JP4854473B2 - Check valve - Google Patents

Description

  The present invention relates to a check valve incorporated in, for example, a fuel supply pipe to a fuel tank of an automobile.

In order to prevent the fuel vapor in the fuel tank of an automobile from being released into the atmosphere during refueling, or to prevent the backflow of fuel, there is known a fuel valve equipped with a check valve. As a check valve that can be used in such a place, the following Patent Document 1 is known.
JP 10-292874 A

  Each of the check valves has a valve body that is formed in a semicircular shape, and the fluid flow path can be opened and closed by assembling the valve body around the hinge pin in the main body. Further, a return coil spring is wound around the hinge pin and urges the valve body in the closing direction.

  As described above, the check valve has a large number of parts, and has a room for improvement because of the high cost and assembling work.

  This invention is completed based on the above situations, Comprising: It aims at providing the non-return valve which can reduce a number of parts and can make an assembly | attachment easy.

As means for achieving the above-mentioned object, the invention of claim 1 includes a housing which is incorporated in a fluid pipe and has a fluid passage which penetrates in the axial direction of the pipe, and the housing. A check valve mounted in a fluid passage and capable of opening and closing the fluid passage, wherein the valve body is a pair of semi-discs each formed of a synthetic resin material a valve plate forming a, and while being opposed diameter portion of the valve plate to butt shape, pivotally mounted to said housing, said two valve plate is displaced in a direction approaching or away from each other Thus, the fluid passage can be opened and closed, and a biasing means is integrally formed on the downstream surface of the fluid in the valve plate so as to be substantially bridged between the two valve plates. , wherein the biasing means is, before Both valve plates are formed by a pair of spring pieces extending in a direction orthogonal to the opposing edges when the two valve plates are opposed to each other, and the spring pieces have ends far from the opposing edges to the valve plates. A fixed end, the end on the near side being a free end, extending obliquely so as to protrude downstream from the fixed end toward the free end, and the both valve plates are the housing When the free ends of the two spring pieces are brought into contact with each other on the central axis of the valve body when the valve plate is rotated in a direction to open the fluid flow path. The both spring pieces are displaced in a direction in which the free end side of the spring pieces protrudes downstream of the valve plate in a direction aligned with the plate surface of the valve plate, thereby returning the valve plate to the direction of returning the valve plate. also characterized in that the biasing force is configured to be prestressed It is.

According to a second aspect of the present invention, in the first aspect of the present invention, the ends of the spring pieces are abutted in a state in which a preload is generated when the valve body is assembled to the housing. The valve plate is held in a pressed state with respect to a sealing surface formed at an outlet side opening edge of the fluid passage in the housing .

According to a third aspect of the present invention, in the first or second aspect of the present invention, the diameter portion of the valve plate is integrally formed with a rotation shaft that is rotatably supported with respect to the housing. It is characterized by being.

According to a fourth aspect of the present invention, there is provided the apparatus according to any one of the first to third aspects, wherein at the opposite edge when the two valve plates are opposed to each other, a rotation shaft is provided at the opposite edge of the one valve plate. A pair of bearing rings having a through hole into which the rotary shaft can be loosely inserted are formed at both ends of the opposite edge of the other valve plate, and are formed between the hole wall of the through hole and the rotary shaft. The ring-shaped space is a die-cutting space when the valve body is integrally formed in a state where the two valve plates are combined with each other .

<Invention of Claim 1>
According to the first aspect of the present invention, when the fluid flows into the fluid passage of the housing, fluid pressure acts on both valve plates, thereby rotating the valve plates toward each other and opening the fluid passage. . The urging means integrally formed on both valve plates is displaced in conjunction with the opening operation of the valve plates, and both the valve plates are urged in the return direction. The valve element closes the fluid passage by the force.

