Check valve with color change and pressure sensing

Abstract

A check valve includes an upper housing defining an inlet of the check valve and a lower housing having a support portion and defining an outlet of the check valve. The check valve further includes a chamber interposed between and defined by the upper housing and the lower housing for fluidly connecting the inlet and the outlet, and a flexible diaphragm mounted in the chamber. The flexible diaphragm selectively permits fluid flow in a first direction and prevents fluid backflow in a second direction opposite the first direction. The flexible diaphragm includes a color-changing material and exhibits a color change when the flexible diaphragm is seated on the support portion and is flexed due to a force of fluid flowing in the first direction.

Description

TECHNICAL FIELD

[0001] The present disclosure relates generally to check valves, and more particularly to a valve member of a check valve that is capable of changing color to visually indicate patency when subjected to pressure from fluid flow. BACKGROUND

[0002] Infusion IV (intravenous) sets are commonly used in infusion therapy in order to deliver a medication from a pre-filled container, such as an IV bottle or bag containing the desired medication, to a patient. Typically, an IV tubing is coupled to a catheter and inserted into a local area to be treated.

[0003] A patient is typically injected with an IV solution that is initially disposed in an IV bottle or bag and dripped through an IV line into a vein of the patient. Typically, an injection port is disposed along the IV line and is adapted to work with a syringe to allow an injection to be added to the IV solution. A check valve is also typically included in the IV line to allow fluid flow only in the direction of the patient. This ensures that the injection flows downstream toward the patient and not upstream toward the IV container.

[0004] In order to check the patency of a conventional check valve, the IV line must currently be opened in order to access and check the check valve.

[0005] The description provided in the background section should not be taken as an admission that any of the information provided in the background section is prior art to the present disclosure. The background section can include information obtained from sources believed to be reliable and are not necessarily statements of fact or assumptions of fact. SUMMARY

[0006] According to various embodiments of the present disclosure, a check valve can include an upper housing defining an inlet of the check valve; a lower housing including a support portion and defining an outlet of the check valve; and a chamber interposed between and defined by the upper housing and the lower housing for fluidly connecting the inlet and the outlet. The check valve can further include a flexible diaphragm mounted in the chamber to selectively allow fluid flow in a first direction and prevent fluid backflow in a second direction opposite the first direction. The flexible diaphragm can include a color-changing material, wherein the flexible diaphragm exhibits a color change when the flexible diaphragm is seated on the support portion and is flexed due to a force of the fluid flowing in the first direction.

[0007] According to various aspects of the present disclosure, a check valve can include a valve chamber including an inlet port at an inlet end, an outlet port at an outlet end, and an interior surface of a roof and a convexly shaped sidewall defining the chamber. The check valve can further include a flexible diaphragm supported within the valve chamber. The flexible diaphragm can include a multi-layered transparent material that exhibits a color change when the flexible diaphragm is seated in the valve chamber and is flexed due to the force of fluid flowing from the inlet port to the outlet port.

[0008] It should be understood that other configurations of the subject technology will become readily apparent to those skilled in the art from the following detailed description, wherein various configurations of the subject technology are shown and described by way of illustration. As will be realized, the subject technology is capable of other and different configurations and its several details are capable of modification in various other respects, all without departing from the scope of the subject technology. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not as restrictive. BRIEF DESCRIPTION OF DRAWINGS

[0009] The following drawings are included to illustrate certain aspects of the embodiments and are not intended to be exclusive or limiting of the subject technology. The disclosed subject matter can take form in many different arrangements, combinations and / or permutations of parts as will be appreciated by those skilled in the art from the following detailed description.

[0010] Figure 1 An IV extension device including a check valve is shown in accordance with some embodiments of the present disclosure.

[0011] Figure 2 A cross-sectional view of a check valve in an open state is shown in accordance with some embodiments of the present disclosure.

[0012] Figure 3 A cross-sectional view of a check valve coupled to a male luer fitting is shown in accordance with some embodiments of the present disclosure.

[0013] Figure 4 A cross-sectional view of a check valve of Figure 3 along line 4-4 is shown in accordance with some embodiments of the present disclosure.

