Switching device

Abstract

To provide a valve device capable of reliably closing an opening part even when a vehicle rolls over.SOLUTION: A valve device 10 includes a housing 15, a float valve 40, and a seal member 80, and an opening part 25 includes a first region 25a, and a second region 25b, the seal member 80 having a first cover part 81, and a second cover part 83, the second cover part 83 having a support portion 85, a wide portion 87, and a narrow portion 89. In the state that the seal member 80 is locked to a float valve 40 and supported by the support part 85, the wide portion 87 covers the front end of the second region 25b. Even in the state that the seal member 80 is shifted from the opening part 25 in the radial direction and / or peripheral direction of the housing 15 to the maximum, the wide portion 87 is set at a width such that it does not protrude from the second region 25b of the opening part 25.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a valve device that is attached to a fuel tank of an automobile or the like and used as a fuel outflow prevention valve, a full tank regulation valve, or the like.

Background Art

[0002] For example, a valve device for preventing fuel in a fuel tank of a vehicle such as an automobile from leaking outside the fuel tank is attached when the vehicle tilts or rolls over. Such a valve device generally has a housing provided with a ventilation chamber above and a valve chamber below through a partition wall having a ventilation hole, and a float valve disposed in the valve chamber so as to be movable up and down. Further, a seal member made of rubber or the like may be disposed above the float valve for the purpose of improving the sealing property with respect to the ventilation hole.

[0003] For example, Patent Document 1 below discloses a housing provided with a valve chamber below and a ventilation chamber above through a partition wall, the partition wall being provided with a ventilation hole communicating therewith, and a float valve accommodated in the valve chamber so as to be movable up and down. A valve seat is formed on the valve chamber side of the partition wall, and an opening is provided inside the valve seat. The opening has a first opening and a second opening extending in a slit shape from at least one location thereof. Above the float valve, a seal portion having elasticity for opening and closing the first opening and the second opening is disposed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Incidentally, when the vehicle rolls over, it is necessary for the float valve to slide and close the opening to prevent fuel from flowing into the ventilation chamber from the opening. However, when the vehicle rolls over, the fuel tank and the valve device itself also roll over accordingly. Then, the float valve will move to one side with respect to the valve chamber of the housing.

[0006] In the case of the valve device of Patent Document 1 above, in the above state, even if the float valve slides in the direction approaching the opening, the seal portion above the float valve may not contact the opening of the housing at a predetermined position and may contact with a displacement, resulting in a situation where the opening cannot be surely closed.

[0007] Therefore, an object of the present invention is to provide a valve device capable of surely closing the opening even when the vehicle rolls over.

Means for Solving the Problems

[0008] In order to achieve the above object, a valve device according to the present invention is provided with a valve chamber communicating downward into a fuel tank and a ventilation chamber communicating upward outside the fuel tank via a partition wall, and an opening for communicating the valve chamber and the ventilation chamber is formed in the partition wall. The valve device includes a housing, a float valve slidably accommodated in the valve chamber, and a seal member disposed above the float valve for closing the opening. The opening has a first region and a second region extending in a slit shape from the first region to form an end of the opening. The seal member has a first cover portion covering the first region and a second cover portion extending from the first cover portion to cover the second region. The second cover portion has a support portion disposed at a tip side in the extending direction for preventing the seal member from coming off the float valve, a wide portion disposed at a base end side in the extending direction relative to the support portion, and a narrow portion provided at a base end side in the extending direction relative to the wide portion and formed narrower than the wide portion. In a state where the seal member is supported by the support portion to prevent it from coming off the float valve, the wide portion covers the tip of the second region, and the width is set such that the second region of the opening does not protrude even when the seal member is displaced maximally in the radial direction and / or circumferential direction with respect to the opening of the housing.

Effect of the Invention

[0009] According to the present invention, the wide portion provided in the second cover portion constituting the seal member is set to a width such that the second region of the opening does not protrude even when the seal member is displaced maximally in the radial direction and / or circumferential direction with respect to the opening of the housing. Therefore, even if the vehicle rolls over and the seal member is displaced with respect to the opening, the first region and the second region of the opening can be firmly covered by the seal member, and the opening can be reliably closed by the seal member.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0011] (An Embodiment of the Valve Device) Hereinafter, with reference to the drawings, an embodiment of the valve device according to the present invention will be described. In the following description, "fuel" means liquid fuel (including fuel droplets), and "fuel vapor" means evaporated fuel.

[0012] As shown in FIGS. 1 and 3, the valve device 10 in this embodiment is provided with a valve chamber V communicating downward into the fuel tank and a ventilation chamber R communicating upward outside the fuel tank via a partition wall 23. An opening 25 communicating the valve chamber V and the ventilation chamber R is formed in the partition wall 23. The valve device 10 includes a housing 15, a float valve 40 slidably accommodated in the valve chamber V, a seal member 80 disposed above the float valve 40 to close the opening 25, and a biasing spring S for biasing the float valve 40.

