JP2022111436A - Valve gear - Google Patents

Abstract

To provide a valve gear for effectively preventing an event that fuel entering into a valve chest when a valve is being opened in a state of a high pressure in a valve chest, or remaining is jetted out to a ventilation flow path side together with a gas in the valve chest 2.SOLUTION: A valve gear includes a partition wall 3 partitioning an upper part chamber 1 including a ventilation part 1a to the outside of a fuel tank T and a valve chest 2 formed below the upper part chamber 1, and a valve port part 3a formed therein to be opened/closed by a float body 4 stored in the valve chest 2 in an up-and-down movable manner, the valve chest 2 being formed with an inflow port 2a for fuel, and further includes a check valve 11 provided above the inflow port 2a and below the partition wall 3 for opening itself when a pressure in the valve chest 2 is higher than a pressure in the fuel tank T.SELECTED DRAWING: Figure 2

Description

TECHNICAL FIELD The present invention relates to an improvement in a valve device that is attached to a fuel tank of an automobile, motorcycle, or the like and used to connect the ventilation passage of the fuel tank to the fuel tank.

Patent Document 1 discloses a valve device that is attached to a fuel tank and used to connect a vent flow path to the fuel tank.

However, when the valve device of this type is open and the fuel in the fuel tank fluctuates due to, for example, the vehicle traveling in a slalom, the fuel flows into and out of the valve chamber in which the float valve is housed. is repeated, the valve opening state and the valve closing state are repeated by the float valve, and it is assumed that the valve is opened when the pressure in the valve chamber is higher than the pressure in the fuel tank outside the valve chamber.

In this way, if the valve is opened while the pressure in the valve chamber is high, there is a possibility that the fuel that has entered the valve chamber or the remaining fuel will be ejected to the ventilation passage side together with the gas in the valve chamber. be.

In Patent Document 1, the valve chamber is provided with a relief valve, which opens when the pressure of the gas phase in the fuel tank becomes higher than the pressure of the gas phase in the valve chamber. It does not solve the above situation.

Japanese Patent Application Laid-Open No. 2004-300939

The main problem to be solved by the present invention is to be able to effectively prevent this situation in a valve device of this type.

In order to achieve the above object, according to the present invention, from a first aspect, a fuel tank valve device is formed in an upper chamber provided with a vent to the outside of the fuel tank and below the upper chamber. A valve device comprising: a partition wall separating the valve chamber from the valve chamber;
A fuel inlet is formed in the valve chamber, and a check valve is provided above the inlet and below the partition wall to open when the pressure in the valve chamber becomes higher than the pressure in the fuel tank. I did it.

According to this configuration, when the pressure in the valve chamber is higher than the pressure in the fuel tank outside the valve chamber by a predetermined value or more, the check valve can be opened to reduce the pressure in the valve chamber. Therefore, it is possible to effectively prevent the fuel entering or remaining in the valve chamber from being ejected together with the gas in the valve chamber toward the ventilation passage when the valve is opened with a high pressure.

The check valve is provided with an elastically deformable umbrella-shaped head in close contact with the outer surface of the valve chamber, and a fixing portion formed at the center of the umbrella-shaped head, and the check valve is fixed by the umbrella-shaped head. It is one aspect of the present invention that the ventilation portion formed in the valve chamber is closed at a portion between the portion and the umbrella-shaped head.

Also. The float body is composed of a main body and a main valve body vertically movably interposed between the main body and the partition wall. It is one aspect of the present invention to provide the valve body.

According to the present invention, the check valve can effectively prevent the situation described above.

FIG. 1 is a perspective view of a valve device according to one embodiment of the invention. FIG. 2 is a cross-sectional view taken along the line AA in FIG. 1, in which the valve device is in the open state. FIG. 3 is a cross-sectional perspective configuration view of the main part of the valve device, and the valve device is in a closed state. FIG. 4 is a cross-sectional configuration diagram of the valve device, and the valve device is in a closed state. FIG. 5 is a cross-sectional view of the essential parts of the valve device, in which the valve device is in an intermediate state. FIG. 6 is a perspective view of the upper case that constitutes the valve device, omitting the illustration of the check valve. FIG. 7 is a cross-sectional view taken along the line BB in FIG. 6, and the check valve is in the closed state. FIG. 8 is a cross-sectional view of the main part of the upper case, and the check valve is in the open state.

