check valve

Abstract

A check valve (1) includes a movable body (30), a valve housing (10), a valve cylinder (14), a primary flow path (40), and a secondary flow path (50). The movable body (30) is a component capable of linearly reciprocating between a closed state (closed to a valve seat (12)) and an open state (separated from the valve seat (12)). The valve housing (10) is a component containing the valve cylinder (14). The valve seat (12) is fixed in the valve housing (10). The valve cylinder (14) is a component extending in the direction of movement of the movable body (30) and is a component for the movable body (30) to move within it. The primary flow path (40) is located upstream of the valve cylinder (14) with its main axis as its axis. The secondary flow path (50) is located downstream of the valve cylinder (14) with its main axis as its axis. The first mainstream of the fluid flowing from the upstream side to the downstream side through the interior of the valve tube (14) has a component that is more present in the direction of movement of the moving body (30) than in the direction of the main axis.

Description

Technical Field

[0001] This invention relates to check valves. Background Technology

[0002] A check valve is known for directing fluid through a piping system in one direction.

[0003] Regarding this technology, Patent Document 1 discloses a straight pipe joint type check valve in which the upstream primary flow path (inflow path) and the downstream secondary flow path (outflow path) are arranged coaxially. This check valve is referred to as a tilting type in which the valve core moves obliquely relative to the main axis direction of the primary and secondary flow paths. More specifically, the check valve of Patent Document 1 includes: a valve box (12) having a valve seat (15); a housing (23) capable of sitting on the valve seat (15); and a helical spring (18) having a force in the direction of pressing down the valve core (16).

[0004] Fluid pushes the valve core (16) upward, flowing from the primary flow path to the secondary flow path. During the flow of fluid from the primary flow path to the secondary flow path, the upward push of the valve core is maintained by the flow of this fluid.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: US Patent No. 1703248 Summary of the Invention

[0008] The problem the invention aims to solve

[0009] However, during the upward pushing of the valve core, the primary flow path connects to the secondary flow path, thus creating a tendency for fluid to move from the primary flow path towards the secondary flow path along the main axis. Therefore, the upward-pushed valve core is positioned away from the flow path through which the fluid moves, making it less susceptible to water pressure. Consequently, after the valve core is pushed upward, it becomes difficult to maintain this upward-pushed state.

[0010] The present invention was made in view of the problems mentioned above, and provides a check valve that is easy to maintain the valve core in an upwardly pushed state.

[0011] Solution for solving the problem

[0012] The check valve of the present invention is characterized in that it is a straight-pipe type inclined-rise check valve for allowing fluid to flow internally from an upstream side to a downstream side, wherein the check valve includes: a valve seat; a movable body capable of linearly reciprocating to a closed state in close contact with the valve seat and an open state separated from the valve seat; a valve box containing a valve cylinder extending in the movement direction of the movable body and for the movable body to move internally, the valve seat being fixed to the valve box; a primary flow path located upstream of the valve cylinder, with the main axis direction of the straight line as its axis; and a secondary flow path located downstream of the valve cylinder, with the main axis direction as its axis, the first mainstream flow direction of the fluid flowing from the upstream side to the downstream side through the interior of the valve cylinder having a component in the movement direction of the movable body that is more abundant than the component in the main axis direction.

[0013] The main flow of fluid inside the valve cylinder, i.e., the first main flow, is directed towards the direction of movement of the moving body, which has a greater component than that in the main axis direction. Thus, the first main flow mainly pushes the valve core in the direction of movement (especially towards the top side of the direction of movement).

[0014] The effects of the invention

[0015] According to the check valve of the present invention, the first main flow flows primarily in the direction that pushes the valve core in the direction of movement, thereby causing the fluid to continuously collide with the valve core in the direction of pushing the valve core upward.

[0016] Therefore, it is easy to maintain the valve core in the upward-pushing state. Attached Figure Description

[0017] The above-described objectives, as well as other objectives, features, and advantages, will become even clearer through the preferred embodiments described below and the accompanying drawings attached thereto.

[0018] Figure 1 This is a perspective view showing an example of a check valve according to the first embodiment of the present invention.

[0019] Figure 2 This is a longitudinal sectional view along the main axis of the check valve in the closed state according to the first embodiment.

[0020] Figure 3 This is a longitudinal sectional view along the main axis of the check valve in the open state according to the first embodiment.

[0021] Figure 4 (a) is a velocity distribution diagram of fluid flow in the check valve of the first embodiment. Figure 4 (b) is in relation to Figure 4 (a) is the same as the diagram representing regions A to D.

[0022] Figure 5 (a) and Figure 5 (b) is a velocity distribution diagram of fluid flow in the check valve of the first embodiment.

[0023] Figure 6 This is a rear view of the valve box of the check valve according to the first embodiment. The outline of the valve shaft is shown in dashed lines.

[0024] Figure 7 (a) is a diagram obtained by viewing the lower end of the first embodiment from the rear. Figure 7 (b) is a diagram obtained by viewing the lower end of the valve shaft of the first embodiment from the rear.

[0025] Figure 8 (a) is a diagram obtained by partially decomposing the valve core of the first embodiment from the rear. Figure 8 (b) is a longitudinal sectional view of the valve core and valve shaft.

[0026] Figure 9 This is a perspective view of the check valve according to the second embodiment of the present invention.

[0027] Figure 10 This is a longitudinal sectional view along the main axis of the check valve in the closed state according to the second embodiment.

[0028] Figure 11 This is a longitudinal sectional view along the main axis of the check valve in the open state according to the second embodiment.

[0029] Figure 12 This is a velocity distribution diagram of fluid flow in the check valve of the second embodiment.

[0030] Figure 13 (a) and Figure 13 (b) is a velocity distribution diagram of fluid flow in the check valve of the second embodiment.

[0031] Figure 14 This is a rear view of the valve box of the check valve according to the second embodiment. The outline of the valve shaft is shown in dashed lines. Detailed Implementation

[0032] The various components of the check valve of the present invention do not need to exist independently. Multiple components are allowed to be formed as a single component, a single component is formed by multiple components, a component is part of other components, or a part of a component is repeated by a part of other components.

[0033] Hereinafter, embodiments of the present invention will be described based on the accompanying drawings. Furthermore, in the drawings, common reference numerals are used to label corresponding constituent elements, and repetitive descriptions are omitted where appropriate.

[0034] Furthermore, in the present embodiment, the description is given by defining the front-rear, left-right, up-down directions as shown in the drawings. In the present embodiment, the front-rear direction coincides with the main shaft direction described later. In addition, the left-right direction may be referred to as the width direction of the check valve 1. However, this is defined for convenience to simply describe the relative relationship between constituent elements, and does not limit the direction during manufacture or use of the product implementing the present invention. In addition, the up-down direction is not limited to the vertical direction, but represents a direction orthogonal to the main shaft direction and the width direction. For example, when the check valve 1 is placed on a horizontal plane and installed on a pipe, the up-down direction is the vertical direction, but when the check valve 1 is installed on a surface inclined with respect to the horizontal plane or an upright surface perpendicular to the horizontal plane, the up-down direction is not the vertical direction.

[0035] In addition, the plane described in the present invention represents a shape physically formed with a plane as the target, and of course does not need to be a geometrically complete plane.

[0036] <First Embodiment>

[0037] (Check Valve)

[0038] Figure 1 is a perspective view showing an example of the check valve 1 according to the first embodiment of the present invention. Figure 2 is a longitudinal sectional view of the check valve 1.

[0039] First, an outline of the check valve 1 of the present embodiment will be described.

[0040] As Figure 2 illustrated, the check valve 1 is a straight joint type inclined lift type (Japanese: 斜めリフト型) check valve in which a fluid 200 (see Figure 4 ) flows from the upstream side to the downstream side inside the check valve.

[0041] The check valve 1 comprises a valve seat 12, a moving body 30, a valve box 10, a primary flow path 40, and a secondary flow path 50.

[0042] The moving body 30 is a member that can linearly reciprocate between a closed state in close contact with the valve seat 12 and an open state separated from the valve seat 12. The valve box 10 is a member including a valve cylinder 14. The valve seat 12 is fixed to the valve box 10. The valve cylinder 14 is a member extending in the moving direction of the moving body 30, and is a member for allowing the moving body 30 to move inside thereof.

[0043] The primary flow path 40 is located upstream of the valve cylinder 14, and takes a linear main shaft direction ( Figure 2 the direction indicated by the dash-dotted line I therein) as the axis center. The secondary flow path 50 is located downstream of the valve cylinder 14, and takes the main shaft direction as the axis center.

[0044] As Figure 4(a) and Figure 4 As illustrated in (b), the first main flow of fluid 200 from the upstream side through the interior of valve cylinder 14 towards the downstream side ( Figure 4 The flow direction of the fluid 200 (as shown in region A or region B of (b)) has a component in the direction of movement of the moving body 30 that is greater than that in the direction of the main axis. By utilizing the combination of the shapes and configurations of the various elements constituting the check valve 1, it is possible to achieve a first main flow in which the component in the direction of movement of the moving body 30 is greater than that in the direction of the main axis. The method of achieving this is described in detail below.

[0045] The main flow of the fluid 200 inside the valve cylinder 14, i.e., the first main flow, has a component that is more concentrated in the direction of movement of the moving body 30 than in the direction of the main axis. Therefore, the first main flow primarily pushes the moving body 30 (valve core 32, described later) upwards in the direction of movement (especially towards the top side of the direction of movement). Because the first main flow primarily pushes the valve core 32 upwards in the direction of movement, the fluid 200 continuously collides with the valve core 32 in this upward-pushing direction. This facilitates maintaining the upward-pushing state of the valve core 32.

[0046] Next, the check valve 1 of this embodiment will be described in detail.

[0047] Check valve 1 is a component installed midway in a pipe that allows fluid to flow from upstream to downstream in one direction, and is used to suppress backflow of fluid from downstream to upstream. As described above, the check valve 1 in this embodiment is a straight-pipe connector type with a ramp. The straight-pipe connector type check valve 1 is a check valve in which the pipe connected to the downstream side of check valve 1 (downstream side pipe) extends along the extension line of the pipe connected to the upstream side of check valve 1 (upstream side pipe). That is, in the straight-pipe connector type check valve, the outflow direction is on the extension line of the inflow direction. In this embodiment, check valve 1 connects the upstream side pipe and the downstream side pipe in such a way that the upstream side pipe and the downstream side pipe are arranged coaxially. Furthermore, the ramp-type check valve 1 is a check valve in which the valve core moves in a direction inclined relative to the main axis direction described later.

