Check valve having adjustable opening / closing pressure

Abstract

A check valve having an adjustable opening / closing pressure, comprising a valve body (1). A working cavity (11) is provided in the valve body (1), and a first interface (12) and a second interface (13) communicated with an external pipeline and the working cavity (11) are respectively provided on two sides of the valve body (1); a mounting hole is communicated with the top of the working cavity (11) in a first direction, and an inner threaded portion is provided on the inner wall of the mounting hole; a valve rod (2) movably passes through the mounting hole in the first direction, an outer threaded portion (21) is provided on the outer wall of the valve rod (2), and the outer threaded portion (21) is threadedly connected to the inner threaded portion; a valve core (3) is slidably provided in the working cavity (11) in the first direction, and an elastic member (4) is provided between the top of the valve core (3) and the bottom of the valve rod (2); and when the check valve is in an initial state, the valve core (3) blocks the communication position of the first interface (12) and the second interface (13). The check valve allows flexible adjustment of the opening / closing pressure, can adapt to use environments of different opening / closing pressures, and has high applicability.

Description

A check valve with adjustable opening and closing pressure

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application filed with the Patent Office of China on March 12, 2024, with application number 202410280760.6 and invention name “A check valve with adjustable opening and closing pressure”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present application relates to the field of valve technology, and in particular to a check valve with adjustable opening and closing pressure. Background Art

[0004] A check valve is a valve that automatically opens and closes its disc based on the flow of the medium itself, preventing the backflow of the medium. It is also known as a non-return valve, one-way valve, reverse flow valve, or back-pressure valve. A check valve is an automatic valve whose primary functions are to prevent the backflow of the medium, reverse rotation of the pump and drive motor, and release of the medium from the container.

[0005] Traditional check valves usually determine the medium opening pressure (i.e., opening and closing pressure) by compressing the spring coefficient of the spring. The opening and closing pressure of traditional check valves are usually set before leaving the factory. It is difficult to adjust the opening and closing pressure of the check valve, and it cannot be applied to different use environments with different opening and closing pressures, and its applicability is poor.

[0006] Summary of the Invention

[0007] Therefore, the technical problem to be solved by this application is to overcome the defects of the check valve in the prior art that the opening and closing pressures are difficult to adjust, cannot be adapted to the use environment with different opening and closing pressures, and have poor applicability, thereby providing a check valve with adjustable opening and closing pressures.

[0008] A check valve with adjustable opening and closing pressure is provided in the present application, comprising:

[0009] A valve body having a working chamber therein, wherein a first interface and a second interface connecting an external pipeline and the working chamber are respectively provided on both sides of the valve body; a mounting hole is connected to the top of the working chamber along the first direction, and an inner wall of the mounting hole is provided with an internal threaded portion;

[0010] a valve stem, movably arranged in the mounting hole along a first direction, and having an external threaded portion on an outer wall thereof, wherein the external threaded portion is threadedly connected to the internal threaded portion;

[0011] A valve core is arranged in the working chamber for sliding along a first direction, and an elastic member is arranged between the top of the valve core and the bottom of the valve stem; when the check valve is in an initial state, the valve core blocks the connection between the first interface and the second interface.

[0012] A check valve with adjustable opening and closing pressure according to the present application has at least the following technical effects:

[0013] 1. An internal threaded portion matching the external threaded portion is provided on the inner wall of the mounting hole, and an elastic member is provided between the bottom of the valve stem and the top of the valve core; when the opening and closing pressure of the check valve needs to be adjusted according to the actual use environment, the valve stem is driven to rotate in the mounting hole, so that the valve stem is raised and lowered under the threaded connection of the internal threaded portion and the external threaded portion, and the compression amount of the elastic member is steplessly adjusted, thereby adjusting the pressure of the elastic member pressing down the valve core, and then flexibly adjusting the opening and closing pressure of the check valve, which can adapt to the use environment with different opening and closing pressures and has strong applicability.

[0014] 2. Compared with the original product structure, this check valve only adds an internal thread part and an external thread part, which can be compatible with the parts of the original product. Without basically changing the original product structure, the opening and closing pressure can be flexibly adjusted to adapt to different opening and closing pressure usage environments, and it has strong applicability.

