Check valve device

Abstract

To provide a check valve device that can stably support the biasing means by preventing diagonal displacement of the biasing means, and that is also easy to assemble. [Solution] The coil spring end 10a is supported in the support space 35 of the spring receiving portion 3, and the outer guide 31 and inner guide 32 have an outer tapered surface 31a and an inner tapered surface 32a, respectively. Therefore, even if the coil spring 10 is misaligned in an oblique direction, the coil spring end 10a is smoothly guided along the outer tapered surface 31a or the inner tapered surface 32a and is reliably positioned to contact the contact surface 30. In addition, because the coil spring 10 is guided by the outer tapered surface 31a and the inner tapered surface 32a, assembly work can be easily performed.

Description

Technical Field

[0001] The check valve device according to the present application has biasing means such as a coil spring that biases the valve body, and relates to the technology of the configuration of a check valve device that opens or closes the valve by movement of the valve body.

Background Art

[0002] A check valve is a valve provided in a fluid flow path, and has a mechanism for preventing backflow of fluid due to back pressure. For example, piping installed in an industrial plant transfers high-temperature and high-pressure steam in a predetermined direction (forward direction), and drain (condensed water) generated from the steam flows together with the steam in this piping. In order to prevent such backflow of fluids such as steam and drain, check valves are provided at necessary positions on the piping.

[0003] There are various structural types of check valves, including swing check valves, lift check valves, and disc check valves, which are known. Among these, for example, a disc check valve incorporates a valve seat and a movably arranged disc-shaped disc valve inside its main body. This disc valve is positioned so as to block the flow path formed in the main body of the check valve, and is biased in a direction in contact with the valve seat surface of the valve seat by biasing means such as a coil spring.

[0004] When fluid flows in the forward direction from the inlet of the check valve, the pressure on the primary side, which is the fluid inlet side, becomes greater than the pressure on the secondary side, which is the outlet side. As a result, the coil spring is compressed, the disc valve translates in the direction of moving away from the valve seat to open the flow path and open the valve, allowing the fluid to flow in the forward direction. Then, the fluid passes through the gap between the inner surface of the main body and the side surface of the disc valve, and flows out to the secondary side from the outlet of the check valve.

[0005] In contrast, when back pressure occurs where the primary side pressure becomes lower than the secondary side pressure, and fluid flows backward and intrudes from the outlet, the disc valve translates under the fluid pressure and the repulsive force of the coil spring, seats on the valve seat surface of the valve seat to block the flow path and close the valve, and the backflow of fluid is automatically blocked by the check valve.

[0006] Incidentally, depending on the location where a check valve is installed, the fluid pressure of the fluid flowing in the forward direction may be low. For check valves installed in such locations, biasing means such as coil springs with a small spring constant and relatively softness are used to ensure proper operation. However, when using coil springs with a small spring constant, the coil spring may move laterally perpendicular to the biasing direction inside the check valve, causing displacement of the coil spring. When the coil spring is displaced, the repulsive force acting on the valve body becomes uneven, and the valve may not close properly.

[0007] As a check valve to prevent misalignment of such coil springs, there is a technology described in Patent Document 1 below. This check valve has a coil spring 19 that biases the valve body 6 toward the annular valve seat 5, and the base end portion of this coil spring 19 is in contact with a spring holder 18.

[0008] The spring retainer 18 has an upper protrusion 21 and a lower protrusion 22 that are bent at the top and bottom and protrude toward the valve body 6, and these upper protrusion 21 and lower protrusion 22 loosely hold the upper and lower parts of the outer circumference of the coil spring 19. In addition, a second upper protrusion 23 and a second lower protrusion 24 are fixed to the spring retainer 18 by welding so as to protrude toward the valve body 6. These second upper protrusion 23 and second lower protrusion 24 loosely hold the upper and lower parts of the inner circumference of the coil spring 19.