[0014] Figure 5 A cross-sectional view of a check valve in a closed state is shown in accordance with some embodiments of the present disclosure. DETAILED DESCRIPTION

[0015] The detailed description set forth below describes various configurations of the subject technology and is not intended to represent the only configurations in which the subject technology can be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of the subject technology. Accordingly, the descriptions can provide details regarding certain aspects of some examples that can be practiced in other examples. However, it will be apparent to those skilled in the art that the subject technology can be practiced without these specific details. In some instances, well-known structures and components are shown in block diagram form, rather than in detail, in order to avoid obscuring the concepts of the subject technology.

[0016] It is understood that the present disclosure includes examples of the subject technology and does not limit the scope of the appended claims. Various aspects of the subject technology will now be disclosed, in accordance with specific but non-limiting examples. The various embodiments described in this disclosure can be implemented in different ways and variations and according to desired applications or implementations.

[0017] The present specification generally relates to check valves, and more particularly, for example but without limitation, to check valves that are capable of changing color when subjected to pressure from a fluid flow to visually indicate patency.

[0018] According to some embodiments, a check valve includes an upper housing defining an inlet of the check valve; a lower housing defining an outlet of the check valve; and a chamber interposed between and defined by the upper housing and the lower housing for fluidly connecting the inlet and the outlet. A flexible diaphragm can be mounted in the chamber to selectively allow fluid flow from the inlet to the outlet and prevent fluid backflow (reverse flow) from the outlet to the inlet.

[0019] In some embodiments, the flexible diaphragm can be in the form of a circular disc or any other circular plate, and can be formed of a color-changing material. The flexible diaphragm can change color when it is placed on a support portion of the lower housing and is bent or flexed due to pressure of fluid flowing in the direction from the inlet to the outlet. Structurally, the flexible diaphragm can be formed of a plurality of stacked layers of transparent material. When the flexible diaphragm is exposed to upstream pressure (i.e., pressure exerted by fluid flowing from the inlet to the outlet), the flexible diaphragm bends, flexes, or otherwise deforms such that light is reflected from each interface between adjacent layers of the flexible diaphragm. The reflected light produces a color in the visible spectrum on the flexible diaphragm, which a user / caregiver can observe as an indication of fluid flow, thereby indicating patency of the check valve.

[0020] In some embodiments, the upper housing includes an interior surface defining a sidewall of the chamber. The sidewall can have a convex shape that acts as a magnifying lens and allows the color change of the flexible diaphragm to be magnified and more easily visible.

[0021] Advantageously, due to the structure of the upper housing forming a convex shape of the inner wall of the magnifying lens, the color change of the flexible diaphragm can be easily seen from the outside without having to open the fluid line. The color change indicates the patency of the check valve and can confirm to the user or caregiver that fluid is actually flowing through the check valve as intended. Further advantageously, the user or caregiver can confirm that there is net upstream pressure (and thus indicating the presence of flow through the check valve) by simply observing the visual color change of the flexible diaphragm. Thus, there is no longer a need for a separate pressure sensor to confirm fluid flow.

[0022] Figure 1 An IV extension set including a check valve 100 is shown in accordance with some embodiments of the present disclosure. As shown, the IV set 1 includes a primary fluid system 11 and an auxiliary fluid system 25. An IV pump (not shown) receives fluid from the primary fluid system 11 and the auxiliary fluid system 25 via a primary IV line 5 and can control and dispense fluid from the primary and auxiliary fluid systems to a patient 50.

[0023] In some embodiments, the primary fluid system 11 can include a primary fluid source, such as a primary fluid bag 10, which can include or contain a saline solution or other medical fluid or medication to be administered to the patient 50. As shown, the primary IV line 5 transports primary fluid from the drip chamber 13 to the check valve 100. As will be further described with reference to the following figures, the check valve 100 can be disposed in the primary IV line 5 and allow fluid to flow from the primary fluid bag 10 to the IV pump (not shown) while preventing reverse flow (backflow) of fluid from the auxiliary fluid system 25 toward the primary fluid bag 10. According to some embodiments, the auxiliary fluid system 25 includes an auxiliary fluid source, such as an auxiliary fluid bag 20, which can contain a medication or other auxiliary fluid to be supplied to the patient 50 for treatment. As shown, the IV set 1 can further include an auxiliary IV line 7 that transports flow from the drip chamber 22 to the check valve 100.

