Backflow prevention device and dialysis apparatus having the same

Abstract

A backflow prevention device (1) comprises: an inlet chamber (2) comprising at least two ports (21, 22), wherein the first port (21) is for receiving fluid; a chamber separation member (6) comprising a partition (61) and a bleed valve (62); an outlet chamber (4) separated from the inlet chamber (2) by the partition (61); the bleed valve (62) is operatively connected with the partition (61) for opening or closing a discharge port (43) of the outlet chamber (4); wherein fluid is allowed to be delivered from the outlet chamber (4) only when the bleed valve (62) is closed by means of a pressure difference applied on the partition (61). Also related to a dialysis apparatus comprising the backflow prevention device (1). The backflow prevention device (1) has a simple structure, a reduced dead zone and a small size, and can work reliably.

Description

Technical Field

[0001] The present invention relates to a backflow prevention device for medical and health purposes and a dialysis apparatus including the backflow prevention device. Background Technology

[0002] Backflow prevention devices are typically installed between the fluid supply source and the connected equipment used to receive fluid from the fluid supply source, in order to protect the fluid supply source from contamination or pollution by the connected equipment.

[0003] Air gap separation is a common method to prevent the risk of backflow contamination. However, air gap separation cannot be used in certain applications, such as pressurized operation.

[0004] In this situation, a check valve or double check valve backflow preventer is the basic form of backflow prevention device. However, such backflow preventers are unreliable because the valve may not close completely due to particles or debris in the fluid pipeline; sometimes, valve failure cannot be completely avoided either.

[0005] In certain critical applications, more complex devices with redundancy features, such as reduced-pressure zone (RTZ) units, are used. However, most RTZ units on the market are primarily designed for portable water supply systems and are unsuitable for medical applications for the following reasons:

[0006] 1) The internal flow paths of most RTZ devices are difficult to sterilize. These devices have atmospheric vents and test valves, which can introduce bacteria into the distribution lines. If the device is used in a medical device, bacteria can multiply on the device and recontaminate the treated fluid, potentially harming the patient.

[0007] 2) During routine disinfection, chemical disinfectants may remain in the internal flow path of a conventional RTZ device. The captured disinfectant can then be released into the treated fluid, such as reverse osmosis water, during dialysis treatment, thus exposing the patient to disinfectant toxicity.

[0008] 3) Most RTZ devices are made of materials unsuitable for use with medical devices. Certain metals can contaminate the fluid and harm the patient. Summary of the Invention

[0009] In view of the problems existing in the prior art, the object of the present invention is to provide an improved backflow prevention device and a dialysis device including the backflow prevention device.

[0010] To achieve this objective, according to a first aspect, a backflow prevention device is provided, comprising: an inlet chamber including at least two ports, wherein a first port is for receiving fluid; a chamber partition member including a partition and a relief valve; an outlet chamber separated from the inlet chamber by the partition; the relief valve being operatively connected to the partition for opening or closing the outlet port of the outlet chamber; wherein fluid is permitted to be delivered from the outlet chamber only when the relief valve is closed by means of a pressure differential applied to the partition.

[0011] According to an alternative embodiment, the second port of the inlet oral cavity is fluidly connected to a spring-loaded inlet check valve for conveying fluid flowing from the first port through the inlet oral cavity.

[0012] According to an alternative embodiment, the pressure differential is established by the spring-loaded inlet check valve, which establishes a pressure differential across the separator when fluid enters the inlet chamber.

[0013] According to an alternative embodiment, the second port of the inlet chamber is fluidly connected to a differential pressure generator and an inlet check valve for conveying fluid flowing from the first port through the inlet chamber.

[0014] According to an alternative embodiment, the pressure difference is established by the pressure difference generator, which establishes a pressure difference across the separator when fluid enters the inlet chamber.

[0015] According to an alternative embodiment, the inlet check valve is fluidly connected between the inlet chamber and the outlet chamber to allow fluid to flow only from the inlet chamber to the outlet chamber along the forward flow path of the fluid.

[0016] According to an alternative embodiment, the backflow prevention device further includes an outlet check valve fluidly connected to the outlet chamber to allow fluid to flow only through the outlet check valve to deliver fluid from the outlet chamber; optionally, the outlet check valve is a spring-loaded check valve.

