Valve device

Abstract

[Problem] To provide a valve device capable of improving workability in an assembly process. [Solution] The valve device comprises: a housing having a valve chamber 31 and a ventilation chamber 33; a float valve 7 housed to be liftable inside the valve chamber 31; and a pressure adjustment valve 6 housed to be liftable inside the ventilation chamber 33. The housing has: a housing body 5 having a partition wall 52, in which a valve hole 522 is formed, and a housing wall 54 surrounding and housing the pressure adjustment valve 6; and a cover 4 mounted on an upper part of the housing body 5. The float valve 7 opens and closes the valve hole 522 by being lifted up and down, and the pressure adjustment valve 6 opens and closes the valve hole 522 by being lifted up and down. The cover 4 has: a ceiling wall 42 covering an area upper from the partition wall 52; and a protruding wall 45 protruding from the ceiling wall 42 toward the partition wall 52 and disposed around the housing wall 54. In an axial direction in which the pressure adjustment valve 6 being lifted up and down, a lower end 451 of the protruding wall 45 exists at a lower position from an upper end 545 of the housing wall 54.

Description

Valve device

[0001] The present invention relates to a valve device for adjusting the pressure inside a fuel tank mounted on a vehicle such as an automobile.

[0002] Fuel tanks installed in vehicles such as automobiles are equipped with a valve device. When the internal pressure of the fuel tank rises above a predetermined value, the valve device allows fuel vapor inside the fuel tank to escape to the outside of the fuel tank, preventing the fuel tank from bursting. In addition, when the internal pressure of the fuel tank falls below a predetermined value below the ambient air pressure, the valve device allows outside air to flow into the fuel tank from the outside, preventing the fuel tank from collapsing.

[0003] As such a valve device, Patent Document 1 discloses a valve device including a housing, a float valve, and a pressure regulating valve. The housing has a valve chamber communicating with the inside of the fuel tank via a partition wall having a valve hole, and a vent chamber communicating with the outside of the fuel tank. The pressure regulating valve is formed in a disk shape of a predetermined thickness and is housed in a housing provided in the vent chamber so that it can be raised and lowered.

[0004] The housing has a housing main body and a cover. The cover is attached to the top of the housing main body by engaging a locking piece provided on the cover with a locking protrusion provided on the housing main body, and defines a ventilation chamber together with the partition wall of the housing main body. The cover also has a position restricting portion. The position restricting portion is formed in the shape of a protrusion of a predetermined length from the inner surface of the top wall of the cover, and the lower end of the position restricting portion abuts against the surface of the pressure regulating valve, thereby determining the maximum raised position (full stroke position) of the pressure regulating valve.

[0005] Here, when attaching the cover to the housing body, depending on the position of the valve device, the pressure regulating valve may fall out of the accommodation portion of the housing body. That is, after the cover is attached to the housing body, the position restricting portion of the cover restricts the maximum raised position of the pressure regulating valve, preventing the pressure regulating valve from falling out of the accommodation portion of the housing body. On the other hand, when the cover is attached to the housing body, the position restricting portion of the cover cannot restrict the maximum raised position of the pressure regulating valve, and depending on the position of the valve device, the pressure regulating valve may fall out of the accommodation portion of the housing body. Therefore, it is desirable to prevent the pressure regulating valve from falling out regardless of the position of the valve device and improve the workability of the assembly process.

[0006] International Publication No. 2021 / 132035

[0007] The present invention has been made in view of the above circumstances, and has an object to provide a valve device that can improve the workability of the assembly process.

[0008] One aspect of the present invention is a fuel tank ... and a cover attached to a portion of the partition wall and defining the vent chamber together with the partition wall, wherein the float valve opens and closes the valve hole by rising and falling, and the pressure regulating valve opens and closes the valve hole by rising and falling, the cover has a ceiling wall covering the upper part of the partition wall, and a protruding wall protruding from the ceiling wall toward the partition wall and arranged around the storage wall, wherein in the axial direction in which the pressure regulating valve rises and falls, the lower end of the protruding wall is located at a position lower than the upper end of the storage wall.

[0009] According to one aspect of the present invention, a cover attached to the top of a housing body and defining a ventilation chamber together with the partition wall of the housing body has a ceiling wall and a protruding wall. The ceiling wall covers the upper part of the partition wall of the housing body. The protruding wall protrudes from the ceiling wall toward the partition wall of the housing body and is disposed around an accommodation wall that surrounds and accommodates the pressure regulating valve. In the axial direction in which the pressure regulating valve rises and falls, the lower end of the protruding wall is located below the upper end of the accommodation wall. Therefore, regardless of the position of the valve device, the protruding wall can prevent the pressure regulating valve from climbing over the accommodation wall and falling out of the inside of the accommodation wall (i.e., the accommodation portion). As a result, the valve device according to the present invention can improve the workability of the assembly process.

[0010] According to the present invention, it is possible to provide a valve device that can improve the workability of the assembly process.

[0011] 10 is a plan view illustrating the valve device according to the present embodiment; FIG. 11 is an exploded view illustrating the valve device according to the present embodiment; FIG. 12 is a cross-sectional view taken along the line A-A in FIG. 2; FIG. 13 is a cross-sectional view taken along the line C-C in FIG. 1; FIG. 14 is an enlarged cross-sectional view taken along the line A-A in FIG. 2; FIG. 15 is an enlarged cross-sectional view taken along the line B-B in FIG. 1; FIG. 16 is a perspective view illustrating a housing main body according to the present embodiment; FIG. 17 is an enlarged perspective view illustrating the vicinity of the accommodating wall according to the present embodiment; FIG. 18 is a perspective view of the cover according to the present embodiment viewed from diagonally below; FIG. 19 is a plan view illustrating the cover according to the present embodiment in a second state; FIG. 19 is a cross-sectional view taken along the line D-D in FIG. 20; FIG. 21 is an enlarged cross-sectional view illustrating the cover according to the present embodiment in a second state; FIG. 22 is an enlarged cross-sectional view illustrating the valve device when the cover according to the present embodiment is in the second state and the up-down direction is reversed; FIG. 23 is an enlarged cross-sectional view illustrating a first modified example when the cover according to the present embodiment is in the second state; FIG. 24 is an enlarged cross-sectional view illustrating a second modified example when the cover according to the present embodiment is in the second state.

