JP5315146B2 - Fuel shut-off valve - Google Patents

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 flow out during refueling and regulates fuel outflow when the fuel reaches a predetermined liquid level.

  Conventionally, this type of fuel shut-off valve allows fuel vapor to escape to the canister during refueling, and prevents the fuel from flowing out by closing the connection passage when the fuel is supplied to a predetermined full tank level. doing. As described in Patent Document 1, such a fuel cutoff 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 in which the valve closing liquid level is raised by opening and closing with a float is also known. However, in other conventional technologies, the fuel level is lowered by the height of the sub-float, the dead space cannot be made sufficiently small, and the position of the introduction opening is also regulated by the arrangement of the sub-float. 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

  In view of solving the above-described problems of the conventional technology, the present invention can reduce the dead space in the fuel tank, and can easily provide an introduction opening for detecting a full tank position at a position away from the float mechanism. It aims at providing the fuel cutoff valve which can be installed with a structure.

  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 mounted in a state where a part of the fuel tank is inserted into the upper mounting hole of the fuel tank, and connects the fuel tank and the external passage by opening and closing a connection passage that connects the inside and outside of the fuel tank. In the fuel shutoff valve to shut off,
A casing having a cylindrical casing body and a bottom member disposed at a lower portion of the casing body, wherein the casing body and the bottom member form a valve chamber, and a communication hole is formed in the bottom member; ,
A float mechanism supported by the bottom member and housed in the valve chamber, which rises when the fuel liquid level in the valve chamber reaches the valve closing liquid level and closes the connection passage;
A passage forming member having an introduction passage for guiding the fuel in the fuel tank to the valve chamber, wherein one of the introduction passages is connected to the communication hole, and the other is formed with an introduction opening opened in the fuel tank;
With
The casing main body and the passage forming member allow fuel to be introduced into the introduction passage by a differential pressure between a tank internal pressure of the fuel tank and a pressure in the valve chamber when the fuel liquid level reaches a fuel liquid level closing the introduction opening. , Is led to the valve chamber through the communication hole, and is configured in an airtight state in which the float mechanism is raised to close the connection passage,
The passage forming member is bent out so as to be led out of the fuel tank and to enter the fuel tank so as to form an introduction opening. Further, the passage forming member is at the lowest position of the passage forming member and the fuel tank. A discharge hole is formed in a portion inside.

  When fuel is supplied to the fuel tank using the fuel shut-off valve described in Application Example 1 and reaches a fuel level that closes the introduction opening, the tank internal pressure in the fuel tank increases, and the pressure in the tank and the pressure in the valve chamber increases. Due to the difference, the fuel flows into the valve chamber through the introduction passage of the passage forming member. 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. When the fuel level in the fuel tank is lowered, the fuel in the valve chamber and the passage forming member is discharged into the fuel tank from the discharge hole in the fuel tank at the lowest position of the passage forming member.

  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.

  Furthermore, since the passage forming member is arranged outside the fuel tank, the space in the fuel tank can be effectively used without interfering with the member arranged inside the fuel tank.

[Other application examples]
A casing according to another application example can be attached from the outside of the fuel tank and has a lid body assembled to the casing body, and the passage forming member extends from the communication hole to a side wall portion of the casing body. and along and first passage forming component having a connecting unit disposed outside the fuel tank through the lid, the second passage forming component for forming a top position passage is connected to the first passage forming component And a third passage forming portion that is connected to the second passage forming portion and enters the fuel tank while sealing the inside and outside of the fuel tank and has the introduction opening. Further, passing path forming member can be the structure that is led out to the outside of the fuel tank in a state of being sealed by fitting member fixed to the tank upper wall of the fuel tank.

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. 1. 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 sectional drawing which decomposed | disassembled the float mechanism. It is explanatory drawing explaining operation | movement 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 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. Further, through the passage forming member 50, the fuel tank FT penetrates and enters almost the center of the fuel tank FT. . The fuel shut-off valve 10 introduces fuel through the passage forming member 50 when the fuel in the fuel tank FT rises to a predetermined full tank liquid level FL1 at the time of refueling, and regulates the outflow to the canister and functions as an automatic stop. It is something to be made.