[0048] like Figure 2 As illustrated, the closed state of check valve 1 is a state in which the movement of fluid from upstream to downstream of check valve 1 is restricted by the movable body 30 (described later). In the closed state, it is not necessary to completely prevent the movement of fluid 200; it is sufficient to adequately restrict the movement of fluid 200 according to the desired effect. In the closed state of this embodiment, as described later, the movable body 30 rests on the valve seat 12, thereby narrowing the flow path of fluid 200 due to the movable body 30, thus restricting the movement of fluid 200. Figure 3As illustrated, the open state of check valve 1 is a state that does not restrict the movement of fluid 200 compared to the closed state of check valve 1. Specifically, in the open state of check valve 1, valve seat 12 is separated from moving body 30, creating a gap between valve seat 12 and moving body 30. Fluid 200 can move from upstream to downstream through this gap. In the open state, moving body 30 can be pushed up to its highest position or located midway along valve shaft 34. That is, in the open state of check valve 1, some movement of fluid 200 from upstream to downstream can be restricted. However, the restriction on the movement of fluid 200 in the open state of check valve 1 is less than the restriction on the movement of fluid 200 in the closed state of check valve 1.

[0049] Figure 2 This is a longitudinal sectional view of check valve 1.

[0050] Valve housing 10 is a casing in which fluid flows. Valve housing 10 houses movable body 30. The casing is formed by wall portion 19. Here, wall portion 19 includes piping wall portion 19a, valve cylinder wall portion 19b, and top 15, which will be described later.

[0051] In this embodiment, the valve box 10 includes a piping section 11 and a valve cylinder 14. The piping section 11 is the part where the fluid 200 mainly flows from upstream to downstream. That is, the piping section 11 is the part that connects the fluid inflow path (primary flow path 40) and the outflow path (secondary flow path 50). More specifically, the piping section 11 is positioned in the direction that connects the center of the inlet 11a and the center of the outlet 11b of the check valve 1. Figure 2 Extend along the left-right direction (in the direction indicated by the dashed line). Here, the axis connecting the center of the inlet 11a and the center of the outlet 11b (in the direction indicated by the dashed line) is... Figure 2 The axis shown by the single-dotted line is called the main axis, and the direction of extension of the main axis is called the main axis direction. The piping section 11 is formed by a wall section 19 (piping wall section 19a) arranged in such a way that it covers the area around the main axis with the main axis as the axis center.

[0052] At both ends of the piping section 11 in the main axis direction, there are flanges 17 protruding in a direction orthogonal to the main axis direction.

[0053] Valve cylinder 14 is a part of valve box 10, specifically the part that houses the movable body 30. The valve cylinder 14 is positioned in the direction of movement of the movable body 30 (...). Figure 2 It extends in the inclined direction connecting the upper left and lower right of the valve shaft. The valve cylinder 14 is formed by a wall portion 19 (valve cylinder wall portion 19b) arranged to cover the shaft with the moving direction of the moving body 30 as the axis center. More specifically, the valve cylinder 14 is formed by a valve cylinder wall portion 19b arranged to cover the periphery of the valve shaft.

[0054] At the upper end of the valve cylinder 14, the internal space of the valve cylinder 14 is enclosed by the top 15. The upper end of the valve cylinder 14 is one end on the upper side in the direction of movement of the valve cylinder 14. Furthermore, this upper side is the side in which the valve cylinder is located in the valve box 10 with the main shaft as a reference. This upper side is also referred to as the top surface side.

[0055] At the lower end of the valve cylinder 14, the internal space of the valve cylinder 14 communicates with the internal space of the piping section 11. The lower end of the valve cylinder 14 is one end on the lower side in the direction of movement of the valve cylinder 14. The lower side is also referred to as the bottom surface side.

[0056] In this embodiment, the top 15 also serves as the cover of the valve cylinder 14. That is, by opening the top 15, the internal space of the valve cylinder 14 can communicate with the outside. The top 15 is fixed to the valve cylinder wall 19b in a manner that prevents it from being opened by fasteners 15b.

[0057] The valve seat 12 is a portion fixed to the valve housing 10 within the check valve 1, and is the portion that contacts the moving body 30 when the check valve 1 is closed. In this embodiment, the valve seat 12 is a protrusion that extends from the wall portion 19 (pipe wall portion 19a or valve cylinder wall portion 19b) toward the interior of the valve housing 10. More specifically, the valve seat 12 protrudes radially inward from the wall portion 19 toward the valve cylinder 14. The radial direction of the valve cylinder 14 is the direction that radiates from the valve shaft 34 (described later) toward the periphery of the valve cylinder 14 (valve cylinder wall portion 19b) when viewed from the moving direction of the moving body 30. The radial inward direction of the valve cylinder 14 is the direction that extends from the periphery of the valve cylinder 14 (valve cylinder wall portion 19b) toward the valve shaft 34 when viewed from the moving direction of the moving body 30. The valve seat 12 is a component distinct from the valve housing 10 (wall portion 19), and can be fixed to the valve housing 10 by bonding, welding, or other methods, or it can be integrally formed within the valve housing 10.

[0058] In this embodiment, the valve seat 12 extends around the valve shaft 34. In other words, the valve seat 12 extends circumferentially around the piping section 11. As a result, the valve seat 12 can make integral contact with the periphery of the moving part (especially the sealing part 36) described later.

[0059] In this embodiment, the valve seat 12 has an upper surface facing the moving body 30 in the moving direction. The moving body 30 can make surface contact with this surface.

[0060] The movable body 30 is a component that can move in a predetermined direction of movement. When the movable body 30 moves downward in the direction of movement, it can contact the valve seat 12, and when it moves upward in the direction of movement, it can separate from the valve seat 12.

[0061] The movable body 30 has a sufficient diameter to restrict the movement of fluid 200 from upstream to downstream. In this embodiment, the diameter of the movable body 30 (the maximum diameter of the movable body 30 when viewed from the direction of movement) is larger than the inner diameter of the valve seat 12 (the maximum diameter of the movable body 30 when viewed from the direction of movement). Therefore, when the check valve 1 is closed and the movable body 30 contacts the valve seat 12, the movable body 30 can contact the valve seat 12 around its entire circumference, thus sufficiently restricting the movement of fluid 200. Alternatively, the diameter of the movable body 30 may be the same as or smaller than the inner diameter of the valve seat 12.

[0062] like Figure 2 As illustrated, in this embodiment, the movable body 30 includes a valve core 32 and a valve shaft 34.

[0063] The valve core 32 is a component supported on the valve seat 12 in the closed state of the check valve 1. The valve core 32 being supported on the valve seat 12 means that the valve core 32 is placed on the valve seat 12, and at least a portion of the weight of the valve core 32 is applied to the valve seat 12. The valve core 32 moves in the direction of movement of the moving body 30, thereby changing the check valve 1 from a closed state to an open state, or from an open state to a closed state.

[0064] The valve shaft 34 is a component used to assist the movement of the valve core 32. Specifically, in this embodiment, the valve core 32 is fixed to the valve shaft 34, and as described later, at least one end of the valve shaft 34 is inserted into the cylindrical portion 16. Therefore, the valve shaft 34 moves or slides along the cylindrical portion 16, thereby enabling the valve core 32 to move in a predetermined direction of movement. Alternatively, in this embodiment, the valve core 32 may not be fixed to the valve shaft 34, but may slide on the valve shaft 34, thereby allowing the valve shaft 34 to assist the movement of the valve core 32.

[0065] In this embodiment, the valve shaft 34 is a component extending from the valve core 32 in two directions in the moving direction. The valve shaft 34 extending from the valve core 32 in two directions in the moving direction is sufficient for the valve shaft 34 to extend in at least one of the following states: the check valve 1 is in a closed state, an open state, and a state transitioning from a closed state to an open state. In this embodiment, the valve core 32 is fixed to the valve shaft 34, and the positional relationship between the valve core 32 and the valve shaft 34 is fixed. The valve core 32 is positioned midway along the length of the valve shaft 34. That is, in one of the following states: the check valve 1 is in a closed state, an open state, and a state transitioning from a closed state to an open state, the valve shaft 34 extends in two directions in the moving direction from the valve core 32. Alternatively, in an embodiment where the valve core 32 is not fixed to the valve shaft 34, the valve shaft 34 may extend in two directions in the moving direction at least when the check valve 1 is transitioning from a closed state to an open state. In the closed or open state of check valve 1, valve shaft 34 can extend from valve core 32 in two directions in the moving direction, or it can extend from valve core 32 in only one direction in the moving direction.

[0066] In this embodiment, the valve shaft 34 is a shaft member disposed at the center of the valve cylinder 14 in the moving direction of the moving body 30 (valve core 32), and is a member that passes through the valve core 32, but is not limited thereto. The valve shaft 34 may also be a cylindrical member disposed at a position radially outward of the valve cylinder 14 than the valve core 32. The valve core 32 may also move or slide along the valve shaft 34 inside the valve shaft 34.

[0067] In this embodiment, as described above, the valve core 32 is fixed to the valve shaft 34. Specifically, as... Figure 8 As shown in (b), the valve core 32 is fixed to the valve shaft 34 by a screw 35. The valve shaft 34 has a protrusion, namely a screw receiving portion 34d, that protrudes from the circumferential surface of the valve shaft 34. Parts of the valve core 32 (the first holding portion 38 and the second holding portion 39, described later) are disposed between the screw 35 and the screw receiving portion 34d. The screw 35 is screwed into a screw groove provided on the circumferential surface of the valve shaft 34 and is close to the screw receiving portion 34d, so that the screw receiving portion 34d and the screw 35 can hold the valve core 32.

[0068] like Figure 2 As illustrated, the top 15 includes a top cavity 15a capable of receiving a portion (upper end 34b) of the valve shaft 34. In this embodiment, the portion of the top 15 protrudes upward in the moving direction of the moving body 30, and the interior of this portion is a cavity.