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the embodiments described below are preferred specific examples of the present invention, and therefore various technically preferable limitations are applied, but the scope of the present invention is not limited to these aspects unless otherwise specified in the following description to the effect that the present invention is limited. Furthermore, in each drawing, similar components are given the same reference numerals, and detailed descriptions thereof will be omitted as appropriate.

[0013] FIG. 1 is a plan view showing the valve device according to this embodiment. FIG. 2 is an exploded view showing the valve device according to this embodiment. FIG. 3 is a cross-sectional view taken along the line A-A in FIG. 2. FIG. 4 is a cross-sectional view taken along the line C-C in FIG. 1. FIG. 3 shows the valve device according to this embodiment in an assembled state. FIG. 4 is an enlarged cross-sectional view showing the vicinity of the locking claw 512 of the housing main body 5 and the locking piece 47 of the cover 4.

[0014] The valve device 2 according to this embodiment is attached to a fuel tank 10 (see FIG. 3) mounted on a vehicle such as an automobile, and adjusts the pressure inside 101 of the fuel tank 10. As shown in FIG. 2, the valve device 2 includes a housing 3, a pressure adjustment valve 6, a first float valve 7, and a second float valve 8. The housing 3 includes a cover 4, a housing main body 5, and a cap 9.

[0015] The first float valve 7 is also called a roll over valve (ROV) or the like, and prevents fuel from leaking to the outside 102 of the fuel tank 10, for example, when the vehicle brakes, turns, parks on an incline, or rolls over. The second float valve 8 is also called a fill limit vent valve (FLVV) or the like, and regulates the state in which the fuel tank 10 is filled with fuel (i.e., full), and has the same function as the first float valve 7. Herein, "fuel" means liquid fuel (including fuel droplets). Also, in this specification, "fuel vapor" means evaporated fuel gas.

[0016] 2 and 3, the valve device 2 has a structure in which a first float valve 7 and a second float valve 8 are housed integrally in a housing 3. However, the valve device 2 does not necessarily have to include the second float valve 8, and may include only the first float valve 7. The first float valve 7 of this embodiment is an example of the "float valve" of the present invention. In the following description, an example will be given in which the valve device 2 includes the first float valve 7 and the second float valve 8.

[0017] As shown in FIG. 3 , the housing 3 has therein a first valve chamber 31, a second valve chamber 32, and a vent chamber 33. The first valve chamber 31 is in communication with the interior of the fuel tank 10 through a vent hole (not shown) formed in the cap 9, and houses the first float valve 7. That is, the first float valve 7 is housed inside the first valve chamber 31. The second valve chamber 32 is in communication with the interior of the fuel tank 10 through a vent hole (not shown) formed in the cap 9, and houses the second float valve 8. That is, the second float valve 8 is housed inside the second valve chamber 32. The vent chamber 33 is in communication with the outside 102 of the fuel tank 10 through a fuel vapor pipe 44 of the cover 4, and houses the pressure regulating valve 6. That is, the pressure regulating valve 6 is housed inside the vent chamber 33.

[0018] The housing main body 5 has a peripheral wall 51, a partition wall 52, a flange portion 53, and a storage wall 54. The peripheral wall 51 has a generally cylindrical shape and has a locking claw 511 and a locking claw 512. The locking claw 511 protrudes outward from the outer surface of the lower portion of the peripheral wall 51 and is engaged with a locking hole 911 formed in the peripheral wall 91 of the cap 9. The locking claw 511 is engaged with the locking hole 911, thereby attaching the cap 9 to the lower portion of the housing main body 5. As a result, the first valve chamber 31 and the second valve chamber 32 are formed below the partition wall 52. In this specification, "downward" refers to the downward direction of a vertical line (i.e., a line perpendicular to a horizontal plane). Note that the peripheral wall 51 of the housing main body 5 may have a locking hole instead of the locking claw 511, and the cap 9 may have a locking claw instead of the locking hole 911.

[0019] The locking claws 512 protrude outward from the outer surface of the upper portion of the peripheral wall 51 and are engaged with locking holes 471 formed in the locking pieces 47 of the cover 4. By engaging the locking claws 512 with the locking holes 471, the cover 4 is attached to the upper portion of the housing main body 5. As a result, the ventilation chamber 33 is formed above the partition wall 52. In this specification, "upward" refers to an upward direction along a vertical line (i.e., a line perpendicular to a horizontal plane). The locking claws 512 of the housing main body 5 of this embodiment are an example of a "first engagement portion" of the present invention. The locking pieces 47 of the cover 4 of this embodiment are an example of a "second engagement portion" of the present invention. It is noted that the peripheral wall 51 of the housing main body 5 may have locking holes instead of the locking claws 512, and the locking pieces 47 of the cover 4 may have locking claws instead of the locking holes 471.

[0020] 4, when the locking claws 512 are locked in the locking holes 471 (i.e., when the locking claws 512 engage with the locking pieces 47), the cover 4 enters a first state in which it is permanently fixed to the housing main body 5. FIGS. 1 and 3 show the first state in which the cover 4 is permanently fixed to the housing main body 5. On the other hand, when the locking pieces 47 come into contact with the locking claws 512 before the cover 4 transitions to the first state, the cover 4 enters a second state in which it is held and temporarily fixed to the housing main body 5 (see FIGS. 10 and 11). Details of the second state in which the cover 4 is held and temporarily fixed to the housing main body 5 will be described later.

[0021] The partition wall 52 is provided on the upper part of the peripheral wall 51 and has a generally circular plate shape. The partition wall 52 may be provided midway along the axial direction of the peripheral wall 51. The shape of the partition wall 52 is not limited to a simple circular plate, but may have a cylindrically raised central portion and a stepped wall portion (shoulder-shaped wall portion) on the periphery of the central portion. The position and shape of the partition wall 52 are not particularly limited.