[0009] As described above, the upper protrusion 21 and the lower protrusion 22, and the second upper protrusion 23 and the second lower protrusion 24 loosely hold the upper and lower parts of the outer circumference of the coil spring 19, thereby preventing the coil spring 19 from shifting in the vertical direction. In addition, the second upper protrusion 23 and the second lower protrusion 24 loosely hold the upper and lower parts of the inner circumference of the coil spring 19, thereby preventing the coil spring 19 from shifting in the horizontal direction. [Prior art documents] [Patent Documents]

[0010] [Patent Document 1] Japanese Patent Publication No. 2009-275852 [Overview of the project] [Problems that the invention aims to solve]

[0011] However, in the technology described in Patent Document 1 mentioned above, if a relatively soft coil spring with a small spring constant is used, the support of the coil spring 19 may become unstable. That is, in the process of the valve body 6 moving back and forth within the valve chamber 3 while being subjected to fluid pressure, depending on the circumstances, there is a risk that the coil spring 19 may be displaced obliquely with respect to the direction of movement of the valve body 6. In such a case, the repulsive force that the coil spring 19 exerts on the valve body 6 may become uneven, and there is a risk that the check valve may not be able to close properly.

[0012] In this regard, in order to further stabilize the support of the coil spring 19, it is conceivable to set the distance between the upper protrusion 21 and the second upper protrusion 23, and the distance between the lower protrusion 22 and the second lower protrusion 24 to be small, and support the coil spring 19 by sandwiching it in a narrow space. However, in such a case, when performing assembly work in the manufacturing process of the check valve, it is difficult to insert and fit the coil spring 19 into this narrow space, and the assembly work cannot be easily performed.

[0013] Therefore, the purpose of the check valve device according to the present invention is to provide a check valve device that can stably support the biasing means by preventing diagonal displacement of the biasing means, and that is also easy to assemble. [Means for solving the problem]

[0014] The check valve device relating to this application is A main body having an inlet, a valve chamber communicating with the inlet, and an outlet communicating with the valve chamber, wherein a fluid flows through a flow path formed along the inlet, the valve chamber, and the outlet, A valve body means movably disposed in the valve chamber, wherein the valve body means opens the flow path when the fluid flows in the forward direction from the inlet to the outlet, and closes the flow path when the fluid flows in the reverse direction from the outlet to the inlet. A biasing means for biasing the valve body means in the forward or reverse direction, Support means for supporting the biasing means, A check valve device equipped with, The aforementioned support means is base surface, Basic protrusions that protrude from the base surface, An auxiliary projection that protrudes from the base surface and forms a support space between itself and the basic projection, It is equipped with, By positioning the support target portion of the biasing means in the support space, the support means supports the biasing means. The basic projection and the auxiliary projection each have a basic inclined surface and an auxiliary inclined surface formed thereon, respectively, which are inclined to narrow the support space toward the base surface. It is characterized by the following: [Effects of the Invention]

[0015] In the check valve device according to the present invention, the support means supports the biasing means by positioning the part of the biasing means that is to be supported within the support space. The basic projection and the auxiliary projection each have a basic inclined surface and an auxiliary inclined surface, respectively, which are inclined to narrow the support space toward the base surface.

[0016] Therefore, even if the biasing mechanism experiences diagonal displacement, the supported portion of the biasing mechanism is guided to the base surface by both the basic and auxiliary inclined surfaces, allowing the supported portion of the biasing mechanism to be positioned correctly. Thus, by preventing diagonal displacement of the biasing mechanism, the biasing mechanism can be stably supported.

