Patent Application
20250172215
The present disclosure relates to check valves.
The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
A check valve for inhibiting backflow of fluid usually involves a flow path member having a fluid passage and a valve element disposed in the fluid passage. The valve element is disposed in the fluid passage so as to be displaceable between a closed position where the valve element closes the fluid passage and an open position where the valve element opens the fluid passage. In addition, the valve element is urged upstream by a spring. In the closed position, the valve element is pressed against a valve seat surface of the flow path member by the urging force of the spring, thereby being sealingly engaged with the valve seat surface. The valve element is also pressed against the valve seat surface by the fluid pressure applied from the downstream side. In check valves used for a fluid of relatively low pressure, a seal ring formed of an elastic material such as rubber is attached to the valve element so as to be sandwiched between the valve element and the valve seat surface, thereby enabling the area between the valve element and the valve seat surface to be sealed with a relatively small pressing force. However, check valves used for high-pressure fluids involve the possibility that the seal ring may be detached or broken by the strong force of the high-pressure fluid, and therefore often adopt a so-called a metal-to-metal sealing structure, in which the seal ring is not used; instead, a valve element and a valve seat surface which are formed of metallic materials of high rigidity are directly abutted against each other (for example, Patent Literature 1).
This section provides a general summary of the disclosure and is not a comprehensive disclosure of its full scope or all of its features.
The metal-to-metal sealing structure, in which metallic materials of high rigidity are directly abutted against each other, has high pressure resistance but the valve element and the valve seat surface are desired to be formed with high accuracy in order to achieve satisfactory sealability because the valve element and the valve seat surface are not easily elastically deformable when abutted against each other. In addition, relatively loud noise is likely to occur when the valve element collides with the valve seat surface. When chattering occurs, in particular, the noise may cause issues. On the other hand, if the valve element is formed of a material of low rigidity (e.g. resin material), when abutted against the valve seat surface, the valve element is easily elastically deformable following the shape of the valve seat surface, so that high sealability can be achieved relatively easily. This also may reduce noise occurring when the valve element collides with the valve seat surface. However, because the valve element is formed of a low-rigidity material, there is a high risk that the valve element may be greatly deformed when excessive fluid pressure is applied thereto from the downstream side in a valve closed state; under certain circumstances, the valve element may be partly broken and scattered in the flow path.
Accordingly, it is an object of the present disclosure to provide a check valve configured to provide high sealability and to inhibit breakage and scattering of the valve element even when high fluid pressure is applied thereto.
That is, the present disclosure provides a check valve including: a flow path member having an upstream opening, a downstream opening, and an inner peripheral surface defining a fluid passage extending from the upstream opening to the downstream opening, the inner peripheral surface having formed thereon a valve seat surface and a locking surface located upstream and radially inward of the valve seat surface; and a valve element disposed in the fluid passage so as to be displaceable between a closed position where the valve element is engaged with the valve seat surface to close the fluid passage and an open position where the valve element is separated from the valve seat surface toward a downstream side to open the fluid passage. The valve element is formed of a material with lower rigidity than at least portions of the flow path member where the valve seat surface and the locking surface are formed, so that when the valve element is displaced, by receiving a force toward an upstream side, from the closed position to a position further upstream of the closed position while deforming a portion of the valve element that is engaged with the valve seat surface, the valve element that has deformed is engaged with and supported by the locking surface.
In the above-described check valve, even when a portion of the valve element that is abutted against the valve seat surface is deformed by the application of a large force, for example, by excessive fluid pressure applied from the downstream side to the valve element in the closed position, the valve element is supported relative to the flow path member at the locking surface. Therefore, it is possible to inhibit the valve element from being further displaced toward the upstream side while being deformed. In addition, because the deformed portion of the valve element engages the locking surface, it is possible to inhibit the deformed portion from being broken and scattered like being torn off by the surrounding pressure. On the other hand, it is possible to form the valve element of a material of relatively low rigidity while ensuring a minimal level of safety and hence possible to easily achieve high sealability between the valve element and the valve seat surface. In addition, noise occurring when the valve element collides with the valve seat surface can be reduced as compared with a case where the valve element is formed of a high-rigidity metal.
The valve seat surface and the locking surface may be inclined radially inward toward the upstream side, and a transition surface parallel to the longitudinal axis of the fluid passage may be formed between the valve seat surface and the locking surface.
Furthermore, the valve element may be formed of a resin material, and the flow path member may be formed of a metallic material.
Forms of a check valve according to the present disclosure will be explained below based on the accompanying drawings.
Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
In order that the disclosure may be well understood, there will now be described various forms thereof, given by way of example, reference being made to the accompanying drawings, in which:
The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.
The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.
As shown in
The inner peripheral surface 12 of the flow path member 14 includes a valve seat surface 30, a locking surface 32 located upstream and radially inward of the valve seat surface 30, and a transition surface 34 extending parallel to the longitudinal axis L of the flow path member 14 between the valve seat surface 30 and the locking surface 32. The valve seat surface 30 and the locking surface 32 are inclined radially inward toward the upstream side.