[0015] 3. By rotating the adjustment valve stem in the mounting hole, the compression of the elastic member can be fine-tuned, thereby fine-tuning the opening and closing pressure of the check valve, thereby compensating for the processing errors of the components of the check valve and the effects of the assembly errors on the accuracy of the opening and closing pressures. This is particularly suitable for use in environments with high requirements for the accuracy of the opening and closing pressures, and can reduce the processing and assembly difficulty of the check valve, reduce the manufacturing cost of the check valve, and improve market competitiveness.

[0016] Optionally, when the first interface and the second interface are in a connected state, the valve core is lifted along a first direction and blocks the working cavity to form a closed cavity.

[0017] Optionally, the elastic member is configured as one of a coil spring, a disc spring or a wave spring.

[0018] Optionally, a connecting rod is coaxially protruded from the bottom of the valve stem, the cross-sectional area of ​​the connecting rod perpendicular to the first direction is smaller than the cross-sectional area of ​​the valve stem perpendicular to the first direction, and the connecting rod is arranged in the working chamber; the top end of the elastic member is sleeved outside the connecting rod, and the top end surface of the elastic member abuts against the bottom end surface of the valve stem.

[0019] Optionally, a mounting groove is provided on the top surface of the valve core, the bottom end of the elastic member is embedded in the mounting groove, and the bottom end surface of the elastic member abuts against the inner bottom wall of the mounting groove.

[0020] Optionally, an anti-slip pad is provided between the bottom end surface of the valve stem and the top end surface of the elastic member, and the anti-slip pad is sleeved outside the connecting rod, and the cross-sectional area of ​​the anti-slip pad perpendicular to the first direction is larger than the cross-sectional area of ​​the valve stem perpendicular to the first direction.

[0021] Optionally, a sliding groove is recessed on the top wall of the working cavity, and the sliding groove is concentrically arranged with the mounting hole and communicated with the mounting hole; the anti-slip pad is slidably arranged in the sliding groove along a first direction.

[0022] Optionally, the mounting hole is set as a stepped hole, and the end of the mounting hole away from the working chamber along the first direction is set as a large diameter hole, and a sealing filler is provided between the inner wall of the large diameter hole and the outer wall of the valve stem; the internal threaded portion is provided on the inner wall of the small diameter hole of the mounting hole.

[0023] Optionally, a gasket is provided on the outer sleeve of the valve stem, one end of the gasket abuts against the bottom end surface of the sealing filler, and the other end of the gasket abuts against the inner bottom wall of the large-diameter hole; the top end of the external threaded portion is located in the gasket;

[0024] And / or, an end surface of the small-diameter hole of the sealing packing facing away from the mounting hole abuts against a press sleeve, an end of the press sleeve facing away from the sealing packing abuts against a pressure plate, and the pressure plate is detachably connected to the top end of the valve body; a through hole is formed on the pressure plate along the first direction, and the valve stem slides through the through hole along the first direction;

[0025] And / or, the top end of the working chamber passes through the valve body along the first direction, the top end of the valve body is detachably connected to a valve cover, the valve cover covers the working chamber, and the mounting hole is provided on the valve cover along the first direction.

[0026] Optionally, a spiral wound gasket is provided between the bottom end surface of the valve cover and the top end surface of the valve body;

[0027] And / or, a first internally threaded hole is provided on the top surface of the valve body, a first through-hole is provided on the valve cover at a position corresponding to the first internally threaded hole, and the first through-hole penetrates the valve cover in a first direction; during assembly, a first fastening bolt passes through the first through-hole and is threadedly connected to the first internally threaded hole;

[0028] And / or, a second internal threaded hole is provided on the top surface of the valve cover, and a second through-hole is provided on the pressure plate at a position corresponding to the second internal threaded hole, and the second through-hole passes through the pressure plate along the first direction; during assembly, the second fastening bolt passes through the second through-hole and is threadedly connected to the second internal threaded hole.