[0017] According to an optional embodiment, the backflow prevention device further includes: a discharge port cleaning valve for flushing and / or disinfecting the discharge port, the discharge port cleaning valve being fluidly connected in parallel with a spring-loaded inlet check valve between the inlet chamber (2) and the outlet chamber (4); or a combination of the inlet check valve and a differential pressure generator connected in series with the inlet check valve being fluidly connected in parallel between the inlet chamber and the outlet chamber.

[0018] According to an alternative embodiment, when there is a leak in the inflow path to the outlet chamber and / or a leak in the transport flow path from the outlet chamber, the discharge port is used to discharge fluid from the outlet chamber as a backflow prevention measure.

[0019] According to an alternative embodiment, the separator is configured as a flexible membrane, and optionally, is configured to have a circular shape.

[0020] According to an alternative embodiment, the chamber partition is supported by a support portion extending radially inward from the corresponding inner wall of the backflow prevention device.

[0021] According to an alternative embodiment, the relief valve is configured to connect with a separator to form a relief valve plunger of an integral assembly.

[0022] According to an alternative embodiment, the component is supported by a spring on the bottom wall of the outlet chamber, optionally a helical spring surrounding the vent valve plunger.

[0023] According to an optional embodiment, the backflow prevention device further includes an inflow detection device for detecting leakage in the discharge port when there is no fluid consumption from the outlet chamber in the fourth port but fluid flows into the outlet chamber through the inflow path. Optionally, the inflow detection device includes a pair of electrodes disposed on both sides of an electrically insulated inlet check valve disposed in the inflow path.

[0024] According to an alternative embodiment, the inlet chamber is positioned above the outlet chamber, and optionally, each chamber is formed in a cylindrical shape.

[0025] According to an alternative embodiment, the outlet chamber has at least two ports, wherein a third port is fluidly connected to the outlet of an inlet check valve that is fluidly disposed between the inlet and outlet chambers, and a fourth port is fluidly connected to the inlet of an outlet check valve for conveying fluid from the outlet chamber.

[0026] According to an alternative embodiment, the relief valve plunger has a stem and a sealing head with a diameter larger than the stem. Optionally, the stem and sealing head are integrally formed with the separator and / or molded in one piece.

[0027] According to an alternative embodiment, the discharge port is centrally formed in the bottom wall of the outlet chamber; and / or the discharge port is fluidly connected to a funnel-shaped discharge pipe for air gap separation.

[0028] According to one alternative embodiment, at least the portion of the backflow prevention device in contact with the fluid is formed of a biocompatible material.

[0029] According to an alternative embodiment, the inlet and / or outlet chambers have cylindrical cavities with a height correspondingly smaller than their radius.

[0030] According to the second aspect, a dialysis apparatus including the aforementioned backflow prevention device is provided.

[0031] According to the present invention, the backflow prevention device has a simple structure, reduced dead zone and small size, and can operate reliably. Attached Figure Description

[0032] The invention and its advantages will be further understood by reading the following detailed description of some preferred exemplary embodiments with reference to the accompanying drawings, wherein...

[0033] Figure 1 A schematic cross-sectional view of a backflow prevention device according to an exemplary embodiment of the present invention is shown.

[0034] Figure 2 As shown Figure 1 A top view of a portion of the backflow prevention device shown.

[0035] Figure 3 A schematic cross-sectional view of a portion of a backflow prevention device, particularly suitable for high-flow-rate applications, is shown according to another exemplary embodiment of the invention.

[0036] Figure 4 A schematic cross-sectional view of a backflow prevention device according to another exemplary embodiment of the present invention is shown. Detailed Implementation

[0037] Some exemplary embodiments of the invention will be described in more detail below with reference to the accompanying drawings to better understand the basic ideas of the invention.

[0038] Figure 1 A schematic cross-sectional view of a backflow prevention device 1 according to an exemplary embodiment of the present invention is shown.