[0013] Further, the housing 15 of this embodiment has a substantially cylindrical shape and includes a housing main body 20 provided with a partition wall 23 above, a lower cap 30 attached below the housing main body 20, and an upper cover 35 attached above the housing main body 20.

[0014] The housing main body 20 has a peripheral wall 21 having a substantially cylindrical shape, and the partition wall 23 is disposed above it. A plurality of through holes 21a and locking protrusions 21b are formed above the peripheral wall 21, and a locking hole 21c is formed below it. An opening 25 is formed at the central portion of the partition wall 23. Further, a cylindrical wall 27 projects from the upper surface side of the partition wall 23, outside the opening 25. A plurality of ribs 27a project from the upper outer periphery of the cylindrical wall 27. A flange portion 28 projects from the upper outer periphery of the peripheral wall 21. Further, a ring mounting groove 28a is formed between the flange portion 28 and the cylindrical wall 27, and an annular seal ring 29 is mounted in the ring mounting groove 28a (see FIG. 3).

[0015] Further, as shown in FIG. 7, the opening 25 has a first region 25a and a second region 25b that extends from the first region 25a in a slit shape and forms an end portion of the opening 25. The opening 25 in this embodiment has a first region 25a in the shape of a substantially circular hole, and a plurality (here, four) of second regions 25b that extend outward in a slit shape at equal intervals in the circumferential direction from the outer periphery of the first region 25. The central portion forms an opening in a substantially cross shape with an enlarged diameter. Each second region 25b communicates with the first region 25a and is narrower than the maximum inner dimension (here, the inner diameter) of the first region 25a.

[0016] Further, as shown in FIG. 3, the opening 25 has a valve seat 26 that protrudes downward from the peripheral edge on the back side (valve chamber V side). The opening 25 is opened and closed by the seal member 80 coming into contact with and separating from the lower end of the valve seat 26.

[0017] On the other hand, the lower cap 30 has a bottom wall 31 in the shape of a substantially circular plate and a peripheral wall 33 that stands upright from the peripheral edge thereof. A spring support protrusion 31a that supports the lower end of the biasing spring S protrudes from the central portion in the radial direction of the bottom wall 31. A plurality of through holes 31b are formed in the bottom wall 31, and an elastic piece 34 is formed so as to be elastically deformable to suppress the hitting sound when the float valve 40 descends. Further, a plurality of locking claws 33a are formed on the peripheral wall 33.

[0018] Then, by locking each locking claw 33a of the lower cap 30 to each locking hole 21c of the housing body 20, the lower cap 30 is attached below the housing body 20. As a result, a valve chamber V that communicates with a fuel tank (not shown) below the housing is formed via the partition wall 23 (see FIG. 3).

[0019] As shown in FIG. 1, the upper cover 35 has a peripheral wall 36 extending at a predetermined height, a ceiling wall 37 closing the upper part thereof, and a flange portion 36a extending annularly from an intermediate position in the extending direction of the peripheral wall 36. A vent hole (not shown) is formed at a predetermined position of the peripheral wall 36, and a fuel vapor pipe 38 having a substantially cylindrical shape extends outward from the outer peripheral edge portion thereof. A tube (not shown) communicating with a canister or the like disposed outside the fuel tank is connected to the fuel vapor pipe 38. Further, as shown in FIG. 3, a frame-shaped locking piece 39 that locks to the locking projection 21b of the housing body 20 extends vertically from the lower end surface of the peripheral wall 36.

[0020] Then, as shown in FIG. 3, by locking each locking piece 39 of the upper cover 35 and the corresponding locking projection 21b of the housing body 20, the upper cover 35 is mounted above the housing body 20 with the seal ring 29 mounted in the ring mounting groove 28a in contact with the inner periphery of the peripheral wall 36 of the upper cover 35. As a result, a vent chamber R communicating with the outside of the fuel tank is formed above the partition wall 23 (see FIG. 3).

[0021] Next, the float valve 40 will be described in detail.

[0022] The float valve 40 of this embodiment has a float body 50 and a seal support member 60 disposed above the float body 50, which is swingably retained with respect to the float body 50 and retains the seal member 80 in a non-removable manner and supports it so as to be movable a predetermined distance.

[0023] The float body 50 has a peripheral wall 51 extending in the vertical direction with a predetermined length and a ceiling wall 53 disposed above it, and has a substantially cylindrical shape with an open lower part and a closed upper part.

