JPH09317586A - Liquid cut-off valve device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve are-opening valve characteristic of a liquid cut-off valve device, and rapidly solve sticking phenomenon of a float valve when cut-off of liquid is eliminated. SOLUTION: A device is provided with a diaphragm 12 (a pressure corresponding means) having a valve seat 11 which is arranged between the inner part of a fuel tank 101 (sealing container) and a discharge passage, capable of movement in the axial direction according to a pressure different between the fuel tank 101 inner part and the discharge passage 10, and provided with a passage 11a (vent hole) for circulating a fuel vapor G, a float 6 for closing a valve element part 6a by closing the passage 11a by movement in the axial direction, a spring 7 (an energizing means) for energizing the float 6 in the valve closing direction, and a spring retainer 8 (a restricting means) for stopping energization of the spring 7 to the float 6 of a valve closing condition, and for specifying the movement distance of the spring 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid shut-off valve device provided in, for example, a fuel tank of a vehicle or the like, and discharges a gas such as a fuel vapor from a discharge path connected to the valve. The present invention relates to a liquid shut-off valve device which functions so as not to leak the liquid into the discharge path.

[0002]

2. Description of the Related Art A conventional liquid cutoff valve device of this kind (fu
As the L-cutoff valve), there is one that can be attached to a fuel tank 101 of a vehicle as shown in FIG. 4, for example.

That is, the liquid shut-off valve device 102 is provided at an upper portion of the fuel tank 101 and discharges a fuel vapor G101 generated inside the fuel tank 101 to a discharge path 103.

[0004] The discharged fuel vapor G
A canister 104 or the like that absorbs the fuel gas 101 is provided as needed to prevent the fuel vapor G101 from being directly released into the atmosphere.

Further, the liquid shutoff valve device 102 discharges the fuel L101 when the water level of the fuel L101 rises or the vehicle leans or falls due to the shaking of the vehicle.
It also has a liquid blocking function to prevent leakage from the 03.

FIG. 5 is a sectional view showing the basic structure of the liquid cutoff valve device 102 and its operation. FIG.
5A shows a state in which the liquid cutoff valve device 102 does not exhibit the liquid cutoff function and is capable of discharging the fuel vapor G101, FIG.
(B) is a diagram of a valve closed state in which the liquid cutoff function is working.

In both figures, 110 is a case part,
The inside is a float chamber 110a that accommodates the float 111. The float 111 generates buoyancy by the fuel L101 flowing into the float chamber 110a from the communication hole 112, and moves upward in the state of FIG. Also 11
Reference numeral 3 denotes a spring which biases the float 111 with a predetermined force in the valve closing direction to adjust the buoyancy and also functions as a biasing means for moving the float 111 in the valve closing direction at the time of rolling over.

[0008] Above the float 111, a valve body 111a is provided.
The valve seat portion 110b corresponding to the valve element 111a is provided above the float chamber 110a, and the discharge path 103 is connected to the valve seat portion 110b.

Therefore, the state shown in FIG.
The fuel L101 flows into 10a, the float 111 moves upward, the valve portion 105 including the valve body 111a and the valve seat portion 110b is closed, and the discharge path 103 is shut off.

The fuel L10 in the float chamber 110a
As the liquid surface water level of No. 1 lowers, the float 111 also moves downward, and the discharge route 103 returns to the normal state in which it communicates with the fuel tank 101 (state of FIG. 5A).

In recent years, in such a liquid shutoff valve device 102, there has been a demand for smoother discharge of fuel vapor, and attempts have been made to increase the valve opening area of the valve portion 105.

[0012]

However, in the liquid cutoff valve device 102 having the valve portion 105 having such a large valve opening area, the inclination or the overturned state of the vehicle is eliminated and the fuel L101 is supplied to the float chamber 110a. Even when returning from the fuel tank 101 to the fuel tank 101, if the pressure difference between the pressure inside the fuel tank 101 and the discharge path 104 on the canister 104 side is large (the pressure inside the fuel tank 101 is higher), the float causes the float difference. There is a problem called “sticking phenomenon” in which the upward biasing force generated in 111 and the biasing force of the spring 113 exceed the dead weight of the float 111, and the discharge path remains closed without being opened. .

When this sticking phenomenon occurs, the pressure inside the fuel tank 101 loses its escape area, and the pressure further rises due to a rise in temperature under hot weather or the like, and the fuel tank 101 may be deformed or eventually broken. Was.