[0069] The upper end portion 34b can be housed in the top cavity 15a, so that the valve shaft 34 can be positioned sufficiently high in the direction of movement of the moving body 30 when in the open state.

[0070] In this embodiment, the two ends (upper end 34b and lower end 34a) of the valve shaft 34 are supported on the wall 19 of the valve housing 10. In this embodiment, the upper end 34b of the valve shaft 34 is supported on the top 15, and the lower end 34a of the valve shaft 34 is supported on the piping wall 19a or the valve cylinder wall 19b. The two ends of the valve shaft 34 being supported on the wall 19 of the valve housing 10 means that each end of the valve shaft 34 is in contact with the valve housing 10 or a component fixed to the valve housing 10, and at least a portion of the weight of the valve shaft 34 at each end is applied to the valve housing 10. Alternatively, the valve shaft 34 may contact the wall 19 of the valve housing 10, with its weight directly applied to the wall 19, or the valve shaft 34 may contact other components fixed to the wall 19 of the valve housing 10, with its weight indirectly applied to the wall 19 via these other components.

[0071] In this embodiment, the weight of the valve shaft 34 is also supported by the spring body 37, which will be described later. Specifically, the valve shaft 34 is disposed between the upper end cylinder 16b fixed to the top 15 and the valve core 32. Furthermore, as described later, the spring body 37 applies force to the top 15 and the valve core 32 respectively in the moving direction of the moving body 30. The spring body 37 applies force to the top 15 and the valve core 32 respectively, thereby keeping the valve shaft 34, spanning the upper end cylinder 16b and the valve core 32, in the same direction as the moving body 30.

[0072] Specifically, the lower end 34a (the end of the valve shaft 34 on the bottom side of the check valve 1) and the upper end 34b (the end of the valve shaft 34 on the top side of the check valve 1) are respectively inserted into the cylindrical portion 16 (lower end cylindrical portion 16a and upper end cylindrical portion 16b) fixed in the valve box 10.

[0073] The lower end sleeve 16a, into which the lower end 34a is inserted, is fixed to the wall 19 (pipeline wall 19a or valve sleeve wall 19b) of the valve box 10. Specifically, as Figure 6 As illustrated, the lower end 34a of the valve shaft 34 is supported by support portions 18 (first support portion 18a and second support portion 18b). In this embodiment, the support portion 18 protrudes from the wall portion 19 (piping wall portion 19a or valve cylinder wall portion 19b) of the valve housing 10 and extends toward the lower end 34a. More specifically, as shown... Figure 6 As shown in the diagram, each support portion 18 extends toward the ring portion 18c at the center of the piping portion 11. The ring portion 18c and each support portion 18 are integrally formed. Additionally, the lower end cylindrical portion 16a (see reference...) Figure 2 The portion of the lower end 34a is partially inserted into the ring portion 18c and connected to the ring portion 18c. In this embodiment, the lower end 34a is supported by two or more (four) support portions 18. The four support portions 18 are arranged in a plus sign (+) shape. In addition, as Figure 2As illustrated, in this embodiment, the second support portion 18b protrudes from the top of the protrusion 11e (described later) or the top of the second protrusion 11f.

[0074] Moreover, such as Figure 2 As illustrated, the upper cylindrical portion 16b, into which the upper end portion 34b is inserted, is fixed to the top 15. More specifically, the upper cylindrical portion 16b is fixed to the top 15 in such a way that its interior communicates with the top cavity portion 15a. The interior space of the upper cylindrical portion 16b is aligned with the top cavity portion 15a in the moving direction of the moving body 30. In this embodiment, the upper cylindrical portion 16b is fitted and fixed to the top 15.

[0075] When the check valve 1 changes from the open state to the closed state, or when the check valve 1 changes from the closed state to the open state, the valve shaft 34 slides on the inner walls of the lower end cylinder 16a and the upper end cylinder 16b.

[0076] like Figure 2 As illustrated, in the closed state of check valve 1, the upper end 34b of valve shaft 34 is inserted into the upper cylinder 16b (particularly its lower end), and the lower end 34a of valve shaft 34 penetrates the lower cylinder 16a and the ring portion 18c. At this time, the lower end 34a of valve shaft 34 is close to the pipe wall 19a. In this embodiment, the separation distance between the lower end 34a and the pipe wall 19a (the distance between the lower end 34a and the pipe wall 19a in the moving direction of the moving body 30) is smaller than the insertion depth of the upper end 34b into the upper cylinder 16b (the partial length of the upper end 34b inserted into the upper cylinder 16b and the length in the moving direction of the moving body 30). In the closed state of check valve 1, valve shaft 34 extends downward to a degree extremely close to the pipe wall 19a, so that in the open state of check valve 1, valve shaft 34 can be inserted into the lower cylinder 16a with sufficient insertion depth. On the other hand, when the check valve 1 is closed, the insertion depth of the valve shaft 34 into the upper end cylinder 16b is large enough so that the valve shaft 34 is adequately supported by the upper end cylinder 16b in the closed state.

[0077] On the other hand, such as Figure 3 As illustrated, in the open state of check valve 1, the upper end portion 34b of valve shaft 34 extends through the upper end cylinder 16b. Furthermore, a portion of the upper end portion 34b protruding upwards from the upper end cylinder 16b is disposed within the top cavity 15a. On the other hand, the lower end portion 34a of valve shaft 34 is inserted into the lower end cylinder 16a (partially its upper end). Preferably, the insertion depth of the lower end portion 34a of valve shaft 34 in the open state into the lower end cylinder 16a (the length of the portion of the lower end portion 34a inserted into the lower end cylinder 16a, and the length in the moving direction of the moving body 30) is greater than that in the closed state of check valve 1 (see reference...). Figure 2The lower end 34a of the valve shaft 34 is separated from the pipe wall 19a by a large distance. As a result, the lower end 34a of the valve shaft 34 is adequately supported by the lower end cylinder 16a.

[0078] like Figure 8 As illustrated in (b), the valve core 32 of this embodiment includes a sealing portion 36, a first holding portion 38, and a second holding portion 39. Figure 2 As shown in the figure, the sealing part 36 is a component that is tightly attached to the valve seat 12 in the closed state. The first holding part 38 is a component disposed on the top surface side of the valve cylinder 14 of the sealing part 36. The second holding part 39 is a component disposed on the bottom surface side of the check valve 1 of the sealing part 36. The sealing part 36 is sandwiched between the first holding part 38 and the second holding part 39 in the movement direction. That is, the valve core 32 of this embodiment is formed by the second holding part 39, the sealing part 36 and the first holding part 38 being stacked sequentially from bottom to top.

[0079] In this embodiment, the sealing portion 36 is a gasket formed of resin. On the other hand, the first gripping portion 38 and the second gripping portion 39 are formed of metal.

[0080] In this embodiment, the central portion of the second gripping portion 39 has a recess 39a formed by an upward indentation in the moving direction of the moving body 30. Similarly, the central portion of the first gripping portion 38 has a recess 38a formed by an upward indentation in the moving direction of the moving body 30. Figure 2 As shown in the diagram, with the check valve 1 closed, it is possible to open the recesses 38a and 39a (refer to...). Figure 8 (b)) at least a portion of the lower end cylindrical portion 16a is internally housed.

[0081] like Figure 8 As illustrated in (b), in this embodiment, the wall portion of the dividing recess 39a is separated from the valve shaft 34 in the radial direction of the valve cylinder 14. That is, a lower end hollow portion 39b, which serves as a hollow portion, is disposed between the valve shaft 34 and the second grip portion 39 in the radial direction of the valve cylinder 14. In addition, the wall portion of the first grip portion 38 of the dividing recess 38a is separated from the wall portion of the second grip portion 39 of the dividing recess 39a, and a valve core inner hollow portion 38b, which serves as a hollow portion, is disposed between the first grip portion 38 and the second grip portion 39 in the radial direction of the valve cylinder 14.

[0082] A lower hollow portion 39b with a downward opening is formed in the lower part of the valve core 32, so that a portion of the fluid 200 flowing in from upstream may be retained inside or near the lower hollow portion 39b. Therefore, it is easy to maintain the valve opening when the check valve 1 is in the open state.

[0083] like Figure 2As illustrated, in this embodiment, the surface of the valve core 32 facing upstream (the lower surface 39d of the valve core 32, and the lower surface of the second gripping portion 39 facing the moving body 30 in the direction of movement) is a convex surface with a shape that protrudes towards the upstream side. In this embodiment, the radius of curvature of the lower surface 39d is relatively large. Specifically, when viewed from the width direction (left-right direction) of the check valve 1, the extension direction of the upstream portion of the lower surface 39d (the portion of the lower surface 39d from the center to the upstream end of the lower surface 39d) has a principal axis component and a radial component of the valve cylinder 14, and the radial component is larger than the principal axis component. The extension direction of the upstream portion of the lower surface 39d when viewed from the left-right direction can be set as the extension direction of the line connecting the center of the lower surface 39d and the upstream end of the lower surface 39d when viewed from the left-right direction. The lower surface 39d of the valve core 32 is a convex surface, so that, compared with the case where the lower surface 39d is a plane along the radial direction of the valve cylinder 14, as will be described later, even when the first mainstream flows in the direction of movement of the moving body 30, the flow direction of the first mainstream can be changed with less pressure loss.

[0084] In addition, in this embodiment, such as Figure 8 As illustrated in (a), the second gripping portion 39 is formed by including a hollow portion 39c. Specifically, a plurality of hollow portions 39c are arranged in a manner that surrounds the valve shaft 34. The hollow portions 39c are separated from each other by a separator extending in the moving direction of the moving body 30. With the help of this separator, the shape of the valve core 32 is easily maintained even when the valve core 32 is repeatedly pressed against the valve seat 12.

[0085] Alternatively, instead of this embodiment, a hollow portion 39c extending circumferentially from the valve cylinder 14 may be disposed inside the second gripping portion 39.

[0086] like Figure 2 and Figure 3 As illustrated, the movable body 30 of this embodiment includes a spring body 37. Specifically, the spring body 37 is a helical spring with the moving direction of the movable body 30 as its axis. The spring body 37 is disposed between the top 15 and the valve core 32 in the moving direction of the movable body 30, and applies force to the top 15 and the valve core 32 respectively.