[0024] Figure 2 A cross-sectional view of a check valve in an open state is shown in accordance with some embodiments of the present disclosure. Referring to Figure 2The check valve 100 may include a body 101 extending axially along a central longitudinal axis X. In some embodiments, the body 101 may be formed of a chemically resistant material that may have amplifying properties. The body 101 may be formed of a material capable of providing excellent light transmittance and transparency. For example, in some embodiments, the body material may be formed of an acrylic polymer. The body 101 may be a generally cylindrical (or tubular) structure and may include an upper housing 10 and a lower housing 15. The upper housing 10 may include a first end portion 12 and an axially opposed second end portion 14. As shown, the radial extension length of the upper housing 10 at the second end portion 14 may be greater than its radial extension length at the first end portion 12. The lower housing 15 may include an upstream inner surface 16, and the second end portion 14 and the upstream inner surface 16 of the lower housing 15 may be in axial contact with each other to collectively form a chamber 30 of the check valve 100.

[0025] In some embodiments, the upper housing 10 may include an inlet 20 of the check valve 100 at a first end 12, and the lower housing 15 may include an outlet 25 of the check valve 100. The body 101 may define an internal flow passage 18 extending axially between the inlet 20 and the outlet 25 and in fluid communication with both the inlet and outlet. As understood, the check valve 100 may allow fluid to flow from the inlet 20 to the outlet 25 (e.g., Figure 2 (as indicated by the arrow in the image), and minimize or otherwise restrict the fluid flow from outlet 25 to inlet 20 (e.g., as shown by the arrow in the image). Figure 5 (As indicated by the arrow in the figure). As shown, the upper housing 10 and the lower housing 15 can define a chamber 30 for fluidly connecting the inlet 20 and the outlet 25.

[0026] Figure 3 A cross-sectional view of a check valve connected to a male Luer joint according to some embodiments of the present disclosure is shown. Figure 4 Some embodiments according to this disclosure are shown. Figure 3 The check valve is shown in a cross-sectional view along line 4-4. Depending on the intended purpose, the check valve 100 of the various embodiments described herein can be positioned at different locations on the IV device 1. For example, in some embodiments, the check valve 100 can be positioned below the infusion chamber 13 to prevent any potential backflow into the main IV line 5. In some embodiments, such as Figure 3 As shown, the check valve 100 can be integrated into the connector or otherwise connected to the connector, such as the male Luer connector 23 at the end of the IV device closer to the patient 50. When connected to connector 23, the check valve 100 can be used to prevent the patient's blood from flowing back into the IV device 1.

[0027] In the illustrated embodiment, a flexible diaphragm 35 can be installed in the chamber 30 to selectively allow fluid flow from the inlet 20 to the outlet 25 and prevent fluid backflow (reverse flow) from the outlet 25 to the inlet 20.

[0028] According to some embodiments, the flexible diaphragm 35 can be in the form of a circular disc or any other circular plate. As illustrated, the flexible diaphragm 35 can be installed on the support portion 28 of the lower housing 14. In particular, the support portion 28 can include a central aperture 44 and a plurality of axially extending slots 46 through which fluid flowing from the inlet 20 into the cavity 30 can enter the outlet 25 in the open state of the check valve 100.

[0029] As illustrated, the flexible diaphragm 35 can be formed of a color changing material. As referred to herein, a color changing material is defined as a material that is capable of reflecting light to present a bright color in the visible spectrum when subjected to an axial load. Thus, when the flexible diaphragm 35 is seated on the support portion 28 and is bent due to the force of fluid flowing in the direction from the inlet 20 to the outlet 25, the flexible diaphragm 35 changes color or otherwise presents a color. In particular, in some embodiments, the flexible diaphragm 35 can be formed of multiple layers of transparent material. For example, the flexible diaphragm 35 can be formed of multiple thin layers of transparent material that can be periodically stacked to form the disc-shaped flexible diaphragm 35. In some embodiments, the thickness of each layer of transparent material within the disc-shaped flexible diaphragm can be on the order of a few hundred nanometers. In some embodiments, the transparent material can be a transparent rubber material or any other similar material that is capable of bending or otherwise deforming under the action of a load.

