JP2011011645A - Fuel shut-off valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel shut-off valve for materializing an introduction passage 50P capable of easily discharging a fuel in a valve chamber 20S by a simple structure.SOLUTION: The fuel shut-off valve 10 includes a casing 20 in which the valve chamber 20S is formed by a casing body 30 and a bottom member 35 and a communicating hole 31a, a float mechanism 60 stored in the valve chamber 20S and a passage forming member 50. In the passage forming member 50, an introducing opening 57c of which one side is connected with the communication hole 31a and another side opens in a fuel tank FT is formed. The introducing opening 57c is formed at a position lower than the communication hole 31a and lower than a closing valve liquid level h1. An introduction passage 50P includes a sealing opening 52a closed by the fuel of which liquid level is lower than a full liquid level FL1.

Description

  The present invention relates to a fuel shut-off valve that is disposed at an upper portion of a fuel tank of a vehicle and that allows fuel vapor in the fuel tank to escape during fueling and regulates fuel outflow when the fuel reaches a predetermined liquid level.

  Conventionally, as described in Patent Document 1, this type of fuel shut-off valve allows fuel vapor to escape to the canister during refueling and closes the connection passage when fuel is supplied to a predetermined full tank level. This prevents the fuel from flowing out. Such a fuel shut-off valve includes a casing that forms a valve chamber and a float that is housed in the valve chamber. An introduction opening is formed in the lower part of the casing to connect the fuel tank and the valve chamber to introduce fuel into the valve chamber. When the introduction opening is closed with fuel during refueling, the valve chamber and the tank Fuel is introduced into the valve chamber from the introduction opening with a pressure difference from the internal pressure, the float is raised, and the connection passage is closed.

  However, in the conventional fuel cutoff valve, the distance between the introduction opening at the lower part of the casing and the upper wall of the fuel tank is increased, and a dead space without fuel is formed in the fuel tank. In order to solve these problems, as described in Patent Document 2, the introduction opening is disposed at a position higher than the valve closing liquid level at which the main float that opens and closes the connection passage is closed, and the introduction opening is sub- A configuration that opens and closes by a float is also known. Such a sub-float valve needs to be provided with a discharge valve for discharging fuel from the valve chamber, and has a complicated structure. In addition, in other conventional techniques, the fuel level is lowered by the height of the subfloat, the dead space cannot be sufficiently reduced, and the position of the introduction opening is also regulated by the arrangement of the subfloat. For this reason, there is a problem that it is difficult to install the introduction opening at an optimum position according to the shape of the fuel tank.

JP 2004-84496 A JP 2006-97674 A

  The present invention, based on solving the problems of the prior art, can easily realize a configuration that can easily discharge the fuel in the valve chamber, can reduce the dead space in the fuel tank, Moreover, it is an object of the present invention to provide a fuel cutoff valve in which an introduction opening for detecting a full tank position can be installed with a simple configuration at a position apart from the float mechanism.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

[Application Example 1]
Application Example 1 is a fuel shut-off valve that is attached to the upper part of the fuel tank and opens and closes a connection passage that connects the inside and outside of the fuel tank to cut off the communication between the fuel tank and the external passage.
A casing having a casing body which forms a valve chamber connecting the connection passage and the fuel tank, and has a communication hole;
A passage forming member connected to the communication hole of the casing body and having an introduction opening for introducing the fuel vapor of the fuel tank, and forming an introduction passage for introducing the fuel vapor from the introduction opening to the valve chamber through the communication hole; ,
A float mechanism that is housed in the valve chamber and rises when the fuel in the valve chamber reaches a valve closing liquid level and closes the connection passage;
With
The introduction opening is formed at a position lower than the communication hole,
The introduction passage has an upper passage formed by bending to a position higher than the introduction opening and the communication hole,
Further, the passage forming member has a side passage forming member disposed so as to surround an outer side of the side wall portion of the casing, and between the side passage forming member and the side wall portion of the casing body. A tank having a sealing opening disposed below the introduction opening, the sealing opening being closed with fuel at the time of refueling, and when the introduction opening is closed with fuel due to a rise in fuel level; The fuel cell is configured in an airtight state so that fuel is introduced into the valve chamber through the sealing opening due to a pressure difference between an internal pressure and the valve chamber.