[0024] Also, at two locations facing each other in the circumferential direction of the peripheral wall 51, a pair of guide grooves 51a, 51a extending axially downward from the ceiling wall 53 to the lower part of the peripheral wall are formed. Guide protrusions (not shown) provided on the inner circumference of the housing body 20 are inserted into these guide grooves 51a, 51a to guide the sliding operation of the float valve 40. Further, a plurality of guide ribs 51b extending radially are provided along the axial direction on the outer circumference of the peripheral wall 51. These guide ribs 51b are arranged to face the inner circumference of the peripheral wall 21 of the housing body 20 to guide the sliding operation of the float valve 40.

[0025] Also, a support protrusion 53a having a curved outer surface projects from the center on the surface side (which can also be said to be the "upper surface"; the same applies in the following description) of the ceiling wall 53. The plate-like portion 61 of the seal support member 60 is placed on this support protrusion 53a to support the seal support member 60 so as to be swingable. Further, a plurality (here, four) of protrusions 55 project from the outer peripheral edge portion of the ceiling wall 53 at equal intervals in the circumferential direction.

[0026] Also, at two locations on the outer peripheral surface of the upper end portion of the peripheral wall 51 near the ceiling wall 53 and facing each other in the radial direction, retaining protrusions 57, 57 for retaining the seal support member 60 so as to be swingable with respect to the float body 50 are provided. Each retaining protrusion 57 is slidable along the axial direction Z (see FIG. 4) of the float valve 40 and movable along the width direction Y (see FIG. 4) of the float valve 40 and is inserted into a retaining hole 67a (described later) provided in the seal support member 60.

[0027] Note that the float body 50 is formed with a spring housing recess 59 that is open at the bottom (see FIG. 3), and a biasing spring S is housed in the spring housing recess 59. This float valve 40 is slidably housed and arranged in the valve chamber V between the lower cap 30 with the biasing spring S interposed therebetween. When immersed in fuel, it slides upward by its own buoyancy and the biasing force of the biasing spring S, and when not immersed in fuel, it slides downward by its own weight. Further, this float valve 40 can slide by the biasing force of the biasing spring S even when a vehicle such as an automobile rolls over by 90°, whereby the seal member 80 can be brought into contact with the valve seat 26 to close the opening 25.

[0028] On the other hand, the seal support member 60 of this embodiment is disposed between the float body 50 and the seal member 80 and has a plate-like portion 61 formed with a predetermined thickness. The seal member 80 is placed and supported on the placement surface 61a of the plate-like portion 61 (see FIG. 3).

[0029] Referring also to FIG. 5, the plate-like portion 61 has a central portion 63 and a plurality of extending portions 65 extending outward from the central portion 63. The plate-like portion 61 of this embodiment has a shape that conforms to the plate-like portion 61 so as to be able to receive and support the seal member 80 having a substantially cross shape as a whole. That is, from the central portion 63 of the plate-like portion 61, four extending portions 65 extend radially outward, and the adjacent extending portions 65, 65 in the circumferential direction are orthogonal to each other, forming a substantially cross shape as a whole.

[0030] Further, a pair of extending portions 65, 65 disposed opposite to each other with the central portion 63 interposed therebetween have retaining pieces 67, 67 vertically provided from the back side (the float body 50 side) of their tip portions. Each retaining piece 67 is formed with a retaining hole 67a having an elongated hole shape extending along the axial direction of the float valve 40. This retaining hole 75a is formed to be longer than the axial length of the retaining projection 57 provided on the float body 50 side and wider than the circumferential width of the retaining projection 57, and has a substantially rectangular shape.

[0031] Then, as shown in FIG. 4, each retaining projection 57 is inserted into the retaining hole 67a of each retaining piece 67 from the inside, so that the seal support member 60 is retained in a swingable manner with respect to the float body 50.

[0032] In addition, in a state where the retaining projection 57 is inserted into the retaining hole 67a, a predetermined gap is formed between both sides in the width direction of the retaining hole 67a and both sides in the width direction of the retaining projection 57, and a predetermined gap is also formed between both ends in the axial direction of the retaining hole 67a and both ends in the axial direction of the retaining projection 57.

[0033] Therefore, as shown by the reference signs X, Y, and Z in FIG. 4, the seal support member 60 can move a predetermined distance along the width direction Y orthogonal to the radial direction X of the float valve 40 with respect to the float body 50, and can move a predetermined distance along the axial direction Z of the float valve 40. Further, the seal support member 60 can swing with respect to the float body 50.

[0034] In addition, when the seal support member 60 moves maximally along the axial direction Z with respect to the float body 50, the retaining projection 57 is locked to the inner surfaces at both longitudinal ends of the retaining hole 67a. When the seal support member 60 moves maximally along the width direction Y, the retaining projection 57 is locked to the inner surfaces at both widthwise sides of the retaining hole 67a. Therefore, the seal support member 60 is retained against the float body 50.

[0035] In addition, from the front side (seal member 80 side) of the tip of each extending portion 65, retaining hooks 69 that are inserted into the support holes 85a (see FIG. 6) of the seal member 80 project respectively.