[0030] In some embodiments, the flexible diaphragm 35 can be formed of a resistive pressure sensing material having a hollow sphere microstructure, such as but not limited to an elastomeric microstructured conductive polymer thin film material.

[0031] In some embodiments, the flexible diaphragm 35 can be formed of a tactile pressure indicating sensor film. In other embodiments, the flexible diaphragm 35 can be formed of a material having hollow spheres in its structure, where the hollow spheres can be pressed together under pressure, causing the flexible diaphragm 35 to change color.

[0032] In some embodiments, the upper housing 10 includes an interior surface having a first portion that defines a top plate 40 of the chamber 30 and a second portion that defines a sidewall 42 of the chamber. As shown, the portion of the interior surface that defines the sidewall 42 can have a convex shape. Additionally, in some embodiments, the sidewall 42 is formed of a transparent material to allow for visual observation of the color change. Advantageously, the convex shape of the sidewall 42 acts as a magnifying lens and allows the color change of the flexible diaphragm 35 to be magnified and more easily observed.

[0033] In operation, when the flexible diaphragm 35 formed of multiple transparent layers is exposed to upstream fluid pressure (i.e., pressure exerted by fluid flowing from the inlet 20 to the outlet 25), the flexible diaphragm 35 can bend, flex, or otherwise deform such that light is reflected from each interface between adjacent layers of the flexible diaphragm. The reflected light produces a color in the visible spectrum on the flexible diaphragm 35, which can depend on the geometric properties and material composition of the transparent layers of the flexible diaphragm 35. For example, for layers of uniform thickness, light reflected from the interfaces between adjacent layers of the flexible diaphragm 35 can interact to enhance some colors in the visible spectrum, such as red, while reducing the brightness of other colors. Thus, when bent due to upstream fluid pressure, the flexible diaphragm 35 formed of transparent layers can appear or otherwise exhibit a particular color depending on the thickness of the layers within the flexible diaphragm 35.

[0034] According to various embodiments, the flexible diaphragm 35 can be formed of pressure-sensing material. For example, the flexible diaphragm 35 can be made of a plurality of layered, pressure-sensing photonic fibers such that, when subjected to upstream pressure, for a particular desired pressure, the fibers of the flexible diaphragm 35 can reflect an easily distinguishable color. To this end, the flexible diaphragm 35 can be designed such that, when fluid flow from the inlet port to the outlet port exerts pressure normal to the flexible diaphragm (the pressure being greater than or equal to a predetermined threshold pressure), the flexible diaphragm changes color.

[0035] Accordingly, various embodiments of the present disclosure provide a check valve 100 having a flexible diaphragm 35 that changes color when bent, flexed, or otherwise deformed due to upstream fluid pressure oriented substantially perpendicular or normal to the flexible diaphragm 35. The upstream pressure causes the flexible diaphragm 35 to bend or flex outwardly toward the outlet 25. As shown, the flexible diaphragm 35 can flex outwardly the greatest at its central portion where fluid pressure is most concentrated or strong. When seated on the support portion 28, once the flexible diaphragm 35 is bent or flexed, light is reflected from each interface between adjacent layers of the flexible diaphragm 35. The reflected light produces a color in the visible spectrum on the flexible diaphragm 35.

[0036] In some embodiments, as shown, the color change can be strongest at the center portion of the flexible diaphragm, where fluid pressure is most concentrated, and becomes less strong towards the outer periphery of the flexible diaphragm 35. For example, depending on the magnitude of the upstream fluid pressure, the caregiver can see different colors of different intensities.

[0037] Advantageously, due to the structure of the convex shape of the inner wall 42 of the upper housing 10 forming a magnifying lens, the color change of the flexible diaphragm 35 can be easily observed from the outside without having to open the fluid line. The color change indicates the patency of the check valve 100 and can confirm to the user or caregiver that fluid is actually flowing through the check valve 100 as intended. More advantageously, the user or caregiver can confirm that there is a net upstream pressure (and thus an indication of flow through the check valve 100) by simply observing the visual color change of the flexible diaphragm 35. Thus, a separate pressure sensor is not needed to confirm fluid flow.

