JP2019027326A - Fuel shut-off valve - Google Patents

Abstract

To provide a fuel shut-off valve having a wide flow range, high durability, and a great valve opening differential pressure.SOLUTION: A fuel shut-off valve 20 includes a variable opening valve 30, and a float valve 40. The variable opening valve 30 has a movable member 31. The movable member 31 moves according to a flow amount. The float valve 40 has a float member 41. The float member 41 moves according to a fuel liquid surface. Between the variable opening valve 30 and the float valve 40, an interlock mechanism 50 is provided. The interlock mechanism 50 gives the load of the movable member 31 to the float member 41 when the float valve 40 is closed. The load of the movable member 31 produces a greater valve opening differential pressure in the float valve 40.SELECTED DRAWING: Figure 2

Description

  The disclosure herein relates to a fuel shut-off valve.

  One fuel shut-off valve is disclosed in Patent Document 1. The fuel cutoff valve may be called by various names such as a fuel outflow prevention valve, a liquid level detection valve, a rollover valve, and a full tank control valve. In any case, the fuel outflow prevention valve is provided in the vapor processing apparatus and prevents the liquid fuel from flowing out from the fuel tank. The contents of the prior art documents listed as the prior art are incorporated by reference as an explanation of the technical elements in this specification.

JP 2008-149811 A

  In the prior art configuration, if the valve is closed, the differential pressure across the front and back may prevent the valve from opening. For example, when the fuel tank side becomes high pressure and the canister side becomes low pressure, the pressure acts in the direction of closing the valve. For this reason, the high pressure in the fuel tank may not be released.

  In another aspect, the valve defines an opening area when the valve is opened. Therefore, in order to realize a large flow rate, a valve with a large opening is required. However, since a valve with a large opening receives a large force from the differential pressure, it is greatly affected by the differential pressure when the valve is opened.

  Furthermore, from another viewpoint, the heavy valve suppresses the influence of the differential pressure and ensures the valve opening by its own weight. However, heavy valves promote wear and impair durability.

  In view of the above, or other aspects not mentioned, there is a need for further improvements in fuel shut-off valves.

  One disclosed object is to provide a fuel cutoff valve capable of realizing a wide flow range ranging from a small flow rate to a large flow rate.

  Another object of the present disclosure is to provide a fuel cutoff valve that suppresses the influence of differential pressure.

  Yet another object disclosed is to provide a fuel shut-off valve having a wide flow range, high durability, and a large valve-openable differential pressure.

  The fuel cutoff valve disclosed herein includes a float valve (40) that opens and closes a vapor passage (16) in accordance with the level of liquid fuel in a tank (12), and a vapor passage in accordance with the flow rate of fluid in the vapor passage. A variable opening valve (30) that adjusts the opening area of the valve, and an interlocking mechanism that causes the load of the variable opening valve to act on the float valve in the direction in which the float valve opens at least at the closed position where the float valve closes the vapor passage ( 50).

  According to the disclosed fuel cutoff valve, the opening area of the vapor passage is adjusted by the variable opening valve. For this reason, a passage according to the flow rate is provided. A wide flow range from small flow to large flow can be realized. Furthermore, the interlocking mechanism applies the load of the variable opening valve to the float valve. In addition, when the float valve closes the vapor passage, the load of the variable opening valve is applied to the float valve. The direction is the direction in which the float valve opens. Therefore, at least in the valve closing position, the force in the valve opening direction acting on the float valve increases. Even if the pressure difference acts when the float valve is in the closed position, the force against it can be compensated. As a result, the openable differential pressure of the float valve can be increased.

  The disclosed embodiments of the present specification employ different technical means to achieve each purpose. The reference numerals in parentheses described in the claims and this section exemplify the correspondence with the embodiments described later, and are not intended to limit the technical scope. The objects, features, and advantages disclosed in this specification will become more apparent with reference to the following detailed description and accompanying drawings.

It is a block diagram of the system of a 1st embodiment. It is a schematic diagram of a fuel cutoff valve. It is sectional drawing which shows the 1st valve opening state of a fuel cutoff valve. It is sectional drawing which shows the 2nd valve opening state of a fuel cutoff valve. It is sectional drawing which shows the cutoff state of a fuel cutoff valve. It is sectional drawing which shows the valve closing state of a fuel cutoff valve. It is sectional drawing which shows the overturning state of a fuel cutoff valve. It is sectional drawing which shows the cutoff valve of 2nd Embodiment.

