Double-diaphragm type pneumatic two-way valve

Abstract

The invention discloses a double-diaphragm type pneumatic two-way valve which comprises a valve body, a top cover, a bottom cover, a valve seat and a valve rod. A hollow cavity is formed in the valve body, and a medium inlet and a medium outlet which communicate with the hollow cavity are formed in the two sides of the valve body. The bottom end of the top cover is fixedly connected with the top end of the valve body; the top end of the bottom cover is fixedly connected with the bottom end of the valve body; the valve seat is located in the hollow cavity, the valve seat is fixedly connected with the valve body, and a medium channel is formed in the valve seat; the bottom end of the valve rod penetrates through the medium channel, a membrane A, a valve plate and a membrane B are sequentially fixed to the valve rod from top to bottom, the membrane A is connected between the valve body and the top cover in a sealed mode, the membrane B is connected between the valve body and the bottom cover in a sealed mode, and the valve plate is located between the medium channel and the membrane B. The diaphragm deforms to drive the valve rod to work through pressure difference, friction can be reduced, the driving efficiency is improved, part abrasion is reduced, and the service life of the valve is prolonged.

Description

Technical Field

[0001] This invention relates to the field of valve technology, and in particular to a double diaphragm differential two-way valve. Background Technology

[0002] Valves, as key control components in fluid transmission systems, are widely used in diverse fields such as liquefied petroleum gas, medical equipment, biopharmaceuticals, food and beverage, new energy, and semiconductor manufacturing.

[0003] Existing valves mainly include ball valves, angle valves, butterfly valves, and gate valves. Among them, ball valves, butterfly valves, and gate valves all require pneumatic actuators (generally referred to as cylinders) to generate the force and torque required for valve operation. The combined volume of these two parts is relatively large, which is not space-efficient. Furthermore, the piston inside the cylinder is a sliding seal, which results in energy loss due to frictional resistance, leading to reduced driving efficiency. Cylinder seal failure often causes the valve to stop operating. The valve packing also increases friction and potential failure points, requiring frequent maintenance and packing replacement. In ball valves and gate valves, the ball plate is in close contact with the valve seat during operation, generating friction that reduces transmission efficiency and also weakens the protection against small particulate impurities in the medium. Once impurities get stuck in the relatively sliding contact surface, they will damage the sealing surface and cause jamming. Angle valves and butterfly valves do not have self-adaptive capabilities and need to rely on the force of springs and cylinders to seal or open the high pressure differential medium channel. They cannot adaptively adjust the sealing force according to the pressure difference between the medium inlet and outlet. The valve's seal must be effective at the highest operating pressure difference at both ends of the valve under any pressure differential condition, resulting in wasted driving energy, high stress at the parts mating, and easy damage to the parts. Solenoid valves cannot be used in large-diameter full-bore valves because the working air gap of the electromagnet is directly related to the stroke of the valve internals, and the larger the air gap, the greater the required coil power, the greater the heat generation, and the exponential increase in energy consumption.

[0004] Therefore, there is an urgent need for a cylinder and valve combination that reduces friction, uses pressure difference to move the valve plate, and can be applied to a large-diameter dual-plate differential two-way valve. Summary of the Invention

[0005] The purpose of this invention is to provide a dual-panel differential two-way valve to solve the above-mentioned problems in the prior art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A dual-plate differential two-way valve includes a valve body, a top cover, a bottom cover, a valve seat, and a valve stem. The valve body has a hollow cavity, and the valve body has a medium inlet and a medium outlet on both sides that communicate with the hollow cavity; The bottom end of the top cover is fixedly connected to the top end of the valve body, and an air port A is provided on the top cover; The top end of the bottom cover is fixedly connected to the bottom end of the valve body, and an air port B is provided on the bottom cover; The valve seat is located in the hollow cavity, and the valve seat is fixedly connected to the valve body. A medium channel is provided on the valve seat. The bottom end of the valve stem passes through the medium channel. The valve stem is fixed with diaphragm A, valve plate and diaphragm B in sequence from top to bottom. Diaphragm A is sealed between the valve body and the top cover. Diaphragm B is sealed between the valve body and the bottom cover. The valve plate is located between the medium channel and diaphragm B.

[0007] Furthermore, the materials of diaphragm A and diaphragm B are selected from rubber, metal, polymer, and composite materials.