A typical embodiment of the present invention will be described below with reference to FIGS. 1 to 8. FIG. A fuel tank valve device V according to this embodiment is attached to a fuel tank T of an automobile, a two-wheeled vehicle, or the like, and is used to connect a ventilation passage P of the fuel tank T to the fuel tank T. is.

In this valve device V, a lateral partition wall 3 partitions an upper chamber 1 having a vent 1a to the outside of the fuel tank T and a valve chamber 2 formed below the upper chamber 1. A valve opening 3a is formed to be opened and closed by a float body 4 which is housed in a vertically movable manner.

In the illustrated example, the valve device V is formed by combining a case 8 on the lower side of the main body 7 . A top portion 9a of an upper case 9, which will be described later, serves as the partition wall 3, the upper chamber 1 is formed inside the main body 7 above the partition wall 3, and the inside of the case 8 below the partition wall 3 serves as the valve chamber 2. there is

The main body 7 has a short cylindrical shape with a closed top end and an open bottom end. An outer flange 7a is formed at a substantially middle position in the vertical direction of the main body 7. As shown in FIG.

The side portion 7b of the main body 7 positioned between the upper end of the cylinder of the main body 7 and the outer flange 7a, that is, the side portion of the upper chamber 1, is arranged so that the pipe axis is perpendicular to the central axis of the main body 7. A tubular portion 7c integral with the main body 7 is provided. The tubular portion 7c has an outer end 7d positioned outside the side portion 7b of the main body 7, an inner end 7e positioned inside the side portion 7b of the main body 7, and an intermediate portion integral with the side portion 7b of the main body 7. are making it Both the outer end 7d and the inner end 7e are open. In this embodiment, the tubular portion 7c constitutes the ventilation portion 1a.

In the illustrated example, the vent passage P is connected to the fuel tank T via the valve device V by connecting a tube or the like constituting the vent passage P to the tubular portion 7c. .

A case 8 is formed by combining an upper case 9 and a lower case 10. - 特許庁Both the upper case 9 and the lower case 10 are cylindrical.

The lower end of the cylinder of the upper case 9 is open. On the other hand, at the upper end of the cylinder of the upper case 9, there is formed a ceiling portion 9a which serves as a partition wall 3 having the valve opening portion 3a in the center.

The valve mouth portion 3a is configured as a circular hole penetrating through the partition wall 3 in the vertical direction. A circumferential rib 3b framing the valve opening 3a is formed on the lower surface of the partition wall 3 facing the valve chamber 2 side. Further, in the illustrated example, the valve opening 3a has a configuration in which an annular body 3c is positioned inside thereof. The annular body 3c is positioned within the valve mouth portion 3a by a connecting piece 3d connecting the inner surface of the valve mouth portion 3a and the outer surface of the annular body 3c so that the center axis thereof coincides with the hole axis of the valve mouth portion 3a. It is Three connecting pieces 3d are provided with an interval between adjacent connecting pieces 3d in the direction of circling the hole axis of the valve opening 3a.

In the illustrated example, the upper portion of the upper case 9 is fitted into the main body 7 from the lower end side of the cylinder in the main body 7, and the claw-shaped engaging portion 7f formed in the portion of the main body 7 extending below the outer flange 7a is The upper case 9 and the main body 7 are combined by being inserted into a frame-shaped engaged portion 9b formed on the side portion of the upper case 9 and engaged therewith. In this combined state, the upper chamber 1 is formed between the top portion 9a of the upper case 9, which serves as the partition wall 3, and the upper end of the cylinder of the main body 7. As shown in FIG. Reference numeral 13 in FIG. 2 denotes a seal ring that seals between the inner surface of the main body 7 and the outer surface of the upper case 9 .

