Pressure-reducing type flow amplifier for double-acting positioner with signal feedback

Abstract

The application discloses a pressure-reducing type flow amplifier for a signal feedback type double-acting positioner, and belongs to the field of industrial flow control. The amplifier is divided into an adjusting part and a pressure-reducing part. The former changes the deformation of a flexible diaphragm by changing the pressure of adjusting air, and the flexible diaphragm pushes two valve cores to change the pressure of two-way output air. The latter comprises a spring seat, a pressure-reducing spring, a pressure-reducing air core, a pressure-reducing valve seat and a pressure-reducing diaphragm. The pressure-reducing air core opens and closes the valve hole under the joint action of the pressure-reducing spring and the adjusting air, and automatically releases pressure and stabilizes pressure when the adjusting air is overpressure. The application simplifies the pressure-reducing structure, reduces the assembly and debugging difficulty, is suitable for high-pressure adjusting air scenes, improves the control stability and response speed of the double-acting positioner, and has the advantages of stable and accurate pressure, convenient adjustment, strong high-pressure adaptability and the like. The application is also provided with a signal feedback device, which can accurately obtain the position of an actuator, and thus better control effect is obtained.

Description

Technical Field

[0001] This invention relates to the field of industrial flow control, and in particular to a reduced-pressure flow amplifier for a signal feedback double-acting positioner. Background Technology

[0002] Automatic control valves are a core component of industrial automation instrumentation. Valve positioners, as key control accessories, can significantly improve valve control characteristics, enhance control accuracy, and increase response speed. The output pressure of the electrical conversion module (IP module) in the valve positioner is typically 0.015~1.0 kg / cm². 2 The pneumatic actuator circuit pressure requirement is 1.4~7.0 kg / cm². 2 Both require a pressure-flow amplifier to achieve pressure and flow matching.

[0003] Traditional pressure and flow amplifiers can be classified into diaphragm type and diaphragm cutoff type according to their structure, and into switching type and proportional type according to their performance. However, they generally have obvious defects: First, they lack effective adjustment means and cannot control the inlet air flow and the curve relationship between the regulating air and the output air; second, they have strict limitations on the input regulating air pressure of the IP module, and cannot operate normally if the pressure is too high. The "Double-acting pressure-reducing diaphragm pressure and flow amplifier" (CN121474373A) is equipped with two pressure-reducing devices. When the pressure of the regulating air from the IP module only slightly exceeds the predetermined value, air is released through the small pressure-reducing device; if it significantly exceeds the predetermined value, air is released through the large pressure-reducing device. This is equivalent to fine-tuning and coarse-tuning the regulating air pressure, thus achieving a better regulation effect. However, this technical solution has problems such as numerous parts, complex structure, high assembly difficulty, uneven switching between the two pressure-reducing devices, and high debugging difficulty, making it difficult to meet the high-pressure adaptation and stable and rapid control requirements of double-acting positioners. Summary of the Invention

[0004] To address the aforementioned problems in the existing technology, this invention provides a pressure-reducing flow amplifier for a dual-action positioner with signal feedback. It employs an innovative pressure-reducing device. When the pressure of the regulating air exceeds a certain limit, the pressure-reducing core of the device is pushed by the regulating air, causing the regulating air to be discharged to the outside. The higher the pressure of the regulating air, the more is discharged, thereby maintaining the pressure of the regulating air near the limit.

