A pneumatically operated valve

Abstract

This application belongs to the field of valve technology and discloses a pneumatically controlled valve, including: a valve seat, a connecting seat, a valve core, a cylinder, a sealing cover, a valve stem, a piston, a locking nut, a fixed seat, and an air intake control rotary seat; a connecting seat is fixedly mounted on the valve seat; a cylinder is fixedly mounted on the connecting seat; a sealing cover is fixedly mounted on the upper end of the cylinder; a valve core is disposed inside the valve seat; a valve stem is disposed on the valve core; a piston is disposed on the upper end of the valve stem; a return spring is disposed above the piston; connecting pipes are symmetrically fixedly mounted on both sides; flanges are fixedly mounted on the connecting pipes; air pipe A and air pipe B are fixedly mounted on the cylinder; a fixed seat is fixedly mounted on the cylinder, and an air intake control rotary seat is rotatably mounted on the fixed seat. This invention achieves bidirectional, non-differential adaptation, completely avoiding the risk of reverse connection: no directional restrictions, lowering the operation threshold, avoiding safety accidents, and improving the installation error tolerance rate; multiple sealing designs achieve zero leakage and impact protection, extending its service life.

Description

Technical Field

[0001] This application relates to the field of valve technology, and more specifically, to a pneumatically controlled valve. Background Technology

[0002] Pneumatic angle seat valves are widely used for frequent short-term starts, characterized by their sensitive response and accurate action. When used in conjunction with solenoid valves, pneumatic control can accurately control the flow rate of gas and liquid. When controlling liquid flow, the valve stem in the pneumatic angle seat valve actuates, and its sealing ring contacts the valve seat, achieving a liquid blockage effect and thus controlling the liquid flow.

[0003] Existing technology publication CN109027261B provides a pneumatic angle seat valve, including a valve body, a stuffing box, a return spring, a pneumatic control head, an indicator, an air inlet, and a valve stem. The indicator is located at the top of the pneumatic control head, which contains an air chamber and an air inlet communicating with the air chamber. A piston mounted on the valve stem is located in the air chamber. A stuffing box is placed between the valve body and the pneumatic control head. The return spring is located in the air chamber, and its lower end is connected to the piston. The lower end of the valve stem is located in the valve body and is connected to a cylinder plug. The cylinder plug includes a cylinder body, a threaded blind hole on the cylinder body connected to the valve stem, a sealing ring mounting platform on the cylinder body, a sealing ring, and a clamping device for pressing the sealing ring onto the sealing ring mounting platform. The sealing ring and the threaded blind hole are coaxially aligned. This invention provides good liquid blocking effect and good valve control performance.

[0004] While the existing technical solutions described above can achieve the relevant beneficial effects through their structure, they still have the following drawbacks: 1. The flow channel structure of existing traditional angle seat valves is asymmetrical, with a clear and fixed distinction between the inlet and outlet pipes. During installation, it is necessary to manually and accurately determine the direction of medium flow and connect the corresponding pipes. Reversing the connection directly causes functional failure, ranging from increased medium flow resistance and abnormal flow to damage to the valve's sealing structure, resulting in leakage. This requires disassembly and reinstallation, significantly reducing on-site construction efficiency. Once the inlet and outlet pipes are reversed, it not only affects the function but also poses a serious safety hazard. 2. The closing force of existing traditional angle seat valves mostly relies on a single return spring. Long-term use can easily lead to sealing failure. The spring will gradually lose elasticity due to long-term compression. Insufficient elasticity will prevent the valve core from tightly fitting the valve seat, directly causing leakage. Regular spring replacement is required, resulting in high maintenance costs. In view of this, we propose a pneumatically controlled valve and method. Summary of the Invention

[0005] 1. The technical problems to be solved.

[0006] The purpose of this application is to provide a pneumatic control valve that solves the technical problems mentioned in the background art, achieves bidirectional and non-differential adaptation, completely avoids the risk of reverse connection, has no directional restrictions, lowers the operation threshold, avoids safety accidents, and improves the installation fault tolerance rate; the multi-seal design achieves zero leakage and impact protection, and extends its service life.

[0007] 2. Technical solution.

[0008] This application provides a pneumatically controlled valve, including: a valve seat, a connecting seat, a valve core, a cylinder, a sealing cover, a valve stem, a piston, a locking nut, a fixed seat, and an intake control rotary seat.

[0009] A connecting seat is detachably and fixedly mounted on the valve seat; a cylinder is detachably and fixedly mounted on the connecting seat; and a sealing cover is detachably and fixedly mounted on the upper end of the cylinder.

