JP2009078647A - Fuel shutoff valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel shutoff valve having superior durability and improved sealing performance by using a flexible valve body made of rubber, etc. <P>SOLUTION: The fuel shutoff valve 10 is equipped with a casing 20 and a float mechanism arranged in a valve chamber 20S to be able to rise/fall. The float mechanism comprises a first float 42, a second float 52, and a rubber sheet member 57 mounted to an upper part of the second float 52. A sheet part 57a of the sheet member 57 is bent to a recessed part 53S for bending when it is pressed by a sealing part 45c. The sealing part 45c has a regulation part 46 on its outer peripheral side for regulating an elastic deformation amount of the sheet part 57a to the recessed part 53S for bending. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fuel cutoff valve that is mounted on an upper portion of a fuel tank and that cuts off the communication between the fuel tank and the outside according to the fuel level in the fuel tank.

  Conventionally, as a fuel shut-off valve of this type, the technique of Patent Document 1 is known. That is, the conventional fuel cutoff valve includes a casing having a connection passage connected to the outside of the fuel tank, a cylindrical first float valve disposed in a valve chamber in the casing, and a first float valve in the first float valve. A second float valve disposed in the storage chamber so as to be movable up and down and having a connection hole, and a spring for supporting these, and when the fuel level exceeds the first level, the connection path is defined by the first float valve. When the second liquid level is exceeded, the connection hole of the second float valve is closed. This prevents the fuel from flowing out from the fuel tank to the canister during refueling or when the vehicle swings.

  By the way, in recent years, flattening of fuel tanks has been studied in order to cope with various and large living spaces of vehicles. In such flattened fuel tanks, in order to reduce the proportion of dead space above the fuel tanks. In addition, it is preferable to set the fuel level to be closed as high as possible. However, when the fuel level at the time of closing the valve is set high, the float valve is liable to be submerged. In order to obtain high sealing performance even in the case of such submergence, a means for attaching a rubber valve body to the upper center of the float and elastically deforming the outer periphery of the rubber valve body when the rubber valve body closes the passage is known. ing. However, in order to elastically deform the rubber valve body, it is necessary to reduce the thickness of the rubber valve body itself, but there is a problem that the rubber valve body changes over time due to repeated elastic deformation.

JP 2002-61765 A

  In light of solving the above-described problems of the conventional technology, the present invention has a two-stage float structure that uses a flexible valve body such as rubber to improve the sealing performance and is excellent in durability. The object is to provide a fuel shut-off valve.

  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 includes a casing that forms a valve chamber that is attached to the upper portion of the fuel tank and is connected to the outside of the fuel tank, and a float mechanism that is arranged to be movable up and down in the valve chamber. In the fuel cutoff valve that cuts off the communication between the fuel tank and the outside by raising and lowering the float mechanism according to the liquid level,
The float mechanism is
A first float having a storage chamber opened downward, a connection hole connecting the storage chamber and the valve chamber, and a seal portion provided facing the connection hole and projecting annularly toward the storage chamber; ,
A second float stored in the storage room so as to be movable up and down;
A sheet member interposed between the first float and the upper part of the second float, formed from a flexible material, and having a sheet portion for opening and closing the connection hole;
With
The second float is provided with a bending recess for bending when the sheet portion is pressed by the seal portion at a position on the upper surface of the second float and facing the seal portion.
It has a regulation part which is formed in the 1st float or the 2nd float on the perimeter side of the above-mentioned seal part, and regulates the amount of elastic deformation which the above-mentioned sheet part elastically deforms to the above-mentioned bending recess. .

  The fuel shut-off valve according to Application Example 1 includes a float mechanism in the casing, and the float mechanism moves up and down according to the fuel liquid level to cut off the passage to the outside. Even when the first float blocks the passage to the outside, the second float keeps the connection hole open and ensures ventilation to the outside in the fuel tank when the first float is below the predetermined liquid level. The connection hole is closed by raising the fuel level. In such a valve-closed state, when the flexible sheet member is seated on the seal portion, the portion pressed by the seal portion is elastically deformed toward the bending recess in the upper portion of the second float. Therefore, since the seat portion is elastically deformed so as to be pressed and adhered by the seal portion, high sealing performance can be obtained even when the vehicle is subjected to vibration. Further, in a state where the seat portion is elastically deformed and seated on the seal portion, the upper surface of the seal member hits the restricting portion and the rise of the float is restricted, so that the seat portion is not further extended by the seal portion. In other words, the restricting portion is excellent in durability because the restricting portion does not receive large elastic deformation due to repetition of the seat portion by restricting the elastic deformation amount of the seat portion.

