Air path structure for controlling pneumatic actuating mechanism and pneumatic actuating device

Abstract

The utility model relates to the technical field of valves, and provides a gas circuit structure for controlling a pneumatic actuating mechanism and a pneumatic actuating device. The gas circuit structure for controlling the pneumatic actuating mechanism comprises a positioner connected with the pneumatic actuating mechanism, a main gas circuit and a control gas circuit, the main gas circuit and the control gas circuit are connected with the positioner, and the main gas circuit is used for supplying gas to the pneumatic actuating mechanism through the positioner; the control gas circuit comprises a direction control valve connected with the positioner, a first sub gas circuit and a second sub gas circuit, the first sub gas circuit and the second sub gas circuit are connected with the direction control valve, and the direction control valve can enable one of the first sub gas circuit and the second sub gas circuit with the large gas supply pressure to be communicated with the positioner. And the positioner outputs the air supply pressure P0 of the main air path to the pneumatic executing mechanism according to the preset proportion. The gas circuit structure for controlling the pneumatic actuating mechanism is favorable for meeting the using working condition that the opening degree of a valve has the adjusting requirement, and can be favorable for stable development of actual industrial production operation.

Description

Technical Field

[0001] This utility model relates to the field of valve technology, and in particular to an air circuit structure for controlling a pneumatic actuator. This utility model also relates to a pneumatic actuator device equipped with the air circuit structure for controlling the pneumatic actuator. Background Technology

[0002] In existing technologies, the control air circuit is closely related to the valve and is a key link in achieving precise valve control and reliable operation. The control air circuit controls the movement of the pneumatic actuator by adjusting the pressure, flow rate, and direction of the compressed air supplied to it, thereby actuating the valve's opening and closing or adjusting its opening degree. For example, when it is necessary to increase the valve opening degree, the control air circuit increases the air pressure entering the pneumatic actuator, pushing the piston or diaphragm of the actuator to move, thus increasing the valve's opening degree; conversely, when it is necessary to decrease the valve opening degree, the control air circuit decreases the air pressure, causing the pneumatic actuator to move the valve towards the closing direction.

[0003] However, existing control pneumatic circuits can usually only achieve the full opening or full closing of pneumatic actuators (i.e., the full opening or full closing of valves), which is a single function and cannot meet the operating conditions where the valve opening needs to be adjusted, which is not conducive to the actual industrial production operation. Utility Model Content

[0004] In view of this, the present invention aims to propose an air circuit structure for controlling pneumatic actuators, which is beneficial for meeting the operating conditions where the valve opening size needs to be adjusted.

[0005] To achieve the above objectives, the technical solution of this utility model is implemented as follows:

[0006] An air circuit structure for controlling a pneumatic actuator includes a positioner connected to the pneumatic actuator, a main air circuit and a control air circuit connected to the positioner, wherein the main air circuit is used to supply air to the pneumatic actuator through the positioner;

[0007] The control air circuit includes a directional control valve connected to the positioner, and a first sub-air circuit and a second sub-air circuit respectively connected to the directional control valve. The directional control valve can connect the positioner to the first sub-air circuit and the second sub-air circuit with the larger supply air pressure, so that the positioner outputs the supply air pressure P0 of the main air circuit to the pneumatic actuator according to a preset ratio.

[0008] Furthermore, the gas supply pressure P1 of the first sub-gas circuit is less than the gas supply pressure P2 of the second sub-gas circuit.

[0009] Furthermore, the gas supply pressure P1 of the first sub-gas circuit and the gas supply pressure P2 of the second sub-gas circuit satisfy the following relationship: P1:P2=1:(1.8-2.5).

[0010] Furthermore, a first control valve for controlling the on / off state is connected in series in the first sub-gas line, and a second control valve for controlling the on / off state is connected in series in the second sub-gas line.

[0011] Furthermore, the end of the first sub-gas path furthest from the directional control valve is connected to a first sub-gas source, and the end of the second sub-gas path furthest from the directional control valve is connected to a second sub-gas source; the first control valve is located between the directional control valve and the first sub-gas source, and the second control valve is located between the directional control valve and the second sub-gas source.

[0012] Furthermore, a first filter pressure reducing valve is connected in series in the first sub-gas line, and the first filter pressure reducing valve is located between the first control valve and the first sub-gas source; and / or, a second filter pressure reducing valve is connected in series in the second sub-gas line, and the second filter pressure reducing valve is located between the second control valve and the second sub-gas source.