[0008] Furthermore, the equivalent force-bearing area of ​​the diaphragm A is greater than the force-bearing area of ​​the valve plate.

[0009] In this invention, when the pressure on diaphragm A and valve plate are equal, the resultant force is upward. As the medium pressure increases, the upward resultant force also increases; as the medium pressure decreases, the upward resultant force also decreases. Under high pressure differential, the sealing force between valve plate and medium channel can be improved; under low pressure differential, the sealing force can be reduced to adapt to the different sealing forces required under different medium pressures. This reduces the stress on the sealing ring on valve plate and increases the lifespan of the sealing ring.

[0010] Furthermore, the valve seat has a right-angled triangle vertical cross-section, the vertical portion of the valve seat is located near the medium outlet, the end of the vertical portion of the valve seat is fixedly connected to the valve body at the top of the medium outlet, the end of the horizontal portion of the valve seat is fixedly connected to the valve body at the bottom of the medium inlet, and the medium channel is located in the horizontal portion of the valve seat.

[0011] Furthermore, a sealing ring is provided at the top of the valve plate.

[0012] Furthermore, the sealing ring is made of one of the following materials: synthetic rubber, polymer material, metal, graphite, and asbestos.

[0013] Furthermore, the top cover is fixedly connected to the top of the valve body by bolts, and the bottom cover is fixedly connected to the bottom of the valve body by bolts.

[0014] Furthermore, annular grooves are provided at both the top and bottom of the valve body, and O-rings are provided in the annular grooves.

[0015] Furthermore, both the top and bottom ends of the diaphragm A and the diaphragm B are provided with pads.

[0016] Furthermore, the medium inlet, the medium outlet, and the medium channel constitute a medium flow channel. When the top of the valve plate abuts against the valve seat, the medium flow channel is cut off; when the valve plate separates from the valve seat, the medium flow channel is opened.

[0017] The present invention discloses the following technical effects: 1. This invention replaces fillers and sealing rings with deformable diaphragms that generate friction during movement, transforming friction into a force that overcomes the rigidity of the diaphragm during deformation, thus greatly reducing motion resistance and improving drive efficiency.

[0018] 2. By using a deformable diaphragm, this invention avoids friction. Without friction, wear on parts is effectively reduced, maintenance frequency is decreased, and valve service life is increased.

[0019] 3. In this invention, the diaphragm is compressed and sealed, and there is no relative movement between it and the sealing surface during the movement, which will not cause seal wear and minor leakage. Therefore, the risk of seal failure is reduced and the maintenance frequency is reduced.

[0020] 4. This invention integrates a pneumatic actuator into a valve by utilizing the design of a diaphragm, valve plate, and air port, thereby reducing the size of the valve.

[0021] 5. This invention operates based on pressure difference, and the valve can be driven by a constant air source pressure through the design of the diaphragm and valve plate dimensions, thus allowing for larger valve diameters; because the shape and size of the diaphragm can be designed, it can meet the full-bore flow requirements of various diameters. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 : A schematic diagram of a double-diaphragm pneumatic two-way valve according to the present invention; Figure 2 This invention provides a schematic diagram of the valve body and seat structure of a double-diaphragm pneumatic two-way valve. Figure 3 : A schematic diagram of the valve stem structure of a double diaphragm pneumatic two-way valve according to the present invention; Figure 4 : A schematic diagram of the closed state structure of a double-diaphragm pneumatic two-way valve according to the present invention; Figure 5: A schematic diagram of the open state structure of a double diaphragm pneumatic two-way valve according to the present invention; Figure 6 : Diagram of veneer installation method; Specifically, the components are: 1. Valve body; 2. Top cover; 3. Bottom cover; 4. Air port A; 5. Diaphragm A; 6. Air port B; 7. Diaphragm B; 8. Valve stem; 9. Valve plate; 10. Medium inlet; 11. Medium outlet; 12. Valve seat; 13. Chamber A; 14. Chamber B; 15. Slot; 16. Medium passage; 17. Hollow cavity; 18. Sealing ring; 19. Gasket; 20. Screw. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] The specific implementation method is as follows: like Figures 1-5 As shown; this invention discloses a double-diaphragm pneumatic two-way valve, including a valve body 1, a top cover 2, a bottom cover 3, a valve seat 12, and a valve stem 8. A hollow cavity 17 is provided inside the valve body 1, and a medium inlet 10 and a medium outlet 11 communicating with the hollow cavity 17 are provided on both sides of the valve body 1. The bottom end of the top cover 2 is fixedly connected to the top end of the valve body 1, and an air port A4 is provided on the top cover 2; The top of the bottom cover 3 is fixedly connected to the bottom of the valve body 1, and an air port B6 is provided on the bottom cover 3; Valve seat 12 is located inside hollow cavity 17. Valve seat 12 is integrally connected with valve body 1. Medium passage 16 is provided on valve seat 12. The bottom end of the valve stem 8 passes through the medium channel 16. The valve stem 8 is fixed with diaphragm A5, valve plate 9 and diaphragm B7 from top to bottom. Diaphragm A5 is sealed between valve body 1 and top cover 2. Diaphragm B7 is sealed between valve body 1 and bottom cover 3. Valve plate 9 is located between medium channel 16 and diaphragm B7.