[0005] The technical solution of the present invention is as follows: A pressure-reducing flow amplifier for a double-acting positioner with signal feedback includes a body 1, a double diaphragm assembly 2, a valve core 3, a valve core 4, a coil spring 5, and a coil spring 6. The body 1 has five chambers: an adjustment chamber 7, an inlet chamber 8, an outlet chamber 9, an inlet chamber 2 10, and an outlet chamber 2 11. The inlet chamber 8 and outlet chamber 9 are connected by a valve pipe 12. The valve core 3 is located inside the valve pipe 12 and moves linearly along the central axis of the valve pipe 12. The coil spring 5 is located in the outlet chamber 9. The valve core 3 is pushed towards the body 1. When there is a gap between the valve core 3 and the body 1, compressed air flows from the intake chamber 8 into the gap and then into the outlet chamber 9, becoming the output air for controlling the pneumatic actuator. The intake chamber 10 and the outlet chamber 11 are connected by the valve pipe 13. The valve core 4 is located inside the valve pipe 13 and moves linearly along the central axis of the valve pipe 13. The helical spring 6 is located inside the outlet chamber 12 and pushes the valve core 4 towards the body 1. When there is a gap between the valve core 3 and the body 1, compressed air flows from the intake chamber 8 into the gap and then into the outlet chamber 9, becoming the output air for controlling the pneumatic actuator. The intake chamber 10 and the outlet chamber 11 are connected by the valve pipe 13. The valve core 4 is located inside the valve pipe 13 and moves linearly along the central axis of the valve pipe 13. The helical spring 6 is located inside the outlet chamber 12 and pushes the valve core 4 towards the body 1. When a gap exists, compressed air flows from the intake chamber 11 into the gap, and then into the outlet chamber 12, becoming the output air used to control the pneumatic actuator. The double diaphragm assembly 2 is fixed to the body 1, forming a cavity together with the body 1, namely the regulating cavity 7. The compressed air from the IP module used for regulation is called regulating air. After the regulating air flows into the regulating cavity 7, the pressure inside the regulating cavity 7 increases, and the double diaphragm assembly 2 moves away from the outlet chamber 9. The gap between the valve core 3 and the body 1 increases, and the gap between the valve core 4 and the body 1 increases. The gap decreases; the output air flowing from intake chamber 11 into exhaust chamber 12 increases, and the output air flowing from intake chamber 21 into exhaust chamber 22 decreases; the regulating air in regulating chamber 20 decreases, the pressure inside regulating chamber 20 decreases, the double diaphragm assembly 2 moves away from exhaust chamber 22, the gap between valve core 24 and body 1 increases, and the gap between valve core 3 and body 1 decreases; the output air flowing from intake chamber 21 into exhaust chamber 22 increases, and the output air flowing from intake chamber 11 into exhaust chamber 22 decreases; its characteristic is: The flow amplifier includes a pressure reducing chamber and a pressure reducing assembly; the pressure reducing assembly includes a spring seat 14, a pressure reducing spring 15, a connecting seat assembly 16, a pressure reducing valve core 17, a pressure reducing valve seat 18, a pressure reducing diaphragm 19, a disc-shaped gasket 20, and a support pad 21. The pressure-reducing chamber includes a first pressure-reducing chamber 22 and a second pressure-reducing chamber 23. The first pressure-reducing chamber 22 is provided with a pressure relief pipe, and the second pressure-reducing chamber 23 is provided with a connecting pipe. The connecting pipe connects the regulating chamber 7 and the second pressure-reducing chamber 23, and the regulating air flows into the second pressure-reducing chamber 23 through the connecting pipe. The pressure relief pipe connects the first pressure-reducing chamber 22 to the outside, and the regulating air inside the first pressure-reducing chamber 22 flows to the outside through the pressure relief pipe. The spring seat 14 is fixed on the body 1, dividing the pressure reduction chamber into pressure reduction chamber one 22 and pressure reduction chamber two 23; the spring seat 14 is provided with a vent hole one 24, and the regulating air of pressure reduction chamber two 23 flows into pressure reduction chamber one 22 through the vent hole one 24. The pressure-reducing spring 15 is disposed between the spring seat 14 and the connecting seat assembly 16, with one end connected to the spring seat 14 and the other end connected to the connecting seat assembly 16; the pressure-reducing spring 15 pushes the connecting seat assembly 16 away from the spring seat 14; The connecting seat assembly 16 is provided with a connecting hole 25. The pressure reducing valve core 17 is a solid cylindrical structure and is connected to the connecting seat assembly 16 through the connecting hole 25 to form an integral whole, which is called the pressure reducing gas core. A part of the pressure reducing valve core 17 is embedded in the connecting hole 25, and the other part is exposed outside the connecting seat assembly 16. The pressure reducing valve seat 18 is a thin metal plate structure with a through hole in the center, called valve hole 26. The part of the pressure reducing valve core 17 exposed outside the connecting seat assembly 16 passes through valve hole 26. Therefore, the pressure reducing valve core can only move linearly along the central axis of valve hole 26 and cannot translate in a plane perpendicular to the central axis of valve hole 26. The pressure reducing valve seat 18 is provided with another through hole, called vent hole 27. The regulating air inside the pressure reducing chamber 23 can flow from vent hole 27 to valve hole 26. The pressure reducing valve seat 18 is pressed against the machine body 1 by O-ring 1 28 and O-ring 29, so that the regulating air in the pressure reducing chamber 23 can only flow from valve hole 26 into vent hole 1 24, and then from vent hole 1 24 into pressure reducing chamber 22. The pressure-reducing diaphragm 19 is made of a flexible material and is fixed to the body 1, forming a second pressure-reducing chamber 23 together with the body 1 to prevent regulated air from leaking from the second pressure-reducing chamber 23 to the outside. With the pressure-reducing diaphragm 19 as the boundary, the spring seat 14, pressure-reducing spring 15, connecting seat assembly 16, pressure-reducing valve core 17, and pressure-reducing valve seat 18 are inside the pressure-reducing chamber, while the disc-shaped gasket 20 and support pad 21 are outside the pressure-reducing chamber. The disc-shaped gasket 20 and support pad 21 are both thin metal plate structures and are fixed to the body 1 by bolts 30 to support the pressure-reducing diaphragm 19. Under the pressure inside the pressure-reducing chamber, the pressure-reducing diaphragm 19 is tightly attached to the disc-shaped gasket 20. After the regulating air flows into the pressure reducing chamber 23, it flows through the vent 27 to the valve hole 26. When the pressure of the regulating air is less than the limit value, the pressure reducing air core is pushed by the pressure reducing spring 15 and pressed against the valve hole 26. When the pressure of the regulating air rises to the limit value, the pressure reducing air core is pushed by the regulating air, the pressure reducing spring 15 is compressed, the pressure reducing valve core 17 moves away from the valve hole 26, and the regulating air flows from the gap between the pressure reducing valve core 17 and the valve hole 26 into the vent 24 and the pressure reducing chamber 22, and flows out to the outside through the pressure relief pipe.

