Relief valve

Abstract

[Problem] Conventional relief valves have the problem wherein resistance increases during valve opening and a valve opening operation is not stable; thus, a countermeasure therefor is required. [Solution] A relief valve 10 in the present embodiment has: a base part 11 that comprises a valve seat 11Z surrounding a valve hole 13; a valve body 35 that has an annular abutment part 35D which abuts the valve seat 11Z; a slide support mechanism 40K that includes a shaft fitting part 31 which supports the valve body 35 to be capable of linear movement in the axial direction of a shaft 40; and a sealing member 21 that is provided to one of the valve seat 11Z or the annular abutment part 35D, where the other thereof comes into contact with the sealing member 21 as a sealing contact part. In the slide support mechanism 40K, the shaft 40 is tilted relative to the shaft fitting part 31 and clearances C1, C2 are provided that allow for a state of partial abutment in which only part of the sealing contact part in the circumferential direction abuts the sealing member 21.

Description

Relief valve

[0001] The present disclosure relates to a relief valve in which a valve element is supported so as to be capable of linear movement.

[0002] Conventionally, a known relief valve of this type has a seal member provided on one of the valve seat and the valve body, and an annular seal portion provided on the other that is in close contact with the seal member (see, for example, Patent Document 1).

[0003] Japanese Utility Model Application Publication No. 6-28991 (see Figure 2)

[0004] However, in relief valves, if the valve is maintained in a closed state for a long period of time, the entire periphery of the seal may adhere to the sealing material. In such cases, conventional relief valves face a problem of increased resistance when opening, resulting in unstable valve opening operation, and a solution to this problem is needed.

[0005] The relief valve of the present disclosure is a relief valve having: a base portion that is placed on the opening edge of a discharge hole of a container and that has a valve hole facing the discharge hole and a valve seat that surrounds the valve hole; a valve body that has an annular abutment portion that abuts the valve seat; a shaft that is provided on one of the valve body or the base portion, and a shaft fitting portion that is provided on the other and fits onto the outside of the shaft; a slide support mechanism that supports the valve body so that it can move linearly in the axial direction of the shaft; and a seal member that is provided on either the valve seat or the annular abutment portion and fits tightly with the other as a seal contact portion, wherein the slide support mechanism is provided with a clearance that allows the shaft to be inclined relative to the shaft fitting portion, resulting in a partial abutment state in which only a portion of the circumferential direction of the seal contact portion abuts the seal member.

[0006] 1 is a perspective view of a relief valve according to a first embodiment of the present disclosure; 2 is an exploded perspective view of the relief valve; 3 is a perspective view of a base portion; 4 is a cross-sectional plan view of the relief valve; 5 is a cross-sectional plan view of a valve seat sealing member; 6 is a perspective view of a valve body; 7 is a partially enlarged cross-sectional side view of a fixing portion of the relief valve to a container wall; 8 is a partially enlarged cross-sectional side view of the relief valve in a closed state; 9 is a partially enlarged cross-sectional side view of the relief valve in an open state; 10 is an enlarged plan view of the relief valve;

[0007] [First Embodiment] FIGS. 1 to 12 show a relief valve 10 according to one embodiment of the present disclosure. The relief valve 10, shown in its entirety in FIG. 1, is stacked and fixed to the outer surface of a container 90. The container 90 illustrated in this embodiment is, for example, a battery pack for a vehicle such as a hybrid vehicle or an electric vehicle, which houses one or more battery cells and protects them from water, dust, and the like. The relief valve 10 of this embodiment is used in the container 90 to prevent the container 90 from bursting in the event of a malfunction such as fluid leakage from a battery cell. The container 90 has, for example, a rectangular parallelepiped shape that is flattened laterally, and includes an elongated container wall 91 on its upper surface, which is partially shown in FIG. 1. A plurality of containers 90 are stacked flat (side by side) and mounted on a vehicle, and the relief valve 10 is attached to the upper surface of each container 90.

[0008] As shown in FIG. 2 , a container wall 91 on the top surface of the container 90 is formed with one drain hole 92 and multiple mounting holes 93 for mounting the relief valve 10. The drain hole 92 is, for example, located at the center of the container wall 91 in the width direction and has an oval shape extending in the longitudinal direction of the container wall 91. The multiple mounting holes 93 are located in pairs on both sides of the drain hole 92 in the longitudinal direction. More specifically, the multiple mounting holes 93 are located between a pair of imaginary lines L1 extending from a pair of opposing linear portions in the width direction of the opening edge of the drain hole 92, and are located closer to the pair of imaginary lines L1. The multiple mounting holes 93 and the drain hole 92 are located and shaped symmetrically in both the width direction and the longitudinal direction of the container wall 91.

[0009] In this embodiment, the container to which the relief valve 10 is attached is the container 90. However, this is not limited to a battery pack, and any container may be used as long as the internal fluid pressure changes. For example, the container to which the relief valve 10 is attached also includes the housing of an air conditioner that contains a refrigerant as a fluid. The container may be made of metal or resin. Furthermore, the container may be either rigid or non-rigid, and may be, for example, a bag-like container that is easily deformable. In this embodiment, the discharge hole 92 is oval, but the shape of the discharge hole 92 may be any shape, such as a circle, an ellipse, a polygon, or an asymmetric irregular shape.

[0010] As shown in Fig. 2, the relief valve 10 has a base portion 11 that is overlapped and fixed to the outer surface (upper surface) of the container wall 91. Hereinafter, for convenience of explanation, the orientations and directions of "the upper side, lower side, side, etc. of the relief valve 10 in Fig. 2" will be simply referred to as the orientations and directions of "the upper side, lower side, side, etc. of the relief valve 10", but the orientations and directions when the relief valve 10 is in use are arbitrary.

[0011] The base portion 11 is, for example, a molded product made of resin, and its planar outer shape is a rectangle with the four corners chamfered in an arc shape (i.e., R-chamfered), which forms the installation space S1 for the relief valve 10. The rectangular planar shape of the base portion 11 is also slightly larger than the rectangle of the container wall 91 that has the multiple mounting holes 93 at its four corners.

[0012] As shown in Fig. 3, the base portion 11 is frame-shaped, with the valve hole 13 on the inside. The valve hole 13 has, for example, a rectangular shape with its four corners chamfered, and a pair of extensions 13A that slightly extend outward from the center of a pair of long sides. As shown in Fig. 4, the distance between the pair of extensions 13A is the same as the width of the discharge hole 92, and the maximum length of the valve hole 13 is greater than the overall length of the discharge hole 92, so that the opening area of ​​the valve hole 13 is wider than that of the discharge hole 92.

[0013] The base portion 11 may be made of metal, and the planar shape of the base portion 11 is not limited to a rectangle, but may be a circle, an ellipse, a polygon other than a rectangle, or the like.

[0014] Adjacent to each of the chamfered surfaces 13C at the four corners of the valve hole 13, a mounting hole 14 is provided. The mounting hole 14 penetrates the base portion 11 from top to bottom and has a female thread 14N on the inside. Specifically, as shown in FIG. 7 , a nut 15 is embedded in the base portion 11 adjacent to each of the chamfered surfaces 13C. That is, the base portion 11 is an insert-molded product with multiple nuts 15 embedded therein. Each nut 15 has a flange 15F that protrudes laterally from its upper end and has an uneven outer circumferential surface. The upper surface of the flange 15F is embedded flush with the upper surface of the base portion 11 (specifically, the upper surface of the annular protrusion 18, described below). The inner surface of the nut 15 forms the female thread 14N of the mounting hole 14.

[0015] The multiple mounting holes 14 form the "fixing portion" of the base portion 11 for fixing the base portion 11 to the container wall 91, and multiple bolts B are passed through the multiple mounting holes 93 in the container wall 91 from inside the container 90 and tightened into the female thread portions 14N of the multiple mounting holes 14 to fix the base portion 11 to the container wall 91. When the base portion 11 is fixed to the container wall 91, the inner surfaces of a pair of expansion portions 13A of the valve hole 13 are positioned so as to be substantially flush with the inner surface of the discharge hole 92, and a pair of inner surfaces of the valve hole 13 that face each other in the longitudinal direction are positioned away from the discharge hole 92, so that substantially the entire discharge hole 92 faces the valve hole 13 (see FIG. 4 ).