[0029] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the specific implementation methods or the description of the prior art. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0031] FIG1 is a schematic structural diagram of a check valve with adjustable opening and closing pressure in an initial state according to the present embodiment;

[0032] FIG2 is a partial enlarged schematic diagram of FIG1 ;

[0033] FIG3 is a schematic structural diagram of a check valve with adjustable opening and closing pressure according to this embodiment, in a state where the first port and the second port are connected.

[0034] Explanation of the accompanying drawings: 1-valve body, 11-working chamber, 12-first interface, 13-second interface; 2-valve stem, 21-external threaded part, 22-connecting rod, 23-anti-slip pad; 3-valve core, 31-installing groove; 4-elastic part; 5-valve cover, 51-sliding groove, 52-wound gasket, 53-first fastening bolt; 61-sealing packing, 62-gasket, 63-pressing sleeve, 64-pressure plate, 65-second fastening bolt. DETAILED DESCRIPTION

[0035] The following is a clear and complete description of the technical solution of this application in conjunction with the accompanying drawings. It should be understood that the embodiments described are only a portion of the embodiments of this application, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of this application without inventive effort are intended to fall within the scope of protection of this application.

[0036] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this application and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0037] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0038] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0039] As shown in Figures 1 to 3, a check valve with adjustable opening and closing pressure provided in this embodiment includes a valve body 1, wherein the valve body 1 is provided with a working chamber 11, and a first interface 12 and a second interface 13 are provided on both sides of the valve body 1, respectively, which are connected to an external pipeline and the working chamber 11; a mounting hole is connected to the top of the working chamber 11 along a first direction, and the inner wall of the mounting hole is provided with an internal thread; a valve stem 2 is movably inserted into the mounting hole along the first direction, and the outer wall of the valve stem 2 is provided with an external thread 21, and the external thread 21 is threadedly connected to the internal thread; a valve core 3 is slidably provided in the working chamber 11 along the first direction, and an elastic member 4 is provided between the top of the valve core 3 and the bottom of the valve stem 2; as shown in Figure 3, when the check valve is in an initial state, the valve core 3 blocks the connection between the first interface 12 and the second interface 13. It can be understood that the first direction in this embodiment refers to the first direction in Figure 1.

[0040] The check valve of this embodiment is provided with an internal threaded portion matching the external threaded portion 21 on the inner wall of the mounting hole, and an elastic member 4 is provided between the bottom of the valve stem 2 and the top of the valve core 3. When the opening and closing pressure of the check valve of this embodiment needs to be adjusted according to the actual use environment, the valve stem 2 is driven to rotate within the mounting hole, causing the valve stem 2 to rise and fall under the threaded connection between the internal threaded portion and the external threaded portion 21, steplessly adjusting the compression of the elastic member 4, thereby adjusting the pressure of the elastic member 4 pressing down on the valve core 3, and thus flexibly adjusting the opening and closing pressure of the check valve of this embodiment. It can adapt to different use environments with different opening and closing pressures and has strong applicability. After the compression of the elastic member 4 is steplessly adjusted to the required amount, the position of the valve stem 2 is locked by the threaded engagement force of the internal threaded portion and the external threaded portion 21, thereby limiting the top position of the elastic member 4. This can effectively prevent the compression of the elastic member 4 in the initial state from changing, and ensure the stability of the opening and closing pressure after adjustment. At the same time, the check valve of this embodiment only adds an internal threaded portion and an external threaded portion 21 compared to the original product structure, and can be compatible with the parts of the original product. Without substantially changing the original product structure, the opening and closing pressure can be flexibly adjusted to adapt to different opening and closing pressure usage environments, thus having strong applicability. The check valve of this embodiment can fine-tune the compression of the elastic member 4 by rotating the adjustment valve stem 2 within the mounting hole, thereby fine-tuning the opening and closing pressure of the check valve of this embodiment. This can compensate for the effects of machining errors and assembly errors of the components of the check valve of this embodiment on the accuracy of the opening and closing pressure. This is particularly suitable for use environments with high requirements for the accuracy of the opening and closing pressure, and can reduce the machining and assembly difficulty of the check valve of this embodiment, reduce the manufacturing cost of the check valve of this embodiment, and improve market competitiveness.

[0041] The check valve of this embodiment hides the elastic member 4 in the working chamber 11 , so that the elastic member 4 is not easily corroded by external moisture during long-term use, thereby ensuring the service life of the elastic member 4 .