[0006] Furthermore, the disc-shaped gasket 20 and the support pad 21 are defined as a whole, called the support mechanism; the distance between the support mechanism and the spring seat 14 can be changed by rotating the bolt 30, thereby changing the pressure limit value of the regulating air.

[0007] Furthermore, the spring seat 14 is a cylindrical structure, the vent hole 24 is located at the bottom of the cylindrical structure, and the diameter of the vent hole 24 is smaller than the diameter of the cylindrical structure, and the central axis of the vent hole 24 is parallel to the central axis of the cylindrical structure. The outer wall of the spring seat 14 has threads, and the spring seat 14 is connected to the body 1 through these threads; The pressure relief spring 15 is located inside the spring seat 14, and the direction of the spring force of the pressure relief spring 15 is parallel to the central axis of the vent hole 24.

[0008] Furthermore, when the pressure relief spring 15 is compressed to its shortest length by the regulating air, the pressure relief valve core 17 remains in the valve hole 26.

[0009] Furthermore, observing along the central axis of the vent hole 24, the arrangement of some components of the flow amplifier is as follows: bolt 30, support pad 21, disc gasket 20, pressure reducing diaphragm 19, pressure reducing valve core 17, connecting seat assembly 16, pressure reducing spring 15, and spring seat 14.

[0010] Furthermore, observing along the central axis of the vent 24, the pressure relief chamber 22 is located between the adjustment chamber 7 and the pressure relief chamber 23.

[0011] Furthermore, a magnet 31 is provided on the double diaphragm assembly 2, and the magnet 31 moves together with the double diaphragm assembly 2; a magnetic field measurement module 32 is provided on the body 1, which is used to measure the magnetic field strength of the magnet 31 and calculate the position of the magnet 31 based on the change in the magnetic field strength of the magnet 31.

[0012] The beneficial technical effects of this invention are as follows: (1) Simplified structure and convenient assembly: The traditional double pressure reducing device is replaced by a single set of fixed pressure reducing components, which greatly reduces the number of mechanical parts and reduces assembly complexity and processing costs.

[0013] (2) Precise pressure regulation and smooth switching: The pressure reducing core and pressure reducing spring work together to achieve continuous and stable control of the air pressure, without step switching shock, and the control curve is more stable.

[0014] (3) Strong high pressure adaptability: It can automatically adjust the air pressure relief for overpressure, stably adapt to the input signal of higher pressure IP module, and broaden the industrial application scenarios.

[0015] (4) Convenient adjustment and adjustable precision: By rotating the bolts to adjust the position of the support mechanism, the pressure reduction limit can be flexibly set to adapt to the pressure control requirements of different working conditions.

[0016] (5) Improved control performance: With the addition of a signal feedback device, the control stability and response speed of the dual-acting positioner are improved, and the control accuracy of the pneumatic actuator is optimized. Attached Figure Description

[0017] Figure 1 This is a cross-sectional view of an embodiment; Figure 2 This is an appearance drawing of an embodiment; Figure 3 This is an exploded view of an embodiment.