[0087] In this embodiment, the two end faces of the spring body 37 extend orthogonally to the moving direction of the moving body 30 (the surfaces extending radially in the valve cylinder 14). Specifically, the end face of the metal wire constituting the helical spring extends in a direction orthogonal to the moving direction of the moving body 30. Alternatively, the end of the metal wire constituting the helical spring extends on the surface extending radially in the valve cylinder 14. In other words, the end of the metal wire constituting the helical spring extends along the circumferential direction of the valve shaft 34. Thus, the two end faces of the spring body 37 can respectively make surface contact with the top 15 and the valve core 32. As a result, the spring body 37 can apply force vertically to the top 15 and the valve core 32 respectively in the moving direction of the moving body 30.

[0088] When check valve 1 changes from the closed state to the open state, spring body 37 is compressed in the moving direction of moving body 30. Therefore, in the open state of check valve 1, spring body 37 exerts a force on valve core 32 downward in the moving direction of moving body 30, and spring body 37 exerts a force on valve core 32 in such a way that check valve 1 is in the closed state. In addition, even in the closed state of check valve 1, spring body 37 still exerts a force on valve core 32 downward in the moving direction of moving body 30. Therefore, in the closed state of check valve 1, valve core 32 is pressed against valve seat 12.

[0089] Next, the flow of fluid 200 when it passes through the check valve 1 of this embodiment will be described.

[0090] Figure 4 (a) is a velocity distribution diagram showing the velocity distribution of fluid 200 when check valve 1 is installed midway through the piping, allowing fluid 200 to flow at a velocity of 4.0 m / s to the upstream side of the piping of check valve 1. Furthermore, the lines shown in the fluid 200 indicate the direction of fluid flow.

[0091] Figure 4 (a) and Figure 4 The velocity distribution diagram in (b) is created by constructing a 3D model of the check valve corresponding to the shape of the check valve 1 in this embodiment, and 3D models of the upstream and downstream piping connected to the check valve. The flow velocity of the fluid flowing inside the check valve 1 is calculated using a numerical fluid dynamics simulation. This simulation is performed under the premise of fixing the position of the valve core 32 (corresponding to the valve opening described later) and allowing the flow of fluid 200 at a predetermined flow velocity. Regarding the above simulation, Figure 5 of (a) Figure 5 of (b) Figure 12 , Figure 13 (a) and Figure 13 The same applies to (b).

[0092] Figure 4 (a) and Figure 4 The valve opening degree of (b) is approximately 80%. Valve opening degree is an indicator of the degree of opening and closing of valve core 32. Setting the valve core 32 seated on valve seat 12 as 0% valve opening degree, and then adjusting the lower end of valve core 32 in the vertical direction (at...) Figure 4 In (a), the lower left portion of the valve core 32 is positioned at the same height as the upper surface of the piping section 11 in the vertical direction, and is defined as the valve opening of 100%. That is, when the valve opening is 0%, the fluid 200 does not substantially move from the primary flow path 40 to the secondary flow path 50. Furthermore, when the valve opening is 100%, the movement of the fluid 200 from the primary flow path 40 to the secondary flow path 50 of the piping section 11 is not substantially obstructed by the valve core 32. The valve opening is defined as the position of the valve core 32 in the vertical direction, using the positions of the valve core 32 at 0% and 100% as references. However, in this embodiment, the valve opening is 80% when the valve core 32 is at its highest position. In other words, in the check valve 1 of this embodiment, the lower end of the valve core 32 does not rise to the same height as the upper surface of the piping section 11 in the vertical direction, the maximum value of the valve opening is 80%, and the valve opening does not take a value greater than 80%. Specifically, when the valve core 32 moves upward in the moving direction of the moving body 30 to the position of 80% valve opening, the upper end 34b of the valve shaft 34 abuts against the top 15 (more specifically, the upper surface of the top cavity 15a), so the valve shaft 34 and the valve core 32 cannot move to a position higher than the position of 80% valve opening.

[0093] With the check valve 1 open, fluid 200 mainly flows from the primary flow path 40 to the secondary flow path 50 within the piping section 11. More specifically, fluid 200 flows into the valve cylinder 14 from the primary flow path 40 and flows out of the valve cylinder 14 into the secondary flow path 50.

[0094] As described above, the first mainstream of the fluid 200 flowing from the upstream side (primary flow path 40) to the downstream side (secondary flow path 50) through the interior of the valve cylinder 14 has a component in the direction of movement of the moving body 30 that is greater than the component in the direction of movement of the main axis. The direction of movement of the first mainstream refers to the average direction of movement of the first mainstream.

[0095] Here, the first mainstream is the main portion of the fluid 200 that flows into the valve cylinder 14 from the primary flow path 40 and out of the secondary flow path 50. That is, the portion of fluid 200 that flows into the valve cylinder 14 from the primary flow path 40 and out of the secondary flow path 50 without reverse flow is the first mainstream. In other words, fluid 200 that flows into the valve cylinder 14 from the primary flow path 40 but flows in the main axial direction from the secondary flow path 50 towards the primary flow path 40 is not included in the first mainstream. Specifically, the portion of fluid 200 flowing inside the valve cylinder 14 at a position lower than the valve core 32 in the direction of movement of the moving body 30 (…). Figure 4 The fluid in region A (b) shown in the diagram (200) may become the primary flow. In this embodiment, in Figure 4 In region A of (b), the fluid 200 flowing upstream (on the right) of valve shaft 34 has a vortex-like flow direction. On the other hand, in Figure 4 In region A of (b), the fluid 200 is located downstream (left) of valve shaft 34. Figure 4 The fluid 200 in region B (b) has a flow direction toward the secondary flow path 50. Therefore, the first mainstream of this embodiment can be set as the fluid 200 in the region B.

[0096] The first mainstream flowing from the primary flow path 40 to the lower end of the valve cylinder 14 is in the direction of the movement direction component of the larger moving body 30. Figure 4 The flow is directed towards the upper left in (a). Subsequently, the first main flow flows out from between the valve core 32 and the valve seat 12 into the secondary flow path 50.

[0097] Figure 5 (a) and Figure 5 (b) is a longitudinal sectional view of the check valve 1 when it is installed in the middle of the piping, showing the velocity distribution of the fluid 200 when the fluid 200 flows to the piping upstream of the check valve 1 at a velocity of 2.0 m / s and 3.0 m / s respectively. Figure 5 The valve opening in (a) is approximately 50%. Figure 5 The valve opening of (b) is about 70%.

[0098] In this embodiment, the larger the valve opening, the more the first mainstream flow direction has a component of the movement direction of the moving body 30. In other words, the greater the flow velocity of the fluid 200 flowing into the check valve 1, the more the first mainstream flow direction has a component of the movement direction of the moving body 30.

[0099] The larger the valve opening, the more compressed the spring body 37 is. To maintain the open state of the valve core 32, a larger upward force in the direction of movement needs to be applied to the valve core 32. As described above, when the valve opening is large, the flow direction of the first mainstream has a larger component in the direction of movement, thus making it easier to maintain the open state of the valve core 32. In addition, when the valve opening is small, it is easier to maintain the open state of the valve core 32. Compared with the case of a large valve opening, the flow direction of the first mainstream has a larger component in the direction of the main axis, thus making it easier for the fluid 200 to flow smoothly from upstream to downstream.

[0100] Furthermore, when the valve opening is 30% or more, the directional component of the moving body 30 in the first mainstream flow direction is consistently greater than the component in the main axis direction. When the valve opening is 50% or more, the directional component of the moving body 30 in the first mainstream flow direction is even more consistently greater than the component in the main axis direction. Moreover, when the valve opening is 80% or more, the directional component of the moving body 30 in the first mainstream flow direction is even more consistently greater than the component in the main axis direction.

[0101] In this embodiment, the check valve 1 has a flow direction guiding mechanism that guides the fluid 200 to flow in the moving direction of the moving body 30, thereby ensuring that the first main flow direction has a component in the moving direction of the moving body 30 that is greater than that in the main axis direction. The flow direction guiding mechanism in this embodiment has a predetermined structure.

[0102] For example, including at least a portion of the following structures, preferably at least two or more, more preferably at least three or more, thereby achieving the aforementioned first mainstream flow direction. However, as exemplified by the structure of Patent Document 1 described later, even if at least a portion of the following structures is included, there are cases where the aforementioned first mainstream flow direction cannot be achieved if a structure is included that obstructs the flow of the first mainstream in the moving direction of the moving body 30.

[0103] First, in this embodiment, as described above, the valve shaft 34 extends downward from the valve core 32 in the direction of movement of the moving body 30. Therefore, the fluid 200 flowing into the interior of the valve cylinder 14 from the primary flow path 40 can flow along the valve shaft 34 in the direction of movement of the moving body. In particular, in this embodiment, with the check valve 1 open, the valve shaft 34 extends from the valve core 32 to the lower end cylinder 16a and the ring portion 18c in the direction of movement of the moving body 30. Therefore, regardless of the valve opening degree, the flow direction of the fluid 200 is easily along the direction of the valve shaft 34.

[0104] Second, in this embodiment, when the check valve 1 is closed, the lower end 34a of the valve shaft 34 protrudes downward relative to the ring 18c in the moving direction of the moving body 30. In other words, when the check valve 1 is closed, the lower end 34a of the valve shaft 34 is positioned upstream of the ring 18c in the main axial direction. This facilitates the redirection of the flow direction of the fluid 200 flowing from upstream towards the moving direction of the moving body 30. In particular, in this embodiment, when the check valve 1 is closed, the lowermost end of the valve shaft 34 is positioned longitudinally lower than the apex of the protrusion 11e. Furthermore, in other words, in this embodiment, as will be detailed separately, the closer the lower end 34a of the valve shaft 34 is to the bottom surface of the pipe wall 19a, the longer the lower end 34a of the valve shaft 34 extends downward from the ring 18c in this moving direction. With this configuration, the flow direction of the fluid 200 can be more effectively redirected towards the moving direction of the moving body 30.