[0017] Furthermore, since the basic inclined surface and the auxiliary inclined surface that are inclined so as to narrow the support space portion are formed, when assembly work is performed in the manufacturing process of the check valve device, the biasing means is guided by the basic inclined surface and the auxiliary inclined surface and is accommodated in the support space portion. Therefore, the assembly work of the check valve device can be easily performed. [Brief Description of the Drawings]

[0018] [Figure 1] It is a cross-sectional view showing a disc-type check valve 1 which is the first embodiment of the check valve device according to the present application, and is a cross-sectional view showing a valve closed state. [Figure 2] It is a front view of the secondary side body 12 of the disc-type check valve 1 shown in FIG. 1 as viewed from the valve chamber 7 side. [Figure 3] It is a cross-sectional view showing the valve open state of the disc-type check valve 1 shown in FIG. 1. [Modes for Carrying Out the Invention]

[0019] [Term Description in Embodiment] Main terms shown in the following embodiments respectively correspond to the following constituent elements of the check valve device according to the present application.

[0020] Disc-type check valve 1···Check valve device Disc valve 2···Valve body means Spring receiving portion 3···Support means Valve chamber 7···Valve chamber portion Valve chamber 7, inflow port 51 and outflow port 52···Flow path Coil spring 10···Biasing means Base end portion 10a···Supported portion Primary side body 11 and secondary side body 12···Main body portion Abutment surface 30···Base surface Outer guide 31···Basic protruding portion Outer tapered surface 31a···Basic inclined surface Inner guide 32···Auxiliary protruding portion Inner tapered surface 32a···Auxiliary inclined surface Inner vertical surface 32b···Contact target portion Support space 35...Support space part Inflow port 51...Inlet part Outlet port 52...Exit part Arrow 91 Direction... Forward Arrow 92 directions...reverse direction Drain, etc. ... fluid

[0021] [First Embodiment] A disc-type check valve 1, which is a first embodiment of the check valve device according to the present invention, will be described with reference to the drawings. This disc-type check valve 1 is installed, for example, in a piping system for steam transfer to prevent backflow of drain (condensed water) generated from steam.

[0022] (Explanation of the configuration of disc-type check valve 1) As shown in Figure 1, the disc-type check valve 1 has a primary body 11 and a secondary body 12, and is constructed with a valve chamber 7 formed inside. The primary body 11 and the secondary body 12 are screw-connected by a threaded portion 13, and the airtightness of the valve chamber 7 is maintained by sandwiching a gasket 15.

[0023] A cylindrical inlet 51 is formed through the primary body 11 and communicates with the valve chamber 7. Piping (not shown) is connected to the outside of the inlet 51, and drain and other substances flow into the valve chamber 7 through the inlet 51 in the direction of arrow 91. A cylindrical outlet 52 is formed through the secondary body 12 coaxially with the inlet 51 and communicates with the valve chamber 7. A discharge pipe (not shown) is connected to the outside of the outlet 52, and drain and other substances are discharged from the valve chamber 7.

[0024] The center line L1 is a virtual line indicating the central axis of the inlet 51 and outlet 52. The inner end face of the primary body 11 that forms the valve chamber 7 functions as the valve seat surface 9. In this embodiment, the inlet 51 side of the disc-type check valve 1 is the primary side, and the outlet 52 side is the secondary side.

[0025] A disc-shaped valve 2 is positioned in the valve chamber 7. A primary valve stem 21 and a secondary valve stem 22, both cylindrical in shape, are fixed to the center of each side of the disc valve 2. The central axes of the disc valve 2, the primary valve stem 21, and the secondary valve stem 22 are aligned with the center line L1. The disc valve 2, the primary valve stem 21, and the secondary valve stem 22 can move freely back and forth in the direction of the center line L1 as a single unit.

[0026] Four primary ribs 11a are fixed to the primary body 11, arranged radially and intersecting at right angles. A cylindrical primary guide tube 11b is provided at the center of these four primary ribs 11a. The primary valve stem 21 is positioned to pass through the primary guide tube 11b.

[0027] Furthermore, as shown in Figure 2, four secondary ribs 12a are fixed to the secondary body 12, arranged radially and intersecting at right angles. A cylindrical secondary guide tube 12b is provided in the center of these four secondary ribs 12a. The secondary valve stem 22 is positioned to pass through the secondary guide tube 12b.