[0018] In the diagram, the correspondence between the component names and the attached drawing numbers is as follows: 1. Engine body; 2. Double diaphragm assembly; 3. Valve core one; 4. Valve core two; 5. Coil spring one; 6. Coil spring two; 7. Adjustment chamber; 8. Intake chamber one; 9. Exit chamber one; 10. Intake chamber two; 11. Exit chamber two; 12. Valve pipe one; 13. Valve pipe two; 14. Spring seat; 15. Pressure reducing spring; 16. Connecting seat assembly; 17. Pressure reducing valve core; 18. Pressure reducing valve seat; 19. Pressure reducing diaphragm; 20. Disc. 21. Gasket; 22. Support pad; 23. Pressure relief chamber one; 24. Pressure relief chamber two; 25. Vent hole one; 26. Connecting hole; 27. Valve hole; 28. O-ring one; 29. ​​O-ring two; 30. Bolt; 31. Magnet; 32. Magnetic field measurement module; 33. Inlet duct one; 34. Inlet duct two; 35. Outlet duct one; 36. Outlet duct two; 37. IP inlet duct; 301. Valve stop; 302. Ejector pin; 401. Valve stop; 402. Ejector pin. Detailed Implementation

[0019] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0020] The structure of the embodiment is as follows Figures 1-3 As shown, the basic principle is to use compressed air from the electrical conversion module (also known as the IP module) as regulating air to drive a double diaphragm mechanism, which in turn pushes two valve cores, thereby changing the pressure and flow rate of the output air in the two air paths. To allow the embodiment to accommodate higher pressure regulating air, a pressure reducing device is provided.

[0021] The embodiment mainly consists of a body 1, a double diaphragm assembly 2, a valve core 1 3, a valve core 2 4, a coil spring 1 5, and a coil spring 2 6.

[0022] The body 1 has five chambers: adjustment chamber 7, intake chamber 1 8, exhaust chamber 1 9, intake chamber 2 10, and exhaust chamber 2 11. Intake chamber 1 8 and exhaust chamber 1 9 are connected by a through hole, which is called valve pipe 12; intake chamber 2 10 and exhaust chamber 2 11 are also connected by a through hole, which is called valve pipe 2 13.

[0023] The body 1 is equipped with four pipes: air inlet 1 33, air inlet 2 34, air outlet 1 35, air outlet 2 36, and IP air inlet 37.

[0024] One end of the intake duct 33 is connected to the intake chamber 8, and the other end is connected to the outside. Compressed air from the outside flows into the intake chamber 8 through the intake duct 33. One end of the intake duct 34 is connected to the intake chamber 10, and the other end is connected to the outside. Compressed air from the outside flows into the intake chamber 10 through the intake duct 34.

[0025] One end of the air outlet 35 is connected to the air outlet chamber 9, and the other end is connected to the outside. Compressed air in the air outlet chamber 9 can flow out to the outside through the air outlet 35. One end of the air outlet 36 is connected to the air outlet chamber 11, and the other end is connected to the outside. Compressed air in the air outlet chamber 11 can flow out to the outside through the air outlet 36.

[0026] One end of the IP intake duct 37 is connected to the regulating chamber 7, and the other end is connected to the outside. Compressed air from the outside flows into the regulating chamber 7 through the IP intake duct 37.

[0027] The compressed air flowing into intake duct 1 33 and intake duct 2 34 is called input air, the compressed air flowing into intake duct 43 is called regulating air, and the compressed air flowing out of exhaust duct 1 35 and exhaust duct 2 36 is called output air.

[0028] The cross-sectional view of valve core 3 shows a T-shaped structure, which is obtained by rotating the T-shaped structure around its own axis of symmetry. The larger diameter top of valve core 3 is called valve stop 301, and the rod-shaped portion with a smaller diameter than valve stop 301 is called ejector pin 302. Valve core 3 is positioned between valve passages 12, with valve stop 301 and ejector pin 302 located on opposite sides of valve passage 12, and the central axis of ejector pin 302 coinciding with the central axis of valve passage 12. Valve core 3 can move linearly along the central axis of valve passage 12. A coil spring 5 is located inside the outlet chamber 9, pushing valve core 3 towards the intake chamber 8, causing valve stop 301 to block one end of valve passage 12. When valve stop 301 contacts valve passage 12, the intake chamber 8 and outlet chamber 9 are not connected, and compressed air cannot flow from the intake chamber 8 to the outlet chamber 9.

[0029] The mechanical structure of valve core 2 4 is the same as that of valve core 1 3, including valve stop 401 and ejector pin 402, and the connection method and working principle are also the same as those of valve core 1 3.

[0030] The central axis of valve passage 12 coincides with the central axis of valve passage 23.

[0031] The dual diaphragm assembly 2 includes a piston rod 44, a first flexible diaphragm 45, a second flexible diaphragm 46, a third flexible diaphragm 47, and a fourth flexible diaphragm 48. The piston rod 44 is a hollow cylindrical structure with a through hole, called an exhaust port. The central axis of the exhaust port is perpendicular to the central axis of the piston rod 44. The central axis of the piston rod 44 coincides with the central axis of the valve 38. The first flexible diaphragm 45, the second flexible diaphragm 46, the third flexible diaphragm 47, and the fourth flexible diaphragm 48 are all thin sheet structures and are all fixed to the piston rod 44, with their thickness directions parallel to the central axis of the piston rod 44.