[0010] The valve seat and the connecting seat are connected by a threaded connection; the connecting seat and the cylinder are connected by a threaded connection; the cylinder and the sealing cover are connected by a threaded connection.

[0011] A valve core is slidably mounted inside the valve seat; a valve stem is fixedly mounted on the valve core; a piston is detachably fixed to the upper end of the valve stem via a lock nut; the piston slides in a sealing manner with the inner wall of the cylinder. A return spring is mounted above the piston. A rubber sealing ring is fixedly mounted on the piston to achieve sealed sliding.

[0012] Connecting pipes are symmetrically fixed on both sides of the valve seat; flanges are fixedly installed on the connecting pipes; the connecting pipes are fixedly connected to the external water pipes through the flanges. The two connecting pipes are at a certain angle; furthermore, the angle between the two connecting pipes is 90 degrees.

[0013] Air pipe A and air pipe B are fixedly installed on the cylinder; a fixed seat is fixedly installed on the cylinder, and an intake control rotary seat is rotatably installed on the fixed seat; The fixed base is connected to air tubes A and B via pipes. The air intake and exhaust of air tubes A and B can be controlled by the air intake control rotary seat.

[0014] The above technical solution involves a connecting pipe that is fixedly connected to an external water pipe via a flange. High-pressure gas is injected into gas pipe A via the air inlet control rotary seat and fixed seat, causing the piston to move upwards. The piston, through the valve stem, moves the valve core upwards, opening the valve. Similarly, high-pressure gas is injected into gas pipe B via the air inlet control rotary seat and fixed seat, causing the piston to move downwards. The piston, through the valve stem, moves the valve core downwards, closing the valve. The two connecting pipes can be connected arbitrarily without directional restrictions, preventing the inlet and outlet pipes of the angle seat valve from being reversed and avoiding accidents. The air inlet control rotary seat is rotatably mounted on the fixed seat, and rotation switches the flow direction of the high-pressure gas source, thereby controlling the opening and closing of the valve.

[0015] As an optional embodiment of this utility model, the valve core, cylinder, sealing cover, valve stem, piston, locking nut, fixed seat, and intake control rotary seat are all made of stainless steel.

[0016] As an optional embodiment of this utility model, the valve seat is provided with a conical groove and an arc-shaped groove; the arc-shaped grooves are smoothly connected to the connecting pipes on both sides and have the same diameter; the conical groove and the arc-shaped groove are connected. The size and shape of the valve core match the conical groove. When the valve core moves to the lowest position, the valve core and the conical groove fit tightly together to achieve a seal and close the valve.

[0017] As an optional embodiment of this invention, an annular groove is formed along the circumference of the conical sealing surface of the valve core. An elastic sealing ring with a circular cross-section is embedded within the annular groove. The outer circumference of the elastic sealing ring is slightly higher than the conical surface of the valve core. When the valve is closed, the elastic sealing ring first contacts the conical groove. As the valve core continues to descend, the sealing ring is compressed, resulting in elastic deformation, filling any possible tiny gaps and achieving an elastic line seal. The deformation of the elastic sealing ring compensates for machining and wear errors, achieving a higher sealing level than a pure hard seal.

[0018] As an optional solution of this utility model, a detachable filter screen is provided at the connection between the arc-shaped groove and the connecting pipe. The filter screen is made of stainless steel, and the mesh size is designed according to the working conditions to intercept particulate impurities.

[0019] As an optional embodiment of this invention, a micro motor is fixedly mounted on the bottom of the mounting base. The intake control rotary base has a cylindrical structure, and the output end of the micro motor is coaxially and fixedly connected to the intake control rotary base. A sealing plate is detachably and fixedly mounted on top of the mounting base, which enables rotational sealing between the mounting base and the intake control rotary base. The micro motor is preferably a stepper motor or a servo motor. The sealing plate ensures that the air passage remains reliably sealed and leak-free even when the rotary base rotates at high speed.

[0020] The mounting base is provided with air hole A and air hole B.

[0021] An intake control rotary table is provided with an intake channel; exhaust channels A and B are symmetrically arranged on both sides of the intake channel. An exhaust pipe and an intake pipe are fixedly installed on the intake control rotary table. Exhaust channels A and B are arranged at a 60-degree angle.

[0022] The exhaust pipe is connected to exhaust passage A and exhaust passage B.