[0028] Furthermore, the inner diameters of the primary guide pipe 11b and the secondary guide pipe 12b are slightly larger than the outer diameters of the primary valve stem 21 and the secondary valve stem 22, respectively, so that the primary valve stem 21 and the secondary valve stem 22 can slide within the primary guide pipe 11b and the secondary guide pipe 12b, respectively. As a result, as described above, the disc valve 2, the primary valve stem 21 and the secondary valve stem 22 are supported within the valve chamber 7 so that they can reciprocate together in the direction of the centerline L1.

[0029] A coil spring 10 is positioned around the secondary valve stem 22 located within the valve chamber 7. The coil spring 10 is attached between the spring receiving portion 3 formed on each of the four secondary ribs 12a and the disc valve 2, constantly biasing the disc valve 2 toward the valve seat surface 9. In this embodiment, the coil spring 10 is, for example, a relatively soft coil spring with a small spring constant.

[0030] As shown in the enlarged view of Figure 1, the spring support portions 3 formed on the four secondary ribs 12a each have an outer guide 31 and an inner guide 32 integrally formed on them. Each outer guide 31 is located further out from the center line L1, while the inner guide 32 is located closer to the center line L1. A support space 35, which is a spatial region, is formed between the outer guide 31 and the inner guide 32.

[0031] The base end portion of the coil spring 10, the coil spring end portion 10a, is fitted into this support space 35. The portion of the secondary rib 12a that the coil spring end portion 10a contacts and receives a repulsive force is the contact surface 30.

[0032] The outer guide 31, which is continuous with the contact surface 30, has an outer vertical surface 31b that rises perpendicularly to the contact surface 30. An outer tapered surface 31a is formed continuous with this outer vertical surface 31b. The inner guide 32, which is continuous with the contact surface 30, has an inner vertical surface 32b that rises perpendicularly to the contact surface 30, and an inner tapered surface 32a is formed continuous with this inner vertical surface 32b.

[0033] As shown in the enlarged view of Figure 1, the width and length of the contact surface 30 are approximately the same as the rise lengths of the outer vertical surface 31b and the inner vertical surface 32b, and are longer than the outer diameter of the linear material of the coil spring 10. This ensures that the coil spring end portion 10a of the coil spring 10 fits securely within the roughly square space defined by the contact surface 30, the outer vertical surface 31b, and the inner vertical surface 32b.

[0034] Furthermore, the inner diameter of the coil spring 10 is formed to be slightly shorter than the outer diameter G32 (straight length passing through the center line L1) of the circle passing through the inner vertical surfaces 32b of each of the four secondary ribs 12a shown in Figure 2. Therefore, when the coil spring end 10a of the coil spring 10 is placed in the support space 35, the coil spring end 10a is spread slightly outward, thereby supporting the four inner vertical surfaces 32b in a state of pressure directed inward.

[0035] The outer tapered surface 31a and the inner tapered surface 32a are inclined such that the support space 35 widens in the direction away from the contact surface 30. The outer inclination angle 31c of the outer tapered surface 31a is set to be greater inclination than the inner inclination angle 32c of the inner tapered surface 32a. In this embodiment, for example, the outer inclination angle 31c is approximately 25 degrees, and the inner inclination angle 32c is approximately 20 degrees. In addition, the protruding length 32d of the inner guide 32 protruding from the contact surface 30 is set to be shorter than the protruding length 31d of the outer guide 31 protruding from the contact surface 30.

[0036] By the way, when assembling the disc-type check valve 1 during the manufacturing process, the coil spring 10 is attached to the secondary body 12, the secondary valve stem 22 of the disc valve 2 is inserted into the secondary guide tube 12b, and then the primary body 11 is screwed onto the secondary body 12 with the threaded portion 13, with the gasket 15 in between.

[0037] In this process, it is necessary to insert the coil spring end 10a of the coil spring 10 into the support spaces 35 formed in four locations on the secondary body 12 and bring it to rest on the contact surface 30 (Figure 1). However, since the support spaces 35 are narrow and there are four of them, it is not always easy to insert the coil spring end 10a into all four support spaces 35 simultaneously.