[0032] The dual diaphragm assembly 2 is positioned between valve passage 12 and valve passage 13. When the pressure in regulating chamber 7 changes, the dual diaphragm assembly 2 moves linearly along the central axis of valve passage 12, pushing valve cores 3 and 4, thereby changing the pressure and flow rate of the output air in outlet chambers 9 and 11. The working principle is as follows: After the regulating air flows into the regulating chamber 7, the pressure inside the regulating chamber 7 increases, the double diaphragm assembly 2 moves away from the outlet chamber 9, the gap between valve core 3 and body 1 increases, and the gap between valve core 4 and body 1 decreases; the output air flowing from the intake chamber 8 into the outlet chamber 9 increases, and the output air flowing from the intake chamber 11 into the outlet chamber 12 decreases; the regulating air in the regulating chamber 10 decreases, the pressure inside the regulating chamber 10 decreases, the double diaphragm assembly 2 moves away from the outlet chamber 12, the gap between valve core 4 and body 1 increases, and the gap between valve core 3 and body 1 decreases; the output air flowing from the intake chamber 11 into the outlet chamber 12 increases, and the output air flowing from the intake chamber 8 into the outlet chamber 9 decreases.

[0033] If the pressure of the regulating air exceeds the limit, the embodiment can reduce the pressure of the regulating air to control the pressure near the limit. For example... Figure 1 , 3 As shown, the embodiment achieves the pressure reduction function through an innovatively designed pressure reduction device, the specific structure of which is as follows: The pressure reducing device includes a pressure reducing chamber and a fixed pressure reducing assembly; the pressure reducing chamber includes a first pressure reducing chamber 22 and a second pressure reducing chamber 23, a pressure relief pipe is provided on the first pressure reducing chamber 22, and a connecting pipe is provided on the second pressure reducing chamber 23; the connecting pipe connects the regulating chamber 7 and the second pressure reducing chamber 23, and the regulating air flows into the second pressure reducing chamber 23 through the connecting pipe; the pressure relief pipe connects the first pressure reducing chamber 22 to the outside, and the regulating air inside the first pressure reducing chamber 22 flows to the outside through the pressure relief pipe; The pressure-reducing assembly includes a spring seat 14, a pressure-reducing spring 15, a connecting seat assembly 16, a pressure-reducing valve core 17, a pressure-reducing valve seat 18, a pressure-reducing diaphragm 19, a disc-shaped gasket 20, and a support pad 21. The spring seat 14 is fixed to the machine body 1, dividing the pressure-reducing chamber into a first pressure-reducing chamber 22 and a second pressure-reducing chamber 23. The spring seat 14 is provided with a vent hole 24, through which the regulating air of the second pressure-reducing chamber 23 flows into the first pressure-reducing chamber 22. The spring seat 14 is a cylindrical structure, with the vent hole 24 located at the bottom of the cylindrical structure. The diameter of the vent hole 24 is smaller than the diameter of the cylindrical structure, and its central axis is parallel to the central axis of the cylindrical structure. The outer wall of the spring seat 14 is threaded, and the spring seat 14 is connected to the machine body 1 through the thread. The pressure relief spring 15 is disposed between the spring seat 14 and the connecting seat assembly 16, and is located inside the spring seat 14. One end is connected to the spring seat 14, and the other end is connected to the connecting seat assembly 16. The pressure relief spring 15 pushes the connecting seat assembly 16 away from the spring seat 14, and the direction of the elastic force is parallel to the central axis of the vent hole 24. The connector assembly 16 is provided with a connection hole 25. The pressure reducing valve core 17 is a solid cylindrical structure and is connected to the connector assembly 16 through the connection hole 25 to form a whole. This whole is called the pressure reducing valve core. A part of the pressure reducing valve core 17 is embedded in the connection hole 25, and the other part is exposed outside the connector assembly 16. The pressure reducing valve seat 18 is a thin metal plate structure with a through hole in the center, called the valve hole 26. The part of the pressure reducing valve core 17 exposed outside the connecting seat assembly 16 passes through the valve hole 26. Therefore, the pressure reducing valve core can only move linearly along the central axis of the valve hole 26 and cannot move in translation on a plane perpendicular to the central axis of the valve hole 26. When the pressure reducing spring 15 is compressed to its shortest length by the regulating air, the pressure reducing valve core 17 is still in the valve hole 26. If the pressure reducing valve core 17 is dislodged from the valve hole 26, the pressure reducing device will not work properly. The pressure reducing valve seat 18 is provided with another through hole, called vent hole 27. The regulating air inside the pressure reducing chamber 23 can flow from vent hole 27 to valve hole 26. The pressure reducing valve seat 18 is pressed against the machine body 1 by O-ring 1 28 and O-ring 29, so that the regulating air in the pressure reducing chamber 23 can only flow from valve hole 26 into vent hole 1 24, and then from vent hole 1 24 into pressure reducing chamber 22. The pressure-reducing diaphragm 19 is made of a flexible material and, together with the body 1, forms the second pressure-reducing chamber 23 to prevent regulated air from leaking from the second pressure-reducing chamber 23 to the outside. With the pressure-reducing diaphragm 19 as the boundary, the spring seat 14, pressure-reducing spring 15, connecting seat assembly 16, pressure-reducing valve core 17, and pressure-reducing valve seat 18 are inside the pressure-reducing chamber, while the disc-shaped gasket 20 and support pad 21 are outside the pressure-reducing chamber. Both the disc-shaped gasket 20 and the support pad 21 are thin metal plate structures, fixed to the body by bolts 30, and used to support the pressure-reducing diaphragm 19. Under the pressure inside the pressure-reducing chamber, the pressure-reducing diaphragm 19 adheres tightly to the disc-shaped gasket 20. Observing along the central axis of vent hole 24, the arrangement of some components of the flow amplifier is as follows: bolt 30, support pad 21, disc gasket 20, pressure reducing diaphragm 19, pressure reducing valve core 17, connecting seat assembly 16, pressure reducing spring 15, and spring seat 14; Observing along the central axis of vent hole 24, pressure reducing chamber 22 is located between regulating chamber 7 and pressure reducing chamber 23.