[0022] As shown in FIG. 3 , the partition wall 52 has a first valve hole 522 and a second valve hole 524. The first valve hole 522 is formed as a circular through-hole and connects the first valve chamber 31 and the vent chamber 33. A first valve seat 525 and a third valve seat 523 (see FIGS. 5 and 8 ) are provided on the periphery of the first valve hole 522. The first valve seat 525 protrudes downward from the lower surface of the partition wall 52 at the periphery of the first valve hole 522. The third valve seat 523 protrudes upward from the upper surface 521 (see FIG. 2 ) of the partition wall 52 at the periphery of the first valve hole 522.

[0023] The second valve hole 524 is formed as a circular through-hole, and connects the second valve chamber 32 and the vent chamber 33. A second valve seat 526 is provided on the periphery of the second valve hole 524. The second valve seat 526 protrudes downward from the lower surface of the partition wall 52 at the periphery of the second valve hole 524.

[0024] The flange portion 53 is formed to extend outward from the outer peripheral edge of the upper portion of the peripheral wall 51. As shown in FIG. 2, the flange portion 53 has an insertion hole 531. The insertion hole 531 is formed above the locking claw 512 and penetrates the inner peripheral portion of the flange portion 53 in the vertical direction. The locking piece 47 of the cover 4 passes through the insertion hole 531 of the flange portion 53 and engages with the locking claw 512. As shown in FIG. 2, a seal ring 59 is fitted in a groove formed between the flange portion 53 and the partition wall 52.

[0025] The storage wall 54 protrudes upward from the upper surface 521 of the partition wall 52 (i.e., the surface of the partition wall 52 facing the ventilation chamber 33). The storage wall 54 surrounds and accommodates the pressure adjustment valve 6. That is, the space inside the storage wall 54 is formed as a storage section 57 that accommodates the pressure adjustment valve 6. As shown in FIG. 2 , the storage wall 54 has a generally circular frame shape as a whole. However, the shape of the storage wall 54 is not limited to a circular frame shape and may be, for example, a polygonal frame shape such as a square, pentagon, or hexagon, or may be a generally elliptical or oval frame shape. It is preferable that the shape of the storage wall 54 be a shape that matches the outer peripheral shape of the pressure adjustment valve 6. Details of the storage wall 54 will be described later.

[0026] The cover 4 is attached to the top of the housing main body 5 and, together with the partition wall 52 of the housing main body 5, defines the ventilation chamber 33. The cover 4 has a peripheral wall 41, a ceiling wall 42, a flange portion 43, and a fuel vapor pipe 44. The peripheral wall 41 has a substantially cylindrical shape. As shown in FIG. 3 , a fuel vapor outlet 411 is formed at a predetermined location on the peripheral wall 41. The fuel vapor pipe 44 extends outward from the outer surface of the peripheral wall 41 at the outer peripheral edge of the fuel vapor outlet 411 and communicates with the ventilation chamber 33 through the fuel vapor outlet 411. A seal ring 49 is attached to the outer periphery of the fuel vapor pipe 44. A tube (not shown) is connected to the fuel vapor pipe 44 and guides fuel vapor to a canister or the like located outside 102 of the fuel tank 10.

[0027] The ceiling wall 42 is provided on the upper part of the peripheral wall 41 and covers the upper part of the partition wall 52 of the housing main body 5. As shown in Fig. 2, the central part of the ceiling wall 42 extends in a substantially horizontal direction. The portions on both sides of the central part of the ceiling wall 42 slope downward from the central part toward both sides. Note that the shape of the ceiling wall 42 is not limited to the shape exemplified in Fig. 2 and may be, for example, a disk shape.

[0028] The flange portion 43 extends in an annular shape from the lower peripheral edge of the peripheral wall 41. As shown in Fig. 3, the lower end of the flange portion 43 is fixed to the peripheral edge of the mounting hole 103 of the fuel tank 10 by welding or the like, thereby attaching the valve device 2 to the fuel tank 10. Details of the cover 4 will be described later.

[0029] The cap 9 has a peripheral wall 91, a first bottom wall 92, a second bottom wall 93, a first protrusion 94, and a second protrusion 95. The peripheral wall 91 has a generally cylindrical shape. A locking hole 911 is formed in the upper part of the peripheral wall 91. The locking hole 911 is formed as a through-hole extending in the circumferential direction of the peripheral wall 91. As described above, the locking claws 511 of the housing main body 5 are locked into the locking holes 911 of the cap 9, thereby attaching the cap 9 to the lower part of the housing main body 5.

[0030] The first bottom wall 92 is provided midway in the axial direction of the peripheral wall 91 and has a plurality of communication holes (not shown). The first valve chamber 31 communicates with the interior of the fuel tank 10 through the communication holes formed in the first bottom wall 92. The first protrusion 94 protrudes upward from the upper surface of the first bottom wall 92.

[0031] The second bottom wall 93 is provided midway in the axial direction of the peripheral wall 91 and has a plurality of communication holes (not shown). The second valve chamber 32 communicates with the interior of the fuel tank 10 through the communication holes formed in the second bottom wall 93. The second protrusion 95 protrudes upward from the upper surface of the second bottom wall 93.

[0032] The pressure regulating valve 6 is housed inside the vent chamber 33 so as to be able to move up and down, and regulates the pressure inside the interior 101 of the fuel tank 10. Specifically, the pressure regulating valve 6 is housed in a space inside the housing wall 54 of the housing main body 5 (i.e., the housing portion 57) surrounded by the housing wall 54, and is able to move up and down in the direction of axis C (see FIG. 3 ). The direction of axis C is the direction along which the pressure regulating valve 6 moves up and down, and coincides with the axial direction of the housing 3.