  When the fuel is supplied to the fuel tank using the fuel shut-off valve described in Application Example 1 and reaches the fuel level that closes the sealing opening, the introduction passage becomes airtight. When the fuel liquid level that closes the introduction opening is reached, the tank internal pressure in the fuel tank is increased, and the fuel flows into the valve chamber through the sealing opening due to the pressure difference between the tank internal pressure and the valve chamber. When the fuel in the valve chamber reaches a predetermined valve closing liquid level, the float mechanism is raised to close the connection passage. At this time, an automatic stop for stopping the fuel supply of the fuel gun can be activated by detecting the increase in the tank internal pressure by the sensor or detecting that the fuel in the filler pipe has reached the fuel gun.

  At the liquid level at which the fuel closes the sealing opening lower than the full tank level, the introduction passage becomes airtight, and the fuel can be introduced into the valve chamber by the siphon action. Such a sealing opening quickly discharges fuel in the valve chamber when the valve is opened. Moreover, the sealing opening does not need to have a small passage area in order to obtain an airtight state in the introduction passage, and it is not necessary to provide a discharge valve as described in the prior art. Can be.

  Moreover, the passage forming member can arrange the introduction opening for detecting the full tank liquid level at a position away from the casing forming the valve chamber according to the shape of the fuel tank. That is, when the introduction opening of the passage forming member is arranged at the center of the fuel tank, the influence of the vehicle inclination can be reduced, that is, even if the vehicle is inclined, the fuel level is at the full liquid level. No fuel enters the valve chamber of the fuel shut-off valve and the float mechanism does not rise until reaching the position, so that the full tank liquid level can be set to a constant liquid level regardless of the inclination of the vehicle. Moreover, if the introduction opening is installed in the center of the fuel tank, the full tank level can be higher than the position of the communication hole at the lower end of the casing body of the fuel shut-off valve, reducing the dead space of the fuel tank and increasing its capacity Can be made.

  Further, since the passage forming member has an upper passage disposed at a position higher than the introduction opening, even if fuel closes the introduction opening due to a temporary inclination of the vehicle, the tank internal pressure is not so large except during refueling. Therefore, the siphon action is not induced and fuel is not guided to the valve chamber, so that the fuel shut-off valve does not cause an inadvertent closing operation.

It is sectional drawing which shows the fuel tank of the motor vehicle carrying the fuel cutoff valve concerning one Example of this invention. FIG. 2 is an enlarged cross-sectional view of the vicinity of a fuel cutoff valve in FIG. It is sectional drawing which shows the valve closing state of a fuel cutoff valve. It is sectional drawing which decomposed | disassembled the fuel cutoff valve. It is sectional drawing to which the 3rd channel | path formation part was expanded. It is explanatory drawing explaining the effect | action of a fuel cutoff valve. It is sectional drawing which shows the fuel tank of the motor vehicle carrying the fuel cutoff valve concerning the other Example of this invention.

  In order to further clarify the configuration and operation of the present invention described above, preferred embodiments of the present invention will be described below.

(1) Schematic configuration of fuel cutoff valve 10 FIG. 1 is a cross-sectional view showing a fuel tank FT of an automobile equipped with a fuel cutoff valve 10 according to one embodiment of the present invention. In FIG. 1, the fuel tank FT is a flat resin fuel tank, the surface thereof is formed of a composite resin material containing polyethylene, and the mounting hole FTb is formed in the tank upper wall FTa. The fuel shut-off valve 10 is attached to the tank upper wall FTa with its lower part protruding into the attachment hole FTb, and the passage forming member 50 penetrates and enters substantially the center of the fuel tank FT. The fuel shut-off valve 10 introduces fuel through a sealing opening when fuel in the fuel tank FT rises to a predetermined full tank liquid level FL1 during refueling, and regulates the outflow to the canister and functions as an auto stop. Is.

(2) Configuration of Each Part of Fuel Shutoff Valve 10 FIG. 2 is an enlarged sectional view of the vicinity of the fuel cutoff valve 10 of FIG. 1, and FIG. 3 is a sectional view showing a closed state of the fuel cutoff valve 10. That is, when the fuel cutoff valve 10 reaches the full tank level FL1 when the fuel is supplied to the fuel tank FT by refueling as shown in FIG. 3 from the opened state of FIG. The fuel is introduced through the formed sealing opening to make the auto stop function. 2 and 3, the fuel cutoff valve 10 includes a casing 20, a passage forming member 50, a float mechanism 60, and a spring 68 as main components. These casings 20 and the like are made of polyethylene, polyamide, or polyacetal. It is formed from resin.

  FIG. 4 is an exploded sectional view of the fuel cutoff valve 10. The casing 20 includes a casing main body 30, a bottom member 35, and a lid body 40. A space surrounded by the casing main body 30 and the bottom member 35 is a valve chamber 20S, and a float mechanism is provided in the valve chamber 20S. 60 is stored. The float mechanism 60 is supported by a spring 68.

