JPH06183271A - Bent cut valve of fuel tank - Google Patents

Abstract

PURPOSE:To shut off an evapo-tube during fuel supply by increasing an energizing force of a check valve of an elastic member with the opening operation of a value body during the fuel supply and increasing the pressure for opening the check valve to prevent the check valve from opening. CONSTITUTION:When the nozzle 24a of an oiling gun 24 in inserted into the gun inserting part 25 of a filler tube 23 during fuel supply, a shutter 53 makes its opening operation to press rod 42 of a bent cut valve 21. Then, the shaft 45 of a valve body 46 is pressed against a spring 48 and the valve body 46 opens a communicating hole 40a in a lower partition wall 40 to afford communication between first and second chambers 37, 38, i.e., between a bent tube 29 and 2 conduct tube 30. Further, the valve body 46 is lifted up by inserting the nozzle 24a and the energizing force of a spring 52 is substantially increased to increase the pressure for opening a check valve 50. Thus, a check valve is not opened if the internal pressure in a fuel tank is increased during fuel supply so that the full filling of fuel liquid surface is surely regulated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vent cut valve for a fuel tank for automobiles and the like.

[0002]

2. Description of the Related Art Some fuel tanks for automobiles are shown in FIG. In the figure, a filler tube 2 is attached to the tank body 1, and a vent cut valve 5 is attached to the filler tube 2 in the vicinity of the insertion portion of the nozzle 4 of the fueling gun 3.

Inside the tank main body 1, a vent tube 7 having a liquid level sensing valve 6 and a lower end of an evaporation tube 8 are provided so as to be adjacent thereto, and the evaporation tube 8 has a check valve 9,
It is connected to a canister 11 via a two-way valve 10. Further, the vent tube 7 is the vent cut valve 5
It is connected to the canister 11 via.

Here, the vent cut valve 5 connects and disconnects the first chamber 14 and the second chamber 15 of the valve casing 13 by the valve body 12, and the diaphragm 16
And a spring 17 closes the valve seat 18.
A shaft 19 of the valve body 12 projects into the filler tube 2, and a shutter 20 inside the filler tube 2 is provided.
Is opened by the nozzle 4 of the refueling gun 3, the shaft 19
Is pressed so that the valve body 12 opens the valve seat 18 to communicate the vent tube 7 (this structure is
It is shown in Japanese Utility Model Publication No. 2-109922).

Therefore, when the inside of the tank body 1 reaches a certain pressure, the check valve 9 opens to lower the pressure inside the tank body 1 to protect the tank body 1, and the evaporated fuel is led out from the evaporation tube 8 to the canister 11 and adsorbed. It Further, at the time of fuel refueling, the shutter 20 is opened by the nozzle 4 of the fuel refueling gun 3 and the vent cut valve 5 is opened, so that the first chamber 14 and the second chamber 15 communicate with each other and the vent tube 7 communicates with each other. As the liquid level rises, the evaporated fuel is led from the liquid level sensing valve 6 through the vent tube 7 to the canister 11 and adsorbed.

[0006]

At the time of refueling, when the amount of fuel supplied to the tank body 1 is large, the pressure in the tank body 1 rises. This pressure causes the check valve 9 to open. If the pressure is higher than the pressure, the check valve 9 will open, and therefore the evaporation tube 8
Is released. When the evaporation tube 8 is opened in this way, the fuel level rising during refueling is no longer regulated by the level sensing valve 6, and fuel is supplied beyond a predetermined level. There was a problem.

To solve this problem, a shut-out valve is provided in the evaporation tube 8 near the check valve 9,
When the nozzle 4 of the refueling gun 3 is inserted into the filler tube 2, it may be possible to detect this and close the shutout valve. However, the insertion state of the shutout valve and the nozzle 4 of the refueling gun 3 should be checked. Since a device for detection is required, there is a problem that the structure becomes complicated and expensive.

Therefore, the present invention provides a vent cut valve for a fuel tank having a function of shutting off the evaporation tube when fuel is refueled.