[0033] The pressure regulating valve 6 has a disk shape with a predetermined thickness. No through-holes or the like that penetrate the pressure regulating valve 6 in the thickness direction are formed in the pressure regulating valve 6. The shape of the pressure regulating valve 6 is not limited to a disk shape, and may be, for example, a polygonal plate shape such as a square, pentagonal, or hexagonal shape, or may be a substantially elliptical or substantially oval plate shape. The shape of the pressure regulating valve 6 is not particularly limited.

[0034] Examples of materials for the pressure regulating valve 6 include iron-based metal materials such as stainless steel (e.g., SUS304), metal materials such as Ti-based alloys, Cu-based alloys, and Al-based alloys, ceramic materials, and synthetic resin materials. However, the material for the pressure regulating valve 6 is not limited to these, and any material that is resistant to deformation and corrosion due to fuel vapor may be used. The pressure regulating valve 6 in this embodiment is made of stainless steel.

[0035] The pressure regulating valve 6 is biased downward by its own weight. Therefore, the lower surface 61 (see FIG. 5 ) of the pressure regulating valve 6 is normally in contact with the third valve seat 523, causing the pressure regulating valve 6 to close the first valve hole 522. On the other hand, when the lower surface 61 of the pressure regulating valve 6 moves away from the third valve seat 523, the pressure regulating valve 6 opens the first valve hole 522. In this way, the pressure regulating valve 6 opens and closes the first valve hole 522 by moving up and down inside the ventilation chamber 33.

[0036] The first float valve 7 is housed inside the first valve chamber 31 and is movable up and down while being biased upward by a first spring 79 disposed on the first protrusion 94 of the cap 9. The first float valve 7 has a valve head 71. The valve head 71 protrudes upward from the top surface of the first float valve 7 and has a generally conical shape.

[0037] The first float valve 7 opens and closes the first valve hole 522 by rising and falling inside the first valve chamber 31. Specifically, the first float valve 7 closes the first valve hole 522 when the valve head 71 abuts against the inner peripheral edge of the first valve seat 525 of the housing body 5. On the other hand, the first float valve 7 opens the first valve hole 522 when the valve head 71 moves away from the inner peripheral edge of the first valve seat 525 of the housing body 5.

[0038] The second float valve 8 is housed inside the second valve chamber 32 and is movable upward while being biased upward by a second spring 89 disposed on a second protrusion 95 of the cap 9. As shown in Figures 2 and 3, the second float valve 8 has a first float portion 81, a second float portion 82, a third float portion 83, and a seal portion 84. The first float portion 81, the second float portion 82, the third float portion 83, and the seal portion 84 are integrally assembled in this order from bottom to top. The seal portion 84 is made of an elastic material such as rubber and has a generally circular plate shape.

[0039] The second float valve 8 opens and closes the second valve hole 524 by rising and falling inside the second valve chamber 32. Specifically, the second float valve 8 closes the second valve hole 524 when the seal portion 84 abuts against the second valve seat 526 of the housing main body 5. On the other hand, the second float valve 8 opens the second valve hole 524 when the seal portion 84 moves away from the second valve seat 526 of the housing main body 5.

[0040] Next, the valve device 2 according to this embodiment will be further described with reference to the drawings. Fig. 5 is an enlarged cross-sectional view taken along the line A-A in Fig. 2. Fig. 6 is an enlarged cross-sectional view taken along the line B-B in Fig. 1. Fig. 7 is a perspective view showing the housing main body according to this embodiment. Fig. 8 is an enlarged perspective view showing the vicinity of the containing wall according to this embodiment. Fig. 9 is a perspective view of the cover according to this embodiment as viewed obliquely from below. Fig. 5 shows the valve device according to this embodiment in an assembled state, and is an enlarged cross-sectional view showing the vicinity of the pressure adjustment valve 6. Fig. 6 is an enlarged cross-sectional view showing the vicinity of the pressure adjustment valve 6.

[0041] As shown in FIGS. 7 and 8 , the containing wall 54 projects upward from the upper surface 521 of the partition wall 52 , and has a reduced diameter portion 541 , a step portion 542 , and an expanded diameter portion 543 .

[0042] The reduced diameter portion 541 is connected to the upper surface 521 of the partition wall 23, and has a shape that fits the outer periphery of the pressure regulating valve 6. The reduced diameter portion 541 has a circular inner periphery surface 541a that corresponds to the outer periphery (circular shape) of the pressure regulating valve 6, which has a disk shape, and is formed with a constant inner diameter from the upper surface 521 of the partition wall 52 along the direction of the axis C (see FIG. 3 ).

[0043] 5 , when the lower surface 61 of the pressure regulating valve 6 is in contact with the third valve seat 523, the upper end 541b of the reduced diameter portion 541 is located at a position higher than the upper surface 62 of the pressure regulating valve 6. Note that when the lower surface 61 of the pressure regulating valve 6 is in contact with the third valve seat 523, the upper end 541b of the reduced diameter portion 541 may be located at the same height as the upper surface 62 of the pressure regulating valve 6.

[0044] Furthermore, when the pressure regulating valve 6 is raised and the upper surface 62 of the pressure regulating valve 6 abuts against the pedestal 48 (see FIG. 9 ) formed on the ceiling wall 42 of the cover 4, the upper end 541b of the reduced diameter portion 541 is located at a position lower than the lower surface 61 of the pressure regulating valve 6. In other words, when the upper surface 62 of the pressure regulating valve 6 abuts against the pedestal 48, the lower surface 61 of the pressure regulating valve 6 is located at a position higher than the upper end 541b of the reduced diameter portion 541.

[0045] The pedestal 48 protrudes downward from the inner surface of the top wall 42 of the cover 4, and its lower end is capable of abutting against the upper surface 62 of the pressure regulating valve 6. By abutting against the pressure regulating valve 6, the pedestal 48 prevents the pressure regulating valve 6 from rising above the position where it abuts against the pedestal 48. In other words, the pedestal 48 determines the maximum raised position (full stroke position) of the pressure regulating valve 6. Note that the pedestal 48 does not necessarily have to be provided. If the pedestal 48 is not provided, the inner surface of the top wall 42 of the cover 4 determines the maximum raised position (full stroke position) of the pressure regulating valve 6.