[0027] In this invention, diaphragms A5 and B7 are fixed at both ends of valve stem 8. Top cover 2 and diaphragm A5 form chamber A13, and bottom cover 3 and diaphragm B7 form chamber B14. Chambers A13 and B14 are two independent chambers. The pressure difference between chambers A13 and B14 is controlled by controlling the air intake and exhaust of air ports A4 and B6, thereby driving the valve stem 8 to move up and down, thus realizing the closing and opening of valve plate 9 and valve seat 12.

[0028] In this invention, the pneumatic structure and valve body 1 are integrated into one structure. This design reduces the air chamber space, saves the volume of the driving compressed gas, and reduces the burden on the compressor.

[0029] Since the technical solution of the present invention relies on pressure difference to work, and the valve can be driven by the air source pressure within a constant range through the size design of the diaphragm and valve plate 9, the valve diameter can be made larger.

[0030] In this invention, the valve plate 9 moves vertically against the bottom of the valve seat 12, generating only extrusion force and no friction force, which improves the reliability of the seal. At the same time, the sealing ring 18 on the valve plate 9 also has a limiting function. Within a certain degree of wear, the sealing stroke will change slightly until the sealing element is tightly against the cover. Therefore, the sealing effect can still be maintained within a certain wear range. Moreover, it improves the resistance to impurities and particulate media. Even if impurities and particles are stuck, the medium can be flushed away by opening and closing the valve to restore the normal sealing state.

[0031] In this embodiment, a control element is provided to control the opening and closing of the valve, and the surface mounting method is as follows: Figure 6 As shown, specifically, a component mounting plane is made on the valve body 1 and a threaded hole is opened. A pressure control component with a face-to-face connection is used. Two gas passages are connected to chambers A13 and B14 in the housing part of the valve body 1. The component is fixed to the valve by bolts passing through the threaded hole.

[0032] In this embodiment, the valve is connected to the external media pipelines on both sides by thread, flange, or clamp.

[0033] In this embodiment, diaphragm A5 and diaphragm B7 can be flat diaphragms or diaphragms with various curves as generatrices. They are not limited to being made of rubber, metal, polymer, or composite materials; any deformable material can be used.

[0034] In this invention, the dimensions of diaphragm A5, diaphragm B7, valve stem 8, and valve plate 9 are designed to achieve the required differential pressure for actuation. For example, the valve can still open and close normally even when the pressure difference between the gas source and the medium is 1:3 or even 1:n. Since the dimensions can be designed as needed, the flow requirements of various diameters can be met.

[0035] In other embodiments, diaphragm A5 and diaphragm B7 may be replaced by pistons.

[0036] In this embodiment, the equivalent force-bearing area of ​​diaphragm A5 is greater than the force-bearing area of ​​valve plate 9.

[0037] In this embodiment, a sealing ring 18 is provided at the top of the valve plate 9; its sealing material is composed of various synthetic rubbers, polymer materials, metals, graphite, asbestos, various composite materials and other sealing materials. The sealing ring 18 can also be replaced with flow regulating components with different flow curves.