[0009]

A shutter that is opened by inserting a nozzle into a gun insertion portion of a filler tube into which a nozzle of a fuel refueling gun is inserted is provided. The shutter is interlocked with the shutter and is provided between a fuel tank and a canister. In a vent cut valve of a fuel tank having a valve body for opening and closing the passage of, the inside of the valve casing attached to the filler tube of the fuel tank communicates with the first chamber to which the vent tube is connected from near the filler tube and the canister. The second chamber and the third where the evaporation tube is connected
The lower partition wall partitioning the chamber and partitioning the first chamber and the second chamber and the upper partition wall partitioning the second chamber and the third chamber are respectively provided with communication holes, and the second chamber is The valve body is arranged so as to press the valve body through the shutter and open the communication hole of the lower partition wall, and the valve body is provided with a check valve for closing the communication hole of the upper partition wall. An elastic member provided between the valve body and the valve body biases the upper partition wall.

[0010]

[Function] When the pressure in the fuel tank rises above a certain level while the vehicle is traveling, the check valve operates to open the communication hole in the upper partition wall, so that the evaporated fuel passes from the fuel tank through the evaporation tube to the vent cut valve first. From the three chambers, through the communication holes to the second chamber, they are led out to the canister.

On the other hand, when the nozzle of the fueling gun is inserted into the filler tube during fuel refueling, the shaft inside the filler tube is pressed by the nozzle through the shutter, and the valve body opens the communication hole of the lower partition wall. As a result, the vent tube is opened, and fuel can be supplied until the fuel liquid level in the fuel tank reaches the open end of the vent tube.

At the time of refueling, since the valve body is opened, the urging force of the check valve by the elastic member increases and the valve opening pressure of the check valve increases, so the check valve is refueled. Prevent it from opening.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. First, the overall configuration of the fuel tank device including the vent cut valve 21 will be described with reference to FIG.

The fuel tank 22 for automobiles is provided with a filler tube 23 for supplying fuel. A gun insertion portion 25 for inserting the nozzle 24 a of the fueling gun 24 is provided on the upper portion of the filler tube 23.
A vent cut valve 21 is attached to a filler tube 23 adjacent to.

An evaporative tube 27 having an evaporative cut valve 26 at its tip and a vent tube 29 having a liquid level regulating valve 28 at its tip are inserted into the upper wall of the fuel tank 22, and the evaporative tube 27 and the vent tube 29 are inserted.
Is connected to each port of the vent cut valve 21 described later. Here, a lead-out tube 30 is connected to a port described later in the vent cut valve 21, and a canister 31 that adsorbs evaporated fuel is connected to the lead-out tube 30.

Next, the vent cut valve 21 will be described with reference to FIGS. A plate 32 is welded to the filler tube 23 to which the vent cut valve 21 is attached, and the vent cut valve 21 is fixed to this plate 32 via another plate 33 by bolts and nuts 34.

The valve casing 35 of the vent cut valve 21 is assembled to the plate 33 via a sealing material 36. Inside the valve casing 35, the first chamber 37, the second chamber 38, and the third chamber from the filler tube 23 side. Three
It is divided into 9 areas. Communication holes 40a and 41 are provided in a lower partition wall 40 that partitions the first chamber 37 and the second chamber 38 and an upper partition wall 41 that partitions the second chamber 38 and the third chamber 39, respectively.
a is formed.

A port 29a for connecting the vent tube 29 is provided in the first chamber 37, and a second chamber 38 is provided.
Is provided with a port 30a for connecting the lead-out tube 30, and the third chamber 39 is provided with a port 27a for connecting the evaporation tube 27.

The plates 32 and 33 are provided with a rod 42 as a shaft which penetrates the plates 32 and 33 and has a tip portion protruding into the filler tube 23. The rod 42 is slidably supported by the guide member 43, and the guide member 4
The head 42a of the rod 42 abuts on the seal member 44 interposed between the plate 3 and the plates 32 and 33 to prevent the rod 42 from coming off.

Inside the second chamber 38, a valve body 46 is provided which penetrates the lower partition wall 40 through the shaft 45 and opens and closes the communication hole 40a. Shaft 45 of valve body 46
A flange portion 47 is provided at the tip of the valve body 47, and the valve body 46 is pressed against the lower partition wall 40 and the flange portion 47 at the tip of the shaft 45 is provided between the flange portion 47 and the lower partition wall 40. A spring 48 is interposed as an elastic member to be pressed against the head 42a. Here, the rod 42 and the shaft 45 may be integrated.