[0046] 8, the step portion 542 is connected to the upper end 541b of the reduced diameter portion 541, and is inclined toward the outside of the storage wall 54 as it extends upward from the upper end 541b of the reduced diameter portion 541. In other words, the inner diameter of the storage wall 54 at the step portion 542 increases as it extends upward from the upper end 541b of the reduced diameter portion 541.

[0047] The expanded diameter portion 543 is connected to the upper end of the step portion 542 and has a circular inner circumferential surface. That is, the step portion 542 is provided between the reduced diameter portion 541 and the expanded diameter portion 543 in the direction of the axis C. The expanded diameter portion 543 has a shape that is larger in diameter than the outer circumferential shape of the pressure regulating valve 6, and is formed with a constant inner diameter from the upper end of the step portion 542 along the direction of the axis C.

[0048] 8 , a rib 55 is provided on the expanded diameter portion 543. The rib 55 extends with a constant width along the direction of the axis C from the step portion 542 to the upper end 545 of the accommodating wall 54 (i.e., the upper end of the expanded diameter portion 543). In the housing main body 5 of this embodiment, multiple ribs 55 are arranged at predetermined intervals in the circumferential direction of the expanded diameter portion 543. When viewed along the direction of the axis C, the end (i.e., the inner end) of the rib 55 in the radial direction of the expanded diameter portion 543 is located at the same position as the inner circumferential surface 541 a of the reduced diameter portion 541.

[0049] The storage wall 54 has a slit 544. The slit 544 is formed to extend from an upper end 545 of the storage wall 54 toward the partition wall 52 along the direction of the axis C. The slit 544 may extend from the upper end 545 of the storage wall 54 to the partition wall 52 along the direction of the axis C, or may extend from the upper end 545 of the storage wall 54 to a predetermined position between the upper end 545 and the partition wall 52.

[0050] 8 , a cover wall 56 is provided on the outside of the storage wall 54. The cover wall 56 is provided at a position facing the slit 544 and is connected to the outer surface of the storage wall 54 on both sides of the slit 544. The cover wall 56 protrudes upward from the upper surface 521 of the partition wall 52. The cover wall 56 may extend from the upper surface 521 of the partition wall 52 to the upper end 545 of the storage wall 54, or may extend from the upper surface 521 of the partition wall 52 to a predetermined position between the upper end 545 of the storage wall 54 and the upper surface 521 of the partition wall 52.

[0051] The cover wall 56 has a substantially arc-shaped cross section perpendicular to the direction of the axis C. A cylindrical space is formed inside the cover wall 56. Furthermore, the cover wall 56 has a slit 561. The slit 561 is provided at a position facing the slit 544 of the containing wall 54. The slit 561 is formed to extend from the upper end of the cover wall 56 toward the partition wall 52 along the direction of the axis C. The slit 561 may extend from the upper end of the cover wall 56 to the partition wall 52, or may extend from the upper end of the cover wall 56 to a predetermined position between the upper end of the cover wall 56 and the partition wall 52 along the direction of the axis C.

[0052] 8 , the third valve seat 523 protrudes upward from the upper surface 521 of the partition wall 52 at the periphery of the first valve hole 522. The third valve seat 523 has a minute notch 527 formed along the radial direction of the third valve seat 523. Because the minute notch 527 is formed in the third valve seat 523, the first valve hole 522 is not completely closed even when the lower surface 61 of the pressure adjustment valve 6 is in contact with the third valve seat 523.

[0053] As shown in FIG. 9 , the cover 4 has a protruding wall 45 and a rib 46. The protruding wall 45 protrudes from the inner surface of the ceiling wall 42 toward the partition wall 52 (i.e., downward). As shown in FIGS. 5 and 6 , the protruding wall 45 is arranged around the storage wall 54 of the housing main body 5. In the cover 4 of this embodiment, multiple protruding walls 45 are arranged spaced apart from each other in the circumferential direction of the storage wall 54. In other words, the protruding walls 45 do not surround the entire circumference of the storage wall 54. Note that, as long as the protruding walls 45 are arranged around the storage wall 54 of the housing main body 5, they may or may not surround the entire circumference of the storage wall 54.

[0054] The rib 46 protrudes from the inner surface of the ceiling wall 42 toward the partition wall 52 (i.e., downward). In the direction of the axis C, the lower end 461 of the rib 46 is located at the same position as the lower end 451 of the protruding wall 45. As shown in FIG. 6 , when viewed in the direction of the axis C, the rib 46 extends from the protruding wall 45 side toward the storage wall 54. In this embodiment, the rib 46 is connected to the protruding wall 45 and extends from the protruding wall 45 toward the storage wall 54. Note that the rib 46 does not necessarily have to be connected to the protruding wall 45, and may be provided away from the protruding wall 45.

[0055] 6 , the rib 46 passes through the slit 561 in the cover wall 56 and the slit 544 in the accommodating wall 54, and enters the space inside the accommodating wall 54 (i.e., the accommodating portion 57). When viewed along the direction of the axis C, the end (i.e., the inner end) of the rib 46 in the radial direction of the expanded diameter portion 543 is located at the same position as the inner circumferential surface 541a of the reduced diameter portion 541. In other words, when viewed along the direction of the axis C, the inner end of the rib 46 of the cover 4 is located at the same position as the inner end of the rib 55 of the housing main body 5 in the radial direction of the expanded diameter portion 543.

[0056] Next, the operation of the valve device 2 according to this embodiment will be described with reference to the drawings. As shown in Fig. 3, when the fuel level does not rise in the interior 101 of the fuel tank 10 and the first float valve 7 is not immersed in the fuel, the first float valve 7 is lowered. Therefore, the valve head 71 of the first float valve 7 is separated from the first valve seat 525, and the lower opening of the first valve hole 522 is open. In this state, the second float valve 8 is also lowered in the same manner as the first float valve 7. Therefore, the seal portion 84 is separated from the second valve seat 526, and the second valve hole 524 is open.