[Application Example 2]
In Application Example 2, a plurality of the restriction portions are arranged in the circumferential direction so as to surround the outer peripheral portion of the seal portion. With this configuration, the contact area between the flexible seal member and the restricting portion is reduced, and sticking or sticking to the seal portion can be prevented.

[Application Example 3]
In Application Example 3, the second float includes a valve support hole in an axis center of the second float, and the seat member includes a seat support portion protruding from the back side of the seat portion. The support part can be configured to be attached to the second float by being inserted into the valve support hole. With this configuration, the sheet member can be easily attached to the second float.

[Application Example 4]
Application Example 4 is configured such that the sheet portion is in contact with the upper surface of the second float. With this configuration, the sheet portion needs to bend toward the bending recess in which a part of the upper surface of the second float is recessed, and it is necessary to provide a gap for bending between the upper surface of the second float and the sheet portion of the sheet member. Therefore, the bulkiness of the float mechanism in the height direction can be eliminated, which can contribute to downsizing. Further, since the seat member is assembled in a stable posture in contact with the upper surface of the second float, the surface accuracy of the seat portion with respect to the seal portion can be increased, and thus the sealing performance can be improved.

[Application Example 5]
Application Example 5 includes a casing that forms a valve chamber that is attached to the upper portion of the fuel tank and is connected to the outside of the fuel tank, and a float mechanism that is arranged to be movable up and down in the valve chamber. In the fuel cutoff valve that cuts off the communication between the fuel tank and the outside by raising and lowering the float mechanism according to the liquid level,
With
The float mechanism is
A first float having a storage chamber that opens downward, and a connection hole that connects the storage chamber and the valve chamber;
A second float that is stored in the storage chamber so as to be movable up and down, and that has a seal portion facing the connection hole and projecting annularly toward the first float;
A sheet member having a sheet portion mounted so as to surround the connection hole of the first float;
With
The first float is provided with a bending recess for bending when the sheet portion is pressed by the seal portion on a lower surface of the first float and facing the seal portion.
It is characterized in that it has a restricting portion that is formed on the outer peripheral side of the seal portion and on the upper surface of the second float and restricts the amount of elastic deformation of the sheet member elastically deforming into the bending recess.
As in Application Example 5, even if the sheet member is provided on the first float side and the restricting portion is provided on the second float side, the same operations and effects as in Application Examples 1 to 4 are obtained.

  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 cutoff valve 10 attached to an upper portion of a fuel tank FT of an automobile according to an embodiment of the present invention. The fuel shut-off valve 10 is a so-called in-tank type that is mounted in the fuel tank FT. When the fuel in the fuel tank FT rises to a predetermined liquid level during refueling or the like, fuel to the outside (canister) is supplied. It is a valve that regulates the outflow. Here, the predetermined liquid level is a first liquid level FL1 that means that the fuel is full when refueling, and a first that regulates the outflow of fuel when the vehicle is tilted or when the vehicle suddenly turns. The second liquid level FL2 is higher than the liquid level FL1. Hereinafter, the configuration and operation of each part of the fuel cutoff valve 10 will be described.

(2) Configuration of Each Part of Fuel Shutoff Valve 10 The fuel cutoff valve 10 includes a casing 20 and a float mechanism, and communicates and shuts off to the outside when the float mechanism is raised and lowered. The float mechanism includes a first float 42 and a first spring 48 that constitute the full tank regulating valve 40, and a second float 52 and a second spring 58 that constitute the rollover valve 50 as main components. A valve mounting portion 20a is formed integrally with the upper portion of the casing 20, and is mounted in the fuel tank FT via a bracket BK welded to the lower surface of the tank upper wall FTa of the fuel tank FT.