[0038] Figure 5 A cross-sectional view of the check valve 100 in a closed state is shown in accordance with some embodiments of the present disclosure. As shown, and as described above, the upper housing 10 can include an interior surface having a first portion defining a ceiling 40 of the chamber 30 and a second portion defining a sidewall 42 of the chamber. In some embodiments, the ceiling 40 defines a sealing surface of the check valve 100. As Figure 5 As shown, in the closed state of the check valve 100, the flexible diaphragm 35 contacts the ceiling 40. Because the flexible diaphragm 35 contacts the interior surface defining the ceiling 40, reverse flow (backflow) of fluid from the outlet 25 to the inlet 20 is restricted or prevented.

[0039] During operation, when the downstream pressure (i.e., the pressure exerted by fluid flowing from the outlet 25 to the inlet 20) is applied to the flexible diaphragm 35, the flexible diaphragm 35 can move towards and contact the ceiling 40 to block fluid communication between the inlet 20 and the chamber 30, thereby restricting backflow of fluid from the outlet 25 into the inlet 20. Preventing or restricting backflow of fluid is advantageous because it restricts the backflow of undesirable particulate matter (e.g., contained in a medication being dispensed from the auxiliary path) through the flexible diaphragm 35, thereby hindering the patient from receiving the proper medication dosage concentration or hindering the timely delivery of the medication.

[0040] In one or more embodiments of the present disclosure, the check valve includes an upper housing defining an inlet of the check valve; a lower housing including a support portion and defining an outlet of the check valve; a chamber interposed between and defined by the upper housing and the lower housing for fluidly connecting the inlet and the outlet; and a flexible diaphragm mounted in the chamber to selectively allow fluid flow in a first direction and prevent fluid backflow in a second direction opposite the first direction, the flexible diaphragm including a color changing material, wherein the flexible diaphragm exhibits a color change when the flexible diaphragm is seated on the support portion and is flexed due to a force of fluid flowing in the first direction.

[0041] In aspects of the present disclosure, the flexible diaphragm includes a plurality of periodically stacked layers of transparent material. In aspects of the present disclosure, the upper housing includes an interior surface having a first portion defining a ceiling of the chamber and a second portion defining a sidewall of the chamber; and the portion of the interior surface defining the sidewall of the chamber includes a convex shape. In aspects of the present disclosure, the sidewall having the convex shape includes a transparent material to allow visual observation of the color change. In aspects of the present disclosure, the convex shape of the sidewall forms a magnifying material to enhance visual observation of the color change.

[0042] In aspects of the present disclosure, the flexible diaphragm includes a disc shape. In aspects of the present disclosure, the flexible diaphragm includes a pressure sensor. In aspects of the present disclosure, the flexible diaphragm includes a pressure sensing photonic fiber. In aspects of the present disclosure, the flexible diaphragm changes color when fluid flow in the first direction has a pressure greater than or equal to a predetermined pressure. In aspects of the present disclosure, the flexible diaphragm changes color when subjected to a pressure oriented substantially normal to the flexible diaphragm. In aspects of the present disclosure, the flexible diaphragm includes a transparent rubber material.

[0043] In one or more embodiments of the present disclosure, the check valve includes a valve chamber including an inlet port at an inlet end, an outlet port at an outlet end, and an interior surface defining a ceiling of the chamber and a convexly shaped sidewall; and a flexible diaphragm supported within the valve chamber, wherein the flexible diaphragm includes a plurality of layers of transparent material that exhibit a color change when the flexible diaphragm is seated in the valve chamber and is flexed due to a force of fluid flowing from the inlet port to the outlet port.

[0044] In aspects of the present disclosure, the convexly shaped sidewall comprises a transparent material to allow visual observation of the color change. In aspects of the present disclosure, the convexly shaped sidewall of the flexible septum forms a magnifying material to enhance visual observation of the color change. In aspects of the present disclosure, the flexible septum comprises a disc shape. In aspects of the present disclosure, the flexible septum comprises a pressure sensor. In aspects of the present disclosure, the flexible septum comprises a pressure-sensing photonic fiber. In aspects of the present disclosure, the flexible septum changes color when fluid flow from the inlet port to the outlet port is greater than or equal to a predetermined pressure. In aspects of the present disclosure, the flexible septum changes color when subjected to a fluid force oriented normal to the flexible septum. In aspects of the present disclosure, the transparent material comprises a transparent rubber material.