[0038] In this invention, the sealing force is changed by the medium pressure difference when the pressure difference changes. Specifically, the equivalent force-bearing area of ​​diaphragm A5 is greater than that of valve plate 9. When the pressure on diaphragm A5 and valve plate 9 is equal, the resultant force is upward. As the medium pressure increases, the upward resultant force also increases. As the medium pressure decreases, the upward resultant force also decreases. Under high pressure difference, diaphragm A5 rises and simultaneously drives valve stem 8 and valve plate 9 to move upward, which can improve the sealing force between valve plate 9 and medium channel 16. Under low pressure difference, the upward force decreases, which can reduce the sealing force. This allows it to adapt to different sealing forces required under different medium pressures, reduce the force on sealing ring 18 on valve plate 9, and increase the life of sealing ring 18.

[0039] In this embodiment, as Figure 2 As shown, the vertical section of the valve seat 12 is a right triangle. The vertical part of the valve seat 12 is located near the medium outlet 11. The end of the vertical part of the valve seat 12 is fixedly connected to the valve body 1 at the top of the medium outlet 11. The end of the horizontal part of the valve seat 12 is fixedly connected to the valve body 1 at the bottom of the medium inlet 10. The medium channel 16 is located in the horizontal part of the valve seat 12.

[0040] In this embodiment, the sealing ring 18 is made of one of the following materials: synthetic rubber, polymer material, metal, graphite, and asbestos.

[0041] In this embodiment, the top cover 2 is fixedly connected to the top of the valve body 1 by bolts, and the bottom cover 3 is fixedly connected to the bottom of the valve body 1 by bolts.

[0042] In this embodiment, annular grooves 15 are provided at both the top and bottom of the valve body 1, and O-rings are provided in the annular grooves 15.

[0043] In this invention, diaphragms A5 and B7 are compressed and sealed, respectively between the top cover 2 and the valve body 1, and between the bottom cover 3 and the valve body 1. O-rings are provided between diaphragms A5 and B7 and the valve body 1. During the movement, there is no relative movement between them and the sealing surface, which will not cause seal wear and minor leakage. Therefore, the risk of seal failure is reduced, and no packing is needed for sealing, reducing the maintenance frequency. At the same time, due to the compression seal, the movement of the valve stem 8 will not create gaps between diaphragms A5 or B7 and the valve body 1, top cover 2, and bottom cover 3, thus preventing adhesion leakage.

[0044] Adhesive leakage refers to a situation where a small amount of the medium adheres to the sealing contact surface, and may be exposed outside the sealed cavity after the sealing contact surface moves.

[0045] In this embodiment, both the top and bottom ends of diaphragms A5 and B7 are provided with pads 19. Specifically, screws 20 pass through pads 19, diaphragm A5, and pads 19 in sequence and are threaded to the top end of valve stem 8. Screws 20 pass through pads 19, diaphragm B7, and pads 19 in sequence and are threaded to the bottom end of valve stem 8, thereby pressing and fixing diaphragms A and B between the head of screws 20 and valve stem.

[0046] In this embodiment, the medium inlet 10, the medium outlet 11, and the medium channel 16 constitute a medium flow channel. When the top of the valve plate 9 abuts against the valve seat 12, the medium flow channel is cut off; when the valve plate 9 separates from the valve seat 12, the medium flow channel is opened.

[0047] In other embodiments, the valve stem 8 can be extended to break through the upper and lower valve covers, transmitting the mechanical movement of the internal valve core to the outside of the housing, providing a detection point and force point for the stroke detection and manual operation device. When the valve stem 8 passes through the valve cover, the contact surface between the valve cover and the valve stem 8 can be sealed with a sealing ring 18 according to the valve usage method, ensuring that the air port A4 and air port B6 are the only openings of the chambers A13 and B14, so as to prevent the valve from malfunctioning due to leakage of driving pressure.

[0048] The working principle of a double diaphragm pneumatic two-way valve of the present invention: Specifically, in this embodiment, the valve operates in three states: closed, intermediate, and open.

[0049] When the valve is closed Figure 4 As shown, chambers A13 and B14 are both connected to external gas pipelines. The medium enters the valve body through the medium inlet 10. The diaphragm A5 is pushed upward by the medium, and the valve plate 9 is pushed downward by the medium pressure. These two forces act on the valve stem 8 in an upward direction. The diaphragm B7 is subjected to the same force, so that when closed, the resultant force is upward, causing the valve plate 9 to abut against the valve seat 12, thus cutting off the medium flow channel. Furthermore, the higher the pressure difference across the medium, the greater the resultant force on the valve plate 9, enhancing the sealing force.