(2) -1 Casing 20
FIG. 2 is an exploded sectional view of the fuel cutoff valve. In FIG. 2, the casing 20 includes a casing body 30, an upper lid 35 attached to the upper part of the casing body 30, and a bottom plate 36 attached to the lower part of the casing body 30. The casing body 30 includes a ceiling wall portion 32, a side wall portion 33 extending in a cylindrical shape downward from the ceiling wall portion 32, and a tubular body portion 34 integrally formed on the upper portion of the side wall portion 33. A cup-shaped valve chamber 20 </ b> S surrounded by the ceiling wall portion 32, the side wall portion 33, and the bottom plate 36 is formed, and a lower portion thereof is a lower opening 30 a. A passage forming projection 32a projecting downward is formed at the center of the ceiling wall 32, and a connection passage 32b connected to the valve chamber 20S passes through the passage forming projection 32a. The valve chamber 20S side of the connection passage 32b is an annular seal portion 32c. A vent hole 33a for connecting the inside of the fuel tank FT and the valve chamber 20S is formed in the upper portion of the side wall portion 33, and an engagement recess 33b is formed in the lower portion thereof. The engagement recess 33 b is for attaching the bottom plate 36.

  The tube part 34 is provided so as to project obliquely downward from the upper part of the side wall part 33, and a pipe passage 34a is formed on the inside thereof. The pipe passage 34a is connected to the canister side via a tube (not shown). The upper lid 35 closes the upper opening of the casing body 30 to form a communication chamber 21S. The communication chamber 21S is connected to the valve chamber 20S via the pipe passage 34a and the connection passage 32b. The bottom plate 36 is a member that closes the lower opening 30 a of the casing body 30. By engaging an engaging claw 36 a formed on the outer periphery of the bottom plate 36 with an engaging recess 33 b of the casing body 30, It is mounted so as to close the opening 30a. A communication hole 36 b is formed through the central portion of the bottom plate 36. The communication hole 36b communicates with the inside of the fuel tank and the valve chamber 20S, and allows the fuel to flow into the valve chamber 20S.

(2) -2 Full tank control valve 40
The full tank regulating valve 40 is a valve that determines the fuel level in the fuel tank FT supplied during refueling, and is mainly composed of a first float 42 and a seat member 47 mounted on the upper part of the first float 42. It is said. The 1st float 42 is comprised by the container shape provided with the upper wall part 43 and the cylindrical side wall part 44 formed below from the outer periphery of the upper wall part 43, The inner space is the 2nd float. It is a storage chamber 42 </ b> S for storing 52. Further, a vent hole 44a is formed in the upper portion of the side wall 44 of the first float 42, and the storage chamber 42S communicates with the valve chamber 20S. A guide protrusion 44 b is formed on the outer periphery of the first float 42, and is guided by the side wall 33 of the casing body 30. A valve support member 45 projects from the upper center of the upper wall portion 43. The valve support member 45 has a valve holding recess 45a, and a seat member 47 is attached to the valve holding recess 45a. A connection hole 45 b passes through the valve support member 45. A seal portion 45c is formed on the periphery of the lower opening of the connection hole 45b. The seat member 47 is made of a flexible material (rubber material, thermoplastic elastomer, etc.), and is supported by the valve support member 45 by press-fitting the support base 47a of the seat member 47 into the valve holding recess 45a. The seat portion 47b on the outer peripheral portion of the support base portion 47a opens / closes with the seal portion 32c to open / close the connection passage 32b.

(2) -3 Rollover valve 50
FIG. 3 is an exploded perspective view of the rollover valve 50. The rollover valve 50 is a valve for preventing the fuel in the fuel tank from leaking outside when the vehicle falls, and the second float 52 and the seat member 57 mounted on the upper part of the second float 52. And. The 2nd float 52 is comprised by the container shape provided with the upper side wall part 53 and the cylindrical side wall part 54 formed below from the outer periphery of the upper wall part 53, The inner space produces buoyancy. This is a float chamber 52S (FIG. 2). A guide protrusion 54 a is formed on the outer periphery of the second float 52. The guide ridges 54a are provided on the side wall portion 54 of the second float 52 so as to protrude in a rib shape in the vertical direction at eight locations in the circumferential direction. The guide protrusion 54a guides the wall surface of the storage chamber 42S (FIG. 2) of the first float 42.

  The sheet member 57 is made of a flexible material (rubber material, thermoplastic elastomer, etc.), and has a disk-like sheet portion 57a and a sheet support projecting in a rod shape from the lower center of the sheet portion 57a. And a retaining portion 57c formed in the middle of the seat support portion 57b. The seat support portion 57b is press-fitted into the valve support hole 53a, and is engaged with the peripheral edge portion of the valve support hole 53a by the retaining portion 57c. Is attached to the upper part of the second float 52. A second spring 58 is disposed in the float chamber 52S of the second float 52 shown in FIG. The second spring 58 urges the second float 52 upward by being interposed between one end of the second float 52 and the spring support portion 36 c of the bottom plate 36.