[0016] Although the mounting hole 14 described above has a female thread portion 14N, the mounting hole 14 may be a through-hole without a female thread portion 14N, in which case a bolt passed through the mounting hole 14 may be tightened against a nut placed on the upper surface of the base portion 11, or a rivet may be passed through the mounting hole 14 instead of a bolt and its tip may be crimped, or a nut may be fixed coaxially to the mounting hole 93 on the inner surface of the container wall 91, and a bolt inserted into the mounting hole 14 from above may be tightened to the nut. Also, the "fixing portion" of the base portion 11 for fixing the base portion 11 to the container wall 91 does not have to be one through which a fastener such as a bolt or rivet can be passed. For example, the fixing portion may have a plurality of elastic engagement pieces protruding from the base portion 11, and these elastic engagement pieces may engage with the opening edge of the discharge hole 92 or the opening edge of the mounting hole 93 in the container wall 91. Alternatively, the base portion 11 and the container wall 91 may be fixed together with an adhesive, and the portion of the base portion 11 to which the adhesive is applied may be the "fixed portion" of the base portion 11.

[0017] As shown in Fig. 7 , a lower surface groove 16 is formed on the underside of the base portion 11, surrounding the valve hole 13 and the multiple mounting holes 14. The lower surface groove 16 is, for example, a rectangular groove (i.e., has a square cross-sectional shape), and an annular seal member 17 is received therein. As shown in Fig. 2 , the annular seal member 17 is generally in the shape of a rectangular frame plate, and is carved out in the center of the inner edges of the pair of long sides, positions near both ends of the inner edges of the pair of short sides, and a middle portion of the outer edges of the pair of short sides, corresponding to grooves 20 of the base portion 11, which will be described later. The planar shape of the lower surface groove 16 is the same as that of the annular seal member 17. Before the base portion 11 is fixed to the container wall 91, a portion of the annular sealing member 17 protrudes slightly from the underside of the base portion 11, and when the base portion 11 is fixed to the container wall 91, the entire annular sealing member 17 adheres to the outer surface of the container wall 91, surrounding the valve hole 13 from the outside of the multiple mounting holes 14 and sealing the gap between the base portion 11 and the container wall 91.

[0018] The annular sealing member 17 does not have to be a frame-shaped plate as described above, and may be, for example, an O-ring or an adhesive applied between the base portion 11 and the container wall 91. The annular sealing member 17 may be provided so as to surround the valve hole 13 inside the multiple mounting holes 14, and each of the mounting holes 14, 93 may be sealed separately.

[0019] 3, an annular protrusion 18 is formed on the upper surface of the base portion 11. The four corners are rounded and a rectangular area having nuts 15 on the inside of the four corners protrudes upward in a stepped manner to form the annular protrusion 18. The rectangular annular area surrounding the annular protrusion 18 serves as a seal member mounting portion 19.

[0020] The upper surfaces of the annular protrusion 18 and the sealing member mounting portion 19 are flat surfaces parallel to the lower surface of the base portion 11, and the step surface 18D between the annular protrusion 18 and the sealing member mounting portion 19 is approximately perpendicular to the upper surfaces of the annular protrusion 18 and the sealing member mounting portion 19.

[0021] A plurality of grooves 20 are formed on the inner edge of the seal member mounting portion 19. Each groove 20 is a rectangular groove extending along the inner edge of the seal member mounting portion 19. Two grooves 20 are disposed near both ends of each short side of the seal member mounting portion 19, and one groove 20 that is longer than the grooves 20 on the short sides is disposed in the center of each long side of the seal member mounting portion 19. The inner surface of each groove 20 on the annular protrusion 18 side is flush with and continuous with the step surface 18D of the annular protrusion 18.

[0022] As shown in Fig. 8, a valve seat seal member 21 is attached to the seal member mounting portion 19. As shown in Fig. 5, the valve seat seal member 21 has a structure in which a plurality of fitting protrusions 23 hang down from the inner edge of the lower surface of a plate-like, frame-shaped main body portion 22 that is placed on the upper surface of the seal member mounting portion 19.

[0023] The thickness (height) of the main body 22 is slightly smaller than the height of the step surface 18D. The width of the main body 22 is smaller than the width of the seal member mounting portion 19. As shown in Figure 8, the main body 22 fits onto the outside of the annular protrusion 18 and is placed on the upper surface of the seal member mounting portion 19, forming a valve seat 11Z of the base 11.

[0024] As shown in FIG. 5 , the multiple fitting protrusions 23 are provided corresponding to the multiple grooves 20 of the seal member mounting portion 19. The multiple protrusions 23B are provided on the side of a rib 23A that hangs down from the main body 22 and extends along the longitudinal direction of each groove 20. The multiple protrusions 23B extend vertically across the entire height of the rib 23A and have a cross-sectional shape, for example, a flattened semi-ellipse. The multiple protrusions 23B provided on the fitting protrusions 23 reduce the fitting resistance of the fitting protrusions 23 to the grooves 20, facilitating the fitting operation. The multiple protrusions 23B are provided on both the side of the rib 23A facing the annular protrusion 18 and the opposite side, forming a staggered arrangement with the multiple protrusions 23B offset from each other between the two sides. This allows the fitting protrusions 23 to deform slightly in a serpentine manner and easily fit into the grooves 20.

[0025] The valve seat seal member 21 of this embodiment may have, for example, a lip formed on the outer edge of the main body 22 that protrudes toward the valve element 35. In this case, the lip may protrude above the upper surface of the annular protrusion 18. However, regardless of the presence or absence of the lip, it is preferable that the thickness (height) of the inner edge of the main body 22 be flush with or lower than the upper surface of the annular protrusion 18. Furthermore, like the annular seal member 17, the valve seat seal member 21 has a structure in which the fitting protrusion 23 is provided on the plate-shaped, frame-shaped main body 22, but it does not have to have the fitting protrusion 23, and it does not have to be plate-shaped. That is, the valve seat seal member 21 may also be an O-ring, like the annular seal member 17. Furthermore, when the fitting protrusion 23 is provided, the fitting protrusion 23 may be annular and disposed around the entire inner edge of the valve seat seal member 21, and the corresponding groove 20 may be an annular groove. Alternatively, the fitting protrusion 23 may be columnar, e.g., circular, elliptical, or polygonal, and the groove 20 may be replaced with a recess corresponding to the columnar fitting protrusion 23. Furthermore, the multiple protrusions 23B may be provided on only one of the two side surfaces of the rib 23A, or, if provided on both side surfaces of the rib 23A, they may be disposed at the same position between the two side surfaces. The shape of the multiple protrusions 23B is not limited to a vertically extending ridge shape, but may also be, for example, hemispherical. Furthermore, the multiple protrusions 23B may be formed on the inner surface of the groove 20 instead of the fitting protrusions 23. The valve seat seal member 21 and the aforementioned annular seal member 17 may be made of any elastic material, such as rubber, resin, or elastic foam.

[0026] 3, a valve body surrounding wall 25 protrudes upward from the entire outer edge of the base portion 11 (which is also the outer edge of the seal member mounting portion 19). The valve body surrounding wall 25 includes, for example, a plurality of first wall portions 26 arranged at the four corners of the outer edge of the base portion 11, and a plurality of second wall portions 27 arranged between adjacent first wall portions 26 and lower than the first wall portions 26.

[0027] More specifically, the first walls 26 are formed on the outer edge of one of the pair of long sides of the base 11, from a position close to the corner to a position midway along the arc of the corner, and the second walls 27 are formed in the remaining portions. As shown in Fig. 8, the height of the second walls 27 from the top surface of the seal member mounting portion 19 is slightly higher than the annular protrusion 18, and the height of the first walls 26 is, for example, about two to four times the height of the second walls 27.