  A plurality of embodiments will be described with reference to the drawings. In embodiments, functionally and / or structurally corresponding parts and / or associated parts may be assigned the same reference signs or reference signs that differ by more than a hundred. For the corresponding parts and / or associated parts, the description of other embodiments can be referred to.

First Embodiment <Tank System>
In FIG. 1, a tank system 10 includes a tank 12 that stores fuel for an engine (ICE) 11. The engine 11 is a power source for vehicles such as vehicles, ships, and aircraft. The tank system 10 is, for example, a vehicle tank system. In this case, the engine 11 is provided by an internal combustion engine. The fuel is supplied to the engine 11 as a liquid. However, the fuel may generate vapor (fuel vapor). The fuel is gasoline or diesel fuel.

  The tank system 10 includes a fuel supply device (FLSD) 14 between the engine 11 and the tank 12. The fuel supply device 14 can include an in-tank pump, a fuel filter, a fuel injection pump, and a fuel injection valve. The fuel in the tank 12 is supplied to the engine 11 by the fuel supply device 14. The engine 11 provides power by burning fuel.

  The tank system 10 includes a vapor purification device (VPCD) 15. The vapor purification device 15 burns by supplying vapor to the engine 11. The vapor purification device 15 suppresses the discharge of vapor to the atmosphere. The vapor purification device 15 includes an accumulator that temporarily accumulates vapor and a controller that supplies the accumulated vapor to the engine 11 at a predetermined timing. For example, the accumulator is provided by activated carbon that adsorbs vapor. Further, the controller is provided by an electric control device and a valve for introducing outside air for flushing.

  The vapor purification device 15 has a vapor passage 16 that communicates the cavity in the tank 12 with the accumulator. The vapor passage 16 guides the vapor generated in the tank 12 to the vapor purification device 15. The vapor passage 16 is also a passage for supplying outside air to the tank 12. The vapor passage 16 extends from the tank 12.

  The vapor purification device 15 has a fuel cutoff valve 20. The fuel shut-off valve 20 allows vapor and air to flow. The fuel cutoff valve 20 suppresses the outflow of the fuel liquid from the tank 12 to the vapor purification device 15. The fuel cutoff valve 20 is provided in the vapor passage 16. The fuel cutoff valve 20 is fixed to the tank 12. The fuel cutoff valve 20 is fixed to the flange 17 of the tank 12. The flange 17 is a lid that occupies a part of the upper surface of the tank 12.

<Fuel shut-off valve>
In FIG. 2, the normal posture of the fuel cutoff valve 20 is shown. In the following description, terms such as up, down, up direction UP, and down direction DW are based on regular postures. The terms down and down DW refer to the direction of gravity. The fuel cutoff valve 20 is also called a float valve, a liquid level detection valve, or a rollover valve. The fuel shut-off valve 20 has a plurality of parts that are resin molded products. Some parts are made of elastic rubber or metal that provides the required strength.

  The fuel cutoff valve 20 provides a part of the vapor passage 16 with a case 21. The case 21 provides a passage that connects the inside of the tank 12 and the outside of the tank 12. The case 21 is provided by a plurality of members. These members are resin molded products. The case 21 has a first opening 22 that communicates with the vapor purification device 15 side and a second opening 23 that communicates with the tank 12 side. The case 21 defines a float chamber 24, a main port 25, and an outer gallery 26 in order from the tank 12 side between the first opening 22 and the second opening 23. The float chamber 24 is positioned so as to protrude into the tank 12. The float chamber 24 is formed such that liquid fuel enters the float chamber 24 when the fuel in the tank 12 approaches the upper limit. The float chamber 24 accommodates a float described later. The main port 25 is a main through hole that communicates the inside and outside of the tank 12. The main port 25 has a relatively large opening area that allows the maximum flow rate allowed by the fuel cutoff valve 20. The case 21 defines a main port 25 that provides the vapor passage 16. The outer gallery 26 is a cavity for accommodating a variable opening valve 30 described later. The outer gallery 26 is also a cavity for capturing liquid fuel and returning it to the tank 12.