The valve element 16 has an abutting portion 36 engageable with the valve seat surface 30, a forward end face 38 extending radially inward from the abutting portion 36, and a projecting portion 40 projecting upstream from the forward end face 38. The forward end face 38 extends to a position slightly radially inward of the locking surface 32 of the flow path member 14. The valve element 16 is urged upstream by the spring 24, so that the abutting portion 36 of the valve element 16 is pressed against the valve seat surface 30 of the flow path member 14. Thus, the abutting portion 36 of the valve element 16 sealingly engages the valve seat surface 30, thereby closing the fluid passage 10. It should be noted that, in this example, the flow path member 14 is formed of a metallic material (e.g. stainless steel), and the valve element 16 is formed of a resin material (e.g. high-strength resin). Because the valve element 16 is formed of a resin material with lower rigidity than the metallic material, when pressed against the valve seat surface 30, the valve element 16 is appropriately elastically deformed following the shape of the valve seat surface 30, thereby providing high sealability between the valve element 16 and the valve seat surface 30.
When the fluid pressure at the upstream opening 18 side is less than the resultant force of the urging force of the spring 24 and the fluid pressure at the downstream opening 20 side, the valve element 16 is pressed against the valve seat surface 30 of the flow path member 14 by the urging force of the spring 24 and the fluid pressure applied from the downstream opening 20 side, thereby closing the fluid passage 10. That is, the valve element 16 assumes a closed position (
When the fluid pressure at the upstream opening 18 side drops due, for example, to the suspension of the supply of fluid from the upstream opening 18, the valve element 16 is pushed toward the upstream side by the urging force of the spring 24 and the fluid pressure applied from the downstream opening 20 side. The valve element 17 returns to the closed position shown in
Thus, with the check valve 1, high sealability can be achieved relatively easily by forming the valve element 16 of a material with relatively low rigidity and high elasticity, and it is also possible to reduce noise occurring when the valve element 16 collides as compared with a case where the valve element is formed of a high-rigidity metallic material. In addition to these advantageous features, the following advantage is obtained. Even if the valve element 16 is greatly deformed by an excessive fluid pressure applied from the downstream side in a valve closed state, the deformed valve element 16 is supported by the locking surface 32, thereby making it possible to inhibit the valve element 16 from being further deformed and broken. Thus, the valve element 16 can be inhibited from being scattered in the fluid passage 10.
Although some examples of the present disclosure have been explained above, the present disclosure is not limited to these examples. For example, the materials constituting the flow path member and the valve element are not limited to the above-described metallic and resin materials, respectively, but other metallic and resin materials may be used to constitute the flow path member and the valve element, respectively, taking into account the conditions of use, e.g. type, pressure and temperature of the fluid. In addition, the flow path member does not necessarily need to be formed of a metallic material. If no very high-pressure fluid flows through the flow path member, for example, the flow path member may be formed of a resin material of relatively high rigidity, and the valve element may be formed of another resin or rubber material with lower rigidity than the resin material constituting the flow path member. In other words, as a material forming each member, an optimal material may be appropriately selected according to the conditions of use, provided that the valve element is formed of a material with lower rigidity than the flow path member. Furthermore, the whole of the flow path member does not necessarily need to be formed of a material with higher rigidity than the valve element, but at least portions of the flow path member where the locking surface and the locking surface are formed are formed of the above-described material. The locking surface does not necessarily need to be inclined relative to the longitudinal axis. It may instead be perpendicular to the longitudinal axis. The check valve according to the present disclosure is applicable to a variety of fluids, for example, gases such as oxygen and hydrogen, liquids such as water and chemicals, or gas-liquid mixed fluid.
Unless otherwise expressly indicated herein, all numerical values indicating mechanical/thermal properties, compositional percentages, dimensions and/or tolerances, or other characteristics are to be understood as modified by the word “about” or “approximately” in describing the scope of the present disclosure. This modification is desired for various reasons including industrial practice, material, manufacturing, and assembly tolerances, and testing capability.
As used herein, the phrase at least one of A, B, and C should be construed to mean a logical (A OR B OR C), using a non-exclusive logical OR, and should not be construed to mean “at least one of A, at least one of B, and at least one of C.”
The description of the disclosure is merely exemplary in nature and, thus, variations that do not depart from the substance of the disclosure are intended to be within the scope of the disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022-117870 | Jul 2022 | JP | national |
This application is a continuation of International Application No. PCT/JP2023/023037, filed on Jun. 22, 2023, which claims priority to and the benefit of Japanese Patent Application No. 2022-117870, filed on Jul. 25, 2022. The disclosures of the above applications are incorporated herein by reference in their entireties.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2023/023037 | Jun 2023 | WO |
| Child | 19036312 | US |