[0038] In this respect, in the disc-type check valve 1 of this embodiment, since an outer tapered surface 31a and an inner tapered surface 32a are formed on both sides of the support space 35, the coil spring end 10a is guided by these outer tapered surface 31a and inner tapered surface 32a into the support space 35 and can be brought to rest on the contact surface 30. Therefore, the assembly of the disc-type check valve 1 can be performed easily and reliably.

[0039] Furthermore, as mentioned above, the outer inclination angle 31c of the outer tapered surface 31a is approximately 25 degrees, and the inner inclination angle 32c of the inner tapered surface 32a is approximately 20 degrees, meaning that the outer inclination angle 31c is steeper than the inner inclination angle 32c. Moreover, as mentioned above, the protruding length 32d of the inner guide 32 is shorter than the protruding length 31d of the outer guide 31, with the protruding length 31d of the outer guide 31 being longer.

[0040] Therefore, when inserting the coil spring end 10a into the support space 35, the coil spring end 10a first contacts the outer guide 31, which protrudes longer. However, because the outer inclination angle 31c is approximately 25 degrees, the coil spring end 10a is smoothly guided and inserted into the support space 35. As a result, the assembly of the disc-type check valve 1 can be performed easily and reliably.

[0041] Furthermore, after the coil spring end 10a is inserted into the support space 35 and lands on the contact surface 30, the inner tapered surface 32a with an inner inclination angle 32c that is closer to vertical prevents the coil spring end 10a from detaching from the support space 35, thus allowing the coil spring 10 to be supported more stably.

[0042] Furthermore, as mentioned above, the inner diameter of the coil spring 10 is formed to be slightly shorter than the distance G32 between the inner vertical surfaces 32b of each of the four secondary ribs 12a. When the coil spring end 10a of the coil spring 10 is placed in the support space 35, it is supported with the four inner vertical surfaces 32b pressed inward. As a result, after inserting the coil spring end 10a into the support space 35, the mounting position of the coil spring 10 is stable, making subsequent assembly work easier.

[0043] Furthermore, as mentioned above, the protruding length 32d of the inner guide 32 is shorter than the protruding length 31d of the outer guide 31. Therefore, when inserting the coil spring end 10a into the four support spaces 35, it is possible to avoid the inner circumferential surface of the coil spring 10 catching on the protruding tip of the inner guide 32. Consequently, the assembly of the disc-type check valve 1 can be performed more easily and reliably.

[0044] In this embodiment, as described above, an outer vertical surface 31b and an inner vertical surface 32b are formed that rise perpendicularly to the contact surface 30, and an outer tapered surface 31a and an inner tapered surface 32a are continuous to these, respectively. However, in other embodiments, the outer vertical surface 31b and inner vertical surface 32b may not be provided, and the outer tapered surface 31a and inner tapered surface 32a may be directly continuous to the contact surface 30.

[0045] Even with this configuration, especially for the relatively soft coil spring 10 with a small spring constant, the coil spring end 10a is guided by the outer tapered surface 31a and the inner tapered surface 32a into the support space 35 and lands on the contact surface 30. This makes the assembly of the disc-type check valve 1 easy and reliable. Furthermore, because the coil spring end 10a is guided by the outer tapered surface 31a and the inner tapered surface 32a and lands on the contact surface 30, displacement of the coil spring 10 is prevented after the assembly of the disc-type check valve 1, and the coil spring 10 can be stably supported.

[0046] (Explanation of the operation of disc-type check valve 1) Next, the operation of the disc-type check valve 1 will be explained. When a fluid such as drain flows into the disc-type check valve 1 from the inlet 51 in the direction of arrow 91, and the primary pressure becomes greater than the secondary pressure, the primary disc surface of the disc valve 2 in the valve chamber 7 receives the inflow pressure, compresses the coil spring 10, and moves away from the valve seat surface 9, opening the valve as shown in Figure 3.