[0042] The working principle of the check valve of this embodiment is as follows: as shown in Figure 3, when the medium flows into the first interface 12 and the medium pressure is greater than the pressure of the elastic member 4 pressing down on the valve core 3 (i.e., the opening and closing pressure), the medium pressure will push the valve core 3 to move upward, thereby connecting the first interface 12 and the second interface 13, and then the medium will flow; as shown in Figure 1, when the medium pressure is less than the pressure of the elastic member 4 pressing down on the valve core 3 (i.e., the opening and closing pressure), the valve core 3 moves downward under the action of the elastic restoring force of the elastic member 4 to block the connection between the first interface 12 and the second interface 13, thereby cutting off the flow of the medium.

[0043] It can be understood that the check valve is in the initial state when the medium pressure of the medium flowing into the first interface 12 is less than the pressure of the elastic member 4 pressing down the valve core 3 or the check valve is in the state where no medium flows into the first interface 12.

[0044] As shown in Figure 3, optionally, when the first interface 12 and the second interface 13 are in communication, the valve core 3 is lifted in a first direction, sealing the working chamber 11 to form a sealed chamber. When the medium flows between the first interface 12 and the second interface 13, the working chamber 11 becomes a sealed chamber. That is, the space where the elastic member 4 is located is not connected to the first interface 12 and the second interface 13, ensuring that the flowing medium does not come into contact with the elastic member 4, eliminating the risk of the medium corroding the elastic member 4 and ensuring the service life of the elastic member 4. At the same time, the elastic member 4 is hidden within the working chamber 11, essentially isolated from external moisture, thereby extending the service life of the elastic member 4.

[0045] Optionally, the elastic member 4 is configured as a coil spring. When compressed, the coil spring can better store energy, ensuring that the preload pressure provided by the coil spring to the valve core 3 remains stable, thereby ensuring the stability and reliability of the opening and closing pressure of the check valve of this embodiment. As an alternative to the above technical solution, the elastic member 4 is configured as a disc spring. Disc springs can store a large amount of energy when compressed to a smaller deformation amount, and are more suitable for the smaller space along the first direction of the working chamber 11 of the check valve of this embodiment. As another alternative to the above technical solution, the elastic member 4 is configured as a wave spring.

[0046] As shown in Figures 1 and 2, optionally, a connecting rod 22 is coaxially protruded from the bottom of the valve stem 2. The cross-sectional area of ​​the connecting rod 22 perpendicular to the first direction is smaller than the cross-sectional area of ​​the valve stem 2 perpendicular to the first direction. The connecting rod 22 is disposed within the working chamber 11. The top end of the elastic member 4 is sleeved outside the connecting rod 22, and the top end surface of the elastic member 4 abuts the bottom end surface of the valve stem 2. The connecting rod 22 limits and guides the elastic member 4, so that when the valve stem 2 is driven to rotate within the mounting hole for lifting and lowering adjustment, the elastic member 4 is linearly compressed or reset along the first direction, thereby improving the accuracy of the opening and closing pressure adjustment of the check valve of this embodiment. This is particularly suitable for use in environments where high precision in opening and closing pressure is required.

[0047] As shown in Figures 1 and 3, the top surface of the valve core 3 is optionally provided with a mounting groove 31, and the bottom end of the elastic member 4 is embedded in the mounting groove 31, with the bottom end surface of the elastic member 4 abutting the inner bottom wall of the mounting groove 31. The mounting groove 31 limits and guides the bottom of the elastic member 4, so that when the valve stem 2 is driven to rotate within the mounting hole for lifting and lowering adjustment, the elastic member 4 is linearly compressed or reset along the first direction, thereby improving the accuracy of the opening and closing pressure adjustment of the check valve of this embodiment, and is particularly suitable for use in environments with high requirements for opening and closing pressure accuracy. At the same time, the mounting groove 31 can provide a clearance space for the connecting rod 22, increasing the space for the connecting rod 22 to descend along the first direction, thereby increasing the upper limit of the compression amount of the steplessly adjustable elastic member 4, thereby more flexibly adjusting the opening and closing pressure of this embodiment, and enhancing adaptability.