[0039] like Figure 1As shown, the backflow prevention device 1 mainly includes: an inlet chamber 2 having a first port 21 and a second port 22, a spring-loaded inlet check valve 3, an outlet chamber 4 having a third port 41, a fourth port 42 and a discharge port 43, preferably a spring-loaded outlet check valve 5, and a chamber partition member 6. The inlet chamber 2 is used to receive fluid from the fluid supply source 7 via the first port 21. The inlet check valve 3 is fluidly connected between the second port 22 and the third port 41 to allow fluid to flow only from the inlet chamber 2 to the outlet chamber 4. The fourth port 42 of the outlet chamber 4 is fluidly connected to the outlet check valve 5. The outlet check valve 5 is fluidly connected to the device 8 that requires fluid and allows fluid to flow only from the fourth port 42 to the device 8. The chamber partition member 6 includes a partition 61 that separates the inlet chamber 2 and the outlet chamber 4 and a relief valve 62 connected to the partition 61 and located within the outlet chamber 4. During operation, when a sufficient pressure differential is established through the spring-loaded inlet check valve 3, the relief valve 62 can move toward the discharge port 43 by means of the movement or elastic deformation of the separator 61 to seal the discharge port 43. Although the discharge port 43 may act as a valve seat during operation, the term "relief valve" does not include the discharge port 43 in the context of this application. In the initial state, the relief valve 62 is spaced apart from the discharge port 43 to keep the discharge port 43 open.

[0040] like Figure 1 As further shown, the relief valve 62 is preferably configured as a relief valve plunger connected to the separator 61 to form an integral assembly.

[0041] According to an exemplary embodiment of the present invention, the fluid may be dialysate or reverse osmosis water. In this case, the device may be a dialysis device for dialysis treatment.

[0042] According to an exemplary embodiment of the present invention, the separator 61 can be configured as a flexible membrane preferably integrally formed with the vent valve plunger, thereby enabling a simple structural design.

[0043] According to an exemplary embodiment of the present invention, such as Figure 1 As shown, the relief valve plunger has a stem 63 and a sealing head 64, the diameter of which is larger than that of the stem 63. For low-flow applications, the stem 63 and the sealing head 64 are integrally formed and / or molded in one piece from the same material as the separator 61. In operation, the sealing head 64 is used to seal the discharge port 43.

[0044] According to an exemplary embodiment of the present invention, such as Figure 1 As shown, the inlet chamber 2 and the outlet chamber 4 can be stacked one on top of the other.

[0045] Figure 2 As shown Figure 1A top view of a portion of the backflow prevention device 1 shown.

[0046] Preferably, such as Figure 1 and Figure 2 As shown, the inlet chamber 2 and the outlet chamber 4 each have a cylindrical body with the same diameter.

[0047] According to another exemplary embodiment of the present invention, such as Figure 1 As shown, the first port 21 and the second port 22 can extend outward from the cylindrical body of the inlet chamber 2 along the diameter direction, and / or the third port 41 and the fourth port 42 can extend outward from the cylindrical body of the outlet chamber 4 along the diameter direction, and / or the discharge port 43 can extend downward from the center of the bottom wall of the outlet chamber 4. This arrangement reduces the flow resistance of the backflow prevention device, allows for a compact design, and facilitates easy cleaning and / or disinfection of the internal spaces of the inlet chamber 2 and / or the outlet chamber 4.

[0048] Preferably, in the assembled state, the first port 21 and the fourth port 42 are oriented in a first common direction such that they overlap when viewed from a top view of the backflow prevention device 1. Similarly, in the assembled state, the second port 22 and the third port 41 are oriented in a second common direction opposite to the first common direction. With this arrangement, the backflow prevention device 1 can have a neat appearance.

[0049] like Figure 1 As further shown, the discharge port 43, when open, can be used to discharge fluid from the outlet chamber 4 to any suitable device, such as a receiver (not shown). To further prevent contamination from the discharge port 43, the discharge port 43 is connected to the funnel-shaped discharge pipe 17 to achieve air gap separation.

[0050] According to an exemplary embodiment of the invention, the discharge port cleaning valve 9 is fluidly connected in parallel between the inlet chamber 2 and the outlet chamber 4, along with a spring-loaded inlet check valve 3 or optionally an inlet check valve having a differential pressure generator connected in series. This allows fluid to be directed from the fluid supply source 7 to the discharge port 43 via the inlet chamber 2, the open discharge port cleaning valve 9, and the outlet chamber 4 if the discharge port cleaning valve 9 is opened to equalize the pressure on both sides of the separator 61. Therefore, the discharge port 43 can be flushed with fluid from the fluid supply source 7. The discharge port 43 can also be disinfected using any suitable fluid, thanks to the discharge port cleaning valve 9.