<Variable opening valve>
The fuel cutoff valve 20 has a variable opening valve 30. The variable opening valve 30 is provided above the main port 25. The variable opening valve 30 changes the opening area in proportion to the flow rate. The variable opening valve 30 can also be called a flow rate sensing valve that adjusts the opening of the flow path according to the flow rate. The variable opening valve 30 provides a small opening area limited when the flow rate is small, and provides a large opening area when the flow rate is larger than the small flow rate. The variable opening valve 30 is a proportional flow rate sensing valve.

  The variable opening valve 30 has a movable member 31. The movable member 31 is movable along the axis AX of the fuel cutoff valve 20. The direction of the axis AX is the vertical direction in the normal posture of the fuel cutoff valve 20. The movable member 31 has a core 32 and a seal member 33. The core 32 is a cup-shaped member. The seal member 33 is a rubber plate-like member. The seal member 33 is fixed to the core 32. The movable member 31 is positioned so that the seal member 33 opens and closes the main port 25. Around the main port 25, a seat 34 that contacts or leaves the seal member 33 is provided. The movable member 31 contacts the seat 34 when the flow rate is a small flow rate, and moves away from the seat 34 when the flow rate is a large flow rate larger than the small flow rate, and adjusts the opening area to a large area. The seat 34 is provided on the upper side of the main port 25. The sealing member 33 provides high sealing performance.

  The movable member 31 has a sub port 35. The sub port 35 is a through hole that penetrates the movable member 31. The sub port 35 communicates the main port 25 and the outer gallery 26. The sub port 35 communicates even when the main port 25 is closed by the seal member 33 contacting the seat 34. The sub port 35 defines an opening area when the movable member 31 is in contact with the sheet 34. The main port 25 provides an opening area corresponding to a large flow rate required for the fuel cutoff valve 20. The sub port 35 provides an opening area corresponding to a small flow rate required near the boundary (cutoff) between the opening and closing of the fuel cutoff valve 20. The sectional area of the sub port 35 is smaller than the sectional area of the main port 25. The variable opening valve 30 includes a spring 36 that urges the movable member 31 in the downward direction DW. The spring 36 is compressed. The movable member 31 is guided by a guide member 37. The guide member 37 extends from the case 21. The guide member 37 is integrally formed of a resin material continuous with the case 21.

  The flow rate of the fluid from the tank 12 toward the vapor passage 16 (mixed fluid of air, vapor, and a small amount of liquid fuel) varies depending on the difference between the pressure in the tank 12 and the pressure in the vapor passage 16. For example, when the tank 12 is hot and the vapor is sucked into the engine 11, a large flow rate of fluid flows. On the other hand, when the tank 12 is at a low temperature and the engine 11 does not suck the vapor, a small flow rate of fluid flows.

  When the flow rate from the tank 12 toward the vapor passage 16 is large, the movable member 31 moves away from the seat 34. At this time, the movable member 31 and the seat 34 provide an opening area larger than the main port 25. The opening area of the passage provided by the fuel cutoff valve 20 is governed by the opening area of the main port 25. The opening area of the main port 25 defines the maximum flow rate of the passage provided by the fuel cutoff valve 20.

  When the flow rate from the tank 12 toward the vapor passage 16 is small, the movable member 31 is seated on the seat 34. At this time, the sub port 35 provides a smaller opening area than the main port 25. The opening area of the passage provided by the fuel cutoff valve 20 is governed by the opening area of the sub port 35. The opening area of the sub port 35 limits the flow rate of the passage provided by the fuel cutoff valve 20.

<Float valve>
The fuel cutoff valve 20 has a float valve 40. The float valve 40 is provided below the main port 25. The float valve 40 is also referred to as a liquid level detection valve that opens and closes the vapor passage 16 in accordance with the fuel level in the tank 12. The float valve 40 opens and closes the main port 25 in accordance with whether or not the fuel liquid level is lower than the first liquid level FL1. The first liquid level corresponds to a full tank 12. The float valve 40 opens and closes the sub port 35 in accordance with whether or not the fuel liquid level is lower than the second liquid level FL2. The float valve 40 opens and closes the main port 25, that is, the vapor passage 16 indirectly by opening and closing the sub port 35. The first liquid level FL1 corresponds to a full tank 12. The second liquid level FL2 is slightly lower than the first liquid level FL1.