Further, this sticking phenomenon is more likely to occur as the urging force in the upward direction increases as the valve opening area increases.
There was also a problem that the valve opening area had to be narrowed down, and as a result, the discharge of fuel vapor could not be made a large flow rate.

The present invention has been made to solve the above-mentioned problems of the prior art, and its object is to improve the reopening valve characteristic of the liquid cutoff valve device, and liquid cutoff is unnecessary. It is an object of the present invention to provide a liquid cutoff valve device that can quickly eliminate the sticking phenomenon of the float valve when the above condition occurs and can achieve a large flow rate of the discharged gas.

[0016]

In order to achieve the above object, in the present invention, liquid vapor from a sealed container containing a liquid is discharged to the outside of the sealed container through a vent hole that is normally open. A venting means for venting to the passage and a closure for closing the vent hole to prevent the liquid from flowing out of the sealed container to the discharge route when the liquid in the sealed container is shaken or the sealed container is tumbled. In the liquid cutoff valve device including the means, the closing means is provided between the inside of the sealed container and the discharge path, and is movable in the axial direction according to the pressure difference between the both, and the liquid from the sealed container. A pressure responsive means having a vent hole for venting the steam, and a valve portion engaging with the vent hole at the axial tip end, and the axial movement causes the vent hole to be closed to close the valve portion. And the float in the valve closing direction Urging means for urging, and restriction means for specifying the moving distance of the urging means for stopping the urging of the float moving in the axial direction in the valve closed state midway. .

According to this, when the liquid in the sealed container is shaken or the sealed container falls, the float moves in the valve closing direction due to the buoyant force of the float and the urging force of the urging means, and the valve portion is operated. Close the vents to prevent liquid from leaking into the drain.

The pressure response means moves in the axial direction together with the float in the valve closed state due to the pressure difference between the inside of the sealed container and the discharge path.

When the float further moves a predetermined distance while the valve is closed, the regulation means specifies the movement distance of the biasing means, so that the biasing means does not bias the float halfway.

In this state, the sealed container is in a normal upright state, and when the vent hole is opened when the liquid level of the liquid in the float chamber is lowered, the vent hole is opened due to the pressure difference between the inside of the sealed container and the discharge path. Even if the valve portion of the float tries to maintain the valve closed state, the float is in the position where it is not biased by the biasing means, so that the valve is easily opened.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the illustrated embodiment.

The liquid shutoff valve device 1 according to the embodiment of the present invention is mounted as a sealed container on the upper portion of a fuel tank 101 of, for example, an automobile as in the case of the prior art, and is in an upright state in a normal state. Although the fuel vapor G or the like as a gas is sometimes discharged from the discharge path connected to the liquid cutoff valve device 1, for example, when the fuel L as a liquid is refueled or when the vehicle shakes and the liquid level of the fuel L as a liquid increases. It functions to prevent the fuel L from leaking to the discharge path when the vehicle rises or the vehicle leans or falls.

FIG. 1 shows a liquid cutoff valve device 1 to which the present invention is applied.
FIG. 3 is a sectional configuration explanatory diagram illustrating a characteristic configuration of FIG. The main configuration of the liquid shut-off valve device 1 will be described with reference to FIG.

A lower body 2 has a float chamber 2a inside, and a flange portion 2d is fluid-tightly attached to a wall surface 101a at an upper portion of the fuel tank 101 via a gasket 3.

An upper body 4 forming an upper portion of the float chamber 2a is hermetically connected to an upper end portion of the lower body 2, and a cap 5 forming a lower end surface of the float chamber 2a is attached to a lower end portion of the lower body 2. ing.

Reference numeral 6 denotes a float accommodated in the float chamber 2a of the lower body 2, and buoyancy is generated by the fuel L flowing into the float chamber 2a through the communication hole 5a and the like, and moves upward in the state shown in this figure. To do. A valve body portion 6a as a valve portion is integrally formed on the upper portion of the float 6. Reference numeral 7 is a spring that adjusts the buoyancy of the float 6 and functions as a biasing means for biasing the float 6 in the valve closing direction even when the posture of the float 6 is inclined or inverted.