[0028] As shown in FIG. 3 , a plurality of recesses 28 are formed on the side surface of the base portion 11 below each of the second wall portions 27. As shown in FIG. 8 , each recess 28 is recessed slightly below the top surface of the seal member mounting portion 19 to a position inside the inner surface of the second wall portion 27. Also, as shown in FIG. 3 , the recesses 28 below the pair of second wall portions 27 on the short side are formed in an area excluding both longitudinal ends of the second wall portions 27. Meanwhile, the recesses 28 below the pair of second wall portions 27 on the long side are formed in the entire area excluding the longitudinal center of the second wall portions 27. Furthermore, a slit-shaped drain hole 29 is formed in the base portion 11 through a portion of each recess 28 closer to the valve hole 13 than the inner surface of the second wall portion 27 to the top surface of the seal member mounting portion 19.

[0029] 3, a pair of bridging members 30 spans between a pair of expansion portions 13A of the valve hole 13. The pair of bridging members 30 are strip-shaped and extend parallel to the width direction of the base portion 11, facing each other in the longitudinal direction of the base portion 11. The upper surfaces of the pair of bridging members 30 are flush with the upper surface of the annular protrusion 18, and the lower surfaces of the pair of bridging members 30 are flush with the lower surface of the entire base portion 11.

[0030] A cylindrical shaft fitting portion 31 extending in the vertical direction is provided in the center, which is the centroid of the planar shape of the base portion 11, and is supported by a pair of bridging members 30. The shaft fitting portion 31 is cylindrical with both ends open and has a spring abutment wall 31A that protrudes inward from the upper end. In addition, a pair of recesses 31B are formed in two circumferential locations on the outer surface of the shaft fitting portion 31 near the upper end in the vertical direction, and the pair of bridging members 30 and the shaft fitting portion 31 are molded integrally so that the pair of bridging members 30 are received in the pair of recesses 31B.

[0031] Figure 6 shows the entire valve element 35 of the relief valve 10. The valve element 35 is, for example, a molded product made of resin, and is generally in the shape of a thin dish that bulges upward and opens downward. The planar outline of the valve element 35 is a rectangle similar to but smaller than the planar outline of the base portion 11. Reinforcing ribs 35L are formed on the inner surface of the valve element 35, and a shaft 40 hangs down from the center of the inner surface of the valve element 35. As shown in Figure 9, the valve element 35 is supported slidably in the vertical direction by a slide support mechanism 40K, the main components of which are the shaft fitting portion 31 and the shaft 40 fitted thereto, and is received inside the valve element surrounding wall 25.

[0032] 2, the valve body 35 has a rectangular flat plate portion 35A, a first annular inclined portion 35B that slopes gently downward as it moves away from the flat plate portion 35A, a second annular inclined portion 35C that slopes downward at a greater angle than the first annular inclined portion 35B as it moves away from the first annular inclined portion 35B, a flange portion 35F that protrudes laterally from the lower end of the second annular inclined portion 35C, and an annular abutment portion 35D that protrudes downward from the inner edge of the lower surface shared by the second annular inclined portion 35C and the flange portion 35F as shown in FIG. 9. The reinforcing rib 35L has a lattice pattern, and the lower surface of the reinforcing rib 35L is located midway up and down the second annular inclined portion 35C.

[0033] The annular contact portion 35D has a generally triangular cross section and has a slope that is flush with the inner surface of the second annular inclined portion 35C. When the valve element 35 is positioned in the normal position, which is the ideal position in design, the entire annular contact portion 35D abuts against a portion of the main body 22 of the valve seat sealing member 21 serving as the valve seat 11Z that is outside the fitting protrusion 23.

[0034] The shaft 40 described above has a cylindrical shape and is fitted inside the spring abutment wall 31A of the shaft fitting portion 31. A disk 41 is coaxially attached to the underside of the shaft 40 and screwed to the shaft 40. The outer diameter of the disk 41 is larger than that of the shaft 40 and smaller than the inner diameter of the shaft fitting portion 31. The disk 41 protrudes laterally from the shaft 40 within the shaft fitting portion 31 and faces the spring abutment wall 31A in the vertical direction. A compression coil spring 42 is housed in a tensioned state between the spring abutment wall 31A and the disk 41. As a result, the valve element 35 is supported so as to be able to reciprocate vertically relative to the base portion 11 and is biased toward the valve-closing side, where the valve element 35 abuts against the valve seat 11Z. The bias of the compression coil spring 42 also causes the annular abutment portion 35D of the valve element 35 to bite into the valve seat seal member 21 of the valve seat 11Z.

[0035] 12, the slide support mechanism 40K allows a partial abutment state in which only a portion of the circumferential direction of the annular abutment portion 35D abuts against the valve seat sealing member 21. Specifically, a clearance C1 between the inner surface of the spring abutment wall 31A and the outer surface of the shaft 40, and a clearance C2 between the inner surface of the main body of the shaft fitting portion 31 and the outer surface of the disk 41 allow the shaft 40 to tilt with respect to the shaft fitting portion 31 and the partial abutment state described above.

[0036] In order to restrict the rotation of the valve element 35 around the shaft 40, a rotation restriction mechanism is provided, which mainly comprises a flange portion 35F of the valve element 35 and a side guide portion 45 described below. That is, as shown in Figure 3, one end in the width direction of each of the plurality of first wall portions 26 of the valve element surrounding wall 25 is located at both ends of the straight portions of a pair of long sides of the rectangular planar shape of the valve element surrounding wall 25, and a side guide portion 45 protrudes from the inner surface of one end in the width direction of each of the first wall portions 26.

[0037] 9, the tip surface of each side guide portion 45 facing the valve body 35 forms a vertical surface 45A parallel to the vertical direction from the bottom end to a midpoint in the vertical direction, and forms an inclined surface 45B from the midpoint to the top end that slopes upward so as to move away from the valve body 35. The boundary between the vertical surface 45A and the inclined surface 45B is located slightly below the top surface of the second wall portion 27 of the valve body surrounding wall 25.

[0038] 10, when the relief valve 10 is viewed from above, the ends of the straight portions of a pair of long sides of the rectangular planar shape of the valve body 35 face one side of the midpoint in the width direction of each side guide portion 45, and the R-chamfered portions of the corners of the rectangular planar shape of the valve body 35 face the other side of the midpoint in the width direction of each side guide portion 45. This prevents one of the valve body 35 and the side guide portion 45 from biting into the other.

[0039] 8, the tip surface of the flange portion 35F of the valve disc 35 includes a vertical surface 46A above a midpoint in the vertical direction and an inclined surface 46B below the vertical surface 46A. The vertical surface 46A is generally parallel to the vertical direction, and the inclined surface 46B is inclined downward toward the annular abutment portion 35D. The intersection of the vertical surface 46A and the inclined surface 46B forms an obtuse corner 35K that juts out toward the side guide portion 45. When the annular abutment portion 35D of the valve disc 35 is engaged with the valve seat seal member 21, the upper surface of the flange portion 35F of the valve disc 35 is located at approximately the same height as the boundary between the vertical surface 45A and the inclined surface 45B, and the vertical surface 46A of the valve disc 35 faces the vertical surface 45A of the side guide portion 45 with a small gap therebetween.

[0040] This completes the description of the configuration of the relief valve 10 of this embodiment. Next, the operation and effect of the relief valve 10 will be described. As shown in FIG. 7 , when the base portion 11 of the relief valve 10 is fixed to the container wall 91, the gap between the base portion 11 and the container wall 91 is sealed by the annular seal member 17 sandwiched therebetween. Here, the annular seal member 17 surrounds the valve hole 13 at a position farther from the valve hole 13 than the multiple mounting holes 14 in the base portion 11. Furthermore, the valve seat seal member 21 of the valve seat 11Z, which seals between the base portion 11 and the valve disc 35, also surrounds the valve hole 13 at a position farther from the valve hole 13 than the multiple mounting holes 14. Therefore, the annular seal member 17 and the valve seat seal member 21 can seal not only the gap between the container 90 and the base portion 11 but also the multiple mounting holes 14, 93 in the base portion 11 and the container wall 91.