The lower case 10 has an open upper end of the cylinder and a supporting portion 10a for the float body 4 at the lower end of the cylinder. In the illustrated example, the lower portion of the upper case 9 is fitted into the lower case 10, and the engagement protrusion 9c formed on the outside of the upper case 9 is inserted into and engaged with the engagement window 10b formed at the lower end of the cylinder of the lower case 10. Thus, the lower case 10 and the upper case 9 are combined (see FIG. 1). In the illustrated example, the space inside the case 8 formed by the lower case 10 and the upper case 9 serves as the valve chamber 2 .

The valve chamber 2 is formed with a fuel inlet 2a. At the same time, above the inlet 2a and below the partition wall 3, there is provided a check valve 11 which opens only when the pressure in the valve chamber 2 becomes higher than the pressure in the fuel tank T outside the valve chamber 2. It is That is, the check valve 11 is a one-way valve that allows airflow from the valve chamber 2 into the fuel tank T outside the valve chamber 2, but does not allow airflow in the opposite direction.

In the illustrated example, a ventilation portion 12 is formed on the side of the upper case 9 and is opened and closed by the check valve 11. Between the ventilation portion 12 and the lower end of the cylinder of the upper case 9 is an inlet 2a. formed.

A cylinder upper end 10 c of the lower case 10 is positioned above the inlet 2 a and below the ventilation section 12 . A gap 14 is formed between the inner surface of the side portion of the lower case 10 and the outer surface of the side portion of the upper case 9 .

The inlet 2 a has a rectangular window shape that penetrates the side of the upper case 9 . A plurality of inflow ports 2a are provided at intervals between adjacent inflow ports 2a in the direction around the cylinder axis of the upper case 9 .

In the illustrated example, the case 8 is configured to have a thickness that fits into a mounting hole Ta that is provided in a penetrating state in the fuel tank T, and the outer diameter of the portion where the outer flange 7a of the main body 7 is formed is the mounting hole Ta. It is configured to a size that does not enter the The valve device V is attached to the fuel tank T by welding the outer flange 7a to the outer surface of the fuel tank T in a state in which the portion below the outer flange 7a is inserted into the fuel tank T through the mounting hole Ta. It's like

In the illustrated example, when the liquid level of the fuel in the fuel tank T reaches the upper end 10c of the cylinder of the lower case 10, the fuel flows into the valve chamber 2 through the inlet 2a. 3a is closed to increase the pressure in the fuel tank T, thereby raising the fuel level in the filler pipe (not shown) and allowing the sensor of the refueling gun inserted in the filler pipe to detect that the tank is full. there is That is, the valve device according to this embodiment functions as a fuel limit vent valve (FLVV).

The float body 4 is composed of a main body portion 5 and a main valve body 6 interposed between the main body portion 5 and the partition wall 3 so as to be vertically movable. A sub valve body 5a is provided for the formed vent hole 6a.

That is, the float body 4 has a mode in which the main valve body 6 is mounted on the main body portion 5 . In such a mounted state, the distance between the main valve body 6 and the lower end of the main body portion 5 is smaller than the distance between the partition wall 3 and the support portion 13a. A gap is formed with the inner surface. As a result, when the float body 4 is lowered with its lower end in contact with the support portion 13a, the gas in the fuel tank T mainly flows into the valve chamber 2a through the inlet 2a and passes through the gap to the valve opening portion 3a. flow into the upper chamber 1 (FIG. 2/valve open state of the valve device).

When the fuel level in the fuel tank T rises and the fuel flows into the valve chamber 2a through the inflow port 2a, the main body 5 rises together with the main valve body 6, and the main valve body 6 is seated on the valve opening 3a. Then, the sub-valve element 5a of the main body 5 is seated in the ventilation hole 6a of the main valve element 6 to close it (Figs. 3 and 4/closed state of the valve device).

When the fuel flows out of the valve chamber 2, the main body 5 descends and the auxiliary valve body 5a of the main body 5 is separated from the vent hole 6a of the main valve body 6, whereby the upper chamber 1 and the valve chamber 2 become the main valve. Communication is established within the range of the air hole 6a of the body 6 (FIG. 5/intermediate state of the valve device), and then the main valve body 6 drops so that the upper chamber 1 and the valve chamber 2 are communicated through the valve opening 3a. It has become.