[0036] Each anti-loosening hook 69 has a shaft portion 69a loosely fitted in the support hole 85a and an overhanging portion 69b protruding from the upper end of the shaft portion 69a beyond the inner peripheral edge of the support hole 85a, forming a substantially inverted L shape. Further, the shaft portion 69a is inserted into the support hole 85a of the seal member 80 so as to be movable along the radial direction X of the float valve 40 and also movable along the width direction Y of the float valve 40.

[0037] Also, a plurality of grooves 71 are formed in the mounting surface 61a of the seal support member 60. In this embodiment, a plurality (here, four) of grooves 71 linearly extending from the outer peripheral edge portion between the base end portions of the adjacent extending portions 65, 65 toward the center of the central portion 63 are formed, and each groove 71 communicates with each other through a circular recess 71a provided at the center of the central portion 63.

[0038] Next, the seal member 80 will be described with reference to FIGS. 1, 4, 6, etc.

[0039] This seal member 80 is disposed above the seal support member 60, is anti-loosening supported so as to be movable a predetermined distance with respect to the seal support member 60, and comes into contact with and separates from the valve seat 26 provided in the opening 25 to open and close the opening 25.

[0040] As shown in FIG. 6, this seal member 80 has a first cover portion 81 covering the first region 25a of the opening 25 and a second cover portion 83 extending from the first cover portion 81 so as to cover the second region 25b of the opening 25. That is, this seal member 80 has a first cover portion 81 and a plurality of second cover portions 83 extending outward from the outer periphery of the first cover portion 81. More specifically, the seal member 80 in this embodiment has four second cover portions 83 extending radially outward from the outer periphery of the first cover portion 81 (extending in four directions) corresponding to the opening 25 having a substantially cross-shaped opening, and the adjacent second cover portions 83, 83 in the circumferential direction are orthogonal to each other, forming a substantially cross shape as a whole.

[0041] In addition, each second cover part 83 is arranged on the tip side in its extending direction, and has a support part 85 that retains and supports the seal member 80 with respect to the float valve 40, and a wide part 87 that is arranged on the base end side in the extending direction of the second cover part 83 rather than this support part 85 (it can also be said that it is arranged at the part where the tip of the second region 25b of the opening 25 is located), and a narrow part 89 that is provided on the base end side in the extending direction of the second cover part 83 rather than this wide part 87 (it can also be said that it is provided at a position closer to the first region 25a of the opening 25 with respect to the wide part 87) and is formed to be narrower than the wide part 87. In the following description of each component of the second cover part 83, "tip" and "tip part" mean the tip and tip part in the extending direction of the second cover part 83, and "base end" and "base end part" mean the base end and base end part in the extending direction of the second cover part 83.

[0042] Hereinafter, each part of the second cover part 83 will be described more specifically.

[0043] As shown in FIG. 6(b), the tip part in the extending direction (which can also be said to be the extending direction) of each second cover part 83 forms the above support part 85. This support part 85 extends with a constant width W1, and the tip corner part in its extending direction is in an R shape. Also, the width W1 of the support part 85 is smaller than the width W2 of the wide part 87 and the width W3 of the narrow part 89. Further, a support hole 85a having a substantially long hole shape that extends long along the extending direction of the second cover part 83 is formed in this support part 85. Both longitudinal ends of each support hole 85a have a rounded shape, and the shaft part 69a of the retaining hook 69 provided on the seal support member 60 is inserted so as to be loosely fitted. Note that the base end part in the extending direction (the end part on the side of the first cover part 81) of the support hole 85a slightly overlaps the region where the wide part 87 is provided.

[0044] Then, as shown in FIG. 4, by inserting the shaft part 69a of each retaining hook 69 into each support hole 85a and positioning the overhanging part 69b at the outer peripheral edge of each support hole 85a respectively, the seal member 80 is retained and supported so as to be movable by a predetermined distance with respect to the seal support member 60.

[0045] Also, when the shaft portion 69a is inserted into the support hole 85a, a predetermined gap is formed between both axial ends of the support hole 85a and the shaft portion 69a, and a predetermined gap is also formed between both widthwise sides of the support hole 85a and the shaft portion 69a.

[0046] Therefore, as shown by the reference signs X, Y, Z in FIG. 4, the seal member 80 is movable relative to the seal support member 60 by a predetermined distance along the radial direction X of the float valve 40, and is movable by a predetermined distance along the widthwise direction Y of the float valve 40, and is further movable by a predetermined distance along the axial direction Z of the float valve 40.

[0047] Also, when the seal member 80 moves maximally relative to the seal support member 60: (1) in the radial direction X, the shaft portion 69a engages with the inner surfaces at both axial ends of the support hole 85a; (2) in the widthwise direction Y, the shaft portion 69a engages with the inner surfaces on both widthwise sides of the support hole 85a; (3) in the axial direction Z, the protruding portion 69b engages with the front peripheral edge of the support hole 85a. Thus, the seal member 80 is supported against coming off relative to the seal support member 60.