  The float valve 40 has a float member 41. The float member 41 has a float core 42 and a float seal 43. The float core 42 floats on the liquid fuel. On the other hand, when the tank 12 rolls over, the float core 42 sinks into the liquid fuel. The float valve 40 includes a float spring 45 that biases the float core 42 in the upward direction UP. The float spring 45 is compressed. The float valve 40 may include an air chamber formed in the float core 42 in order to impart such characteristics to the float core 42. The float core 42 is a cap-shaped member having an air chamber. The float seal 43 is a rubber plate member. The float seal 43 is fixed to the float core 42. The float seal 43 may be supported so as to be slightly movable with respect to the float core 42. The float member 41 is positioned so that the float seal 43 opens and closes the main port 25. Around the main port 25, a float sheet 44 that contacts or leaves the float seal 43 is provided. The float sheet 44 is provided below the main port 25. The float member 41 comes into contact with the float sheet 44 by floating on the liquid surface and closes the main port 25. The float seal 43 provides high sealing performance. The float member 41 is movable in the vertical direction when the tank 12 is in a normal posture. The movable member 31 is movable along the moving direction of the float member 41.

<Interlocking mechanism>
The fuel cutoff valve 20 has an interlocking mechanism 50. The interlock mechanism 50 causes the load of the variable opening valve 30 to act on the float valve 40 in a direction in which the float valve 40 opens at least at the valve closing position where the float valve 40 closes the vapor passage 16. The interlocking mechanism 50 is also called a liquid level detection valve that opens and closes the sub port 35 in accordance with the fuel level in the tank 12. However, the interlocking mechanism 50 allows the sub port 35 to be opened and closed by the float core 42. Furthermore, the interlocking mechanism 50 can open and close two ports by one float core 42.

  The interlocking mechanism 50 includes a connecting rod 51 and a valve body 52. The connecting rod 51 is shaped by a resin material continuous with the float core 42. The connecting rod 51 and the float core 42 are integral. The connecting rod extends along the moving direction of the movable member 31 and the float member 41. The connecting rod 51 can be inserted into the main port 25. The connecting rod 51 has a length protruding from both ends of the main port 25. A valve body 52 is provided at the tip of the connecting rod 51 by integral shaping of a resin material. The valve body 52 can contact the movable member 31 to close the sub port 35. The valve body 52 provides a small area that is not easily affected by the differential pressure. The connecting rod 51 has a length that allows the seal member 33 to be lifted from the seat 34.

  The float valve 40 and the interlocking mechanism 50 open and close the sub port 35 at the second liquid level FL2 lower than the first liquid level FL1. The float valve 40 and the interlocking mechanism 50 open and close the sub port 35 in accordance with whether or not the fuel liquid level is lower than the second liquid level FL2. The second liquid level corresponds to the boundary liquid level at which the fuel cutoff valve 20 should be closed. This liquid level is also called a cutoff liquid level. The difference between the first liquid level FL1 and the second liquid level FL2 is very small. For this reason, both may be called cut-off liquid levels.

  The interlocking mechanism 50 gives relevance to the opening / closing characteristics of the variable opening valve 30 and the float valve 40. The interlocking mechanism 50 allows the movable member 31 to freely move when the fuel liquid level is lower than the second liquid level FL2. The interlock mechanism 50 closes the main port 25 when the fuel level exceeds the first level FL1. The interlocking mechanism 50 forcibly separates the movable member 31 from the seat 34 by lifting the movable member 31 when the fuel liquid level is between the first liquid level FL1 and the second liquid level FL2. The connecting rod 51 extends from the float member 41 and lifts the movable member 31 when the float member 41 closes the main port 25. As a result, the interlocking mechanism 50 causes the load acting on the movable member 31 to act directly on the float core 42. In the embodiment, the weight of the movable member 31 and the urging force of the spring 36 act on the float member 41 in the downward direction DW.