[0105] Third, in this embodiment, as described later, a support portion 18 (particularly the support portion 18 in the second support portion 18b located at a position lower than the valve shaft 34) has a moving direction component in its width direction, so that the fluid 200 can flow in a predetermined direction by changing the flow direction of the fluid 200 near the support portion 18.

[0106] Fourth, as detailed separately, the starting point of the upward slope 11c is located downstream of the lowest end of the lower cylinder 16a or the ring 18c. Therefore, the fluid 200 flowing from upstream collides with the upward slope 11c at a position downstream of the lowest end or the ring 18c. That is, the fluid 200 flows from the primary flow path 40 into the interior of the valve cylinder 14 primarily after passing the lowest end or the ring 18c. In other words, compared to the case where the starting point of the upward slope 11c is located upstream of the lowest end or the ring 18c, the flow direction of the fluid 200 flowing in the main axis direction changes more abruptly. In other words, compared to the case where the starting point of the upward slope 11c is located upstream of the lowest end or the ring 18c, the flow direction of the fluid 200 flowing in the main axis direction can change towards the direction with a larger component of the moving body 30's movement direction.

[0107] Fifth, as described later, the length direction of a support portion 18 (particularly the support portion 18 in the second support portion 18b positioned lower than the valve shaft 34) is inclined slightly radially relative to the valve cylinder 14. Specifically, the support portion 18 is inclined downwards towards the center of the valve cylinder 14 and towards the direction of movement of the moving body 30. Therefore, in the fluid 200, when viewed in the main axial direction, the portion closer to the center (the portion with the higher flow velocity in the fluid 200) contacts the second support portion 18b first. Thus, the flow direction of the fluid 200 can be more effectively redirected towards the direction of movement of the moving body 30.

[0108] The flow direction guiding mechanism is not limited to the first to fifth structures shown in this embodiment. For example, a member (excluding valve shaft 34) extending in the moving direction of the moving body 30 may also be disposed in the valve cylinder 14, and a protrusion such as a valve for changing the flow direction of the fluid 200 may also be disposed in the primary flow path 40 or the valve cylinder 14.

[0109] Preferably, the check valve 1 has the third and fifth configurations described above. More preferably, the check valve 1 has a second configuration in addition to the third and fifth configurations described above. Alternatively, more preferably, the check valve 1 has a fourth configuration in addition to the third and fifth configurations described above.

[0110] Alternatively, preferably, the check valve 1 has the first, second, and fourth configurations described above. More preferably, in addition to the first, second, and fourth configurations described above, the check valve 1 also has the third configuration described above. Alternatively, in addition to the first, second, and fourth configurations described above, the check valve 1 also has the fifth configuration described above.

[0111] Furthermore, in the check valve of Patent Document 1, regardless of whether the valve opening is small or large, the first mainstream flow direction does not have a component of the movement direction of the moving body (disc (16)) larger than the main axis direction. Specifically, in the check valve of Patent Document 1, it is clearly stated that the fluid passage from one side of the valve to the other side is substantially straight (page 1, lines 90 to 100 of Patent Document 1). More specifically, the check valve of Patent Document 1 partially lacks the aforementioned first structure, and in particular, lacks the second structure. In Patent Document 1, the valve core (disc (16)) is not fixed to the valve shaft (rod (17)), and in the closed state, the valve core is located at the lowermost end of the valve shaft. Therefore, in this closed state, the valve shaft does not extend downward from the valve core. In addition, the check valve of Patent Document 1 does not have the aforementioned third to fifth structures. Moreover, as in Patent Document 1 Figure 3As illustrated, in the check valve of Patent Document 1, the width direction of the blade (21) provided on the valve seat (15) is intersected with the moving direction of the valve core (disc (16)). Therefore, the fluid colliding with the blade (21) is guided to flow in a direction intersecting the moving direction of the valve core (disc (16)). That is, in Patent Document 1, the first mainstream flow is difficult to follow the moving direction of the moving body (disc (16)), and as a result, in Patent Document 1, the first mainstream flows linearly from upstream to downstream as described in that document.

[0112] Preferably, as described above, the first mainstream flow direction has a larger component of the moving body 30 in the direction of movement and the pressure loss of the fluid 200 when passing through the check valve 1 is small.

[0113] In this embodiment, the first main stream flows near the main axis. Specifically, as... Figure 4 (a) and Figure 4 As shown in diagram (b), when the valve opening is above 30%, the first main flow crosses the main shaft ( Figure 4 The flow occurs along the axis indicated by the single-dotted line in (a). This is achieved by positioning the lower end of the valve cylinder 14 (which is also the apex of the protrusion 11e) closer to the longitudinal bottom surface than the main shaft, and positioning the valve core 32 closer to the longitudinal top surface than the main shaft. The first main flow occurs near the main shaft, thereby reducing pressure loss before and after the flow of the check valve 1.

[0114] Furthermore, in this embodiment, the fluid 200 in the first mainstream near the valve shaft 34 (the right half of region B) flows in a direction with a larger upward component, while the fluid 200 in the first mainstream closer to the secondary flow path 50 (the left half of region B) flows in a direction with a larger leftward component. More specifically, the flow direction of the fluid in the first mainstream near the valve shaft 34 (the upstream (right) side of region B) has a larger directional component than the flow direction of the fluid 200 in the first mainstream closer to the secondary flow path 50 (the downstream (left) side of region B).

[0115] Furthermore, in this embodiment, the flow velocity of the fluid 200 in the portion of the first main flow path near the valve shaft 34 (the right half of region B) is lower than the flow velocity of the fluid 200 in the portion of the first main flow path closer to the secondary flow path 50 (the left half of region B). Specifically, the flow velocity is lower in the portion flowing towards the moving body 30 in the direction of movement of the valve shaft 34, and higher in the portion flowing towards the main axis direction that is separated from the valve shaft 34. As a result, the fluid 200 can push the valve core 32 upwards in the direction of movement of the moving body 30 and flow primarily from upstream to downstream in the direction of the main axis. With this structure, pressure losses before and after the flow of the check valve 1 can be reduced.

[0116] In this embodiment, as described above, the maximum valve opening is 80%. In other words, when the check valve 1 is fully open, the lower end of the valve core 32 is positioned below the upper surface of the piping section 11 in the vertical direction. When fluid 200 flows into the interior of the valve cylinder 14 from the primary flow path 40, a portion of the fluid 200 flows in the direction of movement of the moving body 30. Since the lower end of the valve core 32 is positioned below the upper surface of the piping section 11, the fluid 200 flowing into the interior of the valve cylinder 14 collides with the valve core 32 at a position below the upper surface of the piping section 11. As a result, the fluid 200 changes its flow direction at a position below the upper surface of the piping section 11, and the collided fluid 200 can flow along the main axis in approximately the center of the piping section 11. Thus, the fluid 200 flowing into the interior of the valve cylinder 14 flows out towards the approximately center, where it is less affected by friction with the inner wall of the piping section 11, allowing the fluid 200 to pass through the check valve 1 with minimal pressure loss.

[0117] In this embodiment, such as Figure 5 The second main flow of fluid flowing from valve cylinder 14 to secondary flow path 50 is specifically illustrated in (a). Figure 5 In region C of (a), the main flow of fluid 200 flows in a direction inclined relative to the main axis toward the bottom surface of the check valve. In other words, the second main flow flows obliquely downward relative to the main axis. Thus, the second main flow flows along the downward slope of the downstream flow path, thereby suppressing turbulence (flow of fluid that bounces back at the downward slope) near the downward slope.

[0118] The second main stream is the main part of the fluid 200 flowing from the inside of the valve cylinder 14 into the secondary flow path 50.

[0119] In this embodiment, the flow direction of the second mainstream has a main axis direction component and a vertical direction component. In this embodiment, the flow direction of the second mainstream has a main axis direction component that is larger than the vertical direction component.

[0120] In this embodiment, the smaller the valve opening, the greater the downward component of the second mainstream. Specifically, as... Figure 5 As shown in diagram (b), it is also similar to the situation when the valve opening is around 70%. Figure 5 Similarly, in the case illustrated in (a), the second mainstream flow has a downward component.

[0121] The second main channel has a width in the longitudinal direction. The longitudinal direction is the direction towards the side where the valve cylinder 14 is located in the valve box 10, namely the top surface (upper side), and the opposite side of the top surface, namely the bottom surface (lower side), with the main axis direction as the reference. That is, the longitudinal direction is consistent with the vertical direction of this embodiment.

[0122] In this embodiment, in the second mainstream, the flow velocity in the lower section near the bottom surface of the longitudinal center is greater than the flow velocity in the upper section near the top surface of the center. Therefore, even if, as described above, the direction of fluid flow from the valve cylinder (the flow direction of the second mainstream) is obliquely downward from the valve cylinder, the higher flow velocity in the lower section allows the flow direction of the mainstream of fluid 200 to easily and naturally return to a horizontal direction. As will be described later, such a velocity distribution can be achieved through the extension 11e of the valve box 10 (refer to...). Figure 2 This can be achieved by adjusting the amount of the valve shaft 34, or by other construction methods. For example, the aforementioned flow velocity distribution can also be achieved by adjusting the position of the valve shaft 34 or the lower end cylinder 16a.

[0123] Specifically, Figure 4 The average flow velocity in the lower half of region C (lower watershed) shown in (b) is greater than the average flow velocity in the upper half of region C (upper region). More specifically, the higher flow velocity regions in region C (regions above 6.5 m / s, region D) are biased towards the lower half of region C.

[0124] In this embodiment, the bottom surface of the piping section 11 extends longitudinally towards the top surface (upward). Specifically, a portion of the bottom surface of the piping section 11, including the valve seat 12, extends upward. More specifically, the bottom surface of the piping section 11 includes an upward inclined surface 11c and a downward inclined surface 11d. The upward inclined surface 11c is a portion of the bottom surface that extends obliquely upward from the upstream side toward the valve seat 12 on the primary flow path 40 side. The downward inclined surface 11d is a portion of the bottom surface that extends obliquely downward from the valve seat 12 toward the downstream side on the secondary flow path 50 side. The portion extending upward from the bottom surface of the piping section 11 is referred to as the protrusion 11e. The protrusion 11e can also be described as a mountain-shaped portion formed by the upward inclined surface 11c and the downward inclined surface 11d in the longitudinal section of the check valve 1. In this embodiment, the top of or near the protrusion 11e is also a portion of the valve seat 12.