[0048] As shown in FIG2 , optionally, an anti-slip pad 23 is provided between the bottom end face of the valve stem 2 and the top end face of the elastic member 4. The anti-slip pad 23 is sleeved outside the connecting rod 22, and the cross-sectional area of ​​the anti-slip pad 23 perpendicular to the first direction is larger than the cross-sectional area of ​​the valve stem 2 perpendicular to the first direction. The anti-slip pad 23 increases the contact area with the top end face of the elastic member 4 and increases the friction between the anti-slip pad 23 and the top end face of the elastic member 4, so that when the valve stem 2 is driven to rotate in the mounting hole for lifting and lowering adjustment, the elastic member 4 is not easily offset perpendicular to the first direction, ensuring that the elastic member 4 is compressed or reset in a straight line along the first direction, thereby improving the accuracy of the opening and closing pressure adjustment of the check valve of this embodiment.

[0049] As shown in FIG2 , optionally, a sliding groove 51 is recessed in the top wall of the working chamber 11. The sliding groove 51 is concentrically arranged with the mounting hole and communicates with the mounting hole. The anti-slip pad 23 is slidably arranged in the sliding groove 51 along a first direction. The anti-slip pad 23 is limited and guided by the sliding groove 51, so that when the valve stem 2 is driven to rotate in the mounting hole for lifting and lowering adjustment, the anti-slip pad 23 is lifted and lowered linearly along the first direction, ensuring that the elastic member 4 is compressed or reset linearly along the first direction, thereby improving the accuracy of the opening and closing pressure adjustment of the check valve of this embodiment.

[0050] As shown in FIG1 , the mounting hole is optionally configured as a stepped hole, and one end of the mounting hole facing away from the working chamber 11 along the first direction is configured as a large-diameter hole. A sealing filler 61 is provided between the inner wall of the large-diameter hole and the outer wall of the valve stem 2; the internal threaded portion is provided on the inner wall of the small-diameter hole of the mounting hole. The sealing filler 61 is used to fill and seal the space between the outer wall of the portion of the valve stem 2 located within the large-diameter hole and the inner wall of the large-diameter hole. On the one hand, this can better isolate the working chamber 11 from the outside world, ensure that the elastic member 4 is fully isolated from external moisture, and improve the service life of the elastic member 4; on the other hand, it can prevent external particles from entering the mounting hole, reduce wear on the valve stem 2, and extend the service life of the valve stem 2.

[0051] As shown in FIG1 , the valve stem 2 is optionally provided with a gasket 62 on its outer sleeve, the top end of the gasket 62 abutting against the bottom end of the sealing packing 61, and the bottom end of the gasket 62 abutting against the inner bottom wall of the large-diameter hole; the top end of the external threaded portion 21 is located within the gasket 62. By providing a space for accommodating the top end of the external threaded portion 21, when the valve stem 2 is driven to rotate in the mounting hole for lifting and lowering adjustment, the contact and friction between the external threaded portion 21 and the sealing packing 61, which may cause wear of the sealing packing 61, can be avoided, thereby extending the service life of the sealing packing 61.

[0052] Optionally, the end face of the sealing packing 61 facing away from the small-diameter hole of the mounting hole abuts a press sleeve 63. The end of the press sleeve 63 facing away from the sealing packing 61 abuts a pressure plate 64. The pressure plate 64 is detachably connected to the top end of the valve body 1. A through-hole is formed through the pressure plate 64 along a first direction, through which the valve stem 2 slides in the first direction. The pressure plate 64 restricts the freedom of movement of the sealing packing 61 away from the working chamber 11, ensuring that the sealing packing 61 is tightly packed within the large-diameter hole of the mounting hole, thereby effectively sealing the gap between the outer wall of the portion of the valve stem 2 located within the large-diameter hole and the inner wall of the large-diameter hole. The through-hole in the pressure plate 64 also increases the contact guide area for the valve stem 2 to rise and fall in the first direction, thereby improving the stability of the valve stem 2's rise and fall. The pressure plate 64 is also detachably connected to the top end of the valve body 1, allowing the pressure plate 64 and valve body 1 to be manufactured and disassembled separately.