  The casing body 30 includes a cylindrical side wall portion 31 and an upper wall portion 32 formed integrally with the upper portion of the side wall portion 31. A communication hole 31 a is formed in the lower portion of the side wall portion 31. The lower portion of the casing body 30 is an opening 30a that opens the valve chamber 20S downward. A central portion of the upper wall portion 32 is a connection passage 32a, and a seal portion 32b is formed along the periphery of the opening. A flange 33 is formed on the side of the side wall 31. The lower surface of the flange 33 is positioned by the positioning portion 33a and attached to the tank upper wall FTa (FIG. 2) of the fuel tank FT. On the upper surface, an annular weld portion 33b for welding the lid 40 is provided. Is formed.

  The bottom member 35 is a member that is disposed so as to close the opening 30a at the lower end of the side wall 31 and supports the float mechanism 60 via a spring 68, and includes a disc-shaped bottom main body 35a. A discharge hole 35b is formed in the bottom main body 35a. The bottom member 35 includes a cylindrical body 35c protruding in a cylindrical shape from the outer peripheral portion of the bottom main body 35a, and includes an engaging claw 35d on the outer peripheral portion of the cylindrical body 35c.

  The lid body 40 includes a lid body 41 that covers the upper portion of the casing body 30 and a tube body 42 that protrudes from the side of the lid body 41. In FIG. 4, the tubular body 42 represents a state of protruding beyond the paper surface. A passage 42 a is formed in the tube body 42. One end of the passage 42a is connected to the valve chamber 20S via the connection passage 32a, and the other end is connected to the canister side.

  As shown in FIG. 2, the passage forming member 50 is a member that forms an introduction passage 50 </ b> P that passes through the outside of the fuel tank FT from the communication hole 31 a of the side wall portion 31 of the casing body 30 and enters the fuel tank FT. The introduction passage 50P is a passage for introducing fuel vapor into the valve chamber 20S in accordance with the fuel level in the fuel tank FT. The passage forming member 50 includes a first passage forming portion 51, a second passage forming portion 55, and a third passage forming portion 56, and thereby, a first passage 51P and a second passage 55P constituting the introduction passage 50P. And the 3rd channel | path 56P is formed.

  The first passage forming portion 51 is provided in a cylindrical shape from below the flange 33, is formed on the side passage forming member 52 disposed on the outer peripheral side of the casing body 30, the side portion of the lid body 40, and the lid. And a lead-out passage forming member 53 protruding to the side of the body 40. The side passage forming member 52 has an engagement hole 51a, and the engagement claw 35d of the bottom member 35 is engaged with the engagement hole 51a to hold the bottom member 35. Further, the side passage forming member 52 surrounds the side wall 31 of the casing body 30 and the cylindrical body 35c of the bottom member 35, and the space therebetween is an annular passage 51Pa that constitutes a part of the first passage 51P. The annular passage 51Pa is connected to the communication hole 31a. The annular passage 51Pa is connected to the fuel tank FT through a sealing opening 52a formed in the lower part of the side passage forming member 52 and the bottom member 35.

  The lead-out passage forming member 53 protrudes in a tubular shape from the side portion of the lid body 40, and forms a pipe passage 51Pb that constitutes a part of the first passage 51P. One end of the pipe passage 51Pb is connected to the annular passage 51Pa. One end of the lead-out passage forming member 53 is an external connection portion 53b.

  The second passage forming portion 55 is formed of a resin tube and constitutes a second passage 55P (upper passage). One end of the second passage forming portion 55 is connected to the external connection portion 53b, and the other end is the third passage forming portion 56. It is connected to the.

  FIG. 5 is an enlarged cross-sectional view of the third passage forming portion 56. The third passage forming portion 56 is a joint member that is connected to the end portion of the second passage forming portion 55 and forms a passage that enters in a state where the inside and outside of the fuel tank FT are sealed, and a tube that forms the third passage 56P. A main body 57 and a welded portion 58 that protrudes in a disk shape from the outer peripheral portion of the tube main body 57 and is welded to the fuel tank FT are provided. The pipe body 57 includes a connection part 57a for connecting the end of the second passage forming part 55, and an introduction pipe 57b protruding into the fuel tank FT. The lower end of the introduction pipe 57b is an introduction opening 57c that defines a full tank liquid level FL1. The introduction opening 57c is disposed at a position lower than the communication hole 31a in FIG.