[0041] Furthermore, the relief valve 10 has multiple nuts 15 embedded in the base portion 11, and the inside of each of these nuts 15 forms a female screw portion 14N within the mounting hole 14, making it easier to attach the relief valve 10 to the container 90 than if the nuts 15 were provided separately from the base portion 11.

[0042] In the relief valve 10, under normal conditions where the pressure inside the container 90 is equal to or lower than a predetermined pressure, the annular contact portion 35D of the valve element 35 is pressed against the valve seat seal member 21 of the valve seat 11Z by the elastic force of the compression coil spring 42, thereby maintaining the valve in a closed state. When the pressure inside the container 90 exceeds a predetermined pressure that overcomes the elastic force of the compression coil spring 42, the valve is opened. The container 90 to which the relief valve 10 of the present embodiment is attached houses battery cells, as described above. In the event of a malfunction in which fluid leaks from a battery cell, the pressure inside the container 90 may suddenly rise. In contrast, the relief valve 10 of the present embodiment has the valve seat 11Z disposed so as to surround the mounting hole 14 for fixing the base portion 11 to the container 90, as described above. Therefore, compared to conventional relief valves in which the mounting hole 14 is located outside the valve seat 11Z, the circumferential length of the valve seat 11Z is longer, and the flow rate of fluid that can be discharged can be increased, given the same installation space. As a result, the relief valve 10 of this embodiment changes from the closed state shown in FIG. 8 to the open state shown in FIG. 9 and simultaneously discharges a large amount of fluid at once, thereby responding to a sudden increase in pressure inside the container 90.

[0043] Furthermore, the valve element 35 of the relief valve 10 is shaped to bulge on the side away from the valve hole 13, so that it can easily receive the dynamic pressure of the fluid in the open state, and the valve element 35 can easily move to the valve opening side. Moreover, the valve hole 13 of the relief valve 10 is wider than the discharge hole 92. These factors also make it possible to discharge a large amount of fluid all at once immediately after the valve element 35 opens.

[0044] Furthermore, in the relief valve 10 of this embodiment, the tip surface of the annular protrusion 18, which is located between the valve seat seal member 21 and the valve hole 13, is located further ahead in the protruding direction of the annular protrusion 18 than the valve seat seal member 21, so the valve seat seal member 21 is not directly subjected to the dynamic pressure of the fluid being discharged from the valve hole 13. As a result, even if a large flow rate of fluid is discharged all at once when the valve is opened, the valve seat seal member 21 is prevented from coming off due to the dynamic pressure of the fluid.

[0045] Furthermore, the base portion 11 is provided with a groove 20 on the outside of the annular protrusion 18, and the fitting protrusion 23 of the valve seat seal member 21 fits into the groove 20, which also makes it difficult for the valve seat seal member 21 to come off. Furthermore, the fitting protrusion 23 is formed with a plurality of protrusions 23B, which further makes it difficult for the valve seat seal member 21 to come off. Moreover, the plurality of protrusions 23B extend in the fitting direction relative to the groove 20, which makes it easy to fit the fitting protrusion 23 into the groove 20.

[0046] 9, the fluid guide portion 35G, which is the inner surface of the second annular inclined portion 35C of the valve body 35, guides the discharged fluid from above toward the valve seat seal member 21, so that the dynamic pressure of the fluid acts in a direction that deepens the fit of the valve seat seal member 21 with the annular protrusion 18. This also prevents the valve seat seal member 21 from coming off due to the dynamic pressure of the fluid.

[0047] Furthermore, the relief valve 10 of this embodiment is provided with side guide portions 45 that restrict rotation of the valve element 35, separate from the slide support mechanism 40K that supports the valve element 35 so that it can move linearly, thereby reducing the load on the slide support mechanism 40K and enabling smooth movement of the valve element 35. Moreover, the side guide portions 45 laterally face the valve element 35 and are positioned away from the slide support mechanism 40K, so that rotation of the valve element 35 can be effectively suppressed.

[0048] Furthermore, as shown in Figure 8, the valve body 35 has a flange portion 35F that protrudes laterally toward the side guide portion 45, and the tip surface of the flange portion 35F is provided with an obtuse corner portion 35K that protrudes toward the side guide portion 45, thereby preventing the valve body 35 from coming into face contact with the side guide portion 45 and reducing frictional resistance between the valve body 35 and the side guide portion 45 when the valve body 35 moves in a straight line.

[0049] 11 , the inner surface of the side guide portion 45 is provided with an inclined surface 45B that inclines away from the valve element 35 as it moves away from the base portion 11. This causes the gap between the inner surface of the side guide portion 45 to widen as the valve element 35 opens. This prevents foreign matter X from getting caught between the valve element 35 and the side guide portion 45, locking the valve element 35 in the closed state. Furthermore, the inclined surface 45B faces the tip surface of the flange portion 35F in the closed state. This causes the gap between the tip surface of the flange portion 35F and the inner surface of the side guide portion 45 to widen even when the valve element 35 opens slightly from the closed state, allowing the valve element 35 to easily open from the closed state even if foreign matter X is caught in the gap.

[0050] 1, the valve element 35 is surrounded by the valve element surrounding wall 25 that protrudes from the base portion 11, so that it is protected from collisions with foreign objects, etc. Furthermore, the side of the valve element surrounding wall 25 that is away from the base portion 11 is open, and no valve-opening-side opposing wall that faces the valve element 35 from the valve-opening side is provided, so that problems such as foreign objects getting caught between the valve element 35 and the valve-opening-side opposing wall and locking the valve element 35 in the closed state are prevented.

[0051] In addition, the valve body surrounding wall 25 includes a plurality of first wall portions 26 and a plurality of second wall portions 27 that are lower than the first wall portions 26, thereby protecting the valve body 35 while reducing the resistance to fluid discharge when the valve is opened.

[0052] 8, even if water enters the valve body surrounding wall 25, it is drained out through the drain hole 29, preventing water from entering the container 90 when the valve is open. Moreover, the opening width W1 of the drain hole 29 is narrower than the distance W2 between the valve body 35 and the valve body surrounding wall 25 when the valve is closed. Therefore, when the valve body 35 is slightly open and fluid is discharged from the valve hole 13, more of the fluid flows toward the gap between the valve body 35 and the valve body surrounding wall 25 than toward the drain hole 29. Therefore, if foreign matter X (see FIG. 11) such as dust is caught between the valve body 35 and the valve body surrounding wall 25, the foreign matter can be blown away from the gap to the side opposite the drain hole 29.

[0053] Incidentally, if the relief valve 10 is maintained in a closed state for a long period of time, the valve seat seal member 21 may adhere to the annular contact portion 35D of the valve body 35. In response to this, the slide support mechanism 40K of the relief valve 10 of the present embodiment allows a partial abutment state in which only a portion of the circumferential direction of the annular abutment portion 35D abuts against the valve seat seal member 21. As a result, when the valve is opened from a state in which the entire periphery of the annular abutment portion 35D is in contact with the valve seat seal member 21, the valve body 35 tilts and the annular abutment portion 35D gradually separates from the valve seat seal member 21, thereby reducing resistance when the valve is opened and stabilizing the valve opening operation.

[0054] Second Embodiment A second embodiment of the present disclosure will be described below with reference to FIG. 13 . As shown in FIG. 13 , a relief valve 10B of this embodiment differs from the relief valve 10 of the first embodiment in that a clearance C3 is provided only in the longitudinal direction of the planar shape of the valve disc 35. The clearance C3 allows a partial abutment state in which only a portion of the circumferential direction of the annular abutment portion 35D abuts against the valve seat seal member 21. Specifically, in the relief valve 10B of this embodiment, the planar cross-sectional shape of the shaft fitting portion 31 including the spring abutment wall 31A is an ellipse that is longer in the longitudinal direction of the rectangular planar shape of the valve disc 35, thereby providing the above-mentioned clearance C3. The other configurations are the same as those of the relief valve 10 of the first embodiment. The relief valve 10B of this embodiment also achieves the same effects as the relief valve 10 of the first embodiment.