(2) -4 Deflection Control Mechanism FIG. 4 is an enlarged cross-sectional view of the upper portions of the first float 42 and the second float 52. 3 and 4, a mechanism is provided around the seal portion 45c and the sheet member 57 of the first float 42 to bend the flexible sheet member 57 and to restrict the amount of bending to a predetermined amount or less. ing. That is, a bending recess 53 </ b> S is formed in the upper part of the second float 52. The bending recess 53S is a position facing the seal portion 45c, and is formed to bend when the sheet portion 57a is pressed by the seal portion 45c. Here, the width of the bending recess 53S is such that even when the first float 42 and the second float 52 are relatively inclined, one end portion of the sheet portion 57a that first contacts the seal portion 45c of the sheet portion 57a is bent. It is formed so that it can be bent into the recess 53S (see FIG. 4). Further, as shown in FIG. 3, the drainage liquid that facilitates the bending of the sheet member 57 by discharging the fuel accumulated in the bending recess 53S at three locations in the circumferential direction at the outer periphery of the bending recess 53S. A groove 53Sa is formed.

  FIG. 5 is a view of the lower surface of the upper wall portion 43 of the first float 42 as viewed from below. A restricting portion 46 for restricting the amount of bending of the seat portion 57a is formed on the lower surface of the upper wall portion 43 and on the outer periphery of the seal portion 45c. The restricting portion 46 is divided into a plurality of parts (eight places in FIG. 5) and arranged in an annular shape, and the elastic deformation amount of the sheet portion 57a is caused when the restricting portion 46 hits the outer peripheral portion of the sheet member 57 as shown in FIG. Is regulated.

(3) Operation at the time of refueling of the fuel cutoff valve 10 (3) -1 Refueling operation Next, the operation of the fuel cutoff valve 10 will be described. When fuel is supplied to the fuel tank FT by a fuel gun (not shown) from the opened state of the fuel shut-off valve 10 shown in FIG. 1, the fuel vapor accumulated in the upper part of the fuel tank FT becomes the fuel in the fuel tank FT. As the liquid level rises, it escapes to the canister side through the vent hole 33a of the side wall 33, the valve chamber 20S, the connection passage 32b, the communication chamber 21S, and the pipe passage 34a.

  As the fuel level in the fuel tank FT rises, as shown in FIG. 6, the liquid fuel flows into the valve chamber 20S through the communication hole 36b and increases the buoyancy of the first float 42 and the second float 52. . When the fuel level exceeds the first level FL1, the first float 42 rises and closes the connection passage 32b with the seat member 47. Since the pressure in the fuel tank FT increases due to the blockage of the connection passage 32b, the fueling gun detects that the tank internal pressure has increased, or that the fuel in the filler pipe has reached the fueling gun. Auto-stop to stop refueling gun refueling can be activated. The second float 52 of the rollover valve 50 rises to the same height as the first float 42, but the connection hole 45b remains open. Therefore, the inside of the fuel tank FT is connected to the canister side through the vent hole 33a, the valve chamber 20S, the vent hole 44a of the first float 42, the storage chamber 42S, the connection hole 45b, the connection passage 32b, the communication chamber 21S, and the pipe passage 34a. Therefore, the outside of the fuel tank FT is secured.

(3) -2 Operation of the fuel shut-off valve 10 when the vehicle swings When the fuel liquid level is close to the first liquid level FL1 and the vehicle swings, the liquid level in the fuel tank FT shakes. At this time, as shown in FIG. 7, when the fuel level of the fuel tank FT rises to the second liquid level FL2, the second float 52 is further raised by the fuel that has entered the lower part of the valve chamber 20S and the storage chamber 42S, The seat portion 57a of the seat member 57 is seated on the seal portion 45c and closes the connection hole 45b. As described above, the rollover valve 50 closes the connection hole 45b and prevents the fuel from flowing out to the canister when the second liquid level FL2 exceeding the first liquid level FL1 is reached. Therefore, it is possible to prevent the fuel from flowing out during swinging. In such a closed state, as shown in FIG. 4, when the rubber sheet member 57 is seated on the seal portion 45 c, the portion pressed by the seal portion 45 c is bent at the upper part of the second float 52. It is elastically deformed toward the recess 53S. Accordingly, the sheet portion 57a is elastically deformed so as to be pressed and adhered by the small-diameter seal portion 45c. When the restricting portion 46 hits the seat portion 57a, further elastic deformation of the seat portion 57a is restricted.