[0048] On the other hand, as shown in FIG. 6, the wide portion 87 is continuously provided at a position closer to the base end of the second cover portion 83 than the support portion 85. The wide portion 87 has top portions 87a, 87a that are the widest in the second cover portion 83, first tapered portions 87b, 87b that gradually become narrower from the top portions 87a, 87a toward the tip in the extending direction of the second cover portion 83, and second tapered portions 87c, 87c that gradually become narrower from the top portions 87a, 87a toward the base end in the extending direction of the second cover portion 83, and has a shape protruding by a predetermined width from both side edges in the widthwise direction of the second cover portion 83.

[0049] Also, as shown in FIG. 7, a wide portion 87 is provided so as to be positioned at the tip of the second region 25b of the opening 25 in a state where the vehicle is not overturned. In this embodiment, the wide portion 87 is provided such that the tip of the second region 25b of the opening 25 is positioned between the tops 87a, 87a of the wide portion 87. Further, the first tapered portion 87b is longer than the second tapered portion 87c in the extending direction of the second cover portion 83.

[0050] Also, when the width of the wide portion 87, that is, the length between the tops 87a, 87a of the wide portion 87 is “W2”, the width W2 of the wide portion 87 is formed to be larger than the width W1 of the support portion 85 and the width W3 of the narrow portion 89.

[0051] Furthermore, in a state where the seal member 80 is supported by the support portion 85 so as not to come off with respect to the float valve 40, the wide portion 87 covers the tip of the second region 25b in the extending direction of the opening 25, and even in a state where the seal member 80 is maximally displaced in the radial direction and / or the circumferential direction with respect to the opening 25, the width is set so that the second region 25b of the opening 25 does not protrude.

[0052] FIG. 10 shows a state where the vehicle is overturned by 90°, the valve axis direction of the float valve 40 (the direction along the axis of the float valve 40) is horizontal, and the seal member 80 is maximally displaced in the radial direction and / or the circumferential direction with respect to the opening 25. Even in this state, the wide portion 87 covers the tip of the second region 25b of the opening 25, and the width W2 is set so that the second region 25b of the opening 25 does not protrude. In this state, among the plurality of second regions 25b constituting the opening 25, the tips of some of the second regions 25b are positioned at the wide portion 87, and the tips of the other second regions 25b are positioned at the narrow portion 89 instead of the wide portion 87 (see FIG. 10).

[0053] Further, the narrow portion 89 is provided via notches 91, 91 formed on both sides of the base end portion of the second cover portion 83. More specifically, notches 91 are formed toward the center C of the first cover portion 81 between the base end portions of the second cover portions 83, 83 that extend from the outer periphery of the first cover portion 81 and are adjacent to each other in the circumferential direction, and the narrow portion 89 is provided via the notches 91.

[0054] In the case of this embodiment, between the base end portions of the second cover portions 83, 83 that are adjacent to each other in the circumferential direction (the boundary portion of the portion where the base end portions of the adjacent second cover portions 83, 83 are connected to each other) among the second cover portions 83 that extend from the outer periphery of the first cover portion 81 in four directions, notches 91 having a constant width and rounded tips are formed by notching obliquely inward toward the center C of the first cover portion 81. Then, via a pair of notches 91, 91 formed adjacent to each other in the circumferential direction of the first cover portion 81, at the base end portion in the extending direction of each second cover portion 83, a narrow portion 89 is formed with a width W3 that is smaller than the width W2 of the wide portion 87 and larger than the width W1 of the support portion 85.

[0055] Further, the narrow portion 89 is on the base end portion side of the second cover portion 83 and is disposed at the boundary portion with the first cover portion 81, having a constricted shape. That is, the narrow portion 89 is on the base end portion side in the extending direction of the second cover portion 83 rather than the wide portion 87 and is disposed at the boundary portion with the first cover portion 81. As a result of a pair of notches 91, 91 being formed by notching from the boundary portion of the portion where the base end portions of the adjacent second cover portions 83, 83 are connected to each other, the narrow portion 89 has a constricted shape in the width direction of the second cover portion 83.

[0056] Also, as shown in FIG. 7, when the float valve 40 and the seal member 80 are viewed from the valve axis direction, the groove 71 of the seal support member 60 is visible from the notch 91 of the seal member 80.

[0057] Note that the sealing member 80 described above is integrally formed of all constituent parts such as the first cover part, the second cover part, the support part, the wide part, and the narrow part by an elastic material such as rubber or elastic elastomer, for example.

[0058] (Modification example) The shapes and structures of the housing constituting the present invention, the housing body constituting the housing body, the lower cap, the upper cover, the sealing member, the first and second regions of the opening, the first and second cover parts constituting the sealing member, the support part constituting the second cover part, the wide part, the narrow part, etc. are not limited to the above aspects.