[0055] [Third Embodiment] A third embodiment of the present disclosure will be described below with reference to Figures 14 and 15. As shown in Figure 14, a relief valve 10C of this embodiment differs from the relief valve 10 of the first embodiment in that the arrangement of the shaft 40 and the shaft fitting portion 31 that fits therewith is shifted from their arrangement in the relief valve 10 of the first embodiment. Specifically, in the relief valve 10 of the first embodiment, the center of the shaft 40 is positioned to overlap with the centroid P1 of the area surrounded by the valve seat 11Z when viewed in the axial direction of the shaft 40. However, in the relief valve 10C of this embodiment, the center P2 of the shaft 40 is shifted from the centroid P1 of the area surrounded by the valve seat 11Z in the longitudinal direction of the area. Furthermore, in this embodiment, as shown in Figure 15, the compression coil spring 42 is, for example, a tapered coil spring whose diameter increases upward. This reliably prevents the compression coil spring 42 from being pinched between the inner surface of the spring abutment wall 31A and the shaft 40. The configuration other than that described above is the same as that of the relief valve 10 of the first embodiment.

[0056] According to the configuration of this embodiment, the valve element 35 is inclined relative to the linear movement direction when subjected to pressure within the container 90, and resistance when the valve is opened is reduced.

[0057] [Fourth Embodiment] Hereinafter, a fourth embodiment of the present disclosure will be described with reference to Figures 16 and 17. As shown in Figure 16, a relief valve 10D of this embodiment differs from the relief valve 10 of the first embodiment only in the shape of the valve hole 13. That is, in the relief valve 10D of this embodiment, the valve hole 13 of the relief valve 10 of the first embodiment (hereinafter referred to as the "original valve hole 13") is blocked by a wall body 38 over a range from one bridging member 30 to one end of the valve hole 13, and a valve hole 13V is formed in the wall body 38 at a position facing the discharge hole 92. The valve hole 13W, which is the portion of the original valve hole 13 that is not blocked by the wall body 38, and the valve hole 13V together form the valve hole 13X of the entire relief valve 10D. As a result, when viewed in the axial direction of the shaft 40, the centroid P1 of the area surrounded by the valve seat 11Z and the centroid P3 of the valve hole 13X are misaligned. The configuration other than that described above is the same as that of the relief valve 10 of the first embodiment.

[0058] According to the relief valve 10D of this embodiment, when the pressure inside the container 90 suddenly rises, the dynamic pressure of the fluid flowing through the container 90 acts unevenly on the valve element 35, causing the valve element 35 to tilt as shown in FIG. 17, thereby reducing the resistance when the valve is opened.

[0059] Fifth Embodiment A fifth embodiment of the present disclosure will be described below with reference to FIG. 18 . As shown in FIG. 18 , in a relief valve 10E of this embodiment, the valve element 35 of the relief valve 10 of the first embodiment is divided into a shaft 40 and a valve element main body 35H, and the upper end of the shaft 40 is connected to the valve element main body 35H via a hinge portion 40H. That is, the hinge portion 40H is included in a slide support mechanism 40K. The rotation axis of the hinge portion 40H extends in the short direction of the rectangular planar shape of the valve element 35. Furthermore, the clearance between the shaft 40 and the shaft fitting portion 31 is smaller than that of the relief valve 10 of the first embodiment, so that the shaft 40 does not tilt relative to the shaft fitting portion 31 as much as in the relief valve 10 of the first embodiment. The hinge portion 40H allows the valve body 35H to tilt and enter a partial abutment state in which only a portion of the annular abutment portion 35D in the circumferential direction abuts against the valve seat sealing member 21. The relief valve 10E of the present embodiment also achieves the same effects as the relief valve 10 of the first embodiment.

[0060] Sixth Embodiment A sixth embodiment of the present disclosure will now be described with reference to FIG. 19 . Although the overall shape of a relief valve 10F of this embodiment is not shown, it is the same as, for example, the relief valve 10 of the first embodiment, with only the surface roughness of the annular contact portion 35D being different. That is, as shown in FIG. 19 , the annular contact portion 35D of the relief valve 10F of this embodiment has a triangular cross section, similar to the relief valve 10 of the first embodiment, and is configured to fit into the valve seat seal member 21 from its tip (lower end) to a vertically intermediate position. That is, the contact area S2 with the valve seat seal member 21 is the area between the tip of the annular contact portion 35D and a vertically intermediate position of the annular contact portion 35D on both the inner and outer sides. Furthermore, within the contact area S2, the base-end region S4 of the annular contact portion 35D has a larger surface roughness than the tip-end region S3. Specifically, the entire surface of the annular contact portion 35D, except for the tip-end region S3, is textured.

[0061] According to the relief valve 10F of the present embodiment, the base end side of the contact area S2 of the annular abutment portion 35D with the valve seat seal member 21 has a larger surface roughness than the tip end side, so resistance when the valve is opened is reduced compared to when the contact area S2 has the same surface roughness and is in similar close contact with the valve seat seal member 21. The configuration of the annular abutment portion 35D of the present embodiment may be applied to the relief valves 10B to 10E of the second to fifth embodiments.

[0062] [Seventh Embodiment] Although the shape of the relief valve of this embodiment is not illustrated, it is the same as, for example, the relief valve 10 of the first embodiment, and the surface roughness of the annular abutment portion 35D is different so as to be unbalanced in the circumferential direction. The surface roughness of the annular abutment portion 35D on one side of the longitudinal center of the rectangular planar shape of the valve body 35 is rougher than the surface roughness of the annular abutment portion 35D on the other side.

[0063] In the relief valve of this embodiment, the annular contact portion 35D gradually separates from the valve seat sealing member 21 starting from the portion with a rough surface roughness, thereby reducing resistance when the valve is opened. The configuration of the annular contact portion 35D of this embodiment may be applied to the relief valves 10B to 10E of the second to sixth embodiments.

[0064] [Other Embodiments] (1) In the relief valves 10, 10B to 10E of the above embodiments, the planar shapes of the valve seat 11Z and the valve body 35 are rectangular, but this is not limited to this and may be polygonal other than rectangular, circular, elliptical, or an irregular shape that does not have a shaped surface.

[0065] (2) In addition, in the relief valves 10, 10B to 10E of the above embodiments, the valve element 35 is supported so as to be able to move linearly. However, the valve element 35 may be rotated to open and close, or the valve element 35 itself may be elastically deformed so that the annular abutment portion, which is its outer edge, approaches and moves away from the valve seat 11Z.

[0066] (3) In the relief valves 10, 10B to 10E of the above embodiments, a seal member (valve seat seal member 21) is provided on the valve seat 11Z out of the valve body 35 and the valve seat 11Z. However, the seal member may be provided on the valve body 35 side.

[0067] <Supplementary Notes> Below, the group of features extracted from the above embodiment will be explained, indicating, as necessary, the effects, etc. Note that, for ease of understanding, the symbols of corresponding configurations in the above embodiment will be indicated in parentheses as appropriate below, but these group of features are not limited to the specific configurations identified by the symbols indicated in parentheses, etc.

[0068] <First Feature Group> [Feature 1] A relief valve (10, 10B to 10E) comprising: a base portion (11) that is placed on an opening edge of a discharge hole (92) of a container (90) and has a valve hole (13, 13X) that faces the discharge hole (92); a fixing portion (14) that is provided on the base portion (11) and that fixes the base portion (11) to the container (90); a valve seat (11Z) that is provided on the base portion (11) and surrounds the valve hole (13, 13X) at a position farther from the valve hole (13, 13X) than the fixing portion (14); and a valve body (35) that is disposed opposite the valve hole (13, 13X) and has an annular abutment portion (35D) that moves toward and away from the valve seat (11Z).