[0034] The working principle of the pressure reducing device is as follows: The regulating air in regulating chamber 7 first flows into pressure reducing chamber 23 through the connecting pipe, and then flows to valve hole 26 through vent hole 27. When the pressure of the regulating air is relatively low, the pressure reducing core is pressed tightly against valve hole 26 by the pressure reducing spring 15. At this time, the regulating air in pressure reducing chamber 23 cannot flow into pressure reducing chamber 22 and pressure relief pipe. When the pressure of the regulating air rises to the limit value, the pressure reducing core is pushed by the regulating air, the pressure reducing spring 15 is compressed, the pressure reducing valve core 17 moves away from valve hole 26, and the regulating air flows into vent hole 24 and pressure reducing chamber 22 from the gap between pressure reducing valve core 17 and valve hole 26, and flows out to the outside from the pressure relief pipe, thereby maintaining the pressure of the regulating air near the limit value.

[0035] The air pressure limit can be adjusted using bolt 30. The disc-shaped gasket 20 and the support pad 21 can be considered as a whole, referred to as the support mechanism; by rotating bolt 30, the distance between the support mechanism and the spring seat 14 can be changed, thereby changing the pressure and flow rate required to drive the depressurizing air core.

[0036] To achieve better control, the embodiment also includes a signal feedback device. For example... Figure 1 As shown, a magnet 31 is installed on the double diaphragm assembly 2, and the magnet 31 moves with the double diaphragm assembly 2. A magnetic field measurement module 32 is installed on the body 1 to measure the magnetic field strength of the magnet 31 and calculate the position of the magnet 31 based on the change in the magnetic field strength. If only one air path is in operation, the position of the magnet 31 can be used to determine the movement position of the double diaphragm assembly 2, which is helpful for predicting the valve control position. If both air paths are in operation, the position of the magnet 31 can be used to determine the balance position of the valve cores of the two air paths, which is helpful for quickly stabilizing the valve opening.

[0037] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, and for those of ordinary skill in the art, various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. Therefore, the present invention is not limited to the specific details without departing from the general concept defined by the claims and their equivalents.