<Operation>
In FIG. 2, the variable opening valve 30 moves according to its own weight M31 of the movable member 31, an urging force S36 by the spring 36, and a drag D31 received from the gas flowing through the passage. The drag D31 changes according to the flow rate. When the tank 12 is in the normal posture, the drag D31 changes from a minimum value (D31 <M31 + S36) smaller than the sum of the own weight M31 and the urging force S36 to a maximum value larger than the sum of the own weight M31 and the urging force S36. (M31 + S36 <D31). The urging force S36 is larger than its own weight M31 (M31 <S36). Thereby, when the tank 12 is overturned, the spring 36 can move the movable member 31 toward the seat 34.

  FIG. 3 shows a first valve open state in which the variable opening valve 30 is closed and the float valve 40 is open. This state can also be referred to as a ground state. At this time, the flow rate of the gas flowing through the vapor passage 16 is a sufficiently small flow rate at the sub port 35.

  In the illustrated example, the case 21 is provided by a main case 21a and a cap 21b. The main case 21a is a cylindrical container mainly for housing the float valve 40. The cap 21b is fixed to the main case 21a by a snap fit. The cap 21 b provides a seating surface for the spring 36. The variable opening valve 30 is attached to the main case 21a. Thereby, the fuel cutoff valve 20 can be handled as one component. An O-ring as a seal member 21c is provided between the main case 21a and the flange 17.

  On the radially outer side of the cylindrical portion that provides the main port 25, an annular partition plate 21d extends. The partition plate 21d is a dish-like member with the main port 25 positioned at the center. The partition plate 21 d is located on the radially outer side than the variable opening valve 30. When the tank 12 is in the normal posture, the partition plate 21 d provides a slope with a slightly recessed center around the variable opening valve 30. The partition plate 21 d provides an annular inclined surface inclined toward the central main port 25 on the radially outer side of the variable opening valve 30. Further, the slope provided by the partition plate 21d provides a continuous downward slope to the vicinity of the sheet 34. Liquid fuel may leak through the variable opening valve 30. In this case, the liquid fuel flows on the partition plate 21d and returns to the tank 12 from the main port 25 again.

  FIG. 4 shows a second valve open state in which the variable opening valve 30 is open and the float valve 40 is open. This state can also be referred to as a large flow rate state. At this time, the flow rate of the gas flowing through the vapor passage 16 is insufficient at the sub port 35 and is a large flow rate that requires the main port 25. A large flow rate state may occur, for example, when a large amount of vapor is generated when the tank 12 is hot.

  Returning to FIG. 2, the float valve 40 opens and closes the sub port 35 at the first liquid level FL1, and opens and closes the main port 25 at the second liquid level FL2. The float valve 40 moves according to its own weight M41 of the float member 41, the urging force S45 of the float spring 45, and the buoyancy F41 of the float member 41 (mainly the buoyancy of the float core 42). Further, when the float member 41 and the movable member 31 are in contact with each other by the interlocking mechanism 50, the own weight M <b> 31 of the movable member 31 and the biasing force S <b> 36 of the spring 36 act on the float member 41 via the interlocking mechanism 50. This force urges the float member 41 in the downward direction DW, that is, in the valve opening direction.

  The second liquid level FL2 is called a cutoff liquid level where the vapor passage 16 is desired to be closed. The valve body 52 opens and closes the sub port 35 in accordance with whether or not the fuel liquid level exceeds the second liquid level FL2. At this time, the force CL2 that moves the float member 41 in the upward direction, that is, the valve closing direction is CL2 = F41 + S45-M41. This force CL2 is smaller than the force (M31 + S36) for moving the movable member 31 in the valve closing direction (CL2 <M31 + S36). As a result, in the vicinity of the second liquid level FL2, the sub port 35 is opened and closed in response to the fuel level. At this time, the sealing area between the valve body 52 and the sub port 35 is small. This seal area is at least smaller than the main port 25. For this reason, even if a pressure difference acts, the valve body 52 can be separated from the seal member 33 relatively easily. As a result, the sub port 35 is smoothly opened and closed.