[0023] The intake pipe is connected to the intake channel. An intake valve is fixedly installed on the intake pipe.

[0024] As an optional embodiment of this invention, a permanent magnet is embedded in the upper surface of the intake control rotary seat at a position corresponding to exhaust channel A and exhaust channel B, respectively. Below the sealing plate, a Hall sensor is installed at each of the two extreme rotational positions of the rotary seat. The micro motor is a stepper motor with an encoder or a servo motor.

[0025] As an optional solution of this utility model, an angle sensor is fixedly installed on the intake control rotary seat, and a laser displacement sensor is fixedly installed on the piston.

[0026] An angle sensor is installed on the top or side of the intake control rotary table, and is fixedly mounted coaxially to monitor the rotation angle of the intake control rotary table in real time and continuously.

[0027] A laser displacement sensor is installed at the center of the top of the piston. Correspondingly, a transparent window is opened on the cylinder's sealing cover to allow the laser beam to pass through, directly and non-contactly measuring the absolute displacement of the piston.

[0028] As an optional solution of this utility model, an upper packing, a compensating spring, and a lower packing are sequentially arranged from top to bottom along the valve stem axis inside the valve stem through hole of the connecting seat, and the three together constitute a sandwich-type sealing assembly surrounding the valve stem.

[0029] The upper and lower packings are preferably made of high-performance sealing materials suitable for the working conditions to ensure basic sealing performance; the compensation spring is a corrosion-resistant stainless steel wave spring or a multi-layer cylindrical helical spring, which is initially in a slightly compressed state to apply a continuous and uniform preload to the upper and lower packings.

[0030] As an optional solution of this utility model, the upper packing adopts a composite structure of flexible sealing layer + rigid support layer: the inner layer is a low-friction PTFE soft packing that fits the valve stem to reduce valve stem wear, and the outer layer is a metal-coated graphite hard packing to enhance pressure resistance.

[0031] The lower packing adopts a V-shaped cross-section structure, which uses the medium pressure to self-tighten and seal; the higher the medium pressure, the wider the V-shaped packing opening opens and the stronger the sealing force, forming a medium pressure-assisted seal.

[0032] The compensating spring is a coaxial double-coil wave spring, with the inner and outer coils rotating in opposite directions. This ensures the total preload while preventing unilateral unbalanced loading due to valve stem sway.

[0033] A metal guide ring is installed between the upper and lower packing and the compensation spring to ensure that the spring always runs along the valve stem axis when compressed / rebounded, thus preventing the packing from shifting due to force.

[0034] As an optional solution of this utility model, a packing clamping hole is opened on the top of the connecting seat, and a clamping bolt with external thread is installed in the hole. The lower end of the clamping bolt contacts the top cover of the upper packing. There is no need to disassemble the connecting seat. The clamping force can be supplemented or the old packing can be removed and the new packing can be installed simply by turning the clamping bolt, thus shortening the maintenance time.

[0035] 3. Beneficial effects.

[0036] One or more technical solutions provided in this application have at least the following technical effects or advantages.

[0037] 1. This invention offers convenient installation: bidirectional, seamless compatibility completely eliminates the risk of reverse connection; there are no directional restrictions, lowering the operational threshold; the arc-shaped groove inside the valve seat smoothly connects to the connecting pipes on both sides with the same diameter, the flow channel structure is completely symmetrical, and the two connecting pipes can be arbitrarily connected to external water pipes, with no distinction between inlet and outlet pipes. Compared to traditional angle seat valves that require strict differentiation between inlet and outlet, and whose reverse connection can lead to functional failure or sealing leakage, this application eliminates the need for manual judgment of flow direction, allowing even novices to install quickly, greatly reducing the operational difficulty of on-site construction.

[0038] 2. Avoid safety accidents and improve installation fault tolerance: Traditional angle seat valves may cause problems such as "medium backflow" and "seal failure" when connected in reverse. For example, if the water supply system is connected in reverse, it will cause abnormal pipeline pressure. This application avoids such risks in the fundamental way through the symmetrical flow channel design, and is especially suitable for scenarios with high installation safety requirements such as municipal water supply and industrial circulating water.

[0039] 3. Sealing Reliability: Multiple sealing designs achieve zero leakage and impact protection: The valve core features an elastic line seal, balancing sealing level and buffer protection; the valve core's conical surface is equipped with an annular groove and an elastic sealing ring structure: when closed, the sealing ring first contacts the conical groove, filling machining errors and wear gaps through elastic deformation; at the same time, the sealing ring can absorb the impact force of the valve core moving downwards, completely eliminating water hammer noise caused by hard seals hitting each other, protecting the sealing surfaces of the valve core and valve seat, and extending their service life.