[0125] In this embodiment, the apex of the protrusion 11e is positioned on the bottom side in the longitudinal direction compared to the main shaft of the piping section 11.

[0126] In this embodiment, such as Figure 2 As illustrated, a portion (ring portion 18c or lower end cylinder portion 16a, or both) supporting the lower end of the valve shaft 34 in the valve housing 10 is positioned longitudinally above the top surface (upper side in the vertical direction) of the protrusion 11e. In other words, this portion is positioned higher than the lower end of the valve seat 12 (the lower side of the annular valve seat in the vertical direction). Furthermore, when viewed in the main axial direction (front-back direction), at least a portion of the ring portion 18c or the lower end cylinder portion 16a is disposed inside the annular valve seat 12. Therefore, this portion is less likely to obstruct the movement of the fluid 200 as it moves from the primary flow path 40 to the secondary flow path 50. Additionally, with less obstruction, the flow velocity in the lower region of the second main flow path is less likely to decrease. In other words, the flow velocity in the lower region of the second main flow path is more likely to increase.

[0127] In this embodiment, the extension direction of the upward ramp 11c, viewed from the width direction (left-right direction) of the check valve 1, has a principal axis component larger than the longitudinal component. That is, the upward ramp 11c is a gentle upward ramp. Thus, the upward ramp 11c extends along the principal axis direction, thereby reducing the protrusion amount of the protrusion 11e, and consequently increasing the inner diameter of the valve seat 12, allowing for smoother movement of the fluid 200. Here, when the upward ramp 11c is curved, the extension direction of the upward ramp 11c, viewed from the left-right direction, is the direction that connects the starting point of the upward ramp 11c (the lowermost part of the upward ramp 11c, which is also the uppermost part of the upward ramp 11c) and the apex of the upward ramp 11c (the uppermost part of the upward ramp 11c, which is also the lowermost part of the upward ramp 11c) with a straight line.

[0128] Furthermore, in this embodiment, the starting point of the upward inclined surface 11c is positioned at least partially downstream in the main axial direction than a portion (ring portion 18c or lower end cylinder portion 16a) of the lower end portion 34a supporting the valve shaft 34 in the valve box 10. Therefore, the movement of the fluid 200 guided upward in the moving direction of the moving body 30 by the upward inclined surface 11c is less likely to be obstructed by the ring portion 18c or the lower end cylinder portion 16a.

[0129] Furthermore, in this embodiment, the apex of the protrusion 11e (the boundary between the ascending inclined surface 11c and the descending inclined surface 11d) is located downstream of the lower end cylinder 16a in the main axial direction. More specifically, the apex of the protrusion 11e is located downstream of the lower end cylinder 16a in the main axial direction. As a result, the movement of the fluid 200 guided upward in the moving direction of the moving body 30 by the ascending inclined surface 11c is less likely to be obstructed by the lower end cylinder 16a.

[0130] like Figure 2 As illustrated, in this embodiment, the upper surface (the wall portion 19 on the top side in the longitudinal direction) of the piping portion 11 that divides the primary flow path 40 has a second protrusion 11f extending towards the bottom side (downward). In this embodiment, the top of or near the second protrusion 11f is also part of the valve seat 12. The surface of the second protrusion 11f includes a slope 11g that slopes downward from upstream to downstream. In this embodiment, the extension direction of the slope 11g when viewed from the width direction of the check valve 1 includes a main axis direction component that is larger than the longitudinal component. Thus, the slope 11g extends along the main axis direction, thereby reducing the extension amount of the second protrusion 11f, and therefore increasing the inner diameter of the valve seat 12, enabling smoother movement of the fluid 200.

[0131] In addition, in this embodiment, the apex of the second protrusion 11f (the part that extends to the lowest point in the second protrusion 11f) is positioned upstream in the main axis direction, at least partially above the part (ring 18c or lower end cylinder 16a) that supports the lower end 34a of the valve shaft 34 in the valve box 10.

[0132] Furthermore, in this embodiment, the apex of the second protrusion 11f is positioned longitudinally closer to the top surface than a portion (ring portion 18c or lower end cylinder portion 16a) of the lower end portion 34a supporting the valve shaft 34 in the valve housing 10. More specifically, the apex of the second protrusion 11f is positioned longitudinally closer to the top surface than the entire ring portion 18c and the entire lower end cylinder portion 16a.

[0133] As described above, the lower end of the valve shaft 34 is supported by the support portion 18. Figure 6 As illustrated, in this embodiment, the support portion 18 includes a first support portion 18a and a second support portion 18b. The first support portion 18a and the second support portion 18b extend radially along the valve cylinder 14 from the ring portion 18c toward the wall portion 19 of the valve cylinder 14.

[0134] In this embodiment, the first support portion 18a extends along the width direction of the check valve 1 and extends orthogonally to the moving direction. On the other hand, as... Figure 2As illustrated, the second support portion 18b extends longitudinally (vertically), and extends obliquely toward the bottom surface of the check valve 1 in the direction of movement of the moving body 30 toward the lower end 34a of the valve shaft 34, relative to the direction of movement of the moving body 30 (radial direction of the valve cylinder 14). Here, "extending in the vertical direction" means that the extension direction of the second support portion 18b has a vertical component. "Obliquely extending toward the bottom surface of the check valve 1 in the direction of movement of the moving body 30 toward the lower end 34a of the valve shaft 34, relative to the radial direction of the valve cylinder 14" means that the second support portion 18b extends in a direction obliquely to the radial direction of the valve cylinder 14, and that the second support portion 18b is oblique relative to this radial direction in such a way that it approaches the lower side of the moving body 30 as it approaches the lower end 34a.

[0135] According to the above structure, the valve shaft 34 can be firmly held and the collision between the fluid 200 and the valve shaft 34 or valve core 32 can be prevented from causing damage to the valve shaft 34 or valve core 32. Specifically, firstly, the first support portion 18a extending in the horizontal direction is orthogonal to the valve shaft 34, thereby fully realizing the function of the support portion 18, such as firmly supporting the lower end 34a of the valve shaft 34. Moreover, the end of the second support portion 18b located on the central side of the flow path is arranged to protrude upstream, thereby slowing down the fluid 200 in the center of the fastest flow path due to collision with the end of the second support portion 18b, and preventing the fluid 200 from flowing rapidly into the valve cylinder 14.

[0136] In this embodiment, each support portion 18 has a plate shape. More specifically, the plate-shaped support portion 18 extends in both the length and width directions, as described later. The support portion 18 is a member that is longer in a predetermined direction, which is the length direction. The length direction of the support portion 18 coincides with the direction in which the support portion 18 extends from the wall portion 19 to the lower end portion 34a. The width direction is a direction orthogonal to both the plate thickness direction and the length direction.

[0137] exist Figure 2 The cross-sectional shape of the first support portion 18a is shown in dashed lines. In this embodiment, the width direction of the first support portion 18a is along the main axis direction (front-to-back direction). Furthermore, the width direction of the second support portion 18b is along the moving direction. Here, "the width direction of the support portion 18 is along a predetermined direction" means that this width direction has a predetermined directional component. Specifically, the width direction of the support portion 18 has a predetermined directional component that is larger than the component of the direction orthogonal to the predetermined direction.

[0138] According to the above structure, the fluid 200 can be guided from the upstream side to the downstream side along the main axis direction using the first support 18a, and the fluid 200 can be guided upward in the moving direction of the valve core 32 using the second support 18b. That is, pressure loss can be suppressed and the flow direction can be maintained in a way that makes it easy to keep the valve core 32 in an appropriately open state.

[0139] In this embodiment, such as Figure 6 As shown in the figure, the thickness direction of the first support portion 18a is longitudinal (vertical direction), and the thickness direction of the second support portion 18b is the width direction (left-right direction) of the check valve 1. This reduces the area of ​​the support portion 18 when viewed from the rear. Consequently, the movement of the fluid 200 flowing in from upstream is less likely to be obstructed by the support portion 18.

[0140] In this embodiment, it can also be, as follows: Figure 7 As shown in (a), a groove 16d extending in the moving direction (vertical direction in the figure) of the moving body 30 is formed in a portion of the check valve 1 on the bottom side of the inner wall (inner wall 16c) of the cylinder 16 (lower cylinder 16a). This groove 16d allows the valve shaft 34 to slide straight without twisting in the moving direction of the valve core 32.

[0141] In this embodiment, two grooves 16d are formed on the inner wall 16c of the cylinder. However, one groove 16d or three or more grooves 16d may also be formed on the inner wall 16c of the cylinder. Furthermore, in this embodiment, the groove 16d is formed only in a portion of the lower end side of the inner wall 16c of the cylinder, and not in a portion of the upper end side. Alternatively, the groove 16d may extend from the upper end to the lower end of the inner wall 16c of the cylinder.

[0142] In this embodiment, such as Figure 7 As shown in (b), a groove 34c is formed on the surface (outer peripheral surface) of the lower end 34a, extending in the moving direction (up and down direction in the figure) of the moving body 30.

[0143] Both the groove 16d on the inner wall 16c of the cylinder and the groove 34c on the surface of the lower end 34a can be formed, or the groove 16d can be not formed on the inner wall 16c of the cylinder, but the groove 34c can be formed on the surface of the lower end 34a. In this embodiment, the groove 34c is only formed on a portion of the lower end surface of the lower end 34a, and not on a portion of the upper end surface.

[0144] Alternatively, similar to the groove 16d of the lower end cylinder 16a, a groove (not shown) extending in the moving direction of the moving body 30 may be formed locally on the inner wall of the upper end cylinder 16b on the bottom side of the check valve 1.

[0145] Similar to the groove 34c on the surface of the lower end 34a, a groove (not shown) extending in the moving direction of the moving body 30 may also be formed on the surface (outer peripheral surface) of the upper end 34b of the valve shaft 34.