[0013] Furthermore, the first control valve and / or the second control valve are solenoid valves.

[0014] Furthermore, the positioner is a pneumatic positioner; and / or, the end of the main air path furthest from the positioner is connected to a main air source, and a main filter pressure reducing valve located between the main air source and the positioner is connected in series on the main air path.

[0015] Furthermore, the directional control valve is a shuttle valve or a slide valve.

[0016] Compared with the prior art, this utility model has the following advantages:

[0017] The pneumatic circuit structure for controlling the pneumatic actuator described in this utility model can be connected to the positioner and the first sub-air circuit and the second sub-air circuit with the larger supply air pressure by setting a directional control valve. This allows the positioner to output the main air circuit supply air pressure P0 to the pneumatic actuator according to a preset ratio, thereby facilitating the use conditions where the valve opening needs to be adjusted. This is beneficial for the stable operation of actual industrial production.

[0018] Furthermore, the pressure difference between the supply air pressure P1 of the first sub-circuit and the supply air pressure P2 of the second sub-circuit is P1:P2 = 1:(1.8-2.5), which is particularly suitable for applications requiring valves to be partially or fully open. The presence of a first control valve and a second control valve facilitates the control of the on / off state of the first and second sub-circuit air paths. The presence of a first or second filter pressure reducing valve filters impurities from the medium in either the first or second sub-circuit and stabilizes the output pressure, ensuring the stability of the control air path and the safe operation of valves, pneumatic actuators, and other related structures. The directional control valve uses a shuttle valve or slide valve, which has a simple structure and facilitates connection between the higher supply air pressure of the first and second sub-circuit air paths and the positioner.

[0019] Another objective of this utility model is to provide a pneumatic actuator, including a valve, a pneumatic actuator, and an air circuit structure for controlling the pneumatic actuator as described above.

[0020] The pneumatic actuator is connected to the valve, and the main air path, the first sub-air path, and the second sub-air path are all connected to the pneumatic actuator through the positioner, so as to control the opening and closing of the valve through the pneumatic actuator.

[0021] The pneumatic actuator of this utility model is provided with the above-mentioned air passage structure for controlling the pneumatic actuator, which has the same beneficial effect as the traditional technology, and will not be described in detail here. Attached Figure Description

[0022] The accompanying drawings, which form part of this utility model, are used to provide a further understanding of the utility model. The illustrative embodiments of the utility model and their descriptions are used to explain the utility model and do not constitute an undue limitation of the utility model. In the drawings:

[0023] Figure 1 This is a schematic diagram of the air circuit structure for controlling the pneumatic actuator as described in an embodiment of the present invention;

[0024] Explanation of reference numerals in the attached figures:

[0025] 10. Pneumatic actuator; 20. Positioner;

[0026] 30. Main air path; 31. Main air source; 32. Main filter pressure reducing valve;

[0027] 40. Control air path; 41. Directional control valve; 42. First sub-air path; 421. First control valve; 422. First sub-air source; 423. First filter pressure reducing valve; 43. Second sub-air path; 431. Second control valve; 432. Second sub-air source; 433. Second filter pressure reducing valve. Detailed Implementation

[0028] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments of the present invention can be combined with each other.

[0029] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0030] In the description of this utility model, it should be noted that if terms such as "upper," "lower," "inner," or "outer" appear, indicating orientation or positional relationship, they are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not 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 utility model. Furthermore, if terms such as "first" or "second" appear, they are also used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] Furthermore, in the description of this utility model, unless otherwise explicitly defined, the terms "installation," "connection," "joining," and "connector" 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 utility model in light of the specific circumstances.

[0032] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0033] Example 1

[0034] This embodiment relates to an air circuit structure for controlling a pneumatic actuator. In terms of overall structure, as follows: Figure 1 As shown, it includes a positioner 20 connected to the pneumatic actuator 10, a main air passage 30 and a control air passage 40 connected to the positioner 20, and the main air passage 30 is used to supply air to the pneumatic actuator 10 through the positioner 20.