(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. 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 integrally formed on the upper portion of the side wall portion 31. A flange 31 a for welding to the lid body 40 is formed on the upper portion of the side wall portion 31. A connection passage 32a is formed through the central portion of the upper wall portion 32, and a seal portion 32b is formed along the periphery of the opening. Moreover, the opening peripheral part of the upper part of the connection channel | path 32a is the barrier 32c for returning a fuel.

  The bottom member 35 is a member that is welded to the lower end of the side wall portion 31 and supports the float mechanism 60 via a spring 68, and includes a disk-shaped bottom main body 35a. A welded portion 35b that is welded to the lower end of the casing main body 30 is formed on the outer peripheral portion of the bottom main body 35a, and a communication hole 35c is formed on the inner side thereof.

  The lid body 40 includes a lid main body 41, a tube body portion 42 projecting laterally from the center of the lid main body 41, and a flange 43 formed on the outer periphery of the lid main body 41, and these are integrally formed. . A tube passage 42a is formed in the tube body portion 42. One end of the tube passage 42a is connected to the valve chamber 20S through the connection passage 32a, and the other end is connected to the canister (not shown). An inner welded portion 41a welded to the flange 31a of the casing main body 30 is formed on the inner peripheral side of the lower portion of the lid main body 41, and a tank upper wall FTa (see FIG. The welding part 43a welded to 2) is formed.

  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 lower portion of the casing body 30 and enters the fuel tank FT. The introduction passage 50P is a passage for introducing fuel 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.

  In FIG. 4, the first passage forming portion 51 includes a lower passage forming member 52 disposed at the lower portion of the casing body 30, and a lead-out passage projecting from the lower portion of the lid body 40 and disposed on the side of the casing body 30. And a forming member 53. The lower passage forming member 52 is integrally formed with a disc-shaped bottom member 52a, an outer peripheral wall 52b protruding from the outer peripheral portion of the bottom member 52a, and a connecting portion 52c formed at the end of the bottom member 52a. And is welded to the lower end of the casing body 30 by a welded portion 52d at the upper part of the outer peripheral wall 52b. A space surrounded by the lower passage forming member 52 and the bottom member 35 is a lower chamber 51Pa constituting a part of the first passage 51P. The bottom member 52a has a discharge hole 52e that communicates the lower chamber 51Pa with the fuel tank FT at the lowest position of the passage forming member 50 with a diameter of about φ0.5 mm. The lead-out passage forming member 53 extends downward through the lid main body 41 of the lid body 40, and is fixed to the connecting portion 52c at the lower end thereof and connected to the lower chamber 51Pa. A vertical passage 51Pb constituting the part is formed. An upper portion of the lead-out passage forming member 53 is an external connection portion 53b formed by bending the lid body 40 in the horizontal direction. 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 projecting in a cylindrical shape from the outer peripheral portion of the tube main body 57 and 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 higher than the communication hole 35c in FIG.

  FIG. 6 is an exploded cross-sectional view of the float mechanism 60. The float mechanism 60 includes a float 61 and an upper float 65 disposed on the top of the float 61. The float 61 includes a float main body 62 having a buoyancy chamber 61S opened downward, and a flange 63 for preventing an upper float 65 projecting from the upper portion of the float main body 62 from coming off. A valve portion 61 a protrudes from the center upper portion of the float 61. A guide protrusion 62 a is formed on the lower outer periphery of the float body 62. The guide protrusions 62a are provided on the side wall of the float main body 62 so as to protrude in eight ribs at equal intervals in the circumferential direction and in a rib shape in the vertical direction. The float 61 is supported by a spring 68 (FIG. 2) spanned between the bottom member 35 and the upper surface of the buoyancy chamber 61S.

  The upper float 65 is a valve for improving the restart valve characteristic, and is supported on the upper part of the float 61 so as to be movable up and down. A communication hole 65b that is opened and closed by the valve portion 61a is formed in the center of the disc 65a. ing. The lower end of the communication hole 65b is a seal portion 65c. In addition, an engaging claw 65d that engages with the outer peripheral portion of the flange portion 63 projects from the lower end of the outer periphery of the disc 65a. A rubber valve element 67 is mounted on the upper float 65, and the valve element 67 is attached to and detached from the seal portion 32b (FIG. 4).