[0050] Intermediate opening process: The pressure difference between chamber A13 and chamber B14 is increased through air port A4. The diaphragm A5 is subjected to downward pressure, and the combined force of the valve plate 9 and diaphragm B7 is downward. The valve stem 8 and valve plate 9 move downward to open the valve.

[0051] When the valve is open Figure 5 As shown, valve plate 9 opens the medium channel, reducing the pressure difference between the upper and lower parts of valve plate 9. The magnitude of the resultant force changes, but the direction remains downward, maintaining the open state.

[0052] Intermediate closing process: Release the pressure in chamber A13 to atmospheric pressure level, increase the pressure in chamber B14 through air port B6, lift diaphragm B7, and diaphragm A5 is subjected to an upward force under the medium pressure. After calculating the forces on valve plate 9 and diaphragm B7, the resultant force is upward, causing valve plate 9 to move upward and close the medium passage.

[0053] Adjustment state: The pressure difference between chamber A13 and chamber B14 can be changed to stop the valve plate 9 at any open or closed position, thereby adjusting the degree of valve opening. With different shapes of valve plates 9, various flow curves of the valve can be realized (e.g., the flow rate changes linearly with the opening degree, changes exponentially, changes from large to small and then increases again, etc.).

[0054] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0055] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0056] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A double-diaphragm pneumatic two-way valve, characterized in that: include Valve body (1), a hollow cavity (17) is provided inside the valve body (1), and a medium inlet (10) and a medium outlet (11) communicating with the hollow cavity (17) are provided on both sides of the valve body (1). Top cover (2), the bottom end of the top cover (2) is fixedly connected to the top end of the valve body (1), and an air port A (4) is opened on the top cover (2). Bottom cover (3), the top of the bottom cover (3) is fixedly connected to the bottom of the valve body (1), and an air port B (6) is provided on the bottom cover (3). Valve seat (12), the valve seat (12) is located inside the hollow cavity (17), the valve seat (12) is fixedly connected to the valve body (1), and a medium channel (16) is provided on the valve seat (12). The valve stem (8) has its bottom end passing through the medium channel (16). The valve stem (8) is fixed with a diaphragm A (5), a valve plate (9), and a diaphragm B (7) from top to bottom. The diaphragm A (5) is sealed between the valve body (1) and the top cover (2). The diaphragm B (7) is sealed between the valve body (1) and the bottom cover (3). The valve plate (9) is located between the medium channel (16) and the diaphragm B (7).

2. The double-diaphragm pneumatic two-way valve according to claim 1, characterized in that: The materials of the diaphragm A (5) and the diaphragm B (7) are selected from rubber, metal, polymer, and composite materials.

3. The double-diaphragm pneumatic two-way valve according to claim 1, characterized in that: The equivalent force-bearing area of ​​the diaphragm A (5) is greater than the force-bearing area of ​​the valve plate (9).

4. The double-diaphragm pneumatic two-way valve according to claim 1, characterized in that: The vertical cross section of the valve seat (12) is a right triangle. The vertical part of the valve seat (12) is located close to the medium outlet (11). The end of the vertical part of the valve seat (12) is fixedly connected to the valve body (1) at the top of the medium outlet (11). The end of the horizontal part of the valve seat (12) is fixedly connected to the valve body (1) at the bottom of the medium inlet (10). The medium channel (16) is located in the horizontal part of the valve seat (12).

5. A double-diaphragm pneumatic two-way valve according to claim 1, characterized in that: The valve plate (9) is provided with a sealing ring (18) at its top.

6. The double-diaphragm pneumatic two-way valve according to claim 1, characterized in that: The top cover (2) is fixedly connected to the top of the valve body (1) by bolts; the bottom cover (3) is fixedly connected to the bottom of the valve body (1) by bolts.

7. A double-diaphragm pneumatic two-way valve according to claim 6, characterized in that: The valve body (1) has an annular groove (15) at both the top and bottom, and an O-ring seal is provided in the annular groove (15).

8. A double-diaphragm pneumatic two-way valve according to claim 1, characterized in that: The top and bottom ends of the diaphragm A (5) and diaphragm B (7) are provided with pads (19).

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