[0069] In the relief valve (10, 10B to 10E) of Feature 1, the valve seat (11Z) is disposed so as to surround the fixing portion (14) for fixing the base portion (11) to the container. Therefore, compared to conventional relief valves in which the fixing portion (14) is disposed outside the valve seat (11Z), the circumferential length of the valve seat (11Z) is longer for the same installation space (S1), thereby enabling a larger flow rate of the dischargeable fluid. In other words, the relief valve (10, 10B to 10E) of Feature 1 makes it possible to increase the flow rate of the dischargeable fluid while minimizing the expansion of the installation space (S1) compared to conventional relief valves. The valve disc (35) may be one that moves linearly, one that rotates, or one in which the valve disc (35) itself elastically deforms so that an annular abutment portion (35D), which is the outer edge of the valve disc (35), approaches and moves away from the valve seat (11Z).

[0070] [Feature 2] The relief valve (10, 10B to 10E) according to Feature 1, further comprising: an annular sealing member (17) that is sandwiched between the container (90) and the base portion (11) and surrounds the valve hole (13, 13X) at a position farther from the valve hole (13, 13X) than the fixing portion (14) is.

[0071] In the relief valve (10, 10B to 10E) of feature 2, the annular sealing member (17) sandwiched between the container (90) and the base portion (11) surrounds the valve hole (13, 13X) at a position farther from the valve hole (13, 13X) than the fixing portion (14) does. Therefore, when the container (90) is provided with an attachment hole (93) corresponding to the fixing portion (14), the annular sealing member (17) can seal the attachment hole (93) in addition to sealing between the container (90) and the base portion (11).

[0072] [Feature 3] The relief valve (10, 10B to 10E) according to Feature 2, wherein the fixing portion (14) includes a plurality of mounting holes (14) through which a plurality of rod-shaped fasteners passing through the container (90) are inserted.

[0073] Examples of the fixing portion (14) include an adhesive that bonds the base portion (11) and the container (90), an elastic engagement piece that protrudes from the base portion (11) and engages with the opening edge of the discharge hole (92), and the configuration of Feature 2. The configuration of Feature 2 allows the base portion (11) to be easily and firmly fixed to the container (90).

[0074] [Feature 4] The relief valve (10, 10B to 10E) according to Feature 3, wherein the base portion (11) is a molded product having a plurality of nuts embedded therein, the plurality of rod-shaped fasteners are a plurality of bolts (B), and the plurality of mounting holes (14) include female thread portions (14N) of the plurality of nuts (15) into which the plurality of bolts (B) are threaded.

[0075] In the relief valve (10, 10B to 10E) having this characteristic, a nut (15) having a female screw portion (14N) for fixing the base portion (11) to the container (90) is embedded in the base portion (11), so that the installation work to the container (90) can be performed more easily than when the nut (15) is provided separately from the base portion (11).

[0076] [Feature 5] The relief valve (10, 10B to 10E) according to any one of Features 1 to 4, wherein the valve body (35) has a shape that bulges outward on a side away from the valve hole (13, 13X).

[0077] In the relief valve (10, 10B to 10E) of feature 5, the valve element (35) has a shape that bulges on the side away from the valve hole (13, 13X), so that the dynamic pressure of the fluid can be easily received in the open state, and the valve element (35) can easily move to the valve opening side. This makes it possible to discharge a large flow rate of fluid all at once immediately after the valve element (35) opens.

[0078] [Feature 6] The relief valve (10, 10B to 10E) according to any one of Features 1 to 5, wherein the valve seat (11Z) and the valve element (35) each have a non-circular planar shape, and the relief valve (10, 10B to 10E) includes: a slide support mechanism (40K) that supports the valve element (35) so as to be linearly movable in the axial direction of the shaft (40), and a lateral guide portion (45) that protrudes from the base portion (11), faces the valve element (35) from a side, and restricts rotation of the valve element (35) around the shaft (40).

[0079] In the relief valve (10, 10B to 10E) of Feature 6, a side guide portion (45) that restricts rotation of the valve element (35) is provided separately from a slide support mechanism (40K) that supports the non-circular valve element (35) so that the valve element (35) can move linearly, thereby reducing the load on the slide support mechanism (40K) and enabling smooth movement of the valve element (35). Moreover, the side guide portion (45) laterally faces the valve element (35) and is positioned away from the slide support mechanism (40K), thereby effectively restricting rotation of the valve element (35).

[0080] [Feature 7] The relief valve (10, 10B to 10E) according to Feature 6, wherein the valve seat (11Z) and the valve disc (35) each have a rectangular planar shape, and the surfaces (45A, 45B) of the side guide portion (45) facing the valve disc (35) are parallel to one side of the rectangular planar shape of the valve seat (11Z) and face one side of the rectangular planar shape of the valve disc (35) when viewed from the linear movement direction of the valve disc (35).

[0081] According to the configuration of feature 7, one of the valve body (35) and the side guide portion (45) is prevented from biting into the other.

[0082] [Feature 8] The relief valve (10, 10B to 10E) according to any one of Features 6 to 8, wherein the valve body (35) has a flange portion (35F) that protrudes laterally toward the side guide portion (45), and a tip surface of the flange portion (35F) is divided at a midpoint in the moving direction of the valve body (35), and the divided portion is provided with an obtuse-angled corner portion (35K) that protrudes toward the side guide portion (45).

[0083] According to the configuration of feature 8, the valve body (35) is prevented from coming into face contact with the side guide portion (45), and frictional resistance between the valve body (35) and the side guide portion (45) when the valve body (35) moves linearly is reduced.

[0084] [Feature 9] The relief valve (10, 10B to 10E) according to any one of Features 6 to 8, wherein the valve body (35) has a flange portion (35F) that protrudes laterally toward the side guide portion (45), and an inner surface of the side guide portion (45) is provided with an inclined surface (45B) that inclines so as to move away laterally from the tip surface of the flange portion (35F) as the distance from the base portion increases in the linear movement direction of the valve body (35).

[0085] In the relief valve (10, 10B to 10E) of feature 9, the inner surface of the side guide portion (45) is provided with an inclined surface (45B) that inclines so as to move away from the valve body (35) as it moves away from the base portion (11), so that the gap between the inner surface of the side guide portion (45) widens as the valve body (35) opens. This prevents foreign matter from getting caught between the valve body (35) and the side guide portion (45) and locking the valve body (35) in a closed state.

[0086] [Feature 10] The relief valve (10, 10B to 10E) according to Feature 9, wherein the inclined surface (45B) faces a tip end surface of the flange portion (35F) in a closed state.

[0087] In the configuration of feature 10, the inclined surface (45B) of the side guide portion (45) faces the side surface of the flange portion (35F) in the closed state, so that when the valve body (35) is only slightly opened from the closed state, the gap between the valve body (35) and the inner surface of the side guide portion (45) widens, and the valve body (35) can easily open from the closed state even if a foreign object is caught in the gap.

[0088] [Feature 11] The relief valve (10, 10B to 10E) according to any one of Features 1 to 10, further comprising a valve body surrounding wall (25) that protrudes from the base portion (11) and surrounds the valve body (35) from a side, and the side of the valve body surrounding wall (25) that is away from the base portion (11) is open.

[0089] In the relief valve (10, 10B to 10E) of feature 11, the valve element (35) is protected by being surrounded from the side by the valve element surrounding wall (25). Furthermore, the valve element surrounding wall (25) is open on the side away from the base portion (11) and does not have a valve-opening-side opposing wall that faces the valve element (35) from the valve-opening side, thereby preventing a problem such as a foreign object getting caught between the valve element (35) and the valve-opening-side opposing wall, which would lock the valve element (35) in a closed state.