(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 passes through the introduction passage 50P. That is, the third passage 56P of the third passage formation portion 56, the second passage 55P of the second passage formation portion 55, the first passage 51P of the first passage formation portion 51, and the communication hole 35c enter the valve chamber 20S. The valve chamber 20S escapes to the canister side through the connection passage 32a and the pipe passage 42a. 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 introduction passage 50P by siphon action. In addition, since the discharge hole 52e has a small passage area, the above-described differential pressure is not affected. As shown in FIG. 3, when the fuel level in the valve chamber 20S reaches the valve closing level h1, the buoyancy of the float 61 and the upward force due to the load of the spring 68, the float 61 and the upper float 65 When the former exceeds the latter due to the balance with the downward force due to its own weight, the float 61 and the upper float 65 rise together, and the valve body 67 is seated on the seal portion 32b and passes through the connection passage 32a. close up. 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. Thereby, at the time of refueling to the fuel tank FT, it is possible to escape the fuel vapor from the fuel tank FT and to prevent the fuel from flowing out of the fuel tank FT.

  On the other hand, when the fuel level in the fuel tank FT is lowered and the fuel in the valve chamber 20S is discharged through the discharge hole 52e, the float 61 is lowered with its buoyancy reduced, so that the valve portion 61a is sealed. The communication hole 65b is opened away from the seat 65c. Due to the communication of the communication hole 65b, the pressure below the upper float 65 becomes substantially the same pressure as that in the vicinity of the connection passage 32a, so that the force for closing the upper float 65 is reduced, and the flange 63 is connected to the engaging claw 65d. By engaging, the upper float 65 is pulled down, the valve body 67 is separated from the seal portion 32b, and the connection passage 32a is opened. Thus, the upper float 65 opens with a small force by setting the passage area of the communication hole 65b to be smaller than the passage area of the connection passage 32a. Such a two-stage valve structure using the upper float 65 functions to promote the improvement of the restart valve characteristics.

(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 and reaches the fuel level that closes the introduction opening 57c, the passage forming member 50 increases the tank internal pressure, Due to the pressure difference from the inside of the chamber 20S, the fuel flows into the valve chamber 20S through the introduction passage 50P, so that an auto-stop for stopping the fueling 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. 7, 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 inclination of FT, until the fuel level reaches the full tank level FL1, no fuel enters the valve chamber 20S of the fuel cutoff valve 10 and the float mechanism 60 does not rise. A constant liquid level can be set. In addition, 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 position of the communication hole 35c at the lower end of the casing body 30 of the fuel cutoff valve 10, and the dead space of the fuel tank FT can be increased. It can be reduced and 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 arranged inside the fuel tank, and the fuel The space in the 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, since the internal pressure of the tank does not increase so much except during refueling, the siphon action is not induced and fuel is not guided to the valve chamber 20S, so that the fuel shut-off valve 10 does not cause an unexpected valve closing operation.

  FIG. 8 is a 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 configuration of the casing body 30B and the passage forming member 50B. That is, the inner case 34B constituting the bottom member 35B having the communication hole 35Bc is disposed in the casing main body 30B of the fuel cutoff valve 10B, and the communication pipe 33B is formed in the lower portion of the casing main body 30B. In the passage forming member 50B, one end of the connection pipe 52B constituting the first passage forming part 51B is connected to the communication pipe 33B. The connecting pipe 52B is bent upward and has the other end connected to the joint member 54B welded to the upper part of the fuel tank FT. As described above, the first passage forming portion 51B of the passage forming member 50B may be configured separately from the casing body 30B as long as the position of the introduction opening 57Bc of the third passage forming portion 56B can be appropriately changed.

  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. For example, by providing a discharge valve such as an umbrella valve made of rubber in the discharge hole in the above embodiment, the air tightness of the introduction passage when the introduction opening 57c is blocked with fuel is increased and the inside of the valve chamber or the passage formation member is increased. The fuel may be easily discharged.