[0051] According to an exemplary embodiment of the present invention, the separator 61 has a circular shape and is configured to align with the discharge port 43. Figure 2 In the middle, the separator 61 is shown by the dashed line 10.

[0052] like Figure 1As shown, the separator 61 can be supported in the circumferential direction at the support portion 11, which extends radially inward from the corresponding inner wall of the backflow prevention device 1.

[0053] According to an exemplary embodiment of the present invention, an inflow detection device is provided to detect whether fluid flows through an inlet check valve 3. Preferably, the inflow detection device includes a pair of inflow detection electrodes 12 on both sides of the electrically insulated inlet check valve 3. When fluid flows through the inlet check valve 3, the conductivity between the pair of electrodes 12 increases. Additionally, the inflow detection device can be used to detect whether there is a leak in a relief valve, which will be further described below.

[0054] Figure 3 A schematic cross-sectional view of a portion of a backflow prevention device, particularly suitable for high-flow-rate applications, is shown according to another exemplary embodiment of the invention.

[0055] like Figure 3 As shown, the chamber partition 6 can be supported by a spring 13, preferably a helical spring. The spring 13 can be arranged around the relief valve plunger and can be supported by the portion of the bottom wall of the outlet chamber 4 surrounding the discharge port 43. In this way, the spring 13 ensures that the relief valve plunger is always stable and positioned correctly to completely close the discharge port 43.

[0056] To facilitate the assembly of the backflow prevention device 1 and simplify its structure, the backflow prevention device 1 may include a first component 14 and a second component 15, which can be arranged along the... Figure 3 The assembly planes 16 are only schematically shown together. Preferably, a sealing device such as an O-ring or a resilient separator itself is provided between the first component 14 and the second component 15. According to an exemplary embodiment of the invention, the first component 14 and the second component 15 are assembled together by means of screws or other fastening devices (not shown).

[0057] According to an exemplary embodiment of the present invention, the first component 14 includes at least an inlet chamber 2 and a chamber partition member 6, and the second component 15 includes at least an outlet chamber 4 and an outlet port 43.

[0058] For dialysis applications, at least the portion of the backflow prevention device 1 that comes into contact with the fluid is made of a biocompatible material that can withstand both heat and chemical sterilization. Biocompatible materials may include, for example, parylene, gluten, nitrocellulose, etc.

[0059] The backflow prevention device 1 of the present invention can be configured such that the inlet chamber 2 and / or the outlet chamber 4 have a smooth-profile internal shape and a reduced dead zone, especially when the inlet chamber 2 and / or the outlet chamber 4 have the above-mentioned cylindrical body.

[0060] According to an exemplary embodiment of the invention, the inlet oral cavity 2 and / or the outlet oral cavity 4 can be configured with a compact design and minimal cavity volume to ensure adequate fluid flow along the inner surface of the cavity, thereby avoiding biological problems. For example, the inlet oral cavity 2 and / or the outlet oral cavity 4 can be configured with a cylindrical cavity whose height is correspondingly smaller than its radius.

[0061] The operation of the backflow prevention device 1 will be described in detail below.

[0062] The backflow prevention device 1 of the present invention operates based on the hydraulic principle that fluid will not flow from a low-pressure area to a high-pressure area. Since a pressure differential can be established via a spring-loaded inlet check valve 3, when the pressure of the fluid supplied to the inlet chamber 2 is higher than the pressure in the outlet chamber 4 by a predetermined amount, the relief valve 62 will remain closed. Then, if the pressure in the inlet chamber 2 increases to a level sufficient to open the inlet check valve 3, fluid will flow into the outlet chamber 4, further opening the outlet check valve 5. When the pressure in the inlet chamber 2 drops below a set value, the relief valve 62 will open, and the fluid in the outlet chamber 4 will be discharged through the discharge port 43. If the pressure in the outlet chamber 4 is sufficient to open the relief valve 62 and / or there is a malfunction in the outlet check valve 5, the fluid in the outlet chamber 4 will also be discharged through the discharge port 43.