[0035] Furthermore, the control air path 40 includes a directional control valve 41 connected to the positioner 20, and a first sub-air path 42 and a second sub-air path 43 respectively connected to the directional control valve 41. The directional control valve 41 can connect the positioner 20 with the one with the higher supply air pressure in the first sub-air path 42 and the second sub-air path 43, so that the positioner 20 outputs the supply air pressure P0 of the main air path 30 to the pneumatic actuator 10 according to a preset ratio.

[0036] At this time, as set above, the positioner 20 and the first sub-air circuit 42 and the second sub-air circuit 43 with the larger air pressure can be connected by setting the directional control valve 41, so that the positioner 20 outputs the main air circuit 30 air pressure P0 to the pneumatic actuator 10 according to the preset ratio, which is conducive to meeting the operating conditions where the valve opening size needs to be adjusted, thereby facilitating the stable operation of actual industrial production.

[0037] Based on the above description, in detail, in this embodiment, when implemented, the pneumatic actuator 10 can preferably be a single-acting pneumatic actuator 10. In addition to using a single-acting pneumatic actuator 10, other actuators with similar requirements can also be used, such as a double-acting pneumatic actuator 10.

[0038] In this embodiment, as a preferred implementation, the supply air pressure P1 of the first sub-air passage 42 is less than the supply air pressure P2 of the second sub-air passage 43. Thus, when the first sub-air passage 42 is open and the second sub-air passage 43 is closed, because the supply air pressure P1 of the first sub-air passage 42 is greater than 0, the directional control valve 41 can connect the first sub-air passage 42 and the positioner 20, so that the positioner 20 outputs the supply air pressure P0 of the main air passage 30 to the pneumatic actuator 10 according to a first preset ratio. When the second sub-air passage 43 is open and the first sub-air passage 42 is closed, because the supply air pressure P2 of the second sub-air passage 43 is greater than 0, the directional control valve 41 can connect the second sub-air passage 43 and the positioner 20, so that the positioner 20 outputs the supply air pressure P0 of the main air passage 30 to the pneumatic actuator 10 according to a second preset ratio.

[0039] Furthermore, when both the first sub-air passage 42 and the second sub-air passage 43 are open, because the air supply pressure P2 of the second sub-air passage 43 is greater than the air supply pressure P1 of the first sub-air passage 42, the directional control valve 41 can connect the second sub-air passage 43 and the positioner 20, so that the positioner 20 outputs the air supply pressure P0 of the main air passage 30 to the pneumatic actuator 10 according to the third preset ratio. Here, P0 can be the maximum air supply pressure value of the main air passage 30, P0 under the first preset ratio can be less than P0 under the second preset ratio, and P0 under the second preset ratio can be equal to P0 under the third preset ratio. The advantage of this setting is that by adjusting the values ​​of P1 and P2, the proportion of the air supply pressure P0 of the main air passage 30 output to the pneumatic actuator 10 can be adjusted, thereby controlling the pneumatic actuator 10 (i.e., the valve) to achieve different opening sizes, that is, meeting the different opening size requirements of the pneumatic actuator 10 (i.e., the valve).

[0040] In a specific implementation, in this embodiment, as a preferred embodiment, the air supply pressure P1 of the first sub-air passage 42 and the air supply pressure P2 of the second sub-air passage 43 satisfy the following relationship: P1:P2 = 1:(1.8-2.5). For example, P1 and P2 can be specifically taken as 7PSI or 14PSI, and 7PSI or 15PSI, etc., respectively. Thus, P0 under the second preset ratio corresponds to the fully open opening of the pneumatic actuator 10 (i.e., the valve), and P0 under the first preset ratio corresponds to the half-open opening of the pneumatic actuator 10 (i.e., the valve), which is particularly suitable for meeting the operating conditions where the valve needs to be half-open and fully open.

[0041] Furthermore, in this embodiment, as a preferred implementation, a first control valve 421 for controlling the on / off state is connected in series on the first sub-gas passage 42, and a second control valve 431 for controlling the on / off state is connected in series on the second sub-gas passage 43. The arrangement of the first control valve 421 and the second control valve 431 facilitates the control of the on / off state of the first sub-gas passage 42 and the second sub-gas passage 43.

[0042] Furthermore, as a preferred embodiment, both the first control valve 421 and the second control valve 431 in this embodiment can be solenoid valves, especially two-position three-way solenoid valves, in order to facilitate the control of the opening and closing of the first sub-gas passage 42 and the second sub-gas passage 43.