[0047] At this time, the primary guide pipe 11b and the secondary guide pipe 12b support the primary valve stem 21 and the secondary valve stem 22, respectively, and guide the movement of the disc valve 2, so that the disc valve 2 moves in parallel without any diagonal displacement.

[0048] As the disc valve 2 moves and separates from the valve seat surface 9, the disc-type check valve 1 opens, and the incoming drain and other fluids pass around the disc valve 2, through the four secondary ribs 12a, and are discharged from the outlet 52 in the direction of arrow 91.

[0049] In contrast, if drain or other fluids flow back in from the outlet 52 in the direction of arrow 92, creating a back pressure where the primary pressure is lower than the secondary pressure, this backflow pressurizes the secondary disc surface of the disc valve 2. Then, due to the fluid pressure of this backflow and the repulsive force of the coil spring 10, the disc valve 2 moves and seats on the valve seat surface 9, closing the valve (Figure 1). This blocks the backflow of drain or other fluids.

[0050] As described above, the coil spring end 10a of the coil spring 10 is fitted into and supported in the support space 35 of the spring receiving portion 3 formed on each of the four secondary ribs 12a, and the outer guide 31 and inner guide 32 located on both sides of the support space 35 have an outer tapered surface 31a and an inner tapered surface 32a, respectively.

[0051] Therefore, even if the coil spring 10 is displaced obliquely due to the reciprocating movement of the disc valve 2, especially for coil springs 10 with a small spring constant and relatively softness, the coil spring end 10a is smoothly guided along the outer tapered surface 31a or the inner tapered surface 32a within the support space 35 and reliably returns to the position where it contacts the contact surface 30. Thus, by preventing the coil spring 10 from being displaced obliquely, the coil spring 10 can be stably supported.

[0052] Furthermore, when the coil spring end 10a is in contact with the contact surface 30, the coil spring end 10a is covered by the outer vertical surface 31b and the inner vertical surface 32b, which are continuous with the contact surface 30. Therefore, once the coil spring end 10a has come into contact with and settled against the contact surface 30 of the spring receiving portion 3, it will not easily separate from the contact surface 30, and the coil spring 10 can be supported more reliably and stably.

[0053] Furthermore, as mentioned above, the protruding length 32d of the inner guide 32 protruding from the contact surface 30 is shorter than the protruding length 31d of the outer guide 31 protruding from the contact surface 30. If the protruding length 32d of the inner guide 32 were longer than the protruding length 31d of the outer guide 31, when the coil spring 10 experiences a slight diagonal displacement, the inner circumference of the coil spring 10 may catch on the inner guide 32, interfering with the repulsive force of the coil spring 10 and potentially resulting in insufficient biasing of the disc valve 2. However, in this embodiment, since the protruding length 32d of the inner guide 32 is shorter than the protruding length 31d of the outer guide 31, it is possible to avoid the situation where the inside of the coil spring 10 catches on the inner guide 32.

[0054] [Other embodiments] In the embodiments described above, specific examples were given for each of the following: the check valve device, the inlet, the valve chamber, the outlet, the main body, the flow path, the fluid, the valve body means, the forward direction, the reverse direction, the biasing means, the support means, the base surface, the basic projection, the auxiliary projection, the support space, the basic inclined surface, the auxiliary inclined surface, the end of the coil spring, and the contact target. However, these are merely examples, and different configurations can be adopted.

[0055] For example, in the above-described embodiment, a disc-type check valve 1 was exemplified as the check valve device according to the present invention, but it can also be applied to other types of check valves as long as they perform closing or opening by the movement of a valve body and are equipped with a biasing means such as a coil spring. For example, the check valve device according to the present invention can be applied to check valves of other structures, such as swing-type check valves and lift-type check valves.