[0063] If there is a leak in the inlet check valve 3, the pressure in the inlet chamber 2 and the outlet chamber 4 will become equalized, and the relief valve 62 will be opened to transfer the backflow fluid to the outlet port 43.

[0064] If there is a leak in the outlet check valve 5, the backflow fluid will first be blocked by the inlet check valve 3. When the backflow fluid pressure reaches a certain value, the relief valve 62 will be opened to transfer the backflow fluid to the discharge port 43.

[0065] If both the inlet check valve 3 and the outlet check valve 5 are leaking, the vent valve 62 will also be opened to transfer the backflow fluid to the discharge port 43.

[0066] If a leak exists in the relief valve 62, it can be detected by checking whether fluid flows through the inlet check valve 3, for example, by measuring the conductivity between a pair of electrodes 12, with the downstream flow path (not shown) of the backflow prevention device 1 cut off. If fluid still flows through the inlet check valve 3 in this state, a leak may exist in the relief valve 62.

[0067] Those skilled in the art will understand that differential pressure can also be generated in other ways, such as by using a separate differential pressure generator. Figure 4 A schematic cross-sectional view of a backflow prevention device 1' according to another exemplary embodiment of the present invention is shown.

[0068] like Figure 4 As shown, the backflow prevention device 1′ differs from the backflow prevention device 1 only in that it uses a combination of an inlet check valve 3′ and a differential pressure generator 18 connected in series with the inlet check valve 3′ instead of a spring-loaded inlet check valve 3. In another embodiment, the differential pressure generator 18 is disposed between the fluid supply source 7 and the inlet chamber 2, preferably before the first port 21, so as to generate a differential pressure on the separator 61 when fluid enters the inlet chamber 2.

[0069] According to the present invention, the backflow prevention device has a simple structure, reduced dead zone and small size, and can operate reliably.

[0070] Although certain embodiments have been described, these embodiments are given by way of example only and are not intended to limit the scope of the invention. The appended claims and their equivalents are intended to cover all modifications, substitutions, and alterations that fall within the scope and spirit of the invention.

Claims

1. A backflow prevention device (1), comprising: An inlet chamber (2) includes at least two ports, wherein a first port (21) is used to receive fluid; The chamber partition (6) includes a partition (61) and a relief valve (62); The out-of-oral chamber (4) is separated from the in-oral chamber (2) by a partition (61) and includes an exhaust port and a fourth port; The vent valve (62) is operatively connected to the separator (61) for opening or closing the discharge port (43) of the oral cavity (4); Fluid is allowed to be delivered from the fourth port of the outlet chamber (4) only when the relief valve (62) is closed by means of the pressure difference applied to the separator (61); The second port (22) of the inlet oral cavity (2) is fluidly connected to the outlet oral cavity (4) for conveying fluid flowing from the first port (21) through the inlet oral cavity (2); and The inlet check valve is fluidly connected between the second port (22) and the outlet chamber (4) to allow fluid to flow from the inlet chamber (2) to the outlet chamber (4) only along the forward flow path of the fluid.

2. The backflow prevention device (1) according to claim 1, wherein... The inlet check valve is a spring-loaded inlet check valve, and the second port (22) of the inlet chamber (2) is fluidly connected to the spring-loaded inlet check valve.

3. The backflow prevention device (1) according to claim 2, wherein... The pressure difference is established by the spring-loaded inlet check valve, which establishes a pressure difference on both sides of the separator (61) when fluid enters the inlet chamber (2).

4. The backflow prevention device (1) according to claim 1, wherein The second port (22) of the inlet chamber (2) is fluidly connected to the differential pressure generator (18) and the inlet check valve.

5. The backflow prevention device (1) according to claim 4, wherein... The pressure difference is established by the pressure difference generator (18), which establishes a pressure difference on both sides of the separator (61) when the fluid enters the inlet chamber (2).

6. The backflow prevention device (1) according to claim 1, wherein, The backflow prevention device (1) further includes: An outlet check valve (5) is fluidly connected to an outlet chamber (4) to allow fluid to flow only through the outlet check valve (5) and deliver fluid from the outlet chamber (4).

7. The backflow prevention device (1) according to claim 6, wherein, The outlet check valve (5) is a spring-loaded check valve.