[0146] In this embodiment, such as Figure 8 (a) and Figure 8 As illustrated in (b), a sealing recess 36a is formed in the center of the lower surface 36b facing the bottom surface of the check valve 1 in the sealing portion 36. The sealing recess 36a is a recess that is recessed towards the interior of the sealing portion 36 relative to the outer periphery of the lower surface 36b of the sealing portion 36. Alternatively, the depth dimension D1 of the bottom surface side of the sealing recess 36a may be larger than the depth dimension of other parts. For example, the depth dimension D1 may be larger than the depth dimension D2 of the top surface side of the sealing recess 36a. Or, the depth dimension D1 may be larger than the depth dimension of the right or left side of the sealing recess 36a. Figure 8 (a) and Figure 8 In (b), the depth of the sealing recess 36a and the relationship between the depth dimension D1 and the depth dimension D2 are exaggeratedly illustrated. Alternatively, the depth of the sealing recess 36a or the difference between the depth dimension D1 and the depth dimension D2 could be shown. Figure 8 (a) or Figure 8 The difference shown in (b) is small.

[0147] A sealing recess 36 is formed in the sealing portion 36, and a local sealing recess 36a is formed on the bottom side at a deeper depth, thereby effectively suppressing the situation where the sealing portion 36 deviates from the second gripping portion 39 due to the fluid 200 flowing out from the valve cylinder 14 at a high speed.

[0148] In this embodiment, when viewed in the moving direction of the moving body 30, the sealing recess 36a is formed in a manner that surrounds the valve shaft 34. Alternatively, when viewed in the moving direction of the moving body 30, the sealing recess 36a may be formed only in the area below the lower surface 36b (bottom surface side).

[0149] <Second Implementation>

[0150] Figure 9 This is a perspective view showing an example of the check valve 1 according to this embodiment. Additionally, Figures 12 to 13 (b) indicates the velocity distribution of fluid 200 when check valve 1 is installed in the middle of the piping and fluid 200 flows to the piping upstream of check valve 1 at velocities of 4.0 m / s, 2.0 m / s, and 3.0 m / s respectively.

[0151] First, a general overview of the check valve 1 in this embodiment will be given.

[0152] In this embodiment, such as Figure 12 As illustrated, the first main flow of fluid 200 (in this embodiment) passes through the interior of valve cylinder 14 from the upstream side toward the downstream side. Figure 12 The fluid in region B (the main flow direction) has a component in the direction of movement of the moving body 30 that is more abundant than that in the direction of the main axis.

[0153] Next, the check valve 1 of this embodiment will be described in detail.

[0154] The check valve 1 in this embodiment differs from the valve box 10 in the lower end 34a of the valve shaft 34 described above in its construction.

[0155] In this embodiment, the check valve 1 has a particular configuration such that the first mainstream flow direction of the fluid 200 has a component in the movement direction of the moving body 30 that is greater than the component in the main axis direction.

[0156] First, in this embodiment, the valve shaft 34 extends downward from the valve core 32 in the moving direction of the moving body 30. Furthermore, when the check valve 1 is closed, the lower end 34a of the valve shaft 34 protrudes downward relative to the ring portion 18c in the moving direction of the moving body 30. Moreover, the width of a support portion 18 (particularly the support portion 18e located lower than the valve shaft 34) has a component in the moving direction. Additionally, the starting point of the upward inclined surface 11c is located downstream of the lower end of the lower end cylinder portion 16a or the ring portion 18c.

[0157] First, in this embodiment, as Figure 10 and Figure 14 As shown, the lower end cylindrical portion 16a is supported by two support portions 18. Specifically, the two support portions 18 (upper support portion 18d and lower support portion 18e) extend upward and downward respectively from the ring portion 18c connected to the lower end cylindrical portion 16a. In this embodiment, no support portions 18 are provided on both sides of the ring portion 18c in the width direction (left-right direction) of the check valve 1, and the fluid 200 can pass through the areas on both sides.

[0158] Specifically, the upper support portion 18d protrudes from the upper surface of the piping portion 11 (the second protrusion 11f on which the valve seat 12 is formed) toward the ring portion 18c. Furthermore, the lower support portion 18e protrudes from the middle of the upward inclined surface 11c in the main shaft direction toward the ring portion 18c. In other words, the lower support portion 18e protrudes toward the ring portion 18c from a position upstream of the top of the protrusion 11e in the upward inclined surface 11c.

[0159] like Figure 10 or Figure 11As illustrated, similar to the first embodiment, the upper support portion 18d and the lower support portion 18e have a plate shape. The thickness direction of the upper support portion 18d and the lower support portion 18e is in the left-right direction. The length direction of the lower support portion 18e is orthogonal to the movement direction of the moving body 30 (radial direction of the valve cylinder 14). On the other hand, the length direction of the upper support portion 18d is inclined relative to the radial direction of the valve cylinder 14. Specifically, the length direction of the upper support portion 18d is inclined relative to the radial direction of the valve cylinder 14 in a downward direction in the movement direction of the moving body 30, towards the lower end of the valve shaft 34.

[0160] In this embodiment, the apex of the protrusion 11e (a portion of the valve seat 12 on the longitudinal bottom surface side) is not positioned lower than a portion of the valve box 10 (such as the ring portion 18c) supporting the lower end 34a of the valve shaft 34. More specifically, the apex of the protrusion 11e is positioned higher in the longitudinal direction than a portion of the ring portion 18c.

[0161] In this embodiment, the surface of the valve core 32 facing upstream (the lower surface of the valve core 32 and the lower surface of the second gripping portion 39 facing the moving direction of the moving body 30) is a plane extending radially in the valve cylinder 14. In this embodiment, the second gripping portion 39 is solidly formed.

[0162] The check valve 1 in this embodiment has the same characteristics as the first embodiment.

[0163] The second main flow of fluid 200 flowing from valve cylinder 14 to secondary flow path 50 flows in a direction inclined relative to the main shaft direction toward the bottom surface of check valve 1.

[0164] In the second main stream, the flow velocity in the lower basin on the bottom side of the longitudinal center is greater than the flow velocity in the upper basin on the top side of the center.

[0165] In addition, the two ends of the valve shaft 34 (upper end 34b and lower end 34a) are supported on the wall 19 of the valve box 10.

[0166] In this embodiment, the width direction of the support portion 18 (upper support portion 18d and lower support portion 18e) is along the moving direction of the moving body 30.

[0167] Additionally, a groove 16d extending in the moving direction of the moving body 30 is partially formed on the bottom surface side of the check valve 1 on the inner wall of the lower end cylinder 16a.

[0168] Furthermore, a sealing recess 36a is formed in the center of the lower surface 36b of the sealing portion 36, and the depth dimension of the bottom side of the sealing recess 36a is larger than the depth dimension of the other parts.

[0169] Furthermore, the present invention is not limited to the above-described embodiments; any variations, modifications, or other forms that achieve the purpose of the present invention are also permitted.

[0170] The following variations can be appropriately combined.

[0171] The above implementation methods incorporate the following technical concepts.

[0172] (1) A check valve, which is a straight-pipe type inclined-rise check valve for allowing fluid to flow from an upstream side to a downstream side inside, wherein the check valve comprises: a valve seat; a movable body capable of linearly reciprocating to a closed state in contact with the valve seat and an open state separated from the valve seat; a valve box containing a valve cylinder extending in the movement direction of the movable body and for the movable body to move inside, the valve seat being fixed to the valve box; a primary flow path located upstream of the valve cylinder, with the main axis direction of the straight line as its axis; and a secondary flow path located downstream of the valve cylinder, with the main axis direction as its axis, the first main flow direction of the fluid flowing from the upstream side to the downstream side through the interior of the valve cylinder having a component of the movement direction of the movable body that is more abundant than the component of the main axis direction.

[0173] (1-1) According to the check valve of (1), the flow direction of the fluid in the portion of the first main flow near the valve shaft has a component of the movement direction that is greater than the flow direction of the fluid in other portions of the first main flow that are closer to the secondary flow path than that portion.

[0174] (1-2) According to the check valve of (1-1), wherein the flow velocity of the fluid in the portion of the first main flow path closer to the valve shaft is lower than the flow velocity of the fluid in the other portions of the first main flow path closer to the secondary flow path 50 than that portion.

[0175] (2) According to the check valve of (1), wherein the second mainstream of the fluid flowing out from the valve cylinder into the secondary flow path flows in a direction inclined relative to the main axis towards the bottom surface of the check valve.

[0176] (2-1) According to the check valve described in (2), the smaller the valve opening, the greater the component of the second mainstream in the direction connecting the top and bottom surfaces of the check valve.

[0177] (3) According to the check valve of (2), wherein the second mainstream has a width in the longitudinal direction of the side where the valve cylinder is provided in the valve box, i.e. the top side, and the opposite side of the top side, i.e. the bottom side, with the main axis direction as a reference, and in the second mainstream, the flow velocity of the lower flow area closer to the bottom side than the center of the longitudinal direction is greater than the flow velocity of the upper flow area closer to the top side than the center.

[0178] (4) The check valve according to any one of (1) to (3), wherein the movable body comprises: a valve core supported on the valve seat in the closed state; and a valve shaft extending in two directions from the valve core toward the moving direction, the two ends of the valve shaft being supported on the wall of the valve housing.

[0179] (5) According to (4), the bottom end of the valve shaft on the bottom side of the check valve is supported by two or more support portions that protrude from the wall of the valve box and extend toward the bottom end. The first support portion extends along the width direction of the check valve and is orthogonal to the moving direction. The second support portion extends longitudinally along the side where the valve cylinder is located in the valve box, i.e., the top side, and the opposite side of the top side, i.e., the bottom side, with the main shaft direction as a reference. It is inclined toward the bottom end and toward the bottom side of the check valve in the moving direction relative to the direction orthogonal to the moving direction.

[0180] (6) The check valve according to (5), wherein the support portion has a plate shape, the support portion extends in a length direction extending from the wall portion to the lower end and in a width direction orthogonal to the plate thickness direction and the length direction, the width direction of the first support portion is along the main axis direction, and the width direction of the second support portion is along the movement direction.

[0181] (6-1) According to the check valve described in (6), the thickness direction of the first support is longitudinal, and the thickness direction of the second support is the width direction of the check valve.

[0182] (7) The check valve according to any one of (4) to (6), wherein the lower end of the valve shaft on the bottom side of the check valve is inserted into the cylindrical portion fixed to the wall of the valve box, and a groove extending in the moving direction is formed on a portion of the bottom side of the check valve on the inner wall of the cylindrical portion.