  On the other hand, when the fuel in the fuel tank FT is consumed or the inclination of the vehicle is eliminated and the fuel level is lowered, the second float 52 is lowered with its buoyancy reduced and opens the connection hole 45b (see FIG. 7 to FIG. 6). Due to the communication of the connection hole 45b, the pressure below the first float 42 in the storage chamber 42S is substantially the same as that in the vicinity of the connection passage 32b, and the force for closing the first float 42 is reduced. That is, by setting the passage area of the connection hole 45b to be smaller than the passage area of the connection passage 32b, the first float 42 is opened with a small force. Such a two-stage valve structure using the first float 42 and the second float 52 functions to promote the improvement of the restart valve characteristic.

(4) Effects of fuel cutoff valve 10 The fuel cutoff valve 10 according to the above embodiment provides the following actions and effects.
(4) -1 As shown in FIG. 4, when the rubber sheet member 57 is seated on the seal portion 45 c, the portion pushed by the seal portion 45 c is a recess for bending above the second float 52. Elastically deforms into 53S. At this time, the bending recess 53S is formed with an inner diameter larger than the outer diameter of the seal portion 45c, and acts as a space for allowing the seal portion 45c to enter and reliably elastically deform the seat portion 57a. Therefore, since the seat portion 57a is elastically deformed so as to be pressed and adhered by the small-diameter seal portion 45c, high sealing performance can be obtained even when vehicle vibrations are applied.

(4) -2 As shown in FIG. 4, even if the second float 52 is inclined and seated on the seal portion 45c, the seat portion 57a is elastically deformed following the seal portion 45c, so that high sealing performance is obtained. Moreover, even when the first float 42 and the second float 52 are relatively inclined, the width of the bending recess 53S is larger than the amount of horizontal displacement due to the inclination. It can be bent into the bending recess 53S.

(4) -3 In the state where the seat portion 57a of the seat member 57 is elastically deformed and seated on the seal portion 45c, the upper surface of the seat portion 57a hits the restricting portion 46 and the rise of the second float 52 is restricted. 57a is not further extended by the seal portion 45c. In other words, the restricting portion 46 is excellent in durability because the restricting portion 46 restricts the amount of elastic deformation of the seat portion 57a so that the seat portion 57a is not subjected to repeated large elastic deformations. It is possible to prevent breakage between the bottom surface of 53S and the seal portion 45c.

(4) -4 As shown in FIGS. 3 and 5, the restricting portions 46 are arranged at equal intervals in the circumferential direction around the seal portion 45 c, so that the contact between the rubber sheet member 57 and the restricting portion 46 is achieved. The area is reduced, and sticking and sticking can be prevented.

(4) -5 As shown in FIG. 3, the seat member 57 is inserted into the second float 52 in a state where the seat member 57 is retained by the retaining portion 57c only by inserting the seat support portion 57b into the valve support hole 53a of the second float 52. Easy to install.

(4) -6 The sheet portion 57a is bent toward the bending recess 53S in which a part of the upper surface of the second float 52 is recessed, and a gap for bending between the upper surface of the second float 52 and the sheet portion 57a is provided. Since there is no need to provide it, the bulkiness of the rollover valve 50 in the height direction can be eliminated, which can contribute to downsizing.

(4) -7 Since the sheet member 57 is assembled to the second float 52 in a stable posture in contact with the upper surface of the second float 52, the surface accuracy of the seal surface of the sheet portion 57a with respect to the seal portion 45c can be increased. Sealability can be improved.

(5) Other Embodiments The present invention is not limited to the above embodiments, and can be carried out in various modes without departing from the gist thereof. For example, the following modifications are possible. is there.