[0040] 4. Dual closing force for enhanced safety in case of gas loss: In the initial closed state, the piston is pushed downward by the combined force of high-pressure air from air pipe B and the return spring. Even if the return spring experiences elasticity decay after long-term use, the high-pressure air can still ensure a tight fit between the valve core and the conical groove, avoiding the leakage problem caused by the aging of traditional single-spring seals. Furthermore, in case of gas loss, the return spring automatically drives the valve to close, meeting the core requirements of industrial safety for gas loss prevention and shut-off.

[0041] 5. Control precision: Automated drive + dual closed-loop positioning, zero error in action: Fully automatic air circuit switching, replacing manual operation; the micro motor at the bottom of the fixed base drives the air intake to control the rotation of the rotating seat, realizing fully automatic air circuit switching between air pipe A and air pipe B, without the need for manual rotation of the rotating seat, which is suitable for the unattended operation requirements of industrial automated production lines. Attached Figure Description

[0042] Figure 1 This is an overall schematic diagram of a pneumatically controlled valve disclosed in a preferred embodiment of this application.

[0043] Figure 2 This is a schematic diagram of the valve seat, connecting seat, valve core, cylinder, valve stem, and piston assembly of a pneumatically controlled valve disclosed in a preferred embodiment of this application.

[0044] Figure 3 This is a schematic diagram of the fit between the fixed seat and the air intake control rotary seat of the pneumatic valve disclosed in a preferred embodiment of this application.

[0045] Figure 4 This is a schematic diagram of the air intake control rotary seat structure of a pneumatic valve disclosed in a preferred embodiment of this application.

[0046] Figure 5 This is a schematic diagram of the internal structure of the air intake control rotary seat of the pneumatic valve disclosed in a preferred embodiment of this application.

[0047] Reference numerals: 1. Valve seat; 2. Connecting seat; 3. Valve core; 4. Cylinder; 5. Sealing cover; 6. Valve stem; 7. Piston; 8. Locking nut; 9. Fixed seat; 10. Intake control rotary seat; 11. Conical groove; 12. Arc groove; 13. Return spring; 14. Connecting pipe; 21. Upper packing; 22. Lower packing; 23. Compensating spring; 41. Air pipe A; 42. Air pipe B; 91. Micro motor; 92. Air port A; 93. Air port B; 101. Exhaust pipe; 102. Intake pipe; 103. Intake passage; 104. Exhaust passage A; 105. Exhaust passage B. Detailed Implementation

[0048] The present application will be further described in detail below with reference to the accompanying drawings.

[0049] Reference Figure 1 and Figure 2 This application provides a pneumatically controlled valve, including: a valve seat 1, a connecting seat 2, a valve core 3, a cylinder 4, a sealing cover 5, a valve stem 6, a piston 7, a locking nut 8, a fixed seat 9, and an air intake control rotary seat 10.

[0050] A connecting seat 2 is detachably fixed on the valve seat 1; a cylinder 4 is detachably fixed on the connecting seat 2; and a sealing cover 5 is detachably fixed on the upper end of the cylinder 4.

[0051] Valve seat 1 and connecting seat 2 are connected by threaded engagement; connecting seat 2 and cylinder 4 are connected by threaded engagement; cylinder 4 and sealing cover 5 are connected by threaded engagement.

[0052] A valve core 3 is slidably mounted inside the valve seat 1; a valve stem 6 is fixedly mounted on the valve core 3; a piston 7 is detachably fixed to the upper end of the valve stem 6 via a locking nut 8; the piston 7 has a sealing sliding fit with the inner wall of the cylinder 4. A return spring 13 is mounted above the piston 7. A rubber sealing ring is fixedly mounted on the piston 7 to achieve sealing sliding. The return spring 13 above the piston 7 ensures that the valve can automatically reset to the closed state in the event of air loss.

[0053] Connecting pipes 14 are symmetrically fixed on both sides of valve seat 1; flanges are fixedly installed on connecting pipes 14; connecting pipes 14 are fixedly connected to external water pipes through flanges. The two connecting pipes 14 are at a certain angle; further, the angle between the two connecting pipes 14 is 90 degrees. A pressure sensor is fixedly installed on the inner wall of the connecting pipe 14.