Thus, according to the invention of claim 1 , the spring pieces are integrally formed on both valve plates, and the valve body is closed in the closing direction by being assembled to the housing in a state where the leading ends thereof are abutted against each other. Therefore, the number of parts can be reduced and the entire check valve can be easily assembled. Moreover, since the tips of the spring pieces are brought into contact with each other on substantially the center axis of the valve body, the urging force acting on both valve plates can be balanced.

< Invention of Claim 2 >
According to the invention of claim 2, both the valve plates close the fluid passage while being pressed against the sealing surface of the housing. I will not let you.

< Invention of Claim 3 >
According to the invention of claim 3, since the rotation shaft is also integrally formed with the valve plate, the number of parts is further reduced.

< Invention of Claim 4 >
According to the invention of claim 4, since it is integrally formed with a pair of valve plates assembled, it is possible to reduce manufacturing costs and assembly man-hours.

<Embodiment 1>
A first embodiment of the present invention will be described with reference to FIGS. In FIG. 1, reference numeral 1 denotes a fuel tank of an automobile, and a lower pipe 2 projects from the upper part. On the other hand, an upper pipe 3 is attached so as to communicate with an oil filler port of the automobile body, and the upper and lower pipes 2 and 3 are connected by a rubber hose 4. The connecting portion between the hose 4 and the lower pipe 2 is firmly tightened by a metal hose clamp HC.

  A check valve 5 is incorporated in the projecting end portion from the fuel tank 1 inside the lower pipe 2. The check valve 5 includes a substantially cylindrical housing 6 (made of synthetic resin) that penetrates along the axial direction of the lower pipe 2. The housing 6 is formed in the lower pipe 2 so as to be fitted therein, and the inside thereof is a fluid passage 7. Further, a flange edge 9 is formed so as to project along the entire periphery of the opening edge of one side of the housing 6 (upstream side in the fuel flow direction during refueling). The flange edge 9 is engaged with the projecting end edge of the lower pipe 2 from the outside to regulate the depth at which the housing 6 is fitted into the lower pipe 2. The protruding end edge of the lower pipe 2 swells in a ring shape along the entire circumference, and a mounting edge 10 is formed. Further, three window holes (not shown in detail) pass through at almost equal angular intervals near the flange edge 9 on the peripheral wall of the housing 6, and retaining pieces 8 are provided at the lower edges thereof. Each retaining piece 8 extends obliquely toward the flange edge 9 side, is allowed to bend inward and outward, and can be elastically locked to the mounting edge 10 from the inside. Thus, when the housing 6 is fitted from the upstream end of the lower pipe 2, the mounting edge 10 is locked in a state of being sandwiched between the flange edge 9 and the retaining piece 8. As a result, the housing 6 is fixed to the lower pipe 2. It is assembled so that it cannot move in the axial direction.

  As shown in FIG. 3, the opening edge of the other side of the housing 6 (downstream in the fuel flow direction) is cut away so as to be symmetrical with respect to the axis by a pair of left and right tapered surfaces 11. A horizontal portion 11A is formed between the surfaces 11. When both the valve bodies 12 are in a state in which the fluid passage 7 is closed, the both tapered surfaces 11 come into contact with the peripheral edges of both the valve plates 12A and 12B to seal surfaces (hereinafter, these tapered surfaces are referred to as seal surfaces 11). Function).