[0057] Furthermore, when the pressure inside the fuel tank 10 is below a predetermined value, the pressure regulating valve 6 is biased by its own weight in a direction approaching the third valve seat 523 (i.e., downward). Therefore, the lower surface 61 of the pressure regulating valve 6 abuts against the third valve seat 523, and the upper opening of the first valve hole 522 is closed. At this time, as described above, because the microscopic notch 527 is formed in the third valve seat 523, the first valve hole 522 is not completely closed even when the lower surface 61 of the pressure regulating valve 6 abuts against the third valve seat 523. In the state shown in FIG. 5 , the first valve chamber 31 and the vent chamber 33 are in communication with each other through the first valve hole 522.

[0058] In the state shown in FIG. 5 , when fuel is supplied to the interior 101 of the fuel tank 10 and the opening 96 at the lower end of the cap 9 (i.e., the full tank detection window (see FIG. 3 )) is blocked, gas in the interior 101 of the fuel tank 10 cannot pass through the second valve hole 524. As described above, the lower surface 61 of the pressure regulating valve 6 is always in contact with the third valve seat 523, and the upper opening of the first valve hole 522 is closed. Therefore, gas in the interior 101 of the fuel tank 10 is always unlikely to pass through the first valve hole 522. Therefore, when the opening 96 at the lower end of the cap 9 is blocked by fuel, the second float valve 8 rises and the seal portion 84 comes into contact with the second valve seat 526. As a result, the second float valve 8 closes the second valve hole 524, preventing the tank from becoming full of fuel.

[0059] 5 , when the fuel in the interior 101 of the fuel tank 10 is violently shaken and the fuel level rises, for example, when the vehicle brakes, turns, parks on an incline, or rolls over, the first float valve 7 rises due to the biasing force of the first spring 79 and the buoyancy of the first float valve 7 itself. Then, when the valve head 71 abuts against the inner peripheral edge of the first valve seat 525, the first float valve 7 closes the lower opening of the first valve hole 522. In this situation, the second float valve 8 rises due to the biasing force of the second spring 89 and the buoyancy of the second float valve 8 itself. Then, when the seal portion 84 abuts against the second valve seat 526, the second float valve 8 closes the second valve hole 524. This prevents fuel from passing through the first valve hole 522 and the second valve hole 524 and flowing into the ventilation chamber 33 , and prevents fuel from leaking out to the outside 102 of the fuel tank 10 .

[0060] As described above, the protruding wall 45 of the cover 4 protrudes from the inner surface of the ceiling wall 42 toward the partition wall 52 and is disposed around the storage wall 54 of the housing main body 5. Therefore, even if fuel passes through the first valve hole 522 and flows into the vent chamber 33, the protruding wall 45 functions as a double wall together with the storage wall 54, and can more reliably prevent the fuel from leaking to the outside 102 of the fuel tank 10 through the fuel vapor pipe 44. In other words, the protruding wall 45 can function as a wall that suppresses leakage during dynamic conditions.

[0061] 5 , if fuel vapor increases inside 101 of fuel tank 10 due to, for example, vehicle travel, and the pressure inside 101 of fuel tank 10 rises, fluid such as fuel vapor will try to pass through the vent hole in cap 9, first valve chamber 31, and first valve hole 522 and enter vent chamber 33. This causes the fluid such as fuel vapor to press against lower surface 61 of pressure regulating valve 6, which is in contact with third valve seat 523. This pushes up pressure regulating valve 6, and it rises as far as it can until it comes into contact with base 48 (i.e., performs a full stroke).

[0062] As a result, fluid such as fuel vapor passes through the gap between the outer circumferential surface of pressure regulating valve 6 and the inner circumferential surface of enlarged diameter portion 543 and flows into ventilation chamber 33. The fluid such as fuel vapor that has flowed into ventilation chamber 33 passes through fuel vapor outlet 411 and is guided by a tube connected to fuel vapor piping 44 to a canister or the like located outside 102 of fuel tank 10.

[0063] On the other hand, when the pressure in the interior 101 of the fuel tank 10 decreases, the pressure regulating valve 6 attempts to descend in a direction approaching the third valve seat 523 due to its own weight. At this time, because the slit 544 is formed in the housing wall 54 and the slit 561 is formed in the cover wall 56, fluid such as fuel vapor easily escapes from the inside of the housing wall 54 through the slits 544 and 561 to the outside of the housing wall 54. This makes it possible to increase the valve closing pressure of the pressure regulating valve 6 (the pressure when the increased pressure regulating valve 6 descends and abuts against the third valve seat 523, closing the first valve hole 522 again). This reduces the difference between the valve opening pressure and the valve closing pressure, making it easier to close the pressure regulating valve 6 even when the pressure in the interior 101 of the fuel tank 10 is high.

[0064] As described above, when the pressure in the interior 101 of the fuel tank 10 increases, the pressure regulation valve 6 rises inside the containing wall 54 along the direction of the axis C. On the other hand, when the pressure in the interior 101 of the fuel tank 10 decreases, the pressure regulation valve 6 descends inside the containing wall 54 along the direction of the axis C. At this time, as described above, when viewed along the direction of the axis C, the inner ends of the ribs 55 of the housing main body 5 and the inner ends of the ribs 46 of the cover 4 are located at the same position as the inner circumferential surface 541a of the reduced diameter portion 541. Therefore, the pressure regulation valve 6 is guided in its upward and downward movements by the ribs 55 of the housing main body 5 and the ribs 46 of the cover 4, allowing it to rise and fall stably. In other words, the ribs 55 of the housing main body 5 and the ribs 46 of the cover 4 function to guide the pressure regulation valve 6 as it rises and falls.

[0065] Here, when attaching the cover 4 to the housing main body 5 in the assembly process of the valve device 2, the pressure regulating valve 6 may fall out of the space inside the accommodating wall 54 (i.e., the accommodating portion 57) depending on the attitude of the valve device 2. For example, if the valve device 2 is tilted or if the up-down direction of the valve device 2 is reversed, the pressure regulating valve 6 may fall out of the space inside the accommodating wall 54. In other words, when the cover 4 is attached to the housing main body 5, the base 48 of the cover 4 or the ceiling wall 42 of the cover 4 cannot restrict the maximum raised position of the pressure regulating valve 6, and depending on the attitude of the valve device 2, the pressure regulating valve 6 may fall out of the space inside the accommodating wall 54.