[0053] Optionally, the top end of the working chamber 11 extends through the valve body 1 in a first direction. A valve cover 5 is detachably connected to the top end of the valve body 1. The valve cover 5 covers the working chamber 11, and the mounting hole is provided through the valve cover 5 in the first direction. The detachable connection of the valve cover 5 to the top end of the valve body 1 facilitates assembly of the valve cover 5 after assembling components such as the valve core 3 and the elastic member 4 within the working chamber 11. This facilitates separation of the valve cover 5 from the valve body 1 for maintenance. Specifically, the pressure plate 64 is detachably connected to the top end of the valve cover 5, and the sliding groove 51 is recessed in the bottom end surface of the valve cover 5.

[0054] In order to further improve the sealing performance of the abutment between the top end surface of the valve body 1 and the bottom end surface of the valve cover 5 , optionally, a spiral wound gasket 52 is provided between the bottom end surface of the valve cover 5 and the top end surface of the valve body 1 .

[0055] This embodiment does not impose any restrictions on the detachable connection structure between the valve body 1 and the valve cover 5. In this embodiment, while ensuring the tightness of the connection between the valve body 1 and the valve cover 5, the convenience of assembling and disassembling the two is improved. Optionally, the top surface of the valve body 1 is provided with a first internal threaded hole, and the valve cover 5 is provided with a first through-hole at a position corresponding to the first internal threaded hole. The first through-hole penetrates the valve cover 5 along a first direction. During assembly, the first fastening bolt 53 passes through the first through-hole and is threadedly connected to the first internal threaded hole. Of course, this is only an optional implementation of the detachable connection structure between the valve body 1 and the valve cover 5. In another alternative embodiment, the top surface of the valve body 1 is provided with a first nut, and the valve cover 5 is provided with a first through-hole at a position corresponding to the first nut. The first through-hole penetrates the valve cover 5 along a first direction. During assembly, the first fastening bolt 53 passes through the first through-hole and is threadedly connected to the first nut.

[0056] This embodiment does not limit the detachable connection structure between the pressure plate 64 and the valve cover 5. In this embodiment, while ensuring the tightness of the connection between the pressure plate 64 and the valve cover 5, the convenience of assembling and disassembling the two is improved. Optionally, the top surface of the valve cover 5 is provided with a second internal threaded hole, and a second through-hole is provided on the pressure plate 64 at a position corresponding to the second internal threaded hole. The second through-hole passes through the pressure plate 64 along the first direction. During assembly, the second fastening bolt 65 passes through the second through-hole and is threadedly connected to the second internal threaded hole. Of course, this is only an optional implementation of the detachable connection structure between the pressure plate 64 and the valve cover 5. In another alternative embodiment, the top surface of the valve cover 5 is provided with a second nut, and a second through-hole is provided on the pressure plate 64 at a position corresponding to the second nut. The second through-hole passes through the pressure plate 64 along the first direction. During assembly, the second fastening bolt 65 passes through the second through-hole and is threadedly connected to the second nut.

[0057] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of this application.

Claims

1. A check valve with adjustable opening and closing pressure, characterized in that: include: A valve body (1) is provided with a working chamber (11) therein, and a first interface (12) and a second interface (13) are respectively provided on both sides of the valve body (1) for connecting an external pipeline with the working chamber (11); a mounting hole is connected to the top of the working chamber (11) along a first direction, and an inner wall of the mounting hole is provided with an internal threaded portion; A valve stem (2) is movably arranged in the mounting hole along a first direction, and an outer wall thereof is provided with an external threaded portion (21), wherein the external threaded portion (21) is threadedly connected to the internal threaded portion; A valve core (3) is arranged in the working chamber (11) so as to slide along a first direction, and an elastic member (4) is provided between the top of the valve core (3) and the bottom of the valve stem (2); when the check valve is in an initial state, the valve core (3) blocks the connection between the first interface (12) and the second interface (13).

2. The check valve with adjustable opening and closing pressure according to claim 1, characterized in that: When the first interface (12) and the second interface (13) are in a connected state, the valve core (3) is lifted along a first direction and blocks the working chamber (11) to form a sealed chamber.