[0090] [Feature 12] The relief valve (10, 10B to 10E) according to Feature 11, wherein the valve body surrounding wall (25) includes a plurality of first wall portions (26) distributed at a plurality of locations in the circumferential direction of the valve body surrounding wall (25), and a plurality of second wall portions (27) provided between the first wall portions (26) and lower than the first wall portions (26).

[0091] In the relief valve (10, 10B to 10E) of feature 11, the valve body surrounding wall (25) includes a plurality of first wall portions (26) and a plurality of second wall portions (27) that are lower than the first wall portions (26), so that the discharge resistance of the fluid when the valve is opened is reduced while protecting the valve body (35).

[0092] [Feature 13] The relief valve (10, 10B to 10E) according to Feature 11 or 12, further comprising a drain hole (29) that has an opening that penetrates the base portion (11) and is located between the valve body surrounding wall (25) and the valve seat (11Z), and that drains water that has entered the valve body surrounding wall (25).

[0093] According to the relief valve (10, 10B to 10E) of feature 13, water that has entered the valve body surrounding wall (25) is discharged to the outside of the valve body surrounding wall (25) through the drain hole (29), thereby preventing water from entering the container (90) when the valve is opened.

[0094] [Feature 14] The relief valve (10, 10B to 10E) according to Feature 13, wherein an opening of the drain hole (29) extends along the valve body surrounding wall (25), and the opening width is narrower than a distance between the valve body (35) and the valve body surrounding wall (25) in a closed state.

[0095] In the relief valve (10, 10B to 10E) of feature 14, the opening width of the drain hole (29) is narrower than the gap between the valve disc (35) and the valve disc surrounding wall (25) in the closed state. As a result, when the valve disc (35) is slightly open and fluid is discharged from the valve hole (13, 13X), more of the fluid flows toward the gap between the valve disc (35) and the valve disc surrounding wall (25) than toward the drain hole (29). If dust or other foreign matter is caught between the valve disc (35) and the valve disc surrounding wall (25), the foreign matter can be blown away from the gap to the opposite side of the drain hole (29).

[0096] [Feature 15] The relief valve (10, 10B to 10E) according to any one of Features 1 to 14, wherein the valve hole (13, 13X) is wider than the discharge hole (92), and the entire discharge hole (92) is arranged to face a part of the valve hole (13, 13X).

[0097] In the relief valve (10, 10B to 10E) of feature 15, the valve hole (13, 13X) is wider than the discharge hole (92), so that an increase in fluid resistance due to the relief valve (10, 10B to 10E) is suppressed.

[0098] <Second Feature Group> [Feature 1] A relief valve (10-10E) comprising: a base portion (11) having a valve hole (13, 13X) and a valve seat sealing member (21) surrounding the valve hole (13, 13X); a valve body (35) having, at its outer edge, an annular abutment portion (35D) that moves back and forth while facing the valve hole (13, 13X) and moves toward and away from the valve seat sealing member (21); and an annular protrusion (18) that is provided at the inner edge of the base portion (11), with the valve seat sealing member (21) fitting onto the outside and the valve hole (13, 13X) on the inside, and wherein a tip surface of the annular protrusion (18) is located flush with the inner edge of the valve seat sealing member (21) or further ahead in the protruding direction of the annular protrusion (18).

[0099] In the relief valves (10 to 10E) of Feature 1, the tip surface of the annular protrusion (18) located between the valve seat seal member (21) and the valve hole (13, 13X) is flush with the inner edge of the valve seat seal member (21) or is located further forward in the protruding direction of the annular protrusion (18), so that the valve seat seal member (21) is not directly subjected to the dynamic pressure of the fluid discharged from the valve hole (13, 13X). This prevents the valve seat seal member (21) from being separated due to the dynamic pressure of the fluid.

[0100] [Feature 2] The relief valve (10 to 10E) according to Feature 1, further comprising: a fluid guide portion (35G) that is provided near an outer edge of the valve body (35), and that is inclined so as to gradually move away from the valve seat sealing member (21) in the penetrating direction of the valve hole (13, 13X) from the annular abutment portion (35D) toward the center of the valve hole (13, 13X).

[0101] According to the relief valves (10 to 10E) of feature 2, the dynamic pressure of the fluid guided by the fluid guide portion (35G) of the valve body (35) acts in a direction that deepens the fit of the valve seat seal member (21) with the annular protrusion (18), thereby suppressing separation of the valve seat seal member (21) due to the dynamic pressure of the fluid.

[0102] [Feature 3] The relief valve (10 to 10E) according to Feature 2, wherein the valve body (35) has a shape that bulges out on the side away from the valve hole (13, 13X) as a whole.

[0103] In the relief valves (10 to 10E) of feature 3, the valve element (35) is shaped to bulge on the side away from the valve hole (13, 13X), so that the dynamic pressure of the fluid can be easily received in the open state, and the valve element (35) can easily move to the valve opening side. This makes it possible to discharge a large amount of fluid at once immediately after the valve element (35) opens.

[0104] [Feature 4] The relief valve (10 to 10E) according to any one of Features 1 to 3, further comprising: a recess (20) formed in the base portion (11) at a mating surface with the valve seat seal member (21); and a fitting protrusion (23) provided on the valve seat seal member (21) and fitting into the recess (20).

[0105] According to the relief valves (10 to 10E) of feature 4, the fitting projection (23) of the valve seat sealing member (21) is fitted into the recess (20) of the base portion (11), thereby making it possible to make the valve seat sealing member (21) less likely to come off.

[0106] [Feature 5] The relief valve (10 to 10E) according to Feature 4, wherein a plurality of protrusions (23B) are provided on an inner surface of the recess (20) or a side surface of the fitting protrusion (23), and the fitting protrusion (23) is press-fitted into the recess (20).

[0107] According to the relief valve (10 to 10E) of feature 5, the valve seat seal member (21) can be made difficult to separate.

[0108] [Feature 6] The relief valve (10 to 10E) according to Feature 5, wherein the recess (20) extends circumferentially around the annular protrusion (18) or has a groove shape surrounding the annular protrusion, and the plurality of protrusions (23B) are formed on both side surfaces of the fitting protrusion (23) on the valve hole side and on the opposite side thereof.

[0109] The recess (20) and the fitting protrusion (23) may have a cross-sectional shape such as a circular, elliptical, or oval shape, or may be a groove-like shape extending along the circumferential direction of the annular protrusion (18) or surrounding the annular protrusion (18) as in Feature 6. In addition, in the configuration of Feature 6, by forming a plurality of protrusions (23B) on both side surfaces of the fitting protrusion (23) on the valve hole side and the opposite side, separation of the valve seat seal member (21) due to the dynamic pressure of the fluid is suppressed.

[0110] [Feature 7] The relief valve (10 to 10E) according to Feature 6, wherein the plurality of protrusions (23B) extend along a fitting direction with respect to the recess (20).

[0111] According to the relief valve (10 to 10E) of feature 7, the fitting protrusion (23) can be easily fitted into the recess (20).

[0112] [Feature 8] The relief valve (10 to 10E) according to Feature 7, wherein the plurality of protrusions (23B) are arranged offset from one another on both side surfaces of the fitting protrusion (23).

[0113] The plurality of protrusions (23B) may be provided, for example, on either one of the two side surfaces of the fitting protrusion (23), or on both side surfaces of the fitting protrusion (23). Furthermore, when the plurality of protrusions (23B) are provided on both side surfaces of the fitting protrusion (23), the plurality of protrusions (23B) may be arranged opposite each other at the same position on both sides, or may be arranged in a staggered pattern as in Feature 8. According to the configuration of Feature 8, the fitting protrusion (23) can be deformed in a slight meandering shape to fit within the recess (20).