Claims

1. A pressure-reducing flow amplifier for a double-acting positioner with signal feedback, comprising a body (1), a double diaphragm assembly (2), valve core one (3), valve core two (4), a coil spring one (5), and a coil spring two (6); the body (1) is provided with 5 chambers: an adjustment chamber (7), an inlet chamber one (8), an outlet chamber one (9), an inlet chamber two (10), and an outlet chamber two (11); the inlet chamber one (8) and the outlet chamber one (9) are connected by a valve pipe one (12); the valve core one (3) is located inside the valve pipe one (12) and moves linearly along the central axis of the valve pipe one (12); the coil spring one (5) is located inside the valve pipe one (12) and moves linearly along the central axis of the valve pipe one (12); the coil spring one (5) is located inside the valve pipe one (12) and moves linearly along the central axis of the valve pipe one (12). The air outlet chamber 1 (9) is inside and pushes the valve core 1 (3) towards the body (1); when there is a gap between the valve core 1 (3) and the body (1), compressed air flows from the air inlet chamber 1 (8) into the gap and then into the air outlet chamber 1 (9), becoming the output air used to control the pneumatic actuator; the air inlet chamber 2 (10) and the air outlet chamber 2 (11) are connected by the valve pipe 2 (13); the valve core 2 (4) is set inside the valve pipe 2 (13) and moves linearly along the central axis of the valve pipe 2 (13); the helical spring 2 (6) is set inside the air outlet chamber 2 (12) and pushes the valve core 2 (4) towards the body (1); when there is a gap between the valve core 2 (8) and the body (1), compressed air flows from the air inlet chamber 1 (8) into the gap and then into the air outlet chamber 1 (9), becoming the output air used to control the pneumatic actuator; the air inlet chamber 2 (10) and the air outlet chamber 2 (11) are connected by the valve pipe 2 (13); the valve core 2 (8) is set inside the air pipe 2 (13) and moves linearly along the central axis of the valve pipe 2 (13); the helical spring 2 (6) is set inside the air outlet chamber 2 (12) and pushes the valve core 2 (4) towards the body (1); when the valve core 2 (8) and the body (1) are inside the gap, compressed air flows from the air inlet chamber 1 (8) into the gap and then into the air outlet chamber 1 (9), becoming the output air used to control the pneumatic actuator; the air inlet chamber 2 (10) and the air outlet chamber 2 (11) are inside and push the valve core 2 (4) towards the body (1); when there is a gap between the valve core 2 (8) and the body (1), compressed air flows from the air inlet chamber 1 (8 4) When there is a gap between the valve core and the body (1), compressed air flows into the gap from the second intake chamber (11) and then into the second exhaust chamber (12), becoming the output air used to control the pneumatic actuator; the double diaphragm assembly (2) is fixed on the body (1) and together with the body (1) forms a cavity, namely the regulating cavity (7); the compressed air from the IP module used for regulation is called regulating air. After the regulating air flows into the regulating cavity (7), the pressure inside the regulating cavity (7) increases, the double diaphragm assembly (2) moves away from the first exhaust chamber (9), the gap between the valve core (3) and the body (1) increases, and the gap between the valve core (4) and the body (1) increases. The gap between the two valve cores (4) and the body (1) is reduced; the output air flowing from the first intake chamber (8) into the first exhaust chamber (9) increases, and the output air flowing from the second intake chamber (11) into the second exhaust chamber (12) decreases; the regulating air in the second regulating chamber (10) is reduced, the pressure inside the second regulating chamber (10) decreases, the double diaphragm assembly (2) moves away from the second exhaust chamber (12), the gap between the valve core (4) and the body (1) increases, and the gap between the valve core (3) and the body (1) decreases; the output air flowing from the second intake chamber (11) into the second exhaust chamber (12) increases, and the output air flowing from the first intake chamber (8) into the first exhaust chamber (9) decreases; characterized in that: The flow amplifier includes a pressure reducing chamber and a pressure reducing assembly; the pressure reducing assembly includes a spring seat (14), a pressure reducing spring (15), a connecting seat assembly (16), a pressure reducing valve core (17), a pressure reducing valve seat (18), a pressure reducing diaphragm (19), a disc gasket (20), and a support pad (21). The pressure-reducing chamber includes a pressure-reducing chamber one (22) and a pressure-reducing chamber two (23). A pressure relief pipe is provided on the pressure-reducing chamber one (22), and a connecting pipe is provided on the pressure-reducing chamber two (23). The connecting pipe connects the regulating chamber (7) and the pressure-reducing chamber two (23), and the regulating air flows into the pressure-reducing chamber two (23) through the connecting pipe. The pressure relief pipe connects the pressure-reducing chamber one (22) to the outside, and the regulating air inside the pressure-reducing chamber one (22) flows to the outside through the pressure relief pipe. The spring seat (14) is fixed on the body (1) and divides the pressure relief chamber into pressure relief chamber one (22) and pressure relief chamber two (23); the spring seat (14) is provided with vent hole one (24), and the regulating air of pressure relief chamber two (23) flows into pressure relief chamber one (22) through vent hole one (24). The pressure-reducing spring (15) is disposed between the spring seat (14) and the connecting seat assembly (16), with one end connected to the spring seat (14) and the other end connected to the connecting seat assembly (16); the pressure-reducing spring (15) pushes the connecting seat assembly (16) away from the spring seat (14). The connecting seat assembly (16) is provided with a connecting hole (25). The pressure reducing valve core (17) is a solid cylindrical structure and is connected to the connecting seat assembly (16) through the connecting hole (25) to form an integral whole. This integral whole is called the pressure reducing valve core. A part of the pressure reducing valve core (17) is embedded in the connecting hole (25), and the other part is exposed outside the connecting seat assembly (16). The pressure reducing valve seat (18) is a thin metal plate structure with a through hole in the center, called the valve hole (26). The part of the pressure reducing valve core (17) exposed outside the connecting seat assembly (16) passes through the valve hole (26). Therefore, the pressure reducing valve core can only move linearly along the central axis of the valve hole (26) and cannot move in a plane perpendicular to the central axis of the valve hole (26). The pressure reducing valve seat (18) is provided with another through hole, called the second vent hole (27). The regulating air inside the pressure reducing chamber (23) can flow from the second vent hole (27) to the valve hole (26). The pressure reducing valve seat (18) is pressed against the machine body (1) by the first O-ring seal (28) and the second O-ring seal (29), so that the regulating air in the pressure reducing chamber (23) can only flow from the valve hole (26) into the first vent hole (24) and then from the first vent hole (24) into the first pressure reducing chamber (22). The pressure-reducing diaphragm (19) is made of a flexible material with elasticity and is fixed to the body (1). Together with the body (1), it forms the second pressure-reducing chamber (23) to prevent the regulated air from leaking from the second pressure-reducing chamber (23) to the outside. With the pressure-reducing diaphragm (19) as the boundary, the spring seat (14), pressure-reducing spring (15), connecting seat assembly (16), pressure-reducing valve core (17), and pressure-reducing valve seat (18) are inside the pressure-reducing chamber, while the disc-shaped gasket (20) and support pad (21) are outside the pressure-reducing chamber. The disc-shaped gasket (20) and support pad (21) are both metal sheet structures and are fixed to the body (1) by bolts (30) to support the pressure-reducing diaphragm (19). The pressure-reducing diaphragm (19) is tightly attached to the disc-shaped gasket (20) under the action of the pressure inside the pressure-reducing chamber. After the regulating air flows into the second pressure reducing chamber (23), it flows through the second vent (27) to the valve hole (26). When the pressure of the regulating air is less than the limit value, the pressure reducing core is pressed against the valve hole (26) by the pressure reducing spring (15). When the pressure of the regulating air rises to the limit value, the pressure reducing core is pushed by the regulating air, the pressure reducing spring (15) is compressed, the pressure reducing valve core (17) moves away from the valve hole (26), and the regulating air flows from the gap between the pressure reducing valve core (17) and the valve hole (26) into the first vent (24) and the first pressure reducing chamber (22), and flows out to the outside through the pressure relief pipe.

