7 via 31B, a colliding sound, that is, noise is not generated.

  As described above, according to one embodiment of the present invention, the sectional area of the second orifice 4B is made smaller than the sectional area of the first orifice 4A, and the diameter of the second orifice 4B is made larger than the diameter of the first orifice 4A. Since it is made smaller, the sticking force to the housing body 2 that is the valve seat of the second valve body 11B is weak, the second valve body 11B can easily open the second orifice 4B, and the housing body 2 of the second valve body 11B can be opened. Can prevent the first valve element 11A from sticking to the housing main body 2, and can prevent gasoline vapor from quickly escaping out of the fuel tank to prevent the pressure inside the fuel tank from rising. Is obtained.

Since the first and second valve bodies 11A and 11B are separated from the housing body 2 which is a valve seat at normal times, the valve heads 12A and 12B and the valve seat are not worn by vibration, and the sealing performance is maintained for a long time. Can be held.
Moreover, since the valve body moving strokes of the first and second valve bodies 11A and 11B are shortened by positioning the first and second cavities 3A and 3B in parallel at the same height, the first and second valves The dimensions of the bodies 11A and 11B in the moving direction can be reduced, the size and weight can be reduced, and the first and second valve bodies 11A and 11B can respond to opening and closing the first and second orifices 4A and 4B. As it improves, the dead space is reduced and more fuel can be supplied into the fuel tank.

Furthermore, since the first and second cavities 3A and 3B are positioned in parallel at the same height, the structure becomes simple and malfunctions are less likely to occur.
In addition, the first or second cushion 31A, 31B is disposed between the cap 7 and the first and second valve bodies 11A, 11B, and the first and second valve bodies 11A, 11B are connected to the first or second valve body 11A, 11B. Since the cap 7 is abutted via the cushions 31A and 31B, a collision noise, that is, noise is not generated.

In the above-described embodiment, the urging force of the first and second coil springs 21A and 21B moves the first or second valve body 11A and 11B in cooperation with the buoyancy to move the first or second orifice 4A, Since 4B can be closed, gasoline can be prevented from flowing out of the fuel tank even when the automobile falls.
Further, although the first and second cushions 31A and 31B are attached to the lower surfaces of the first or second valve bodies 11A and 11B, they may be attached to the bottoms of the first and second annular recesses 8A and 8B.
Furthermore, although two hollow portions 3A and 3B are provided in the housing main body 2 and the respective valve bodies 11A and 11B are provided, the valve body may be provided by providing three or more hollow portions in the housing.
In this case, the weights of the plurality of valve bodies may be the same, and one of the orifices may be made smaller than the sectional area of the other orifice, or the sectional areas of the plurality of orifices may be different.
The fuel may be light oil or the like in addition to gasoline.

It is sectional drawing which shows the fuel outflow prevention valve apparatus which is one Example of this invention. It is an external appearance perspective view of the fuel outflow prevention valve apparatus shown in FIG. It is operation | movement explanatory drawing of the fuel outflow prevention valve apparatus shown in FIG. It is operation | movement explanatory drawing of the fuel outflow prevention valve apparatus shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Housing 2 Housing main body 2n Locking claw 3A 1st cavity 3B 2nd cavity 4A 1st orifice 4B 2nd orifice 5 Opening 6 Flow path 7 Cap 7h Engagement hole 7a 1st through-hole 7b 2nd through-hole 8A 1st 1 annular recess 8B second annular recess 11A first valve body 11B second valve body 12A valve head 12B valve head 13A recess 13B recess 21A first coil spring (first biasing member)
21B Second coil spring (second biasing member)
31A First cushion (first cushioning material)
31B Second cushion (second cushioning material)

Claims (2)

A plurality of cavities communicating in parallel with a flow passage that leads to the outside of the fuel tank via an orifice, and a housing provided with an opening communicating with the interior of the fuel tank in each of the cavities;
In the fuel outflow prevention valve device comprising a plurality of valve bodies that move in the respective hollow portions to open and close the corresponding orifices,
The cross-sectional area of one of the plurality of orifices is smaller than the cross-sectional area of the other orifice;
The valve body that opens and closes the orifice having a small cross-sectional area is opened before the corresponding orifice is opened by the other valve body dropping by its own weight against the sticking force. To prevent sticking of the other valve body . The fuel spill prevention valve device according to claim 1,
The plurality of cavities are located at the same height,
The fuel outflow prevention valve apparatus characterized by the above-mentioned.

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