[0066] In contrast, in the valve device 2 according to this embodiment, as described above, the protruding wall 45 of the cover 4 protrudes from the inner surface of the ceiling wall 42 toward the partition wall 52 and is disposed around the storage wall 54 of the housing main body 5. Also, as shown in FIG. 5 , in the direction of the axis C, the lower end 451 (see FIG. 9 ) of the protruding wall 45 is located below the upper end 545 (see FIG. 8 ) of the storage wall 54. Therefore, regardless of the attitude of the valve device 2, the protruding wall 45 can prevent the pressure regulating valve 6 from climbing over the storage wall 54 and falling out of the space inside the storage wall 54. As a result, the valve device 2 according to this embodiment can improve the workability of the assembly process.

[0067] As described above, the ribs 46 of the cover 4 pass through the slits 561 in the cover wall 56 and the slits 544 in the housing wall 54 and enter the space inside the housing wall 54 (i.e., the housing portion 57), and guide the pressure regulating valve 6 as it moves up and down. Therefore, the ribs 46 can maintain the position of the pressure regulating valve 6 while it is moving up and down. As a result, the ribs 46 smoothly lower the pressure regulating valve 6 that has once been raised, and can more reliably return the pressure regulating valve 6 to the lowered position in the space inside the housing wall 54.

[0068] Next, with reference to the drawings, a second state in which the cover 4 is held and temporarily fixed to the housing main body 5 will be described. FIG. 10 is a plan view illustrating the cover of this embodiment in the second state. FIG. 11 is a cross-sectional view taken along the line D-D in FIG. 10 . FIG. 12 is an enlarged cross-sectional view illustrating the cover of this embodiment in the second state. FIG. 13 is an enlarged cross-sectional view illustrating the valve device in the second state with the cover of this embodiment inverted upside down. FIG. 14 is an enlarged cross-sectional view illustrating a first modified example of the cover of this embodiment in the second state. FIG. 15 is an enlarged cross-sectional view illustrating a second modified example of the cover of this embodiment in the second state. Note that FIG. 11 is an enlarged cross-sectional view illustrating the vicinity of the locking claw 512 of the housing main body 5 and the locking piece 47 of the cover 4. FIGS. 12 to 15 correspond to the cross-sectional view taken along the line A-A in FIG. 2 and are enlarged cross-sectional views illustrating the vicinity of the pressure adjustment valve 6.

[0069] In the valve device 2A shown in FIG. 10 , the locking pieces 47 of the cover 4 abut against the locking claws 512 of the housing main body 5, thereby placing the cover 4 in a second state in which it is held and temporarily fixed to the housing main body 5 before transitioning to a first state in which it is permanently fixed to the housing main body 5 (see FIGS. 1 and 4 ). Specifically, as shown in FIG. 11 , when the cover 4 is in the second state, the lower ends of the locking pieces 47 of the cover 4 abut against the upper ends of the locking claws 512 of the housing main body 5. That is, when the cover 4 is in the second state, the locking claws 512 of the housing main body 5 are not engaged with the locking holes 471 formed in the locking pieces 47 of the cover 4. Therefore, as shown in FIG. 12 , the position of the cover 4 in the second state as viewed from the housing main body 5 is higher than the position of the cover 4 in the first state as viewed from the housing main body 5 (see FIG. 5 ).

[0070] Here, as shown in FIG. 12 , when the cover 4 is in the second state, the lower end 451 of the protruding wall 45 is located at a first position lower than the upper end 545 of the storage wall 54 in the direction of the axis C (see FIG. 3 ). Alternatively, as shown in FIG. 14 , when the cover 4 is in the second state, the lower end 451 of the protruding wall 45 may be located at a second position on the same plane S as the upper end 545 of the storage wall 54 in the direction of the axis C. That is, when the cover 4 is in the second state, the lower end 451 of the protruding wall 45 may be located at a second position at the same height as the upper end 545 of the storage wall 54 in the direction of the axis C. Alternatively, as shown in FIG. 15 , when the cover 4 is in the second state, the lower end 451 of the protruding wall 45 may be located at a third position in the direction of the axis C where a gap L2 between the lower end 451 of the protruding wall 45 and the upper end 545 of the storage wall 54 is narrower than the thickness L1 of the pressure regulating valve 6. That is, when the lower end 451 of the protruding wall 45 is in the third position, the gap L2 between the lower end 451 of the protruding wall 45 and the upper end 545 of the containing wall 54 is narrower than the thickness L1 of the pressure regulating valve 6 .

[0071] As described above, when the cover 4 is in the second state, the lower end 451 of the protruding wall 45 is located in any one of the first position shown in Fig. 12, the second position shown in Fig. 14, and the third position shown in Fig. 15 in the direction of the axis C. Therefore, even if the up-down direction of the valve device 2 is reversed as shown in Fig. 13 when the cover 4 is in the second state, the protruding wall 45 can prevent the pressure regulating valve 6 from climbing over the containing wall 54 and falling out of the space inside the containing wall 54. This allows the valve device 2 according to this embodiment to further improve the workability of the assembly process.

[0072] 12 , when the cover 4 is in the second state, the lower end 461 of the rib 46 is located at a first position below the upper end 545 of the containing wall 54 in the direction of the axis C. Alternatively, as shown in FIG. 14 , when the cover 4 is in the second state, the lower end 461 of the rib 46 may be located at a second position on the same plane S as the upper end 545 of the containing wall 54 in the direction of the axis C. That is, when the cover 4 is in the second state, the lower end 461 of the rib 46 may be located at a second position at the same height as the upper end 545 of the containing wall 54 in the direction of the axis C. Alternatively, as shown in FIG. 15 , when the cover 4 is in the second state, the lower end 461 of the rib 46 may be located at a third position in the direction of the axis C where a gap L2 between the lower end 461 of the rib 46 and the upper end 545 of the containing wall 54 is narrower than the thickness L1 of the pressure regulating valve 6. That is, when the lower end 461 of the rib 46 is in the third position, the gap L2 between the lower end 461 of the rib 46 and the upper end 545 of the containing wall 54 is narrower than the thickness L1 of the pressure regulating valve 6 .