In the illustrated example, a constant biasing force directed toward the upper chamber 1 is applied to the main body 5 by a compression coil spring 15 interposed between the main body 5 and the support portion 13a.

In the illustrated example, the main valve body 6 has a vent hole 6a in the center and an outer diameter larger than that of the valve opening 3a. A short tubular portion 6b is formed on the lower surface of the main valve body 6 and communicates with the vent hole 6a. The main valve body 6 is made of a material that is easily elastically deformed, such as a plastic elastomer. A sub-valve element 5a formed in the main body portion 5 is adapted to be seated on the lower end of the short cylindrical portion 6b.

A leg portion 6c projecting downward from the lower surface of the main valve body 6 is formed between the outer edge of the main valve body 6 and the short cylindrical portion 6b. A bulging portion 6d that protrudes toward the outer edge of the main valve body 6 is formed at the lower end of the leg portion 6c.

As shown in FIG. 5, the main body 5 includes a plate-like head portion 5b whose plate surface is arranged in the lateral direction, and a cylindrical body portion 5c, which are connected to the lower surface of the head portion 5b and the upper end of the body portion 5c. are connected by a support portion 5d so as to form an interval between them.

A through hole 5e is formed in the center of the head 5b. At the center of the upper end of the body portion 5c, a sub-valve element 5a having a trapezoidal shape and protruding toward the through hole 5e is formed.

The main valve body 6 and the main body portion 5 are combined with the short tubular portion 6b and the leg portion 6c of the main valve body 6 inserted into the through hole 5e of the head portion 5b from above. In this combined state, the sub-valve body 5a is positioned directly below the short cylindrical portion 6b, and the top portion 6e of the bulging portion 6d is positioned closer to the outer edge of the head portion 5b than the edge of the through hole 5e. It's like

In the intermediate state, the main body portion 5 is lowered to a position where the hole edge of the through hole 5e is caught by the bulging portion 6d. , the upper chamber 1 and the valve chamber 2 are communicated with each other within the range of the vent hole 6a of the main valve body 6. As shown in FIG.

The check valve 11 includes an elastically deformable umbrella-shaped head 11a that is in close contact with the outer surface of the valve chamber 2, and a fixing portion 11b formed in the center of the umbrella-shaped head 11a. The head portion 11a closes the ventilation portion 12 formed in the valve chamber 2 at a portion between the fixed portion 11b and the umbrella-shaped head portion 11a.

In the illustrated example, the ventilation part 12 has a configuration in which an annular body 12b is positioned in the center of the through hole 12a. The ring-shaped body 12b is positioned in the through-hole 12a by a connecting piece 12c connecting the inner surface of the through-hole 12a and the outer surface of the ring-shaped body 12b with its center axis aligned with the hole axis of the through hole 12a. . Three connecting pieces 12c are provided with an interval between adjacent connecting pieces 12c in the direction around the hole axis of the through hole 12a. A portion between the adjacent connecting pieces 12c functions as the ventilation portion 12. As shown in FIG. The through hole 12a on the outer surface of the upper case 9 is bordered by an annular flat surface 12d that follows a virtual plane. It functions as a tight valve seat (see FIGS. 1 and 6).

In the illustrated example, the umbrella-shaped head 11a is disc-shaped, and the fixing portion 11b is shaped like a leg protruding from the center of one side of the umbrella-shaped head 11a. The protruding end of the fixing portion 11b is formed in a frusto-conical shape and configured to have an engaging surface 11c facing the umbrella-shaped head portion 11a. The umbrella-shaped head 11a is configured to gradually decrease in thickness as it approaches the outer edge 11d, and has an inclination that approaches the engaging surface 11c side as it approaches the outer edge 11d. . Further, in the center of the check valve 11, there is formed a hollow portion 11e continuing from the opposite side of the fixing portion 11b of the umbrella-shaped head portion 11a toward the protruding end of the fixing portion 11b. 11e is open only on the side of umbrella head 11a.