[0059] In addition, the housing 15 in the above embodiment is composed of a housing body 20, a lower cap 30, and an upper cover 35. However, the housing may have at least a partition wall and an opening structure.

[0060] Furthermore, the opening 25 in this embodiment is a substantially cross-shaped opening with a diameter-expanded central portion. However, the opening may have a first region and a second region that extends in a slit shape from the first region to form an end portion of the opening.

[0061] For example, as shown in FIG. 12(a), an opening 25B having a first region 25a having a substantially circular hole shape in the central portion and a pair of second regions 25b, 25b extending in a slit shape from two diametrically opposed locations on the outer periphery of the first region 25a may be used (the slit-shaped second regions 25b extend from the first region 25a in two directions). Note that the pair of second regions 25b, 25b extend on the same straight line.

[0062] Also, as shown in FIG. 12(b), the opening 25C may be a slit-shaped opening extending linearly as a whole. In this case, the central portion in the extending direction of the opening 25C forms the first region 25a, and both side portions in the extending direction extending from both sides thereof form a pair of second regions 25b, 25b. Note that the first region 25a and the second region 25b have the same width.

[0063] Furthermore, as the opening, it may be configured to include a first region and a second region that extends in a slit shape from the first region in one direction, three directions, or five or more directions and has a width narrower than or the same as that of the first region.

[0064] Also, the peripheral wall 21 of the housing body 20, the peripheral wall 33 of the lower cap 30, and the peripheral wall 36 of the upper cover 35 in this embodiment are substantially cylindrical, but these peripheral walls may be, for example, elliptical cylindrical or rectangular cylindrical.

[0065] Furthermore, in this embodiment, one float valve 40 is accommodated and arranged in one valve chamber V formed in the housing 15. However, for example, a plurality of float valves may be accommodated and arranged in one valve chamber (functioning as a full-tank regulating valve, a fuel cut valve, a pressure regulating valve, etc.), or a plurality of valve chambers may be defined in the housing and float valves may be accommodated and arranged in each valve chamber.

[0066] Also, the seal member 80 of this embodiment has the shape shown in FIGS. 6 and 7, but may have the shape shown in FIGS. 11 and 12, for example.

[0067] The seal member 80A shown in FIG. 11, similar to the seal member 80 shown in FIG. 6, has four second cover portions 83 and is generally in a substantially cross shape. However, the support portion 85 provided at the distal end side in the extending direction of the second cover portion 83 and the wide portion 87 provided closer to the base end portion than that are formed with the same width. Note that the wide portion 87 is provided such that its base end portion is located at the tip of the second region 25b of the opening 25.

[0068] Further, the seal member 80B shown in Fig. 12(a) corresponds to the above-described opening 25B, and a pair of second cover portions 83, 83 extending on the same straight line extend from two locations on the outer periphery of the first cover portion 81 that face each other in the radial direction, and as a whole, it has a substantially long plate shape (the second cover portions 83 extend from the first cover portion 81 in two directions). In the case of this seal member 80B, a wide portion 87 is provided such that the tip of the second region 25b of the opening 25 is located between the tops 87a, 87a of the wide portion 87. Further, a pair of notches 91, 91 forming narrow portions 89 are formed on both sides in the width direction orthogonal to the extending direction of the seal member 80B extending in a substantially long plate shape, and two sets are formed at a predetermined interval with respect to the extending direction of the seal member 80B.

[0069] Furthermore, the seal member 80C shown in Fig. 12(b) corresponds to the above-described opening 25C and has a shape extending in a substantially long plate shape as a whole. Also, a pair of notches 91, 91 having a substantially triangular groove shape are formed on both sides in the width direction at the central portion in the extending direction of the seal member 80B, and a narrow portion 89 is provided at the center in the extending direction of the seal member 80B via these notches 91, 91, and this narrow portion 89 also serves as the first cover portion 81. Further, the tops 87a, 87a of the wide portion 87 extend longer than the wide portion 87 in the seal member 80 shown in Figs. 6 and 7, the seal member 80A shown in Fig. 11, and the seal member 80B shown in Fig. 12(a).

[0070] Also, as the seal member, it may be configured to include a first cover portion and a second cover portion extending from the first cover portion in one direction, three directions, or five or more directions.

[0071] Furthermore, the wide portion 87 of this embodiment includes top portions 87a, 87a, first tapered portions 87b, 87b, and second tapered portions 87c, 87c that are shorter than the first tapered portions 87b, 87b. However, for example, as the wide portion, it may be a shape that protrudes from both side edges in the width direction of the second cover portion so as to form a curved surface, an arc shape, a substantially triangular shape, or a substantially trapezoidal shape. Also, as the wide portion, the second tapered portion may be longer than the first tapered portion, or the first tapered portion and the second tapered portion may extend with the same length.