[0073] As described above, when the cover 4 is in the second state, the lower end 461 of the rib 46 is located in any one of the first position shown in Fig. 12 , the second position shown in Fig. 14 , and the third position shown in Fig. 15 in the direction of the axis C. Therefore, even if the up-down direction of the valve device 2 is reversed as shown in Fig. 13 when the cover 4 is in the second state, the rib 46 can guide the pressure regulation valve 6 as it moves up and down, and can maintain the position of the pressure regulation valve 6 during the up-down movement. As a result, even if the up-down direction of the valve device 2 is reversed when the cover 4 is in the second state, the rib 46 can smoothly lower the pressure regulation valve 6, which has once risen, and can more reliably return the pressure regulation valve 6 to the lowered position in the space inside the accommodation wall 54.

[0074] The above describes the embodiments of the present invention. However, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the claims. The configurations of the above embodiments can be partially omitted or arbitrarily combined in a different manner from the above.

[0075] 2: Valve device, 2A: Valve device, 3: Housing, 4: Cover, 5: Housing body, 6: Pressure regulating valve, 7: First float valve, 8: Second float valve, 9: Cap, 10: Fuel tank, 23: Partition wall, 31: First valve chamber, 32: Second valve chamber, 33: Vent chamber, 41: Peripheral wall, 42: Ceiling wall, 43: Flange portion, 44: Fuel vapor pipe, 45: Projecting wall, 46: Rib, 47: Locking piece, 48: Base, 49: Seal ring, 51: Peripheral wall, 52: Partition wall, 53: Flange portion, 54: Storage wall, 55: Rib, 56: Cover wall, 57: Storage portion, 59: Seal ring, 61: Lower surface, 62: Upper surface, 71: Valve head, 79: First spring, 81: First float portion, 82: Second float portion, 83: Third float portion, 84: Seal portion, 89: Second spring, 91: Peripheral wall, 92: First bottom wall, 93: Second bottom wall, 94: First protrusion portion, 95: Second protrusion portion, 96: Opening, 101: Interior, 102: Exterior, 103: Mounting hole, 411: Fuel vapor exhaust port, 451: Lower end, 461: Lower end, 471: Locking hole, 511: Locking claw, 512: Locking claw, 521: Upper surface, 522: First valve hole, 523: Third valve seat, 524: Second valve hole, 525: First valve seat, 526: Second valve seat 527: Micro-notch, 531: Insertion hole, 541: Reduced diameter portion, 541a: Inner peripheral surface, 541b: Upper end, 542: Step portion, 543: Expanded diameter portion, 544: Slit, 545: Upper end, 561: Slit, 911: Locking hole

Claims

1. A fuel tank fuel tank comprising: a housing having a valve chamber communicating with the interior of a fuel tank and a vent chamber communicating with the exterior of the fuel tank; a float valve housed in the valve chamber so as to be able to rise and fall; and a pressure regulating valve housed in the vent chamber so as to be able to rise and fall, wherein the housing comprises: a housing main body having a partition wall having a valve hole connecting the valve chamber and the vent chamber, and an accommodating wall protruding from the face of the partition wall facing the vent chamber and surrounding and accommodating the pressure regulating valve; and a cover attached to the top of the housing main body and defining the vent chamber together with the partition wall, wherein the float valve opens and closes the valve hole by rising and falling, and the pressure regulating valve opens and closes the valve hole by rising and falling, and the cover comprises: a ceiling wall covering the upper part of the partition wall, and a protruding wall protruding from the ceiling wall towards the partition and arranged around the accommodating wall, A valve device, characterized in that, in the axial direction in which the pressure regulating valve rises and falls, a lower end of the protruding wall is located at a position lower than an upper end of the containing wall.

2. The valve device described in claim 1, characterized in that: the housing main body further has a first engaging portion; the cover further has a second engaging portion that engages with the first engaging portion; the second engaging portion engages with the first engaging portion, thereby placing the cover in a first state in which it is permanently fixed to the housing main body; the second engaging portion abuts against the first engaging portion before the cover transitions to the first state, thereby placing the cover in a second state in which it is held and temporarily fixed to the housing main body; and when the cover is in the second state, the lower end of the protruding wall is located in one of the following positions in the axial direction when the cover is in the second state: a first position below the upper end of the accommodating wall; a second position on the same plane as the upper end of the accommodating wall; or a third position in which the gap between the lower end of the protruding wall and the upper end of the accommodating wall is narrower than the thickness of the pressure regulating valve.

3. The valve device described in claim 1, characterized in that the storage wall has a slit extending from the upper end toward the partition wall, the cover has a rib protruding from the ceiling wall toward the partition wall, and the rib extends from the protruding wall side toward the storage wall when viewed in the axial direction, passes through the slit and enters the inside of the storage wall, and guides the rising and falling of the pressure regulating valve.

4. The valve device described in claim 3, characterized in that: the housing main body further has a first engagement portion; the cover further has a second engagement portion that engages with the first engagement portion; the second engagement portion engages with the first engagement portion, thereby placing the cover in a first state in which it is permanently fixed to the housing main body; the second engagement portion abuts against the first engagement portion before the cover transitions to the first state, thereby placing the cover in a second state in which it is held and temporarily fixed to the housing main body; and when the cover is in the second state, the lower end of the rib is located in one of the following positions in the axial direction: a first position below the upper end of the accommodating wall; a second position on the same plane as the upper end of the accommodating wall; or a third position in which the gap between the lower end of the rib and the upper end of the accommodating wall is narrower than the thickness of the pressure regulating valve.

Images