[0054] The cylinder 4 is fixedly equipped with air pipe A41 and air pipe B42; the cylinder 4 is fixedly equipped with a fixed seat 9, and the fixed seat 9 is rotatably equipped with an air intake control rotary seat 10.

[0055] The fixed base 9 is connected to air pipes A41 and B42 via pipes. The air intake and exhaust of air pipes A41 and B42 can be controlled by the air intake control rotary seat 10.

[0056] In this technical solution, the connecting pipe 14 is fixedly connected to an external water pipe via a flange. High-pressure gas is supplied to the gas pipe A41 via the air intake control rotary seat 10 and the fixed seat 9, causing the piston 7 to move upwards. The piston 7, through the valve stem 6, causes the valve core 3 to move upwards, thus opening the valve. Similarly, high-pressure gas is supplied to the gas pipe B42 via the air intake control rotary seat 10 and the fixed seat 9, causing the piston 7 to move downwards. The piston 7, through the valve stem 6, causes the valve core 3 to move downwards, thus closing the valve. The two connecting pipes 14 can be connected arbitrarily without directional restrictions, preventing the inlet and outlet pipes of the angle seat valve from being reversed and avoiding accidents. The air intake control rotary seat 10 is rotatably mounted on the fixed seat, and rotation switches the flow direction of the high-pressure gas source, thereby controlling the opening and closing of the valve.

[0057] Furthermore, the valve core 3, cylinder 4, sealing cover 5, valve stem 6, piston 7, locking nut 8, fixing seat 9, and intake control rotary seat 10 are all made of stainless steel.

[0058] Reference Figure 2The valve core 3 has a conical structure, and the valve seat 1 has a conical groove 11 and an arc-shaped groove 12. The arc-shaped groove 12 is smoothly connected to the connecting pipes 14 on both sides, and the diameters are the same. The conical groove 11 and the arc-shaped groove 12 are connected. The size and shape of the valve core 3 match the conical groove 11. When the valve core 3 moves to the lowest position, the valve core 3 and the conical groove 11 fit tightly to achieve a seal and close the valve.

[0059] In this technical solution, the two connecting pipes 14 can be connected arbitrarily without directional restrictions, avoiding the reversal of the inlet and outlet pipes of the angle seat valve and preventing accidents. This design ensures that regardless of the direction from which the medium flows in, its flow cross-section and path are the same, thus guaranteeing consistent water flow in the two connecting pipes 14 and achieving flow balance. The valve core 3 adopts a conical structure, and its dimensions and taper perfectly match the conical groove 11. When the valve is closed, the valve core 3, under the action of air pressure and the return spring force, precisely moves to the lowest position, tightly fitting with the conical groove 11 to form a line seal and achieve reliable shut-off. Due to the symmetrical flow channel structure, the direction of medium flow has no impact on valve performance. Therefore, the two connecting pipes 14 can be connected to external water pipes arbitrarily without directional restrictions. This feature fundamentally avoids the functional failure or safety accidents caused by the reversal of the inlet and outlet pipes in traditional angle seat valves, greatly facilitating installation and use.

[0060] Furthermore, an annular groove is formed along the circumference on the conical sealing surface of the valve core 3. A circular elastic sealing ring is embedded within this groove. The outer surface of the elastic sealing ring is slightly higher than the conical surface of the valve core 3. When the valve is closed, the elastic sealing ring first contacts the conical groove 11. As the valve core continues to descend, the sealing ring is compressed, undergoing elastic deformation, filling any possible tiny gaps, thus achieving an elastic line seal. The deformation of the elastic sealing ring compensates for machining and wear errors, achieving a higher sealing level than a pure hard seal. As an elastic buffer, the sealing ring absorbs most of the closing impact force, fundamentally eliminating water hammer noise and protecting the valve core and seat.

[0061] Furthermore, a removable filter screen is installed at the connection between the arc-shaped groove 12 and the connecting pipe 14. The filter screen is made of stainless steel, and the mesh size is designed according to the working conditions to intercept particulate impurities.

[0062] Reference Figure 1 , Figure 3 , Figure 4 and Figure 5A micro motor 91 is fixedly mounted on the bottom of the fixed base 9. The intake control rotary base 10 has a cylindrical structure, and the output end of the micro motor 91 is coaxially and fixedly connected to the intake control rotary base 10. A sealing plate is detachably fixed on top of the fixed base 9, which enables rotational sealing between the fixed base 9 and the intake control rotary base 10. The micro motor 91 is preferably a stepper motor or a servo motor. The sealing plate ensures that the air passage remains reliably sealed and leak-free even when the rotary base rotates at high speed.