(5) -1 FIG. 8 is a cross-sectional view showing a main part of a fuel cutoff valve 100 according to another embodiment. The present embodiment is characterized in that one sheet member seals with two sheet portions and functions as a flexure and a restriction portion. That is, the fuel cutoff valve 100 includes a full tank regulating valve 140 and a rollover valve 150 in the valve chamber 120 </ b> S in the casing body 130. A connection passage 132b is formed in the ceiling wall portion 132 of the casing body 130, and a seal portion 132c is formed facing the connection passage 132b. A regulating portion 132d is formed on the outer peripheral side of the seal portion 132c.
The full tank regulating valve 140 includes a first float 142, and the rollover valve 150 includes a second float 152 that is housed in a housing chamber 142 </ b> S of the first float 142 so as to be movable up and down. The first float 142 includes a connection hole 145 b formed in the upper wall portion 143. A sheet member 147 is attached to the connection hole 145b. The sheet member 147 includes a disk-shaped sheet portion 147a formed on the upper surface, a disk-shaped sheet portion 147b formed on the lower surface, and a connecting portion 147c that connects the sheet portion 147a and the sheet portion 147b. ing. The upper wall portion 143 includes a bending recess 143Sa formed on the upper surface thereof and a bending recess 143Sb formed on the lower surface thereof. A seal portion 153 a and a restriction portion 153 b are formed on the upper wall portion 153 of the second float 152 of the rollover valve 150.
In the fuel cutoff valve 100 according to the present embodiment, when the first float 142 is raised, the seat portion 147a of the seat member 147 is seated on the seal portion 132c and is bent into the bending recess 143Sa, and the seat portion is formed by the restriction portion 132d. The amount of elastic deformation of 147a is restricted. Further, when the second float 152 is raised, the seal portion 153a is seated on the seat portion 147b of the seat member 147, the seat portion 147b is bent into the bending recess 143Sb, and the elastic deformation amount of the seat portion 147b by the restricting portion 153b. Is regulated.
According to the present embodiment, since one sheet member 147 is bent and sealed at two places by the seal portion 132c and the seal portion 153a, the sealing performance can be improved, and the restriction portion 132d and the restriction portion 153b are provided on the sheet member 147. Since the elastic deformation amount is regulated, the durability can be improved and the number of parts can be reduced.

(5) -2 For the sheet member and the restricting portion provided between the first float and the upper part of the second float, and the bending recess, the sheet member is bent toward the bending recess, and the restricting portion As long as the elastic deformation amount is regulated within a predetermined range, various combinations can be made with the upper part of the first or second float.
(5) -3 In the above embodiment, in addition to the full tank regulating valve, the configuration of the two-stage float, the configuration of the second float, and the rollover valve that prevents the fuel from flowing out when the vehicle rolls over or tilts. However, the present invention is not limited to this and may be applied to a supercharging prevention valve that prevents supercharging by setting the second liquid level to the full tank level.
(5) -4 The fuel shut-off valve according to the above embodiment is used in a so-called in-tank type mounted inside the fuel tank, but is not limited to this, and is welded to the upper surface of the tank upper wall of the fuel tank. In addition, the present invention can be applied to a configuration in which the lower portion is inserted into the mounting hole.

It is sectional drawing which shows the fuel cutoff valve attached to the upper part of the fuel tank of the motor vehicle concerning one Example of this invention. It is sectional drawing which decomposes | disassembles and shows a fuel cutoff valve. It is the perspective view which decomposed | disassembled the rollover valve. It is sectional drawing to which the upper part of the 1st float and the 2nd float was expanded. It is the figure which looked at the lower seal part formed in the lower surface of the upper wall part of a 1st float from the downward direction. It is explanatory drawing explaining operation | movement of the fuel cutoff valve at the time of refueling. It is explanatory drawing explaining operation | movement of the fuel cutoff valve at the time of vehicle rocking | fluctuation. It is sectional drawing which shows the principal part of the fuel cutoff valve concerning another Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Fuel cutoff valve 20 ... Casing 20S ... Valve chamber 20a ... Valve mounting part 21S ... Communication chamber 30 ... Casing main body 30a ... Lower opening 32 ... Ceiling wall part 32a ... Passage formation protrusion 32b ... Connection passage 32c ... Sealing part 33 ... Side wall 33a ... Vent 33b ... Engagement recess 34 ... Tube part 34a ... Pipe passage 35 ... Upper lid 36 ... Bottom plate 36a ... Engagement claw 36b ... Communication hole 36c ... Spring support 40 ... Full tank regulating valve 42 ... No. 1 float 42S ... storage chamber 43 ... upper wall 44 ... side wall 44a ... vent hole 44b ... guide projection 45 ... valve support member 45a ... valve holding recess 45b ... connection hole 45c ... seal part 46 ... regulating part 47 ... seat Member 47a ... Support base 47b ... Seat 48 ... First spring 50 ... Rollover valve 52 ... Second float 52S ... Float chamber 53 ... Upper wall 53 ... Bending recess 53a ... Valve support hole 53Sa ... Drainage groove 54 ... Side wall part 54a ... Guide protrusion 57 ... Sheet member 57a ... Sheet part 57b ... Sheet support part 57c ... Retaining part 58 ... Second spring 100 ... Fuel shut off Valve 120S ... Valve chamber 130 ... Casing body 132 ... Ceiling wall portion 132b ... Connection passage 132c ... Sealing portion 132d ... Restriction portion 140 ... Full tank restriction valve 142 ... First float 142S ... Storage chamber 143 ... Upper wall portion 143Sa ... For bending Recess 143Sb ... Deflection recess 145b ... Connection hole 147 ... Seat member 147a ... Seat part 147b ... Seat part 147c ... Connection part 150 ... Rollover valve 152 ... Second float 153 ... Upper wall part 153a ... Seal part 153b ... Restriction BK ... Bracket FT ... Fuel tank FTa ... Tank upper wall