In the illustrated example, it is possible to insert the fixing portion 11b into the annular body 12b from the outside of the upper case 9 while elastically deforming it, and the engaging surface of the fixing portion 11b extends inside the upper case 9. The check valve 11 is mounted on the upper case 9 by engaging the engaging surface 11c with the annular body due to the elastic return of the fixed portion 11b at the fitted position. In this installed state, the umbrella-shaped head 11a is elastically deformed outward, so that the outer edge 11d side thereof is brought into close contact with the annular flat surface 12d functioning as the valve seat, thereby blocking the ventilation section 12 (FIG. 5). , FIG. 7/closed state of check valve 11).

When the valve device is in the open state (FIG. 2), for example, when the automobile runs in a slalom and the fuel in the fuel tank T fluctuates, the fuel flows into the valve chamber 2 from the inflow port 2a. Since the outflow is repeated, the open state of the valve device (FIG. 2) and the closed state of the valve device (FIGS. 3 and 4) are repeated, and the pressure in the valve chamber 2 increases to the pressure outside the valve chamber 2. It is conceivable that the valve device is in the open state (FIG. 2) or the intermediate state (FIG. 5) while the pressure in the fuel tank T is higher than that.
In this way, when the upper chamber and the valve chamber 2 communicate with each other while the pressure in the valve chamber 2 is high, the fuel that has entered or remains in the valve chamber 2 will flow into the upper portion together with the gas in the valve chamber 2 . There is a possibility that it will be ejected into the room.
However, according to the valve device of this embodiment, when the pressure in the valve chamber 2 is higher than the pressure in the fuel tank T outside the valve chamber 2 by a predetermined value or more, the check valve 11 is closed. By opening the valve, the pressure in the valve chamber 2 can be lowered, and the injection of fuel as described above can be effectively prevented.
Further, in the intermediate state of the valve device (FIG. 5), the upper chamber 1 and the valve chamber 2 communicate only within the range of the vent hole 6a of the main valve body 6, which is narrower than the valve opening 3a. 2, the pressure in the valve chamber 2 is higher than the pressure in the fuel tank T outside and outside the valve chamber 2. Therefore, the main valve body 6 has an annular flat plate which functions as the valve seat. It is conceivable that the main valve body 6 will not quickly separate from the valve opening 3a due to the force acting on the surface 12d. Since the pressure in the fuel tank T outside 2 can always be brought close to the pressure in the fuel tank T, the transition from the intermediate state to the valve open state is also made quickly.

Specifically, the pressure difference between the pressure in the valve chamber 2 and the pressure in the fuel tank T outside the valve chamber 2 causes the umbrella-shaped head 11a, which is in close contact with the outer surface of the upper case 9 due to its elastic restoring force, to move outward. The check valve 11 is in the open state when the force for forming a gap between the umbrella-shaped head 11a and the outer surface of the upper case 9 is applied to the umbrella-shaped head 11a. (see FIG. 8).

Main parts of the main body 7, the case 8, and the float body 4 can typically be easily and appropriately formed by synthetic resin moldings.

It goes without saying that the present invention is not limited to the embodiments described above, but includes all embodiments capable of achieving the objects of the present invention.

V valve device T fuel tank 1 upper chamber 1a vent 2 valve chamber 2a inlet 3 partition 3a valve opening 4 float body 11 check valve

Claims (3)

A valve mouth portion which is opened and closed by a float vertically movably housed in a partition wall separating an upper chamber having a ventilation portion to the outside of the fuel tank and a valve chamber formed below the upper chamber. A valve device formed by forming
A fuel inlet is formed in the valve chamber, and a check valve is provided above the inlet and below the partition wall to open when the pressure in the valve chamber becomes higher than the pressure in the fuel tank. valve device. The check valve includes an elastically deformable umbrella-shaped head that is brought into close contact with the outer surface of the valve chamber, and a fixing portion that is formed in the center of the umbrella-shaped head. 2. The valve device according to claim 1, wherein a ventilation portion formed in said valve chamber is closed at a portion between said portion and said umbrella-shaped head. The float body comprises a main body and a main valve body vertically movably interposed between the main body and the partition wall. 3. The valve device according to claim 1, comprising a valve body.

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