Reference numeral 8 is a spring retainer as a means for restricting the spring 7. The lower surface of the flange portion 8a receives the urging force of the spring 7, and the upper surface of the flange portion 8a urges the float 6. The spring retainer 8 has a flange portion 8
It has a shaft portion 8b which is connected to a and which is inserted through the central portion of the cap 5. Further, a stopper portion 8c that restricts the movement of the spring retainer 8 is provided at the end of the shaft portion 8b to limit the distance that the spring retainer 8 can move upward in the drawing.

On the other hand, the upper body 4 is the lower body 2.
A discharge path 10 for discharging the fuel vapor G is provided.

The valve portion V1 functions as a ventilating means or a closing means depending on the opened / closed state thereof, and is provided with a valve seat 11 which comes into contact with the valve body portion 6a of the float 6, and the fuel vapor G is opened in the valve opened state. It is discharged from the passage 11a as a ventilation hole.

The valve seat 11 can reciprocate along the moving direction (axial direction) of the float 6 by a diaphragm 12 (pressure response means) that can move axially due to the pressure difference between the inside of the fuel tank 101 and the discharge passage 10 side. Held in.

The diaphragm 12 is biased toward the upper end 2b of the float chamber 2a by a spring 13 and abuts against the upper surface of the upper end 2b and is stopped. Reference numeral 14 is an annular retainer that connects the diaphragm 12 and the valve seat 11 and receives the biasing force of the spring 13. Then, when the valve portion V1 moves, the end surface 14a of the skirt portion that extends axially upward on the outer peripheral portion of the annular retainer 14 is configured to abut the locking surface 4b formed on the upper body 4.

Next, the operation of the liquid cutoff valve device 1 will be described. The liquid shutoff valve device 1 includes a float valve chamber 2a.
Normal time when the fuel L does not flow into the inside (this normal time means a state in which the vehicle can be used safely, and is used in a sense that includes a slight inclination of the vehicle. The fuel vapor G in the fuel tank 101 is discharged from the float valve chamber 2a to the discharge path 10 from the valve V in the open state (see FIG. 1).

Further, FIG. 2A shows the fuel L at the time of erecting.
FIG. 6 is a diagram showing a state in which the liquid level La of the fuel L inside the fuel tank 101 has risen due to refueling or the excessive inclination of the vehicle.

In this figure, the float 6 floats by its own buoyancy and the urging force of the spring 7, and the valve body portion 6a abuts the valve seat 11 to close the valve portion V1. In this state, the fuel L does not leak to the discharge path 10, but of course the air existing in the upper space of the fuel tank 101 and the gas such as the fuel vapor G are also shielded, which is unsatisfactory during refueling. It is also possible to prevent the fuel tank 101 from being filled with more fuel L by operating the auto stop function of the illustrated fuel gun. However, this Figure 2
In the state of (a), the fuel vapor G inside the fuel tank 101
Shows that the pressure is not increased, and the urging force of the spring 13 exceeds the force of pushing up the diaphragm 12.

FIG. 2B shows the liquid level La of the fuel L when it is upright.
FIG. 3 is a diagram showing an initial stage state in which the pressure of fuel vapor G inside the fuel tank 101 has risen, and FIG. When the pressure of the fuel vapor G increases, the force that pushes up the diaphragm 12 increases due to the pressure. When the urging force of the spring 13 is exceeded, the diaphragm 12 moves upward together with the valve seat 11.

The float 6 is shown in FIG.
Although the valve seat 11 is moving upward in the closed state as the valve seat 11 is moved, the condition of whether to move or stop at that position to open the valve body 6a depends on the float depending on the position of the liquid level La. 6 and the urging force of the spring 13 and the pressure difference between the inside of the fuel tank 101 and the discharge path 10 side.

The urging force of the spring 13 is caused by the spring retainer 8 whose movement distance is specified by the stopper portion 8
Above the position where c is in contact with the cap 5, the float 6 is restricted from acting. Therefore, the fuel vapor G
The pressure on the diaphragm rises further and the position of the diaphragm 12 is changed to the position shown in FIG.
When moving above the position of (b), the biasing force of the spring 7 does not act on the float 6, and the valve body portion 6a easily opens.

When the valve body 6a opens, the pressure of the fuel vapor G drops and the liquid cutoff valve device 1 returns to the state of FIG. 2 (a).

Next, the operation of the liquid cutoff valve device 1 when the fuel tank 101 is inclined will be described with reference to FIG.
It should be noted that since the same operation is performed even in a fallen state, only the inclined state will be described as a representative.