2. The reduced-pressure flow amplifier for a signal feedback dual-acting positioner according to claim 1, characterized in that: The disc-shaped pad (20) and the support pad (21) are defined as a whole and called the support mechanism; the distance between the support mechanism and the spring seat (14) can be changed by rotating the bolt (30), thereby changing the pressure limit value of the regulating air.

3. The reduced-pressure flow amplifier for a signal feedback dual-acting positioner according to claim 1, characterized in that: The spring seat (14) is a cylindrical structure. The first vent (24) is located at the bottom of the cylindrical structure. The diameter of the first vent (24) is smaller than the diameter of the cylindrical structure. The central axis of the first vent (24) is parallel to the central axis of the cylindrical structure. The outer wall of the spring seat (14) has threads, and the spring seat (14) is connected to the body (1) through these threads; The pressure relief spring (15) is located inside the spring seat (14), and the direction of the spring force of the pressure relief spring (15) is parallel to the central axis of the vent hole (24).

4. The reduced-pressure flow amplifier for a signal feedback dual-acting positioner according to claim 1, characterized in that: When the pressure relief spring (15) is compressed to its shortest length by the regulating air, the pressure relief valve core (17) is still in the valve hole (26).

5. The reduced-pressure flow amplifier for a signal feedback dual-acting positioner according to claim 1, characterized in that: Observing along the central axis of vent hole one (24), the arrangement of some components of the flow amplifier is as follows: bolt (30), support pad (21), disc gasket (20), pressure reducing diaphragm (19), pressure reducing valve core (17), connecting seat assembly (16), pressure reducing spring (15), and spring seat (14).

6. The reduced-pressure flow amplifier for a signal feedback dual-acting positioner according to claim 1, characterized in that: Observing along the central axis of vent hole one (24), pressure relief chamber one (22) is located between adjustment chamber (7) and pressure relief chamber two (23).

7. The reduced-pressure flow amplifier for a signal feedback dual-acting positioner according to claim 1, characterized in that: A magnet (31) is provided on the double diaphragm assembly (2), and the magnet (31) moves together with the double diaphragm assembly (2); a magnetic field measurement module (32) is provided on the body (1) to measure the magnetic field strength of the magnet (31) and calculate the position of the magnet (31) based on the change in the magnetic field strength of the magnet (31).

Images