8. The backflow prevention device (1) according to claim 1, wherein, The backflow prevention device (1) further includes: A discharge port cleaning valve (9) for flushing and / or disinfecting the discharge port (43) is fluidly connected in parallel with a spring-loaded inlet check valve between the inlet chamber (2) and the outlet chamber (4); or fluidly connected in parallel with a combination of an inlet check valve and a differential pressure generator (18) connected in series with the inlet check valve between the inlet chamber (2) and the outlet chamber (4).

9. The backflow prevention device (1) according to claim 8, wherein... When there is a leak in the inflow path to the outlet chamber (4) and / or a leak in the transport flow path from the outlet chamber (4), the discharge port is used to discharge the fluid in the outlet chamber (4) as a backflow prevention measure.

10. The backflow prevention device (1) according to claim 1, wherein The separator (61) is configured as a flexible membrane.

11. The backflow prevention device (1) according to claim 10, wherein The separator (61) is configured to have a circular shape.

12. The backflow prevention device (1) according to claim 1, wherein The chamber partition (6) is supported by a support portion (11) extending radially inward from the corresponding inner wall of the backflow prevention device (1).

13. The backflow prevention device (1) according to claim 1, wherein The relief valve (62) is configured to connect with the separator (61) to form a relief valve plunger of an integral assembly.

14. The backflow prevention device (1) according to claim 13, wherein The component is supported by a spring (13) on the bottom wall of the outlet chamber (4).

15. The backflow prevention device (1) according to claim 14, wherein The spring (13) is a helical spring and surrounds the vent valve plunger.

16. The backflow prevention device (1) according to claim 1, wherein, The backflow prevention device (1) further includes: An inflow detection device is used to detect a leak in the discharge port (43) when there is no fluid consumption from the discharge chamber (4) in the fourth port (42) but fluid flows through the inflow path to the discharge chamber (4).

17. The backflow prevention device (1) according to claim 16, wherein The inflow detection device includes a pair of electrodes (12) disposed on both sides of an electrically insulated inlet check valve located in the inflow path.

18. The backflow prevention device (1) according to any one of claims 1 to 17, wherein The inlet chamber (2) is positioned above the outlet chamber (4).

19. The backflow prevention device (1) according to claim 18, wherein Each of the inlet chamber (2) and the outlet chamber (4) is formed in a cylindrical shape.

20. The backflow prevention device (1) according to claim 1, wherein The inlet chamber (2) is positioned above the outlet chamber (4).

21. The backflow prevention device (1) according to claim 1, wherein The oral cavity (4) has at least two ports, wherein, The third port (41) is fluidly connected to the outlet of the inlet check valve between the inlet chamber (2) and the outlet chamber (4), and the fourth port (42) is fluidly connected to the inlet of the outlet check valve (5) for conveying fluid from the outlet chamber (4).

22. The backflow prevention device (1) according to claim 13, wherein The vent valve plunger has a rod (63) and a sealing head (64) with a diameter larger than that of the rod (63).

23. The backflow prevention device (1) according to claim 22, wherein... The rod (63) and sealing head (64) are integrally formed with the separator (61) and / or molded in one piece.

24. The backflow prevention device (1) according to any one of claims 1 to 18, 19 to 23, wherein The discharge port (43) is centrally formed in the bottom wall of the discharge chamber (4); and / or The discharge port (43) is fluidly connected to the funnel-shaped discharge pipe (17) for air gap separation.

25. The backflow prevention device (1) according to claim 1, wherein The discharge port (43) is centrally formed in the bottom wall of the discharge chamber (4); and / or The discharge port (43) is fluidly connected to the funnel-shaped discharge pipe (17) for air gap separation.

26. The backflow prevention device (1) according to claim 18, wherein The discharge port (43) is centrally formed in the bottom wall of the discharge chamber (4); and / or The discharge port (43) is fluidly connected to the funnel-shaped discharge pipe (17) for air gap separation.

27. The backflow prevention device (1) according to claim 1, wherein The portion of the backflow prevention device (1) that is in contact with the fluid is made of a biocompatible material.

28. The backflow prevention device (1) according to claim 18, wherein The inlet chamber (2) and / or outlet chamber (4) have cylindrical cavities with a height correspondingly smaller than their radius.

29. A dialysis device, wherein, The dialysis apparatus includes a backflow prevention device (1) according to any one of claims 1 to 28.

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