FIG. 3A shows a normal upright state. FIG.
3B is a state in which the fuel tank 10 is tilted counterclockwise by 45 degrees from FIG. 3A, and FIG. 3C is the state shown in FIG. 3B.
1 the state where the pressure inside has risen, FIG. 3 (d) is FIG. 3 (c)
Represents the state in which the tilted state of FIG. L is the fuel, and La is the liquid level of the fuel L.

In FIG. 3 (b), the liquid surface La rises due to the inclination, the float 6 floats, and the valve body 6a is closed. Here, the pressure of the fuel vapor G is low, and the diaphragm 1
2 has not moved.

When the pressure of the fuel vapor G increases in FIG. 3 (c), the diaphragm 12 operates and the valve seat 11 provided integrally with the diaphragm 12 strokes upward. The float 6 strokes upward together with the valve seat 11 in the valve closed state.

However, the amount of movement of the diaphragm 12 is until the end surface 14a of the annular retainer 14 comes into contact with the locking surface 4b formed on the upper body 4, and further movement is restricted, so a large pressure is applied. Even if the pressure is applied, only the diaphragm 12 and the valve seat 11 do not stroke to open the valve body portion 6a.

Here, the urging force of the spring 7 urges the float 6 up to the position where the valve body portion 6a is closed, but further urging force is not regulated by the spring retainer 8, so the float 7 is not regulated. 6 is pressed against the valve seat 11 by the buoyancy force and the pressure of the fuel vapor G, and moves by the force.

In FIG. 3D, when the inclined state of FIG. 3C is restored to the upright state, the liquid level La drops and the buoyancy of the float 6 also disappears. At the time of this return,
Even when the pressure of the fuel vapor G is high as in FIG. 3C, the float 6 is not affected by both the buoyancy force and the biasing force of the spring 7, and thus the valve body portion 6a is easily opened. The state in which is stuck to the valve seat 11 is eliminated.

[0046]

According to the present invention described above, in the liquid shutoff valve device adopting the float system,
It becomes possible to quickly eliminate the valve reopening characteristic of the valve in the state where the liquid shutoff is not necessary, that is, the sticking phenomenon of the valve portion.

Since the sticking phenomenon can be eliminated quickly, the opening area of the valve can be increased to increase the gas discharge amount.

[Brief description of drawings]

FIG. 1 is an explanatory cross-sectional configuration diagram of a liquid cutoff valve device according to an embodiment of the present invention.

FIG. 2 is a view for explaining the operation of the liquid shut-off valve device of the present invention in an upright state.

FIG. 3 is a view for explaining the operation of the liquid cutoff valve device of the present invention in a tilted state.

FIG. 4 is a diagram showing an example of use of a conventional liquid shut-off valve device.

FIG. 5 is a view of a conventional liquid cutoff valve device.

[Explanation of symbols]

 1 Liquid Cutoff Valve Device 2 Lower Body 2a Float Chamber 2b Upper End 2d Flange Part 3 Gasket 4 Upper Body 4b Locking Surface 5 Cap 5a Communication Hole 6 Float 6a Valve Body 7 Spring 8 Spring Retainer (Regulating Means) 8a Flange 8b Shaft part 8c Stopper part 10 Discharge route 11 Valve seat 11a Passage (ventilation hole) 12 Diaphragm 13 Spring 14 Annular retainer 14a Skirt end face 101 Fuel tank 101a Wall surface G Fuel vapor V1 valve L Fuel La Liquid level

Claims (1)

[Claims] 1. A venting means for venting liquid vapor from a liquid-tight sealed container to a discharge path outside the hermetically sealed container through a normally open vent, and the liquid in the hermetically sealed container is shaken. , Or a closing means for closing the vent hole to prevent the liquid from flowing out of the sealed container to the discharge path when the sealed container is tumbled, A pressure response means provided between the inside of the container and the discharge path, movable in the axial direction according to the pressure difference between the two, and having a vent hole for venting liquid vapor from the sealed container; and the vent hole. A valve part to be engaged is provided at the tip part in the axial direction,
A float that closes the vent hole by moving in the axial direction to close the valve portion, a biasing means that biases the float in the valve closing direction, and a biasing force to the float that moves axially in the closed state. A liquid cutoff valve device comprising: a restriction unit that specifies a moving distance of the urging unit for stopping the operation of the liquid cutoff valve.