  In FIG. 4, the float mechanism 60 includes a cylindrical float 61 and a rubber valve element 65 disposed on the top of the float 61. The float 61 has a buoyancy chamber 61S opened downward. A valve mounting portion 61 a is projected from the center upper portion of the float 61. A valve body 65 is attached to the valve attachment portion 61a. The valve body 65 is attached to and detached from the seal portion 32b.

(3) Operation of the fuel cutoff valve 10 Next, the operation of the fuel cutoff valve 10 will be described. As shown in FIG. 2, when fuel is supplied into the fuel tank FT by refueling, the fuel vapor accumulated in the upper part of the fuel tank FT as the fuel liquid level in the fuel tank FT rises is discharged into the discharge holes 35b and The inlet passage 50P enters the valve chamber 20S through a passage such as the communication hole 31a from the annular passage 51Pa, and escapes from the valve chamber 20S to the canister side through the connection passage 32a and the passage 42a. When the fuel level reaches the sealing opening 52a and the fuel closes the sealing opening 52a, the introduction passage 50P is almost airtight from the introduction opening 57c to the communication hole 31a. Then, as shown in FIG. 3, the fuel level in the fuel tank FT reaches a predetermined full tank level FL1, and the introduction opening 57c of the third passage 56P of the third passage forming portion 56 is closed, thereby fuel. The tank internal pressure in the tank FT increases. In this state, the differential pressure between the tank internal pressure and the pressure in the valve chamber 20S increases, and fuel flows into the valve chamber 20S through the sealing opening 52a by siphon action. When the fuel liquid level in the valve chamber 20S reaches the valve closing liquid level h1, the upward force due to the buoyancy of the float 61 and the load of the spring 68, and the downward force due to the weight of the float 61 and the valve body 65, When the former exceeds the latter, the float 61 and the valve body 65 rise together, and the valve body 65 sits on the seal portion 32b and closes the connection passage 32a. As a result, the tank internal pressure further increases, the fuel level in the inlet pipe rises, and when the fuel comes into contact with the nozzle of the fuel gun, the fuel supply is stopped by the sensor. As a result, when fuel is supplied to the fuel tank FT, fuel vapor can escape from the fuel tank FT and fuel can be prevented from flowing out of the fuel tank FT. On the other hand, when the fuel level in the fuel tank FT decreases and the fuel in the valve chamber 20S is discharged through the discharge hole 35b, the communication hole 31a, the annular passage 51Pa, and the sealing opening 52a, the float 61 has its buoyancy. Therefore, the valve body 65 is separated from the seal portion 32b and opens the connection passage 32a.

(4) Operation / Effect of Fuel Shutoff Valve 10 The fuel cutoff valve 10 according to the above embodiment provides the following operational effects.
(4) -1 As shown in FIG. 3, when the fuel is supplied to the fuel tank FT, the passage forming member 50 closes the sealing opening 52a and further closes the introduction opening 57c. When the internal pressure is increased and the fuel flows into the valve chamber 20S through the introduction passage 50P due to the pressure difference between the tank internal pressure and the valve chamber 20S, the float mechanism 60 closes the connection passage 32a, and the tank internal pressure further increases. The fuel level in the filler pipe is raised, and an automatic stop that stops refueling of the fuel gun can be activated.

(4) -2 In FIG. 1, the passage forming member 50 has an introduction opening 57c for detecting the full tank liquid level FL1 at a position separated from the casing 20 that forms the valve chamber 20S according to the shape of the fuel tank FT. It can arrange | position suitably. In the present embodiment, as shown in FIG. 6, when the introduction opening 57c of the passage forming member 50 is arranged at the center of the fuel tank FT, the influence of the inclination of the vehicle can be reduced, that is, the fuel tank Even if there is an FT inclination (about 3 °), if the full liquid level FL1 is set at a position lower than the liquid level h2 at which the upper end of the communication hole 31a is submerged, the communication hole 31a is passed through the passage forming member 50. Since the fuel does not flow into the valve chamber 20S and the float mechanism 60 does not rise, the full liquid level FL1 can be set to a constant liquid level. Moreover, when the introduction opening 57c is installed at the center of the fuel tank FT, the full tank liquid level FL1 can be made higher than the lower end of the casing body 30 of the fuel cutoff valve 10, reducing the dead space of the fuel tank FT and increasing its capacity. Can be increased.

(4) -3 As shown in FIG. 2, since the second passage 55P of the passage forming member 50 is routed outside the fuel tank FT, it does not interfere with the member disposed inside the fuel tank FT. The space in the fuel tank FT can be used effectively.