3. The check valve with adjustable opening and closing pressure according to claim 1 or 2, characterized in that: The elastic member (4) is configured as one of a coil spring, a disc spring or a wave spring.

4. The check valve with adjustable opening and closing pressure according to claim 1, characterized in that: A connecting rod (22) is coaxially protruded from the bottom of the valve stem (2), and the cross-sectional area of ​​the connecting rod (22) perpendicular to the first direction is smaller than the cross-sectional area of ​​the valve stem (2) perpendicular to the first direction. The connecting rod (22) is arranged in the working chamber (11); the top end of the elastic member (4) is sleeved outside the connecting rod (22), and the top end surface of the elastic member (4) abuts against the bottom end surface of the valve stem (2).

5. The check valve with adjustable opening and closing pressure according to claim 1 or 4, characterized in that: The top end surface of the valve core (3) is provided with a mounting groove (31), the bottom end of the elastic member (4) is embedded in the mounting groove (31), and the bottom end surface of the elastic member (4) abuts against the inner bottom wall of the mounting groove (31).

6. The check valve with adjustable opening and closing pressure according to claim 4, characterized in that: An anti-slip pad (23) is provided between the bottom end surface of the valve stem (2) and the top end surface of the elastic member (4), and the anti-slip pad (23) is sleeved outside the connecting rod (22). The cross-sectional area of ​​the anti-slip pad (23) perpendicular to the first direction is larger than the cross-sectional area of ​​the valve stem (2) perpendicular to the first direction.

7. The check valve with adjustable opening and closing pressure according to claim 6, characterized in that: A sliding groove (51) is recessed on the top wall of the working chamber (11), and the sliding groove (51) is concentrically arranged with the mounting hole and communicated with the mounting hole; the anti-slip pad (23) is slidably arranged in the sliding groove (51) along a first direction.

8. The check valve with adjustable opening and closing pressure according to claim 1 or 7, characterized in that: The mounting hole is configured as a stepped hole, and one end of the mounting hole away from the working chamber (11) along the first direction is configured as a large-diameter hole, and a sealing filler (61) is provided between the inner wall of the large-diameter hole and the outer wall of the valve stem (2); the internal thread portion is provided on the inner wall of the small-diameter hole of the mounting hole.

9. The check valve with adjustable opening and closing pressure according to claim 8, characterized in that: The valve stem (2) is provided with a gasket (62) on its outer sleeve, one end of the gasket (62) abuts against the bottom end surface of the sealing filler (61), and the other end of the gasket (62) abuts against the inner bottom wall of the large-diameter hole; the top end of the external threaded portion (21) is located inside the gasket (62); And / or, the end face of the small-diameter hole of the sealing filler (61) facing away from the mounting hole is abutted against a pressing sleeve (63), and one end of the pressing sleeve (63) facing away from the sealing filler (61) is abutted against a pressing plate (64), The pressure plate (64) is detachably connected to the top end of the valve body (1); a through hole is formed on the pressure plate (64) along a first direction, and the valve stem (2) slides through the through hole along the first direction; And / or, the top end of the working chamber (11) passes through the valve body (1) along the first direction, the top end of the valve body (1) is detachably connected to a valve cover (5), the valve cover (5) covers the working chamber (11), and the mounting hole is provided on the valve cover (5) along the first direction.

10. The check valve with adjustable opening and closing pressure according to claim 9, characterized in that: A wound gasket (52) is provided between the bottom end surface of the valve cover (5) and the top end surface of the valve body (1); And / or, a first internal threaded hole is provided on the top surface of the valve body (1), a first through hole is provided on the valve cover (5) at a position corresponding to the first internal threaded hole, and the first through hole passes through the valve cover (5) along a first direction; during assembly, a first fastening bolt (53) passes through the first through hole and is threadedly connected to the first internal threaded hole; And / or, a second internal threaded hole is provided on the top surface of the valve cover (5), a second through-hole is provided on the pressure plate (64) at a position corresponding to the second internal threaded hole, and the second through-hole passes through the pressure plate (64) along the first direction; during assembly, a second fastening bolt (65) passes through the second through-hole and is threadedly connected in the second internal threaded hole.

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