[0072] Also, the narrow portion 89 of this embodiment is provided via the notch 91. However, the narrow portion does not necessarily have to be provided via the notch, and it may be arranged closer to the first region than the wide portion and may simply be narrower than the wide portion.

[0073] (Function and Effect) Next, the function and effect of the valve device 10 having the above structure will be described.

[0074] As shown in FIG. 3, when the fuel level in the fuel tank does not rise and the float valve 40 is not immersed in the fuel, the float valve 40 descends in the valve chamber V, the seal member 80 separates from the valve seat 26, the opening 25 is open, and the valve chamber V and the ventilation chamber R communicate with each other through the opening 25. In this state, when the fuel vapor in the fuel tank increases and the tank internal pressure rises due to driving of the vehicle or the like, the fuel vapor flows into the valve chamber V from the through-hole 31b of the lower cap 30 and the through-hole 21a of the housing body 20, passes through the opening 25, flows into the ventilation chamber R, and is sent to a canister (not shown) via the fuel vapor pipe 38, thereby suppressing the pressure rise in the fuel tank.

[0075] When the vehicle turns a curve, travels on a rough or sloped road, or topples over due to an accident, the fuel in the fuel tank sloshes violently, causing the fuel level to rise and the float valve 40 to be immersed in the fuel. In this state, the float valve 40 rises due to the buoyancy of the float valve 40 itself and the biasing force of the biasing spring S. As a result, as shown in FIG. 8, the first cover portion 81 and the second cover portion 83 of the seal member 80 abut against the valve seat 26, closing the first region 25a and the second region 25b of the opening 25, thereby preventing fuel from flowing into the ventilation chamber R through the opening 25.

[0076] Incidentally, FIG. 8 above shows the case where the float valve 40 rises straight without tilting with respect to the axial direction of the housing 15. However, the float valve 40 may tilt and rise with respect to the axial direction of the housing 15. In this case, since the seal support member 60 is swingable with respect to the float body 50, when the float valve 40 tilts and rises and the seal member 80 abuts against the valve seat 26 in a tilted state, the seal support member 60 swings appropriately with respect to the float body 50, correcting the tilt of the seal member 80. Therefore, the seal member 80 can abut against the valve seat 26 without tilting and firmly close the opening 25.

[0077] In the above state, when the sloshing of the fuel subsides and the buoyancy from the fuel no longer acts on the float valve 40, or when the pressure in the fuel tank decreases, the float valve 40 descends due to its own weight. Then, as shown in FIG. 9, the seal support member 60 descends by a predetermined distance with respect to the seal member 80 that abuts and adheres to the valve seat 26, and the retaining projection 57 of the float body 50 engages with the inner surface of the lower end of the retaining hole 67a of the seal support member 60.

[0078] As a result, the load of the float body 50 acts on the seal support member 60, causing the shaft portion 69a of the retaining hook 69 of the seal support member 60 to descend within the support hole 85a of the seal member 80, and the overhanging portion 69b of the retaining hook 69 to engage with the outer peripheral edge of the support hole 85a on the front side. Thereby, the load of the float body 50 and the seal support member 60 acts on the second cover portion 83 of the seal member 80 via the seal support member 60.

[0079] Then, the second cover portion 83 of the seal member 80 is elastically deformed so as to be pulled obliquely downward, and the second cover portion 83 moves along the axial direction Z and the radial direction X of the float valve 40. As a result, as shown in FIG. 9, the second cover portion 83 gradually moves away from the base end portion of the wide portion 87 and the narrow portion 89 side with respect to the valve seat 26, opens the second region 25b of the opening 25, and then the first cover portion 81 is peeled off from the valve seat 26. Therefore, the first region 25a of the opening 25 is opened, and the entire opening 25 can be completely opened. As a result, the reopening valve pressure of the float valve 40 can be improved. Note that "improving the reopening valve pressure" means the performance of being able to easily peel the float valve from the valve seat provided in the opening and open the opening even when the internal pressure of the tank is high. Note that as the seal member 80 is peeled off from the valve seat 26, the entire float valve 40 descends.

[0080] By the way, a vehicle such as an automobile may roll over 90° due to an accident or the like. In this case, as the vehicle rolls over, the fuel tank and the valve device also roll over and become horizontal (the valve axis direction of the float valve 40 becomes horizontal or nearly horizontal). As shown in FIG. 10, the seal member 80 is displaced in the circumferential direction and the radial direction of the housing 15 with respect to the opening 25.

[0081] However, even in such a situation, the valve device 10 can surely close the opening 25.

[0082] That is, in this valve device 10, with the seal member 80 being supported by the support portion 85 in a non-removable manner with respect to the float valve 40, the wide portion 87 covers the tip of the second region 25b of the opening 25 in the extending direction as shown in FIG. 10, and even when the seal member 80 is displaced maximally in the radial direction and / or circumferential direction of the housing 15 with respect to the opening 25, the second region 25b of the opening 25 is set to a width that does not protrude.