[0063] The fixed base 9 is provided with air holes A92 and B93.

[0064] An intake control rotary table 10 is provided with an intake channel 103; an exhaust channel A104 and an exhaust channel B105 are symmetrically arranged on both sides of the intake channel 103. An exhaust pipe 101 and an intake pipe 102 are fixedly installed on the intake control rotary table 10. The exhaust channel A104 and the exhaust channel B105 are arranged at a 60-degree angle.

[0065] The exhaust pipe 101 is connected to the exhaust passage A104 and the exhaust passage B105.

[0066] The intake pipe 102 is connected to the intake channel 103. An intake valve is fixedly installed on the intake pipe 102.

[0067] In this technical solution, initially, the intake channel 103, air port B93, and air pipe B42 are connected. The intake pipe 102 fills the space above the piston 7 with air through the air pipe B42. Combined with the action of the return spring 13, the piston 7 moves to the lowest position, maintaining a good seal and preventing the valve core 3 from becoming loose due to prolonged use of the spring, thus improving the sealing effect. At this time, the space below the piston 7 is connected to the exhaust channel A104 and the exhaust pipe 101, and the space below the piston 7 in the cylinder 4 is not affected by high-pressure gas. When it is necessary to open the valve core 3, the micro motor 91 drives the intake control rotary seat 10 to rotate, so that the intake pipe 102 connects to the air pipe A41 through the air port A92, filling the space below the piston 7 in the cylinder 4 with high-pressure gas. At the same time, the space above the piston 7 connects to the exhaust pipe 101 through the exhaust channel B105, releasing the gas. The high-pressure gas overcomes the elastic force of the return spring 13, causing the piston 7 to move the valve stem 6 and the valve core 3 upward, opening the valve core 3 and opening the valve.

[0068] Furthermore, a permanent magnet is embedded in the upper surface of the intake control rotary seat 10 at a position corresponding to the exhaust channels A104 and B105, respectively. Below the sealing plate, a Hall sensor is installed at each of the two extreme rotational positions of the rotary seat. The micro motor 91 is a stepper motor or servo motor with an encoder.

[0069] In this technical solution, when the intake control rotary table 10 rotates to the closed position, one of the permanent magnets triggers the corresponding Hall sensor, which sends a signal to the control system indicating that the valve is closed. When the rotary table rotates to the open position, another permanent magnet triggers another Hall sensor, sending a signal indicating that the valve is open. By combining the real-time position feedback from the motor encoder and the final positioning signal from the Hall sensor, dual closed-loop control of coarse positioning and fine calibration is achieved. This completely eliminates the cumulative error of the motor, ensuring 100% accurate alignment of the air path every time and reliable valve operation. Even under conditions of vibration or load variation, it maintains extremely high positioning accuracy and system stability.

[0070] Furthermore, an angle sensor is fixedly installed on the intake control rotary table 10, and a laser displacement sensor is fixedly installed on the piston 7.

[0071] An angle sensor is installed on the top or side of the intake control rotary table 10 and is fixedly mounted coaxially to monitor the rotation angle of the intake control rotary table 10 in real time and continuously.

[0072] A laser displacement sensor is mounted at the top center of piston 7. Correspondingly, a transparent window, such as quartz glass or a special transparent plastic, is made on the sealing cover 5 of cylinder 4 to allow the laser beam to pass through. This allows for direct, non-contact measurement of the absolute displacement of piston 7 (i.e., valve core 3).

[0073] Furthermore, within the valve stem through hole of the connecting seat 2, upper packing 21, compensating spring 23, and lower packing 22 are sequentially arranged from top to bottom along the axial direction of the valve stem 6, together forming a sandwich-type sealing assembly surrounding the valve stem 6.

[0074] The upper packing 21 and lower packing 22 are preferably made of high-performance sealing materials suitable for the working conditions (such as polytetrafluoroethylene PTFE for food-grade scenarios, flexible graphite + metal skeleton for high-temperature and high-pressure scenarios, and perfluoroether FFKM for corrosive scenarios) to ensure basic sealing performance; the compensation spring 23 adopts a corrosion-resistant stainless steel wave spring or a multi-layer cylindrical helical spring, which is in a slightly compressed state in the initial state to apply a continuous and uniform preload to the upper and lower packings.