  FIG. 5 shows a cutoff state of the fuel cutoff valve 20. The variable opening valve 30 is closed, and the float valve 40 closes the sub port 35 through the interlock mechanism 50. The float valve 40 and the interlocking mechanism 50 open the sub port 35 when the fuel liquid level falls below the second liquid level FL2 lower than the first liquid level FL1, and the sub port 35 when the fuel liquid level exceeds the second liquid level FL2. Close.

  Returning to FIG. 2, when the fuel liquid level exceeds the second liquid level FL <b> 2 and reaches the first liquid level FL <b> 1, the interlocking mechanism 50 lifts the movable member 31. For example, if the tank 12 shakes in the vicinity of the second liquid level FL2, the liquid level of the fuel may temporarily exceed the first liquid level FL1 due to the undulation of the liquid fuel. At this time, the force CL1 that moves the float member 41 upward, that is, in the valve closing direction, is CL1 = F41 + S45-M41. This force CL1 is larger than the force (M31 + S36) for moving the movable member 31 in the valve closing direction (M31 + S36 <CL1). The force CL1 is greater than the force CL2 (CL2 <CL1). This difference is a difference in buoyancy F41 generated in the float core 42. In this case, the movable member 31 is separated from the seat 34, but at the same time, the float member 41 is seated on the float seat 44 to close the main port 25. As a result, the closed state of the vapor passage 16 is maintained.

  FIG. 6 shows the closed state of the fuel cutoff valve 20. The main port 25 is closed when the float seal 43 is seated on the float seat 44. The float valve 40 opens the main port 25 when the fuel liquid level falls below a predetermined first liquid level FL1, and closes the main port 25 when the fuel liquid level exceeds the first liquid level FL1. At this time, the movable member 31 and the spring 36 push the float member 41 downward, that is, in the valve opening direction.

  Returning to FIG. 2, when the fuel level in the tank falls, the float member 41 loses buoyancy and opens the main port 25 and the subport 35 by its own weight M41. If the pressure difference acts when the float member 41 and the float sheet 44 are in contact, the float member 41 may stick to the float sheet 44. In this case, the float member 41 cannot be opened while the pressure on the tank 12 side is high. The pressure that can be opened is a low pressure. However, according to this embodiment, the dead weight M31 of the movable member 31 and the biasing force S36 of the spring 36 act so as to push down the float member 41 through the interlocking mechanism 50. In other words, a force for shifting the float member 41 from the closed state to the open state is applied only at the initial stage of opening the valve. For this reason, even if a pressure difference acts on the float member 41, the float member 41 can be opened. Therefore, the fuel cutoff valve 20 having a high valve opening possible differential pressure is provided.

  When the tank 12 is in the capsized position, the float core 42 loses most of the buoyancy. The float member 41 moves to the valve closing position by its own weight M41 and the urging force S36, and presses the float seal 43 and the float seat 44. As a result, the main port 25 is closed. The sum of the own weight M41 of the float member 41 and the urging force S45 of the float spring 45 is larger than the difference between the urging force S36 of the spring 36 and the own weight M31 of the movable member 31 (S36−M31 <M41 + S45). Thereby, even if the variable opening valve 30 acts in the valve opening direction in the vicinity of the valve closing position of the float valve 40, the valve closing function is reliably provided. At this time, the float seal 43 provides excellent sealing performance over a long period of time.

  FIG. 7 shows the state of the fuel cutoff valve 20 when the tank 12 is in the capsized position. The main port 25 is closed when the float seal 43 is seated on the float seat 44.

Second Embodiment This embodiment is a modified example based on the preceding embodiment. In the above embodiment, the variable opening valve 30 is attached to the main case 21a. Instead, in this embodiment, the variable opening valve 30 is disposed between the flange 17 and the main case 21a.

  FIG. 8 shows the fuel cutoff valve 20 of this embodiment. The variable opening valve 30 has a seat 34 formed on the main case 21a. The movable member 31 is guided in the axial direction by a guide member 237 extending from the flange 17. The guide member 237 also provides a seat for the spring 36.

Other Embodiments The disclosure herein is not limited to the illustrated embodiments. The disclosure encompasses the illustrated embodiments and variations by those skilled in the art based thereon. For example, the disclosure is not limited to the combinations of parts and / or elements shown in the embodiments. The disclosure can be implemented in various combinations. The disclosure may have additional parts that can be added to the embodiments. The disclosure includes those in which parts and / or elements of the embodiments are omitted. The disclosure encompasses the replacement or combination of parts and / or elements between one embodiment and another. The technical scope disclosed is not limited to the description of the embodiments. The several technical scopes disclosed are indicated by the description of the claims, and should be understood to include all modifications within the meaning and scope equivalent to the description of the claims.