[0056] Furthermore, although the aforementioned embodiment exemplified a disc valve 2 as the valve body means, other shapes and structures can be used as long as they open and close the flow path (valve chamber 7, inlet 51, outlet 52, etc.).

[0057] Furthermore, although a coil spring 10 was exemplified as the biasing means in the above-described embodiment, the invention is not limited to this, and other configurations may be used as long as they bias the valve body means (disk valve 2, etc.) in the forward or reverse direction. In addition, although an example was shown in which the coil spring 10 biases the disc valve 2 in the reverse direction (direction of arrow 92, etc.), the check valve device according to the present invention may also be applied to a check valve equipped with a biasing means (coil spring 10, etc.) that biases in the forward direction (direction of arrow 91, etc.).

[0058] Furthermore, in the above-described embodiment, the spring receiving portion 3 was exemplified as the support means, the contact surface 30 as the base surface, the outer guide 31 as the basic projection, the inner guide 32 as the auxiliary projection, and the support space 35 as the support space portion. However, other shapes and structures can be used as long as they are configured to support the biasing means (coil spring 10).

[0059] Furthermore, in the above-described embodiment, an outer tapered surface 31a with an outer inclination angle 31c of approximately 25 degrees was exemplified as the basic inclined surface, and an inner tapered surface 32a with an inner inclination angle 32c of approximately 20 degrees was exemplified as the auxiliary inclined surface. However, different angles can also be adopted for each.

[0060] Furthermore, the embodiments described above can be arbitrarily combined to create new embodiments. [Explanation of Symbols]

[0061] 1: Disc-type check valve 2: Disc valve 3: Spring seat 7: Valve chamber 10: Coil spring 10a: Coil spring end 11: Primary body 12: Secondary body 30: Contact surface 31: Outer guide 31a: Outer tapered surface 32: Inner guide 32a: Inner tapered surface 32b: Inner vertical surface; 35: Support space; 51: Inlet; 52: Outlet

Claims

1. A main body having an inlet, a valve chamber communicating with the inlet, and an outlet communicating with the valve chamber, wherein a fluid flows through a flow path formed along the inlet, the valve chamber, and the outlet, A valve body means movably disposed in the valve chamber, wherein the valve body means opens the flow path when the fluid flows in the forward direction from the inlet to the outlet, and closes the flow path when the fluid flows in the reverse direction from the outlet to the inlet. A biasing means for biasing the valve body means in the forward or reverse direction, Support means for supporting the biasing means, A check valve device equipped with, The aforementioned support means is base surface, Basic protrusions that protrude from the base surface, An auxiliary projection that protrudes from the base surface and forms a support space between itself and the basic projection, It is equipped with, By positioning the support target portion of the biasing means in the support space, the support means supports the biasing means. The basic projection and the auxiliary projection each have a basic inclined surface and an auxiliary inclined surface formed thereon, respectively, which are inclined to narrow the support space toward the base surface. A check valve device characterized by the following features.

2. In the check valve device according to claim 1, The biasing means is a coil spring formed in a coil shape, and the supported portion is the end of the coil spring. A check valve device characterized by the following features.

3. In the check valve device according to claim 2, The basic protrusion is located on the outside of the coil spring. The auxiliary projection is located inside the coil spring. The auxiliary projection has a shorter projection length than the basic projection. A check valve device characterized by the following features.

4. In the check valve device according to claim 2, The aforementioned basic protrusion is located on the outside of the coil spring, The auxiliary projection is located inside the coil spring. The aforementioned basic inclined surface has a greater degree of inclination than the aforementioned auxiliary inclined surface. A check valve device characterized by the following features.

5. In the check valve device according to claim 2, The basic protrusion is located on the outside of the coil spring. The auxiliary projection is located inside the coil spring. The inner circumferential surface of the end of the coil spring, which is the part to be supported, is in contact with the part to be contacted by the auxiliary projection, and the inner diameter of the end of the coil spring is smaller than the outer diameter of the part to be contacted. A check valve device characterized by the following features.

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