[0075] In this technical solution, the problem of packing wear caused by the reciprocating motion of valve stem 6 is solved by combining packing seal and spring compensation. When the valve stem rubs against the packing for a long time and a small gap appears between the upper and lower packing, the compensation spring 23 will automatically release its elastic potential energy to continuously press the packing, fill the gap, maintain the sealing pressure, and prevent the medium from leaking along the valve stem.

[0076] Furthermore, the upper packing 21 adopts a composite structure of flexible sealing layer + rigid support layer: the inner layer is a low-friction PTFE soft packing that fits the valve stem to reduce valve stem wear, and the outer layer is a metal-coated graphite hard packing to enhance pressure resistance.

[0077] The lower packing 22 adopts a V-shaped cross-section structure (the V-shaped opening faces the medium side) and uses the medium pressure to self-tighten and seal; the higher the medium pressure, the wider the V-shaped packing opening opens and the stronger the sealing force, forming a medium pressure-assisted seal.

[0078] The compensating spring 23 is a coaxial double-coil wave spring. The inner coil spring and the outer coil spring have opposite directions of rotation, which ensures the total preload and avoids unilateral load on the spring due to valve stem sway.

[0079] A metal guide ring is provided between the upper and lower packing and the compensating spring. The gap between the inner hole of the metal guide ring and the valve stem is ≤0.05mm, which ensures that the spring is always along the valve stem axis when compressed / rebounded, and avoids the packing being deviated by force.

[0080] Furthermore, a packing clamping hole is opened at the top of the connecting seat 2, and a clamping bolt with external thread is installed in the hole. The lower end of the clamping bolt contacts the top cover of the upper packing 21. Without disassembling the connecting seat, the clamping force can be supplemented or the old packing can be removed and the new packing installed simply by turning the clamping bolt, thus shortening the maintenance time.

[0081] A transparent observation window made of high-pressure resistant borosilicate glass is opened on the side wall of the connector 2, and the observation window is aligned with the position of the compensation spring 23. At the same time, a red marking line is sprayed on the upper surface of the compensation spring. In the initial state, the marking line is aligned with the upper edge of the observation window. When the packing wears and the spring compression increases, the marking line moves down. If the marking line is lower than the lower edge of the observation window, it indicates that the packing needs to be replaced. A threaded sealing cover is installed on the outside of the observation window. It is closed normally to prevent dust and media contamination, and can be opened for observation during maintenance.

[0082] Furthermore, a PLC control module is fixedly installed on the connecting base 2 to calculate the real-time flow rate based on the height of the piston 7. The PLC control module is a programmable control module, and existing mature products can be used in the market. This is existing technology and will not be elaborated further here. The real-time flow rate calculation model is as follows.

[0083] Q=Cv*π{D 2 / 4-0.25[D0-2*H2tan(θ)] 2}*SQT(2*△P / ρ).

[0084] θ = arctan[D0 / (2H1)]; where: H1 is the height of the valve core cone, H2 is the real-time height of the piston; the real-time vertical displacement of the piston relative to its lowest position (fully closed position). D is the inner diameter of the pipe / arc groove, the maximum possible channel diameter for fluid to pass through the valve. D0 is the bottom diameter of the valve core, the diameter of the thickest part of the valve core cone. It is usually designed to be slightly less than or equal to D to ensure unobstructed flow when the valve is fully open. θ is the valve core half-cone angle, the angle between the valve core centerline and the generatrix of the cone. △P is the pressure difference across the valve, the pressure drop generated between the valve inlet and outlet when fluid flows through the valve, the driving force for fluid flow. ρ is the fluid density. Cv is the flow coefficient, a dimensionless empirical correction coefficient used to correct deviations between theoretical calculations and actual conditions, determined through experiments or CFD simulations; Cv values ​​are between 0.6 and 0.8. Q is the real-time volumetric flow rate, the volume of fluid passing through the valve per unit time. SQT is the square root symbol.

[0085] The working principle of the pneumatically controlled valve of this invention is as follows: Connecting pipe 14 is fixedly connected to an external water pipe via a flange. High-pressure air is injected into air pipe A41 through the air intake control rotary seat 10 and fixed seat 9, causing piston 7 to move upwards. Piston 7, through valve stem 6, causes valve core 3 to move upwards, thus opening the valve. Similarly, high-pressure air is injected into air pipe B42 through the air intake control rotary seat 10 and fixed seat 9, causing piston 7 to move downwards. Piston 7, through valve stem 6, causes valve core 3 to move downwards, thus closing the valve. The two connecting pipes 14 can be connected arbitrarily without directional restrictions, preventing the inlet and outlet pipes of the angle seat valve from being reversed and avoiding accidents.