The insertion portion 4 is provided at the center of the valve body 46.
9, a shaft 51 of a check valve 50 for opening and closing the communication hole 41a of the upper partition wall 41 is biased in the closing direction from the second chamber 38 side by a spring 52 as an elastic member. It is inserted in the state. An elastic seal material 56 made of rubber or the like is attached to a portion of the check valve 50 which is in close contact with the upper partition wall 41.

As shown in FIG. 2, the gun insertion portion 25 of the filler tube 23 is provided with a shutter 53 that can be opened and closed when the nozzle 24a of the oil supply gun 24 is inserted. The tip of the rod 42 is arranged so as to project within the range.

A nozzle seal 54 made of rubber is provided on the gun insertion portion 25. The nozzle seal 54 is formed by extending a pair of lip portions 54a in the insertion direction of the nozzle 24a of the fuel gun 24, and the surface of the lip portion 54a on the filler port 23 side of the filler tube 23 is made of resin or elastic metal. The guide member 54b is attached to the nozzle 2
The lip portion 54a is prevented from being damaged when the 4a is inserted.
In addition, 55 in FIG. 4 shows a relief valve.

Next, the operation will be described. First, when the vehicle is traveling or the like, as shown in FIG. 1, the valve body 46 of the vent cut valve 21 is connected to the communication hole 4 of the lower partition wall 40.
0a and the check valve 50 closes the communication hole 41a of the upper partition wall 41.
The vent tube 29 is shut off.

Here, the evaporated fuel in the fuel tank 22 increases and the pressure in the tank increases, and the vent cut valve 2
When the pressure in the first third chamber 39 exceeds the opening pressure of the check valve 50 provided by the elastic sealing material 56 and the spring 52 of the check valve 50, the check valve 50
Opens. As a result, the evaporated fuel in the fuel tank 22 is evaporated by the evaporation tube 27, the third chamber 39 of the vent cut valve 21,
The pressure in the fuel tank 22 is kept constant because it is sent from the outlet tube 30 to the canister 31 via the second chamber 38. Further, since the check valve 50 does not open unless the pressure inside the fuel tank 22 exceeds a certain level, it is possible to suppress the amount of fuel vapor generated.

Next, at the time of refueling the fuel, the refueling gun 24
The nozzle 24 a of the filler tube 23 to the gun insertion portion 2
5, the shutter 53 is opened to press the rod 42 of the vent cut valve 21. When the rod 42 is pressed, the shaft 45 of the valve body 46 causes the spring 4 to move.
When pressed against 8, the valve body 46 opens the communication hole 40a of the lower partition wall 40. As a result, the first chamber 37 and the second chamber 3
8, that is, the vent tube 29 and the outlet tube 30 communicate with each other.

Therefore, when fuel is supplied in this state, the highly concentrated vaporized fuel that is generated as the liquid level in the fuel tank 22 rises is led out from the vent tube 29 through the lead-out tube 30 and adsorbed to the canister 31, and is externally exposed. It will not be leaked. In addition, in the filler tube 23, the fuel seal gun 2 is provided by the nozzle seal 54 of the gun insertion portion 25.
Since the periphery of the No. 4 nozzle 24a is sealed, the evaporated fuel does not flow out from here either.

When the liquid level of the fuel reaches the liquid level control valve 28, the vent tube 29 closes and the evaporated fuel in the upper space of the fuel tank 22 loses its escape. Therefore, the liquid level in the filler tube 23 rises and the refueling gun 24 automatically stops and ends refueling.

Here, at the time of refueling the fuel, the refueling amount may become larger than the evaporated fuel leaving the vent tube 29, and the pressure in the fuel tank 22 may become high. When the pressure in the fuel tank 22 becomes high and exceeds the opening pressure of the check valve 50 when the vehicle is traveling, the check valve 50 is conventionally opened, whereby the evaporated fuel in the upper space of the fuel tank 22 is discharged from the evaporation tube 27. Since the liquid comes out, the liquid level regulation by the liquid level regulating valve 28 does not work, and the fuel liquid level rises above a predetermined position. However, by inserting the nozzle 24a of the refueling gun 24, the valve body 46 is pushed up, and the urging force of the spring 52 is greatly increased, and the opening pressure of the check valve 50 is increased. I can't reach it. Therefore, the fuel level is kept at a predetermined position.