(4) -4 Since the second passage forming portion 55 of the passage forming member 50 is an upper passage disposed at a position higher than the introduction opening 57c, the fuel blocks the introduction opening 57c with a temporary inclination of the vehicle. However, the tank internal pressure does not increase so much except during refueling, the siphon action is not induced, and the fuel is not guided to the valve chamber 20S, so that the fuel cutoff valve 10 does not cause an unexpected valve closing operation.

  FIG. 7 is a cross-sectional view showing a fuel tank FT of an automobile equipped with a fuel cutoff valve 10B according to another embodiment of the present invention. This embodiment is characterized by the structure of a so-called in-tank type fuel cutoff valve 10B in which the fuel cutoff valve 10B is mounted in the fuel tank FT. That is, the fuel cutoff valve 10B is attached to the fuel tank FT via an attachment portion 20Ba formed integrally with the casing 20B on the upper portion thereof. The passage forming member 50B is disposed in the fuel tank FT and on the side of the casing main body 30B, and the introduction opening 57Bc is disposed at the full liquid level FL1 higher than the sealing opening 52Ba. Thus, the passage forming member 50B may be arranged inside the fuel tank FT in addition to the configuration passing through the outside of the fuel tank FT.

The present invention is not limited to the above-described embodiments, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.
In the above embodiment, the discharge hole is provided in the bottom member to facilitate the discharge of the fuel in the valve chamber. By providing, the discharge hole can be eliminated.

DESCRIPTION OF SYMBOLS 10 ... Fuel cutoff valve 10B ... Fuel cutoff valve 20 ... Casing 20B ... Casing 20S ... Valve chamber 20Ba ... Mounting part 30 ... Casing main body 30B ... Casing main body 30a ... Opening 31 ... Side wall part 31a ... Communication hole 32 ... Upper wall part 32a ... Connection passage 32b ... Sealing part 33 ... Flange 33a ... Positioning part 33b ... Annular weld 35 ... Bottom member 35a ... Bottom body 35b ... Discharge hole 35c ... Cylindrical body 35d ... Engagement claw 40 ... Lid body 41 ... Lid body 42 ... Tube Body 42a ... passage 50 ... passage forming member 50B ... passage forming member 50P ... introduction passage 51 ... first passage forming portion 51P ... first passage 51a ... engagement hole 51Pa ... annular passage 51Pb ... pipe passage 52 ... side passage forming member 52a ... Sealing opening 52Ba ... Sealing opening 53 ... Derivation passage forming member 53b ... External connection portion 55 ... Second passage forming portion 55 P ... Second passage 56 ... Third passage formation portion 56P ... Third passage 57 ... Pipe body 57a ... Connection portion 57b ... Introduction tube 57c ... Introduction opening 57Bc ... Introduction opening 58 ... Welding portion 60 ... Float mechanism 61 ... Float 61S ... Buoyancy chamber 61a ... Valve mounting portion 65 ... Valve element 68 ... Spring FT ... Fuel tank FTa ... Tank upper wall FTb ... Mounting hole

Claims (1)

A fuel shut-off valve that is mounted on the upper portion of the fuel tank (FT) and that opens and closes a connection passage (32a) that connects the inside of the fuel tank (FT) and the outside to open and close the communication between the fuel tank (FT) and the outside passage. ,
A casing (20) having a casing body (30) which forms a valve chamber (20S) connecting the connection passage (32a) and the inside of the fuel tank (FT) and has a communication hole (31a);
There is an introduction opening (57c) that is connected to the communication hole (31a) of the casing body (30) and introduces fuel vapor of the fuel tank (FT), and the fuel vapor is introduced into the communication hole from the introduction opening (57c). A passage forming member (50) forming an introduction passage (50P) leading to the valve chamber (20S) through (31a);
A float mechanism (60) which is housed in the valve chamber (20S) and rises when the fuel in the valve chamber (20S) reaches the valve closing liquid level (h1) to close the connection passage (32a);
With
The introduction opening (57c) is formed at a position lower than the communication hole (31a),
The introduction passage (50P) has an upper passage formed by bending to a position higher than the introduction opening (57c) and the communication hole (31a),
Further, the passage forming member (50) has a side passage forming member (52) arranged so as to surround the outside of the side wall portion (31) of the casing (20), and the side passage forming member ( 52) and a side wall portion (31) of the casing body (30) and a sealing opening (52a) disposed below the introduction opening (57c), the sealing opening (52a) Is closed with fuel at the time of refueling, and when the introduction opening (57c) is closed with fuel due to a rise in the fuel liquid level, the pressure difference between the tank internal pressure and the valve chamber (20S) causes A fuel shut-off valve, characterized in that the fuel shut-off valve is configured to be airtight so as to introduce fuel into the valve chamber (20S) through the stop opening (52a).

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