A shaft hole 14 through which the shaft end of the rotating shaft 13 is rotatably inserted penetrates coaxially at an intermediate portion between the horizontal portion 11 </ b> A and the flange 9 on the peripheral wall of the housing 6. On the other hand, a support recess 15 that includes the shaft hole 14 and is thinned in the radial direction is formed in a portion where the shaft hole 14 is disposed on the inner surface side of the peripheral wall. The support recess 15 is formed so as to expand toward the downstream side, and a pair of arc-shaped support surfaces 15A are formed above the shaft hole 14, and the die-cut groove portion 16 is formed across the support surfaces 15A. The same type punching groove portion 16 is opened from the opening edge of the flange edge 9 outward with the same depth as the support recess 15. This die-cut groove portion 16 is for forming the above-described support recess 15.
In detail, for the convenience of die cutting at the time of molding, the upper die is molded in a range from the upper surface of the stopper piece 17 described below to the die cutting groove portion 16, and the lower die is formed on both sides of the upper die. A pair of support surfaces 15A of the support recess 15 can be formed.
The come-off prevention piece 17 is provided at a position directly below the shaft hole 14, and the come-off prevention piece 17 is formed to have substantially the same width as the die-cut groove portion 16. A support surface 17A is also formed on the stopper piece 17 and supports the bearing ring 18 of the valve body 12, which will be described later, together with the above-described both support surfaces 15A at three locations. In addition, three reinforcing ribs 19 are arranged at equal angular intervals on the inner surface of the peripheral wall of the housing 6, avoiding the horizontal portion 11 </ b> A. Each of the reinforcing ribs 19 extends vertically over the entire height range of the housing 6. Protrusions are formed.

Next, the valve body 12 will be described. The valve body 12 is formed by two valve plates (made of synthetic resin) having a substantially semi-disc shape, and the edges of the diameter portions (referred to as opposed edges 20A and 20B) are formed. They are facing each other in a butting manner. A pair of bearing rings 18 project from the opposing edges 20A and 20B in the longitudinal direction of one valve plate 12B so as to be orthogonal to the opposing edges 20B. Both bearing rings 18 are formed in an annular shape, and a through hole 21 is formed in the center, and these are positioned coaxially. On the opposite edge 20A of the other valve plate 12A, a pair of rotating shafts 13 project along the length direction with a spring piece 22 described below interposed therebetween, and the shaft ends are outside the valve plate 12A. It is formed so as to protrude slightly. Both rotating shafts 13 have a diameter larger than the thickness of the valve plate 12A, but are formed in a pin shaft shape that is sufficiently smaller in diameter than the through hole 21 of the bearing ring 18, and are arranged coaxially with each other. Further, a notch recess 23 for avoiding interference with the bearing ring 18 when the valve plates 12A and 12B are combined is formed in a portion of the valve plate 12A near the shaft ends of the both rotating shafts 13. Has been.
By the way, in this embodiment, the valve body 12 as a whole is formed with both valve plates 12A and 12B assembled as shown in FIG. That is, the molded shaft is taken out in a state where both the rotating shafts 13 are coaxially inserted into the through holes 21 of the bearing ring 18. Therefore, a ring-shaped space between the rotating shaft 13 and the hole wall of the through hole 21 is a space necessary for punching a mold (not shown) in the axial direction. The other part of the valve body 12 is molded by a pair of molds that open and close in the plate surface direction.

On the other hand, in both valve plates 12A and 12B, an extraction window 24 that is cut out in a U shape in the direction perpendicular to the opposing edges 20A and 20B is opened at the center in the longitudinal direction of the opposing edges 20A and 20B. A spring piece 22 is formed in the extraction window 24. As shown in FIG. 4, both spring pieces 22 extend along a direction orthogonal to the opposing edges 20A and 20B of the valve plates 12A and 12B, the inner end side is a fixed end, and the outer end side is a free end. In addition, the free end is set to a position slightly retracted inward from the axis connecting the two rotation shafts 13. Both spring pieces 22 extend parallel to the valve plate 12A on the fixed end side in the plate thickness direction of both valve plates 12A and 12B, and protrude obliquely outward therefrom, that is, When both the valve plates 12A and 12B are assembled and assembled to the housing 6, they extend so as to protrude downstream, so that an appropriate flexibility is exhibited as a whole. Further, a bent end portion 22 </ b> A is formed at the tip of the spring piece 22 obliquely inward toward the rotation shaft 13. When both valve plates 12A and 12B are in a horizontal state, both bent end portions 22A are in a state of being separated from each other as shown in FIG. However, when the valve body 12 is assembled to the housing 6 and the fluid passage 7 is closed (the state shown in FIG. 2), the bent ends 22A of the two spring pieces 22 are at the position directly below the rotating shaft 13. In this state, a preload is generated such that both valve plates 12A and 12B are pressed against the seal surface 11. When both the valve plates 12A and 12B are rotated so as to open the fluid passage 7 as shown in FIG. 3, the spring pieces 22 are displaced in a direction in which the valve plate and the surface are aligned. The urging force that restores the valve plates 12A and 12B to the closed position is stored.