[0183] (7-1) According to (7), a check valve is formed on the outer peripheral surface of the lower end, which extends in the direction of movement of the moving body.

[0184] (8) The check valve according to any one of (4) to (7), wherein the valve core comprises: a sealing portion that is in close contact with the valve seat in the closed state; a first holding portion disposed on the top surface side of the valve cylinder of the sealing portion; and a second holding portion disposed on the bottom surface side of the check valve of the sealing portion, the sealing portion being sandwiched between the first holding portion and the second holding portion in the moving direction, wherein a sealing recess is formed in the sealing portion at the center of the lower surface facing the bottom surface side of the check valve, the sealing recess having a depth dimension of a portion of the bottom surface side of the sealing recess that is recessed toward the interior of the sealing portion compared to the outer periphery of the lower surface, the depth dimension of the sealing recess being larger than the depth dimension of other portions.

[0185] (9) The check valve according to any one of (4) to (8), wherein the upper end of the valve shaft on the top surface side of the check valve is inserted into the upper end cylinder fixed at the top of the valve box, and in the closed state of the check valve, the separation distance between the lower end of the valve shaft and the pipe wall portion dividing the pipe portion extending in the main shaft direction in the moving direction is smaller than the insertion depth of the upper end of the valve shaft into the upper end cylinder.

[0186] (10) The check valve according to any one of (4) to (9), wherein the insertion depth of the lower end of the valve shaft in the open state of the check valve into the lower end cylinder is greater than the separation distance between the lower end of the valve shaft in the closed state of the check valve and the pipe wall portion that divides the pipe portion extending in the main shaft direction.

[0187] (11) The check valve according to any one of (1) to (10), wherein the larger the valve opening, the more the first mainstream flow direction has the movement direction component of the moving body.

[0188] (12) The check valve according to any one of (1) to (11), wherein the greater the flow velocity of the fluid flowing into the check valve, the more the first mainstream flow direction has the movement direction component of the moving body.

[0189] (13) The check valve according to any one of (4) to (10) of reference (3), wherein the valve housing has a piping portion extending in the direction of the main shaft, the bottom surface of the piping portion including an extension extending toward the top surface side in the longitudinal direction, and a portion of the lower end of the valve shaft in the valve housing is partially disposed at a position closer to the top surface side in the longitudinal direction than the extension.

[0190] (14) The check valve according to any one of (4) to (10), wherein the valve box has a piping portion extending in the main axis direction, the bottom surface of the piping portion including an upward inclined surface that slopes upward from the upstream side to the downstream side toward the top surface side in the longitudinal direction, the starting point of the upward inclined surface being disposed at a position at least partially downstream of the lower end of the valve cylinder supported in the valve box.

[0191] (15) According to (13) the check valve, wherein the apex of the protrusion is located downstream of the lower end cylinder in the main axis direction.

[0192] (16) The check valve according to any one of (4) to (10), wherein the valve box has a piping portion extending in the main axis direction, wherein a portion of the piping portion dividing the primary flow path 40 includes a second protrusion extending toward the bottom side in the longitudinal direction, the apex of the second protrusion being disposed at a position at least partially upstream in the main axis direction than a portion of the portion supporting the lower end of the valve shaft in the valve box.

[0193] (17) The check valve according to (1), wherein the valve shaft extends from the valve core toward the bottom surface of the check valve in the direction of movement.

[0194] (18) The check valve according to (1) or (17), wherein, in the closed state of the check valve, the lower end of the valve shaft protrudes downward relative to the ring portion in the direction of movement of the moving body.

[0195] (19) The check valve according to any one of (1), (17) and (18), wherein the width direction of one support has a component of the movement direction.

[0196] (20) The check valve according to any one of (1), (17), (18) and (19), wherein the starting point of the upward slope of the pipe wall is located at a position downstream of one end of the lower cylinder or the ring.

[0197] (21) The check valve according to any one of (1), (17), (18), (19) and (20), wherein a support is inclined toward the bottom surface of the check valve in the direction of movement of the moving body as it moves toward the center of the valve cylinder.

[0198] (22) According to (4) the check valve, wherein the valve shaft extends from the valve core toward the bottom side of the check valve in the moving direction, and in the closed state of the check valve, the lower end of the valve shaft protrudes downward relative to the ring in the moving direction of the moving body, and the starting point of the upward inclined surface of the pipe wall is located at a position downstream of the lower end cylinder or the ring.

[0199] (23) According to (4) the check valve, wherein the width direction of one support has a component of the moving direction, and the support is inclined in such a way as it moves toward the bottom surface of the check valve in the moving direction of the moving body toward the center of the valve cylinder.

[0200] (24) According to (4) the check valve, wherein the valve shaft extends from the valve core toward the bottom surface of the check valve in the direction of movement, and the starting point of the upward slope of the pipe wall is located at a position downstream of the lower end of the cylinder or the ring.

[0201] (25) According to (4) the check valve, wherein the valve shaft extends from the valve core toward the bottom surface of the check valve in the moving direction, and in the closed state of the check valve, the lower end of the valve shaft protrudes downward relative to the ring portion in the moving direction of the moving body.

[0202] (26) According to (4), the valve shaft extends from the valve core toward the bottom surface of the check valve in the moving direction, and in the closed state of the check valve, the lower end of the valve shaft protrudes downward relative to the ring in the moving direction of the moving body, and a support portion is inclined toward the bottom surface of the check valve in the moving direction of the moving body as it moves toward the center of the valve cylinder.

[0203] Explanation of reference numerals in the attached figures

[0204] 1. Check valve; 10. Valve box; 11. Piping section; 11a. Inlet; 11b. Outlet; 11c. Upward inclined surface; 11d. Downward inclined surface; 11e. Extension; 11f. Second extension; 11g. Inclined surface; 12. Valve seat; 14. Valve cylinder; 15. Top; 15a. Top cavity; 15b. Fastener; 16. Cylinder section; 16a. Lower cylinder section; 16b. Upper cylinder section; 16c. Inner wall of cylinder section; 16d. Groove section; 17. Flange section; 18. Support section; 18a. First support section; 18b. Second support section; 18c. Ring section; 18d. Upper support section; 18 e. Lower support portion; 19. Wall portion; 19a. Piping wall portion; 19b. Valve cylinder wall portion; 30. Moving body; 32. Valve core; 34. Valve shaft; 34a. Lower end portion; 34b. Upper end portion; 34c. Groove portion; 34d. Screw receiving portion; 35. Threaded screw; 36. Sealing portion; 36a. Sealing recess; 36b. Lower surface; 37. Spring body; 38. First holding portion; 38a. Recess; 38b. Hollow portion inside the valve core; 39. Second holding portion; 39a. Recess; 39b. Hollow portion at the lower end; 39c. Hollow portion; 40. Primary flow path; 50. Secondary flow path; 200. Fluid.

Claims

1. A check valve, which is a straight-pipe joint type inclined-lift check valve for allowing fluid to flow internally from upstream to downstream, wherein, The check valve includes: Valve seat; A movable body capable of linearly reciprocating between a closed state in close contact with the valve seat and an open state separated from the valve seat; A valve box comprising a valve cylinder extending in the direction of movement of the movable body and for the movable body to move inside, the valve seat being fixed to the valve box; A primary flow path, located upstream of the valve cylinder, with its main axis as the center; and The secondary flow path is located downstream of the valve cylinder, with the main axis direction as its center. The first mainstream flow of the fluid from the upstream side toward the downstream side through the interior of the valve cylinder has a component in the direction of movement of the moving body that is greater than that in the direction of the main axis.

2. The check valve according to claim 1, wherein, The second main flow of the fluid flowing out of the valve cylinder into the secondary flow path flows in a direction inclined relative to the main axis toward the bottom surface of the check valve.

3. The check valve according to claim 2, wherein, The second main stream has a width in the longitudinal direction, taking the main shaft direction as a reference, toward the side in the valve box where the valve cylinder is located, i.e., the top surface side, and the opposite side of the top surface side, i.e., the bottom surface side. In the second main stream, the flow velocity in the lower flow region (between the center and bottom surface) is greater than the flow velocity in the upper flow region (between the center and top surface).

4. The check valve according to any one of claims 1 to 3, wherein, The mobile body includes: Valve core, which is supported on the valve seat in the closed state; and A valve shaft that extends from the valve core in two directions in the direction of movement. The two ends of the valve shaft are supported by the wall of the valve box.

5. The check valve according to claim 4, wherein, The lower end of the valve shaft on the bottom side of the check valve is supported by two or more support portions that protrude from the wall of the valve box and extend toward the lower end. The first support portion extends along the width direction of the check valve and is orthogonal to the direction of movement. The second support portion extends longitudinally along the side where the valve cylinder is located in the valve box, i.e., the top surface side, and the opposite side of the top surface side, i.e., the bottom surface side, with the main axis direction as a reference. It is inclined toward the lower end and toward the bottom surface side of the check valve in the movement direction relative to a direction orthogonal to the movement direction.

6. The check valve according to claim 5, wherein, The support portion has a plate shape. The support extends in a length direction from the wall portion to the lower end and in a width direction orthogonal to the plate thickness direction and the length direction. The width direction of the first support portion is along the main axis direction. The width direction of the second support portion is along the direction of movement.

7. The check valve according to any one of claims 4 to 6, wherein, The lower end of the valve shaft, on the bottom side of the check valve, is inserted into the cylindrical portion fixed to the wall of the valve box. A groove extending in the direction of movement is formed on a portion of the bottom surface of the check valve on the inner wall of the cylinder.

8. The check valve according to any one of claims 4 to 7, wherein, The valve core includes: A sealing part that is in close contact with the valve seat in the closed state; The first gripping part is disposed on the top surface side of the valve cylinder of the sealing part; as well as The second gripping part is disposed on the bottom surface side of the check valve of the sealing part. The sealing part is sandwiched between the first gripping part and the second gripping part in the direction of movement. In the sealing portion, a sealing recess is formed at the center of the lower surface facing the bottom surface of the check valve, which is recessed towards the interior of the sealing portion compared to the outer periphery of the lower surface. The depth dimension of the bottom side of the sealing recess is larger than the depth dimension of other parts.

Images