[0083] Therefore, even if the vehicle rolls over as described above and the seal member 80 is displaced in the radial direction or circumferential direction of the housing 15 with respect to the opening 25, the first region 25a and the second region 25b of the opening 25 can be firmly covered by the seal member 80. Thus, while enhancing the sealing performance of the seal member 80 with respect to the valve seat 26, the opening 25 can be reliably closed by the seal member 80. As a result, fuel inflow into the ventilation chamber R during vehicle rollover can be prevented.

[0084] Also, the narrow portion 89 provided in the second cover portion 83 can make the seal member 80 easily bend and deform, so that the seal member 80 in contact with the valve seat 26 of the opening 25 can be easily peeled off from the opening 25. That is, in the state shown in FIG. 9, when the second cover portion 83 is pulled, it becomes easy to bend and deform, and the base end portion of the wide portion 87 of the second cover portion 83, the narrow portion 89, and further the first cover portion 81 can be easily peeled off from the valve seat 26. As a result, the reopening valve pressure of the float valve 40 can be improved.

[0085] Furthermore, in this embodiment, as shown in FIG. 7, the first region 25a of the opening 25 is formed larger than the second region 25b of the opening 25, and the narrow portion 89 of the second cover portion 83 of the seal member 80 is provided via notches 91, 91 formed on both sides of the base end portion of the second cover portion 83.

[0086] According to the above aspect, since the narrow portion 89 has the above shape, while ensuring the sealing performance of the seal member 80 with respect to the opening 25, the seal member 80 can be easily formed into a shape that is easily bendable and deformable.

[0087] Also, in this embodiment, as shown in FIGS. 6 and 7, the support portion 85 of the seal member 80 is formed to be narrower than the wide portion 87.

[0088] According to this aspect, the support portion 85 of the seal member 80 can be easily bent and deformed, and the area of the support portion 85 is reduced, making it difficult for gases such as air and fuel vapor to hit. As a result, it is possible to prevent the seal member 80, and thus the entire float valve 40, from being lifted up.

[0089] Furthermore, in this embodiment, the second cover portion 83 of the seal member 80 extends from the outer periphery of the first cover portion 81 in at least three directions (here, four directions), and the notch 91 is formed toward the center C of the first cover portion 81.

[0090] According to the above aspect, since the second cover portion 83 extends from the outer periphery of the first cover portion 81 in at least three directions and the notch 91 is formed toward the center C of the first cover portion 81, it is possible to easily and evenly bend and deform the second cover portion 83.

[0091] Also, the present invention is not limited to the above-described embodiment, and various modified embodiments are possible within the scope of the gist of the present invention, and such embodiments are also included in the scope of the present invention.

Explanation of Reference Numerals

[0092] 10 Valve device 15 Housing 20 Housing body 23 Partition wall 25, 25B, 25C Opening 25a First region 25b Second region 26 Valve seat 30 Lower cap 35 Upper cover 40 Float valve 50 Float body 60 Seal support member 80, 80A, 80B, 80C seal member 81 First cover part 83 Second cover part 85 Support part 87 Wide part 89 Narrow part 91 Notch S Biasing spring R Ventilation chamber V Valve chamber

Claims

1. A housing provided with a valve chamber communicating downward into a fuel tank and a ventilation chamber communicating upward outside the fuel tank via a partition wall, and an opening formed in the partition wall to communicate the valve chamber and the ventilation chamber; A float valve slidably accommodated in the valve chamber; And a seal member disposed above the float valve to close the opening. The opening has a first region and a second region extending in a slit shape from the first region to form an end of the opening. The seal member has a first cover portion covering the first region and a second cover portion extending from the first cover portion to cover the second region. The second cover portion Has a support portion disposed on the tip side in the extending direction to prevent the seal member from coming off with respect to the float valve, A wide portion disposed on the base end side in the extending direction rather than the support portion, And a narrow portion provided on the base end side in the extending direction rather than the wide portion and formed to be narrower than the wide portion. In a state where the seal member is prevented from coming off with respect to the float valve by the support portion, the wide portion covers the tip of the second region, and even in a state where the seal member is maximally displaced in the radial direction and / or circumferential direction with respect to the opening, the second region of the opening is set to a width that does not protrude. A valve device characterized by this.

2. The first region is formed larger than the second region. The valve device according to claim 1, wherein the narrow portion is provided through notches formed on both sides of the base end portion of the second cover portion.

3. The valve device according to claim 1 or 2, wherein the support portion is formed narrower than the wide portion.

4. The valve device according to claim 2, wherein the second cover portion extends from the outer periphery of the first cover portion in at least three directions, and the notch is formed toward the center of the first cover portion.

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