Claims (5)

A casing (20) that forms a valve chamber (20S) that is attached to the upper part of the fuel tank (FT) and is connected to the outside of the fuel tank, and a float mechanism that is arranged to be movable up and down in the valve chamber (20S). A fuel cutoff valve that cuts off the communication between the fuel tank (FT) and the outside by raising and lowering the float mechanism according to the fuel level in the fuel tank,
The float mechanism is
The storage chamber (42S) opened downward, the connection hole (45b) connecting the storage chamber (42S) and the valve chamber (20S), and the storage chamber provided facing the connection hole (45b) A first float (42) having an annularly projecting seal portion (45c) on the (42S) side;
A second float (52) stored in the storage chamber (42S) so as to be movable up and down;
A sheet member interposed between the first float (42) and the upper part of the second float (52), formed of a flexible material, and having a seat portion (57a) for opening and closing the connection hole (45b). (57)
With
The second float (52) has the sheet portion (57a) pressed by the seal portion (45c) at a position on the upper surface of the second float (52) and facing the seal portion (45c). A bending recess (53S) for sometimes bending,
Elasticity which is formed on the first float (42) or the second float (52) on the outer peripheral side of the seal part (45c), and the sheet part (57a) is elastically deformed into the bending recess (53S). Having a restricting portion (46) for restricting the amount of deformation;
A fuel shut-off valve characterized by The fuel cutoff valve according to claim 1,
The said control part (46) is a fuel cutoff valve arranged in multiple numbers by the circumferential direction so that the outer peripheral part of the said seal part (45c) may be enclosed. The fuel cutoff valve according to claim 1 or 2,
The second float (52) includes a valve support hole (53a) at the shaft center of the second float (52), and the seat member (57) projects from the back side of the seat portion (57a). And a fuel cutoff valve attached to the second float (52) by inserting the seat support (57b) into the valve support hole (53a). The fuel cutoff valve according to any one of claims 1 to 3,
The fuel shut-off valve configured such that the seat portion (57a) is in contact with the upper surface of the second float (52). A casing that is attached to the upper part of the fuel tank and forms a valve chamber (120S) connected to the outside of the fuel tank, and a float mechanism that is arranged to be movable up and down in the valve chamber (120S). In the fuel cutoff valve that cuts off the communication between the fuel tank and the outside by raising and lowering the float mechanism according to the fuel level,
The float mechanism is
A first float (142) having a storage chamber (142S) opened downward, and a connection hole (145b) connecting the storage chamber (142S) and the valve chamber (120S);
A second float (152) having a seal portion (153a) which is accommodated in the storage chamber (142S) so as to be movable up and down, faces the connection hole (145b) and protrudes in an annular shape toward the first float (142); ,
A sheet member (147) having a sheet portion (147b) mounted so as to surround the connection hole (145b) of the first float (142);
With
In the first float (142), the sheet portion (147b) is pressed by the seal portion (153a) at a position opposite to the seal portion (153a) on the lower surface of the first float (142). A bending recess (143Sb) for sometimes bending,
It is formed on the outer peripheral side of the seal portion (153a) and on the upper surface of the second float (152), and regulates the amount of elastic deformation by which the sheet member (147) elastically deforms into the bending recess (143Sb). Having a regulating part (153b),
A fuel shut-off valve characterized by

Images