[0045] The present disclosure is provided to enable any person skilled in the art to practice the various aspects described herein. The disclosure provides various examples of the subject technology, and the subject technology is not limited to these examples. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other aspects.

[0046] Unless specifically stated otherwise, references to a singular term does not exclude the plural or vice versa. Unless specifically stated otherwise, the term "some" refers to one or more. The positiveia singular pronouns (e.g., "his") include the neuter and generic singular pronouns (e.g., "its" and "them"). Headings and subheadings, if any, are used for convenience only and do not limit the application.

[0047] The word "exemplary" is used herein to mean "serving as an example or illustration." Any aspect or design described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other aspects or designs. In one aspect, various alternative configurations and operations can be considered at least equivalent.

[0048] As used herein, the phrase "at least one of," followed by a listing of two or more items, and disjunctive language such as "or", refers to any of the items in the list, or any combination of items in the list. For example, the phrase "at least one of A, B, or C" can refer to only A, only B, or only C; or any combination of A, B, or C. The phrase "at least one of" can refer to at least one, and / or at least one of each item in the list.

[0049] For example, a phrase such as “aspect” does not mean that such aspect is essential to the subject technology, or that such aspect applies to all configurations of the subject technology. A disclosure relating to an aspect can apply to all aspects, or one or more aspects. An aspect can provide one or more examples. A phrase such as “one aspect” does not mean that such aspect is essential to the subject technology, or that such aspect applies to all configurations of the subject technology. A disclosure relating to an aspect can apply to all aspects, or one or more aspects. An aspect can provide one or more examples. A phrase such as “one embodiment” does not mean that such embodiment is essential to the subject technology, or that such embodiment applies to all configurations of the subject technology. A disclosure relating to an embodiment can apply to all embodiments, or one or more embodiments. An embodiment can provide one or more examples. A phrase such as “one embodiment” does not mean that such embodiment is essential to the subject technology, or that such embodiment applies to all configurations of the subject technology. A disclosure relating to an embodiment can apply to all embodiments, or one or more embodiments. An embodiment can provide one or more examples. A phrase such as “configuration” does not mean that such configuration is essential to the subject technology, or that such configuration applies to all configurations of the subject technology. A disclosure relating to a configuration can apply to all configurations, or one or more configurations. A configuration can provide one or more examples. A phrase such as “such configuration” can refer to one or more configurations, or vice versa.

[0050] In one aspect, unless otherwise indicated, all measurements, values, ratings, positions, magnitudes, sizes, and other specifications that are set forth in this specification, including in the claims that follow, are approximate, not exact. In one aspect, they are intended to have a reasonable range that is consistent with the functions to which they relate and with what is customary in the art to which they pertain.

[0051] It should be understood that a specific order or hierarchy of steps or actions within the processes or methods disclosed are an example approach. Based upon implementation preferences, it should be understood that different steps, orders or hierarchies of steps, or actions can be performed based on the example approach. Some steps, actions or processes can be performed simultaneously or in different order. In some implementation preferences or scenarios, certain actions can be omitted. Some or all of the steps, actions or processes can be performed automatically, without user intervention. The following method claims are presented in dependent form to present the elements of the various steps, actions or processes in an example order, and are not meant to be limited to the specific order or hierarchy presented.

[0052] All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether these disclosure is explicitly recited in the claims. The claims of this disclosure are hereby expressly incorporated by reference to the complete disclosure of the taking priority hereto. The applicant reserves the right to amend the claims to expressly recite this disclosure. Under no circumstances can it be used against the applicant in the future, as applicable laws are now or may change over time. The section headings used herein are for organizational purposes only and are not meant to be used as interpretation tools limiting the scope of the claims or the meaning of any terminology within. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the disclosure, and will not be interpreted in an overly literal or restricted way unless expressly so defined herein.