When the fuel is supplied, the refueling gun 24
When the nozzle 24a of the above is vigorously inserted into the gun insertion portion 25, the shutter 53 is opened first, and then the valve body 46 is suddenly opened by the retracting operation of the rod 42. This sudden operation is absorbed by the buffering action of the spring 52. In addition, the check valve 50 smoothly closes the communication hole 41a of the upper partition wall 41 because the elastic sealing material 56 also has a further cushioning effect. Therefore, the impact applied to the check valve 50 can be mitigated.

In this way, the vent cut valve 21
The check valve 50 is attached to the valve and the opening pressure of the check valve 50 at the time of fuel supply is changed by effectively utilizing the movement of the valve body 46 which is opened by the nozzle 24a of the fuel gun 24 during fuel supply.
Therefore, a shutout valve for detecting the insertion state of the nozzle of the refueling gun and closing the evaporation tube as in the conventional art is not required, and a device for detecting the insertion state of the nozzle of the refueling gun is not required, and the manufacturing cost can be reduced. .

[0032]

As described above, according to the present invention, when the pressure in the fuel tank rises above a certain level while the vehicle is traveling, the check valve operates to connect the second chamber and the third chamber. The evaporated fuel in the fuel tank is released, and the pressure in the fuel tank can be kept below a certain pressure.

On the other hand, when the nozzle of the fueling gun is inserted into the filler tube and the shutter is opened at the time of fueling,
As a result, the valve body is opened to ensure the venting action at the time of refueling the fuel, but at the same time, the opening operation of the valve body increases the biasing force of the elastic member, which increases the valve opening pressure of the check valve. Therefore, even when the internal pressure of the fuel tank becomes high at the time of refueling the fuel, the check valve does not open, and the fuel liquid level can be surely restricted.

Further, a sensor for detecting the insertion state of the nozzle of the refueling gun is not required, and the check valve is integrally incorporated, so that the manufacturing cost can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 is a side view showing the same attachment state.

FIG. 3 is a front view of FIG.

FIG. 4 is an overall explanatory view of a fuel tank.

FIG. 5 is an overall explanatory view of a conventional technique.

[Explanation of symbols]

 22 ... Fuel tank 23 ... Filler tube 24 ... Refueling gun 24a ... Nozzle 27 ... Evaporation tube 29 ... Vent tube 35 ... Valve casing 37 ... First chamber 38 ... Second chamber 39 ... Third chamber 40 ... Lower partition walls 40a, 41a ... Communication hole 41 ... Upper partition wall 42 ... Rod (shaft) 45 ... Shaft 46 ... Valve main body 48 ... Spring (elastic member) 50 ... Check valve 52 ... Spring (elastic member) 53 ... Shutter

Claims (1)

[Claims] 1. A shutter which is opened by inserting a nozzle into a gun insertion portion of a filler tube into which a nozzle of a fuel refueling gun is inserted is provided, and a passage between the fuel tank and the canister is opened and closed by interlocking with the shutter. In a fuel tank vent cut valve having a valve body that
Inside the valve casing attached to the filler tube of the fuel tank, the first chamber to which the vent tube is connected from the filler tube side and the second chamber that communicates with the canister
To form a chamber and a third chamber to which the evaporation tube is connected, and to form a lower partition wall that partitions the first chamber and the second chamber, and an upper partition wall that partitions the second chamber and the third chamber. A communication hole is provided in each of the second chambers, the valve body is arranged in the second chamber so as to press the valve body through the shutter to open the communication hole of the lower partition wall, and the communication hole of the upper partition wall is provided in the valve body. A vent cut valve for a fuel tank, wherein a check valve for closing is provided, and the check valve is urged to an upper partition wall by an elastic member provided between the check valve and the valve body.