DESCRIPTION OF SYMBOLS 10 ... Fuel cutoff valve 10B ... Fuel cutoff valve 20 ... Casing 20S ... Valve chamber 30 ... Casing main body 30B ... Casing main body 31 ... Side wall part 31a ... Flange 32 ... Upper wall part 32a ... Connection passage 32b ... Sealing part 32c ... Barrier wall 33B ... Communication pipe 34B ... Inner case 35 ... Bottom member 35B ... Bottom member 35a ... Bottom main body 35b ... Welding portion 35c ... Communication hole 35Bc ... Communication hole 40 ... Lid body 41 ... Lid main body 41a ... Inner weld portion 42 ... Tube body portion 42a ... Pipe passage 43 ... Flange 43a ... Welding portion 50 ... Passage forming member 50B ... Passage forming member 50P ... Introduction passage 51 ... First passage forming portion 51B ... First passage forming portion 51P ... First passage 51Pa ... Lower chamber 51Pb ... Vertical passage 52 ... Lower passage forming member 52B ... Connecting pipe 52a ... Bottom member 52b ... Outer peripheral wall 52c ... Connecting part 52d ... Welding part 52e ... Outlet 53 ... Derivation passage forming member 53b ... External connection portion 54B ... Joint member 54b ... Connection portion 55 ... Second passage formation portion 55P ... Second passage 56 ... Third passage formation portion 56B ... Third passage formation portion 56P ... First 3 passages 57: pipe main body 57a ... connection part 57b ... introduction pipe 57c ... introduction opening 57Bc ... introduction opening 58 ... welding part 60 ... float mechanism 61 ... float 61S ... buoyancy chamber 61a ... valve part 62 ... float body 62a ... guide protrusion 63 ... collar 65 ... upper float 65a ... disc 65b ... communication hole 65c ... seal part 65d ... engagement claw 67 ... valve element 68 ... spring FT ... fuel tank FTa ... tank upper wall FTb ... mounting hole

Claims (3)

The fuel tank (FT) is mounted in a state where a part thereof is inserted into the upper mounting hole (FTb) of the fuel tank (FT), and fuel is opened and closed by opening and closing the connection passage (32a) connecting the inside of the fuel tank (FT) and the outside. In the fuel cutoff valve that cuts off the communication between the tank (FT) and the external passage,
It has a cylindrical casing body (30) and a bottom member (35) arranged at the lower part of the casing body (30), and the casing body (30) and the bottom member (35) provide a valve chamber ( 20S) and a casing (20) having a communication hole (35c) formed in the bottom member (35),
Supported by the bottom member (35) and housed in the valve chamber (20S), the fuel liquid level in the valve chamber (20S) rises when it reaches the valve closing liquid level (h1), and the connection A float mechanism (60) for closing the passage (32a);
The fuel tank (FT) has an introduction passage (50P) for guiding the fuel to the valve chamber (20S). One of the introduction passages (50P) is connected to the communication hole (35c), and the other is a fuel tank ( A passage forming member (50) having an introduction opening (57c) opened in FT);
With
The casing main body (30) and the passage forming member (50) are configured such that when the fuel liquid level reaches the fuel liquid level closing the introduction opening (57c), the tank internal pressure of the fuel tank (FT) and the valve chamber ( 20S), the fuel is guided to the valve chamber (20S) through the introduction passage (50P) and the communication hole (35c) by the pressure difference from the pressure of the pressure passage 20S), and the float mechanism (60) is raised to connect the passage (32a). Closed is configured in an airtight state,
The passage forming member (50) is bent out so as to be led out of the fuel tank (FT) and into the fuel tank (FT) to form the introduction opening (57c). A discharge hole (52e) is formed in the lowermost part of the passage forming member (50) and in the fuel tank (FT);
A fuel shut-off valve characterized by The fuel cutoff valve according to claim 1,
The casing (20) has a lid (40) that can be attached from the outside of the fuel tank (FT) and is assembled to the casing body (30).
The passage forming member (50) is disposed outside the fuel tank (FT) from the communication hole (35c) along the side wall (31) of the casing body (30) and through the lid (40). and connection portions (5 3 b) first passage forming component with (51), the second passage forming component for forming a top position passage is connected to the first passage forming component (51) and (55), the A fuel cutoff valve having a third passage formation portion (56) connected to the second passage formation portion (55) and entering the fuel tank (FT) in a sealed state and having the introduction opening (57c) . The fuel cutoff valve according to claim 1,
The passage forming member (50B) is a fuel cutoff valve led out of the fuel tank in a state of being sealed by a joint member (54B) fixed to the tank upper wall (FTa) of the fuel tank (FT).

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