[0114] <Third Feature Group> [Feature 1] A valve disc (35) is provided with a base portion (11) that is placed on an opening edge of a discharge hole (92) of a container (90) and that includes a valve hole (13, 13X) that faces the discharge hole (92) and a valve seat (11Z) that surrounds the valve hole (13, 13X), a valve disc (35) that is disposed opposite the valve hole (13, 13X) and has an annular abutment portion (35D) that abuts against the valve seat (11Z), a shaft (40) that is provided on one of the valve disc (35) and the base portion (11), and a shaft fitting portion (31) that is provided on the other of the valve disc (35) and the base portion (11) and that fits onto the outside of the shaft (40), so that the valve disc (35) can be moved linearly in the axial direction of the shaft (40). and a seal member (21) that is provided on one of the valve seat (11Z) or the annular contact portion (35D) and that is in close contact with the other as a seal contact portion (35D), the relief valve (10, 10B to 10D) is provided with a clearance (C1, C2, C3) in the slide support mechanism (40K) that allows the shaft (40) to be inclined relative to the shaft fitting portion (31) and to be in a partial contact state in which only a portion of the circumferential direction of the seal contact portion (35D) is in contact with the seal member (21).

[0115] In the relief valve (10, 10B to 10D) of feature 1, a slide support mechanism (40K) that supports the valve body (35) so that it can move linearly is provided with clearances (C1, C2, C3) that allow a partial abutment state in which only a portion of the circumferential seal contact portion (35D) abuts against the seal member (21). As a result, when the relief valve (10, 10B to 10D) is opened from a state in which the entire periphery of the seal contact portion (35D) is attached to the seal member (21) after being maintained in a closed state for a long period of time, the valve body (35) tilts and the seal contact portion (35D) gradually separates from the seal member (21), thereby reducing resistance when the valve is opened and stabilizing the valve opening operation.

[0116] [Feature 2] The relief valve (10C) according to Feature 1, wherein the shaft (40) is disposed at a position offset from a centroid (P1) of an area surrounded by the valve seat (11Z) when viewed in the axial direction.

[0117] According to the configuration of feature 2, the valve body (35) is inclined relative to the linear movement direction when subjected to pressure in the container (90), thereby reducing resistance when the valve is opened.

[0118] [Feature 3] The relief valve (10D) according to Feature 1, wherein a centroid (P1) of an area surrounded by the valve seat (11Z) and a centroid (P3) of the valve hole (13X) are misaligned when viewed in the axial direction of the shaft (40).

[0119] According to the configuration of feature 3, when the pressure inside the container (90) suddenly increases, the dynamic pressure of the fluid flowing through the container (90) acts unevenly on the valve body (35), causing the valve body (35) to tilt, thereby reducing resistance when the valve is opened.

[0120] [Feature 4] The relief valve (10, 10B to 10E) according to any one of Features 1 to 3, wherein the surface roughness of the seal contact portion (35D) varies so as to be unbalanced in the circumferential direction.

[0121] In the relief valve (10, 10B to 10E) of feature 4, the surface roughness of the seal contact portion (35D) varies so as to be unbalanced in the circumferential direction, so that the seal contact portion (35D) gradually separates from the seal member (21) starting from the portion with the rougher surface roughness, thereby reducing resistance when the valve is opened.

[0122] [Feature 5] The relief valve (10, 10B to 10E) according to any one of Features 1 to 4, wherein the seal contact portion (35D) has a shape that protrudes toward the seal member (21), and the base end side of the contact area (S2) with the seal member (21) of the seal contact portion (35D) has a surface roughness that is greater on the base end side than on the tip end side.

[0123] In the relief valve (10, 10B to 10E) of feature 5, the base end side of the contact area (S2) with the seal member (21) at the seal contact portion (35D) has a larger surface roughness than the tip end side, so resistance when the valve is opened is reduced compared to a contact area (S2) with the seal member (21) having the same surface roughness and in the same close contact with the seal member (21).

[0124] [Feature 6] The relief valve (10 to 10D) according to Feature 5, wherein the base end side of the contact area (S2) has a textured surface.

[0125] The difference in surface roughness between the base end side and the tip end side in the contact region (S2) described above may be achieved by mirror finishing only the tip end side, or by making the base end side a textured surface as in Feature 6, or by other structures.

[0126] [Feature 7] A base portion (11) is placed on the opening edge of a discharge hole (92) of a container (90) and includes a valve hole (13, 13X) facing the discharge hole (92) and a valve seat (11Z) surrounding the valve hole (13, 13X); a valve element (35) having an annular abutment portion (35D) that approaches and moves away from the valve seat (11Z); a slide support mechanism (40K) that supports the valve element (35) so as to be linearly movable relative to the base portion (11); a sealing member (21) provided on one side of the annular contact portion (35D) or the annular contact portion (35B), and the other side being in close contact as a sealing contact portion (35D), the slide support mechanism (40K) allows the valve body (35) to tilt so that only a portion of the circumferential direction of the sealing contact portion (35D) is in partial contact with the sealing member (21).

[0127] In the relief valve (10, 10B to 10E) of feature 7, a slide support mechanism (40K) that supports the valve element (35) so that it can move linearly allows the valve element (35) to tilt so that only a portion of the circumferential seal contact portion (35D) is in partial contact with the seal member (21). As a result, when the relief valve (10, 10B to 10D) is opened from a state in which the entire periphery of the seal contact portion (35D) is attached to the seal member (21) after being maintained in a closed state for a long period of time, the valve element (35) tilts and the seal contact portion (35D) gradually separates from the seal member (21), thereby reducing resistance when the valve is opened and stabilizing the valve opening operation.

[0128] Although the present specification and drawings disclose specific examples of the technology included in the scope of the claims, the technology described in the claims is not limited to these specific examples, but also includes various modifications and variations of the specific examples, and also includes parts of the specific examples taken out alone.

[0129] 10, 10B to 10D Relief valve 11 Base portion 11Z Valve seat 13, 13X Valve hole 14 Mounting hole 14N Female thread portion 15 Nut 17 Annular seal member 18 Annular protrusion 19 Seal member mounting portion 20 Groove portion 21 Valve seat seal member (seal member) 23 Fitting protrusion 23B Protrusion 25 Valve body surrounding wall 26 First wall portion 27 Second wall portion 31 Shaft fitting portion 35 Valve body 35D Annular abutment portion (seal contact portion) 35F Flange portion 35G Fluid guide portion 35K Obtuse angled corner portion 40 Shaft 40H Hinge portion 40K Slide support mechanism 45 Side guide portion 45A Vertical surface 45B Inclined surface 90 Container 92 Discharge hole 93 Mounting hole B Bolt C1, C2, C3 Clearance S1 Installation space S2 Contact area

Claims

1. A base portion that is overlaid on the opening edge of the discharge hole of the container and includes a valve hole facing the discharge hole and a valve seat surrounding the valve hole; A valve body having an annular contact portion that contacts the valve seat; A slide support mechanism including a shaft provided on one of the valve body and the base portion and a shaft fitting portion provided on the other and fitted outside the shaft, and supporting the valve body so as to be linearly movable in the axial direction of the shaft; A seal member provided on one of the valve seat or the annular contact portion, with the other being in close contact as a seal contact portion; In a relief valve having: The relief valve, wherein the slide support mechanism is provided with a clearance that allows the shaft to be relatively inclined with respect to the shaft fitting portion so that only a part of the circumferential direction of the seal contact portion comes into contact with the seal member, resulting in a partial contact state.

2. The relief valve according to Claim 1, wherein the shaft is arranged offset from the centroid of the region surrounded by the valve seat when viewed in the axial direction.

3. The relief valve according to Claim 1, wherein, when viewed in the axial direction of the shaft, the centroid of the region surrounded by the valve seat and the centroid of the valve hole are offset.

4. The relief valve according to any one of Claims 1 to 3, wherein the surface roughness of the seal contact portion is uneven in the circumferential direction.

5. The seal contact portion has a shape protruding toward the seal member, The relief valve according to any one of Claims 1 to 3, wherein the base end side of the contact region of the seal contact portion with the seal member has a larger surface roughness than the tip side.

6. The relief valve according to Claim 5, wherein the base end side of the contact region is a knurled surface.