  Next, the operation and effect of the present embodiment configured as described above will be described in detail. The check valve closes the fluid passage 7 in the housing 6 in a state where no fuel is supplied. That is, in a state where no fuel is supplied, as described above, the bent end portions 22A of the two spring pieces 22 are in a state of being abutted with each other, and are in a state in which preload is generated in the closing direction with respect to the valve body 12, Both valve plates 12 </ b> A and 12 </ b> B are held in pressure contact along the seal surface 11. Thereby, the valve body 12 is maintained in a closed state, and the backflow of fuel from the fuel tank side can be prevented. Further, since the valve body 12 is pressed against the seal surface 11 in a normal state, there is no backlash even when subjected to vibration from the vehicle, and therefore, generation of abnormal noise is prevented in advance.

  Even when the valve body 12 is closed, both sides of the spring piece 22 are slightly opened with the extraction window 24, but there is substantially no problem in preventing backflow of fuel. It is.

  On the other hand, when fuel is supplied from the fuel filler port, fluid pressure accompanying the fueling acts on the plate surfaces of both valve plates 12A and 12B. Thereby, both valve plates 12A and 12B are rotated in the direction in which they approach each other about the rotation shaft 13 (state of FIG. 3). During this time, since the abutting state of the bent end portions 22A gradually increases in both the spring pieces 22, the both spring pieces 22 are displaced from an oblique posture protruding outward from the valve plate to a posture aligned with the plate surface of the valve plate. Therefore, an elastic force is accumulated between the two bent end portions 22A in a direction in which they repel each other. Therefore, when the refueling is stopped and the fluid pressure does not act on the valve plate, the valve body 12 is rotated in the return direction by the elastic force stored between the two spring pieces 22, and the fluid passage 7 is closed again.

  As described above, according to the present embodiment, the urging means for urging the valve body 12 in the closing direction is formed integrally with the valve plates 12A and 12B, so that the number of parts is reduced and the assembly is performed. This can also simplify the work. In particular, in this embodiment, since the rotating shaft 13 and the bearing ring 18 are also formed integrally with the valve plate, the number of parts is further reduced. In addition, the spring piece 22 is disposed on the downstream side of the valve body 12, and the one in this embodiment is displaced so as to be aligned with the plate surfaces of the valve plates 12A and 12B during the opening operation, so that the smoothness of the fuel flow is rather good. It acts to become. Furthermore, since both spring pieces 22 are applied to both valve plates 12A and 12B in a state where the urging force is balanced, the opening and closing operation of the valve body 12 can be performed symmetrically, and this also causes the fuel to flow. Flow smoothness can be achieved.

  Further, in the present embodiment, since the two valve plates 12A and 12B are integrally molded, the molding cost can be reduced as compared with the case of molding individually, and further, the number of parts is reduced and assembled. There is an advantage that it can save the trouble of.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention, and further, within the scope not departing from the gist of the invention other than the following. Various modifications can be made.

  (1) In this embodiment, since the spring pieces 22 are cut and raised from the respective valve plates 12A and 12B, openings are formed on both sides in the width direction of the spring pieces 22, but such openings are not generated. It is also possible to project the spring piece 22 with the entire plate surfaces of both valve plates 12A and 12B closed.

  (2) According to the present embodiment, the spring pieces 22 are individually formed on the valve plate, and the bent end portions 22A are abutted against each other. It is also possible to mold as described.