  In the above embodiment, the interlocking mechanism 50 has the connecting rod 51 on the float core 42. Instead of this, a connecting rod for the interlock mechanism 50 may be provided on the movable member 31 of the variable opening valve 30. In this embodiment, the sub port 35 is opened and closed by the valve body 52. It can replace with this and the structure which is not provided with the valve body 52 is employable. In this case, the first liquid level FL1 where the float seal 43 is seated on the float sheet 44 may be the cut-off liquid level.

10 tank systems, 11 engines, 12 tanks,
14 fuel supply device, 15 vapor purification device,
16 vapor passage, 17 flange,
20 Fuel shut-off valve, 21 case, 21a Main case,
21b cap, 21c sealing member, 21d partition plate,
22 1st opening, 23 2nd opening, 24 float chamber,
25 main port, 26 outside gallery,
30 variable opening valve, 31 movable member, 32 core,
33 sealing member, 34 sheet, 35 secondary port,
36 spring, 37 guide member,
40 float valve, 41 float member,
42 float core, 43 float seal,
44 float seat, 45 float spring,
50 interlocking mechanism, 51 connecting rod, 52 disc,
237 guide member,
AX central axis, FL1 first liquid level, FL2 second liquid level,
UP upward, DW downward.

Claims (10)

A float valve (40) for opening and closing the vapor passage (16) according to the liquid level of the liquid fuel in the tank (12);
A variable opening valve (30) for adjusting an opening area of the vapor passage according to a flow rate of fluid in the vapor passage;
A fuel cutoff valve comprising: an interlock mechanism (50) that applies a load of the variable opening valve to the float valve in a direction in which the float valve opens in at least a closed position where the float valve closes the vapor passage. A case (21) defining a main port (25) for providing the vapor passage;
The float valve is provided below the main port;
The variable opening valve is provided on the upper side of the main port,
The fuel cutoff valve according to claim 1, wherein the interlocking mechanism includes a connecting rod (51) inserted into the main port. The float valve includes a float sheet (44) provided on the lower side of the main port, and a float member (41) that comes into contact with the float sheet and closes the main port by floating on the liquid surface. ,
The variable opening valve is in contact with the seat (34) provided on the upper side of the main port and the seat when the flow rate is a small flow rate, and when the flow rate is a large flow rate larger than the small flow rate. A movable member (31) for adjusting the opening area away from the sheet,
The fuel cutoff valve according to claim 2, wherein the connecting rod extends from the float member, and lifts the movable member when the float member closes the main port. The float member is movable in a vertical direction when the tank is in a normal posture,
The movable member is movable along the movement direction of the float member,
The fuel cutoff valve according to claim 3, wherein the connecting rod extends along the moving direction.   The fuel cutoff valve according to claim 3 or 4, wherein the variable opening valve includes a guide member (37, 237) for guiding the movable member. The movable member has a subport (35) that defines the opening area when in contact with the sheet;
The said interlocking mechanism is a fuel cutoff valve in any one of Claims 3-5 provided with the valve body (52) which opens and closes the said subport at the front-end | tip of the said connection rod.   The fuel cutoff valve according to claim 6, wherein the sub port is smaller than the main port. The float valve opens the main port when the fuel liquid level falls below a predetermined first liquid level (FL1), and closes the main port when the fuel liquid level exceeds the first liquid level,
The float valve and the interlock mechanism open the subport when the fuel level falls below a second level (FL2) lower than the first level, and the fuel level exceeds the second level. The fuel cutoff valve according to claim 6 or 7, wherein the auxiliary port is closed.   The fuel cutoff valve according to any one of claims 2 to 8, wherein the case provides an annular inclined surface that is inclined toward the main port at a center, on a radially outer side of the variable opening valve.   The fuel cutoff valve according to any one of claims 1 to 9, wherein the float valve includes a float seal (43) for opening and closing the vapor passage.

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