[0053] The titles, summaries, backgrounds, brief summaries, and abstracts of the present disclosure are incorporated herein and are provided as illustrative examples of the present disclosure, and not as limiting descriptions. The submissions are based on the understanding that they will not be used to limit the scope or meaning of the claims. Moreover, in the detailed description, it can be seen that the description provides illustrative examples, and to simplify the present disclosure, various features are combined together in various embodiments. The methods of the present disclosure should not be interpreted as reflecting an intent that the claimed subject matter require more features than are expressly recited in each claim. Rather, as reflected in the claims below, inventive subject matter resides in less than all features of a single disclosed construction or operation. The claims below are hereby incorporated into the detailed description, each claim standing on its own as a separately claimed subject matter.

[0054] The claims are not intended to be limited to the aspects described herein, but are to be accorded the full scope consistent with the language of the claims, and to cover all legal equivalents thereof. Regardless of the language employed, however, none of the claims are intended to encompass subject matter that fails to satisfy the requirements of 35 U.S.C. § 101, 102, or 103, as they are interpreted when read in the context of the specification as a whole.

Claims

1. A check valve characterized by, comprises: an upper housing defining an inlet of the check valve; a lower housing comprising a support portion and defining an outlet of the check valve; a chamber interposed between and defined by the upper housing and the lower housing for fluidly connecting the inlet and the outlet; and a flexible diaphragm mounted in the chamber to selectively allow fluid flow in a first direction and prevent fluid backflow in a second direction opposite the first direction, the flexible diaphragm comprising a color-changing material, wherein the flexible diaphragm exhibits a color change when the flexible diaphragm is seated on the support portion and is flexed due to a force of fluid flowing in the first direction. The flexible diaphragm comprises a plurality of periodically stacked layers of transparent material.

2. The check valve of claim 1, wherein 3. The check valve of claim 1, wherein: the upper housing comprises an interior surface having a first portion defining a ceiling of the chamber and a second portion defining a sidewall of the chamber; and the portion of the interior surface defining the sidewall of the chamber comprises a convex shape. The sidewall having the convex shape comprises a transparent material to allow visual observation of the color change.

4. The check valve of claim 3, wherein The convex shape of the sidewall forms a magnifying material to enhance visual observation of the color change.

5. The check valve of claim 4, wherein The flexible diaphragm comprises a disc shape.

6. The check valve of claim 1, wherein The flexible diaphragm comprises a pressure sensor.

7. The check valve of claim 1, wherein The flexible diaphragm comprises a pressure-sensing photonic fiber.

8. The check valve of claim 1, wherein The flexible diaphragm changes color when fluid flow in the first direction has a pressure greater than or equal to a predetermined pressure.

9. The check valve of claim 1, wherein The flexible diaphragm changes color when subjected to a pressure oriented substantially normal to the flexible diaphragm.

10. The check valve of claim 1, wherein The flexible diaphragm comprises a transparent rubber material.

11. The check valve of claim 1, wherein comprises:

12. A check valve characterized by, a valve chamber comprising an inlet port at an inlet end, an outlet port at an outlet end, and an interior surface defining a ceiling and a convexly shaped sidewall of the chamber; and a flexible diaphragm supported within the valve chamber, wherein the flexible diaphragm comprises a plurality of layers of transparent material that exhibit a color change when the flexible diaphragm is seated in the valve chamber and is flexed due to a force of fluid flowing from the inlet port to the outlet port. The convexly shaped sidewall comprises a transparent material to allow visual observation of the color change.

13. The check valve of claim 12, wherein, The convex shape of the sidewall forms a magnifying material to enhance visual observation of the color change.

14. The check valve of claim 12, wherein, The flexible diaphragm comprises a disc shape.

15. The check valve of claim 12, wherein, The flexible diaphragm comprises a pressure sensor.

16. The check valve of claim 15, wherein, The flexible diaphragm comprises a pressure-sensing photonic fiber.

17. The check valve of claim 16, wherein The flexible diaphragm changes color when fluid flow from the inlet port to the outlet port is greater than or equal to a predetermined pressure.

18. The check valve of claim 12, wherein, The flexible diaphragm changes color when subjected to a fluid force oriented normal to the flexible diaphragm.

19. The check valve of claim 12, wherein, The transparent material comprises a transparent rubber material.

20. The check valve of claim 12, wherein ​

Images