  (3) In this embodiment, the rotating shaft 13 is formed integrally with the valve plate, but the rotating shaft 13 may be provided separately. Further, the rotary shaft 13 is formed on one valve plate 12A and the bearing ring 18 is formed separately on the other valve plate 12B. Both the rotary shaft 13 and the bearing ring 18 are provided on each valve plate 12A, 12B. May be formed integrally. In that case, the rotation shaft 13 and the bearing ring 18 are arranged at symmetrical positions.

  (4) In this embodiment, the case where the valve body is integrally molded in a state where the valve plates are combined is shown. However, as shown in FIG. Is also possible. In that case, when combining both valve plates 12A and 12B, the valve plates 12A and 12B are squeezed inward in the diametrical direction so as to bring both rotary shafts 13 closer to each other, and the rotary shaft 13 is changed to the other valve. The plate 12B is passed through the corresponding through hole 21 of the bearing ring 18. As a result, both the pivot shafts 13 are inserted in a state of protruding through the bearing ring 18 in a state in which the pivot shafts 13 can freely move (including rotation) with respect to the through holes 21.

Sectional view showing check valve arrangement Cross section of check valve in closed state Cross section of check valve in open state Plan view of the valve body in a single state Plan view showing a state in which the valve body is assembled to the housing The top view which shows the single-piece | unit state of each valve plate in the case of comprising a valve body by assembly | attachment

Explanation of symbols

5 ... Check valve 6 ... Housing 7 ... Fluid passage 12 ... Valve body 12A, B ... Valve plate 13 ... Rotating shaft 22 ... Spring piece

Claims (4)

A housing that is incorporated in a fluid pipe and has a fluid passage that penetrates in the axial direction of the pipe, and a valve body that is mounted in the fluid passage of the housing and can open and close the fluid passage. A check valve comprising:
The valve body has a pair of semi-disc shaped valve plates each formed of a synthetic resin material, and is turned to the housing in a state where the diameter portions of the valve plates face each other in a butting manner. The fluid passage is configured to be movable, and the fluid passage can be opened and closed by displacing the valve plates toward or away from each other, and the downstream surface of the fluid in the valve plate is energized. The means is formed integrally and substantially bridged between the two valve plates,
The urging means is formed by a pair of spring pieces extending in a direction perpendicular to the opposing edges when the two valve boards are opposed to each other, and the spring pieces are at ends far from the opposing edges. The portion is a fixed end to the valve plate, the near end is a free end, and extends obliquely so as to protrude downstream from the fixed end toward the free end, and When both the valve plates are assembled to the housing, the free ends of the two spring pieces are brought into contact with each other on the substantially central axis of the valve body, and the valve plate opens the fluid flow path. In the case of rotating in the direction, the two spring pieces are displaced in a direction aligned with the plate surface of the valve plate from an oblique posture in which the free end side of the spring pieces protrudes downstream of the valve plate, wherein the urging force in the direction to return the valve plate is prestressed Check valve to be. The tips of the spring pieces are abutted in a state in which preload is generated when the valve body is assembled to the housing, so that the both valve plates are formed at the outlet side opening edge of the fluid passage in the housing. The check valve according to claim 1, wherein the check valve is held in a pressed state against the sealed surface . The check valve according to claim 1 or 2, wherein a rotating shaft that is rotatably supported with respect to the housing is formed integrally with the diameter portion of the valve plate . At the opposite edge when the two valve plates face each other, a rotation shaft is formed at the opposite edge of one valve plate, and the rotation shaft can be loosely inserted at both ends of the opposite edge of the other valve plate. A pair of bearing rings having various through holes are formed, and the ring-shaped space between the hole wall of the through hole and the rotating shaft is integrated with the valve body in a state where the two valve plates are combined. The check valve according to any one of claims 1 to 3, wherein the check valve is a die-cutting space for molding .

Images