[0086] This invention completely avoids the risk of reverse connection through bidirectional, non-differentiated adaptation: no directional restrictions lower the operational threshold; the arc-shaped groove inside the valve seat smoothly connects to the connecting pipes on both sides with the same diameter; the flow channel structure is completely symmetrical; the two connecting pipes can be arbitrarily connected to external water pipes, with no distinction between inlet and outlet pipes. This avoids safety accidents and improves installation tolerance. The sealing reliability is ensured through a multi-seal design, achieving zero leakage and impact protection. In the initial closed state, the piston is pushed downwards by the combined force of high-pressure air from air pipe B and a return spring. Even if the return spring experiences elasticity decay after long-term use, the high-pressure air still ensures a tight fit between the valve core and the conical groove, avoiding the leakage problem caused by the aging of traditional single-spring seals.

[0087] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A pneumatically controlled valve, comprising a valve seat, a connecting seat, a valve core, a cylinder, a sealing cover, a valve stem, a piston, a locking nut, a fixed seat, and an air intake control rotary seat; characterized in that: A connecting seat is detachably and fixedly mounted on the valve seat; a cylinder is detachably and fixedly mounted on the connecting seat; a sealing cover is detachably and fixedly mounted on the upper end of the cylinder. A valve core is slidably mounted inside the valve seat; a valve stem is fixedly mounted on the valve core; a piston is detachably fixed to the upper end of the valve stem by a locking nut; the piston slides in a sealing fit with the inner wall of the cylinder; a return spring is mounted above the piston; connecting pipes are symmetrically fixed on both sides of the valve seat; flanges are fixedly mounted on the connecting pipes; the two connecting pipes are set at an included angle. Air pipe A and air pipe B are fixedly installed on the cylinder; a fixed seat is fixedly installed on the cylinder, and an intake control rotary seat is rotatably installed on the fixed seat; the fixed seat is connected to air pipe A and air pipe B through pipes, and the intake and exhaust of air pipe A and air pipe B are controlled by the intake control rotary seat.

2. The gas control valve of claim 1, wherein: The valve seat is provided with a conical groove and an arc-shaped groove; the arc-shaped grooves are smoothly connected to the connecting pipes on both sides and have the same diameter; the conical groove and the arc-shaped groove are connected, and the size and shape of the valve core match the conical groove. When the valve core moves to the lowest position, the valve core and the conical groove fit tightly to achieve a seal and close the valve.

3. The gas control valve of claim 1, wherein: A micro motor is fixedly installed at the bottom of the fixed base; the intake control rotary seat has a cylindrical structure, and the output end of the micro motor is coaxially fixedly connected to the intake control rotary seat; a sealing plate is detachably fixedly installed on the top of the fixed base; air holes A and B are provided on the fixed base; an intake channel is provided on the intake control rotary seat; exhaust channels A and B are symmetrically arranged on both sides of the intake channel; an exhaust pipe and an intake pipe are fixedly installed on the intake control rotary seat; the exhaust pipe is connected to exhaust channels A and B, and the intake pipe is connected to the intake channel.

4. The gas control valve of claim 3, wherein: Exhaust passage A and exhaust passage B are set at a 60-degree angle, and an intake valve is fixedly installed on the intake pipe.

5. The gas control valve of claim 2, wherein: A removable filter screen made of stainless steel is installed at the connection between the arc-shaped groove and the connecting pipe.

6. The gas control valve of claim 1, wherein: An angle sensor is fixedly installed on the intake control rotary table, and a laser displacement sensor is fixedly installed on the piston.

7. The gas control valve of claim 1, wherein: The valve core, cylinder, sealing cover, valve stem, piston, lock nut, mounting base, and intake control rotary seat are all made of stainless steel.

8. The gas control valve of claim 2, wherein: Inside the valve stem through hole of the connecting seat, the upper packing, the compensating spring and the lower packing are arranged sequentially from top to bottom along the valve stem axis. The upper packing adopts a composite structure of a flexible sealing layer and a rigid support layer: the inner layer is a low-friction PTFE soft packing that fits the valve stem, and the outer layer is a metal-coated graphite hard packing. The lower packing adopts a V-shaped cross-section structure and uses the medium pressure to self-tighten and seal; The compensating spring is a coaxial double-coil wave spring, with the inner and outer coils rotating in opposite directions. A metal guide ring is provided between the upper and lower packings and the compensation spring.

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