[0043] Furthermore, in this embodiment, as a preferred implementation, the end of the first sub-gas path 42 away from the directional control valve 41 is connected to the first sub-gas source 422, and the end of the second sub-gas path 43 away from the directional control valve 41 is connected to the second sub-gas source 432. The first control valve 421 is located between the directional control valve 41 and the first sub-gas source 422, and the second control valve 431 is located between the directional control valve 41 and the second sub-gas source 432.

[0044] In this embodiment, as a preferred implementation, a first filter and pressure reducing valve 423 is connected in series on the first sub-gas path 42, and the first filter and pressure reducing valve 423 is located between the first control valve 421 and the first sub-gas source 422. A second filter and pressure reducing valve 433 is connected in series on the second sub-gas path 43, and the second filter and pressure reducing valve 433 is located between the second control valve 431 and the second sub-gas source 432.

[0045] It is understandable that the first filter pressure reducing valve 423 or the second filter pressure reducing valve 433 can filter impurities in the medium of the first sub-gas circuit 42 or the medium of the second sub-gas circuit 43 and stabilize the output pressure, so as to ensure the stability of the control gas circuit 40 and the safe use of valves, pneumatic actuators 10 and other related structures.

[0046] In addition, in this embodiment, as a preferred implementation, the positioner 20 is a pneumatic positioner 20, that is, a pneumatic valve positioner. It can not only realize the output of the main air circuit 30 supply air pressure P0 in different proportions according to the supply air pressure P1 of the first sub-air circuit 42 and the supply air pressure P2 of the second sub-air circuit 43, but also has the advantages of high precision, reliability and speed, intrinsic safety, low maintenance cost, large output force and good compatibility, thus improving the use effect of the air circuit structure used to control the pneumatic actuator.

[0047] Meanwhile, the end of the main air passage 30 furthest from the positioner 20 is connected to the main air source 31, and preferably, a main filter pressure reducing valve 32 is connected in series on the main air passage 30 between the main air source 31 and the positioner 20. This main filter pressure reducing valve 32 can filter impurities in the medium of the main air passage 30 and stabilize the output pressure, so as to ensure the stability of the main air passage 30, that is, the stability of the pneumatic actuator 10 (i.e., the valve) during the opening and closing process.

[0048] Furthermore, in this embodiment, as a preferred implementation, the directional control valve 41 is a shuttle valve or a slide valve. The use of a shuttle valve or slide valve for the directional control valve 41 here is simple in structure and facilitates the connection of the one with the higher air pressure in the first sub-air circuit 42 and the second sub-air circuit 43 to the positioner 20.

[0049] In addition, it is worth mentioning that in the existing technology, the control air path 40 is closely related to the valve and is a key link in achieving precise valve control and reliable operation. Furthermore, the application fields of the control air path 40, pneumatic actuator 10, and valve are quite extensive. Specifically, in the fields of chemical and pharmaceutical manufacturing, many process steps require extremely high precision in controlling fluid flow and pressure. For example, in the pharmaceutical process, the amount of raw materials added to the reactor needs to be precisely adjusted in real time according to factors such as temperature and reaction progress to control the feed rate, ensuring accurate proportions of drug components. If the control air path 40 cannot flexibly adjust the valve opening, it will be difficult to accurately control the input and output of materials, leading to unstable reaction processes, large fluctuations in product quality, increased scrap rates, and potentially extended production cycles and reduced overall production efficiency due to improper flow control.

[0050] In some systems involving fluid transport, such as heating and water supply systems, valve opening needs to be adjusted to control flow rate according to actual needs. If the control air circuit 40 can only achieve fully open or fully closed valves, the system cannot fine-tune the flow rate according to the actual load. Under low-load conditions, the valve remains fully open, resulting in significant energy waste, increasing operating costs, and contradicting the trend of energy conservation and emission reduction.

[0051] In complex industrial automation control systems, the coordinated operation of each component relies on precise parameter control. A single-function control circuit 40 prevents valves from flexibly adjusting their opening according to system changes, disrupting the system's dynamic balance. For example, in large petrochemical plants, multiple process units are interconnected. Inaccurate valve opening can affect the transfer of materials and energy throughout the entire process, triggering a chain reaction, leading to system instability, increasing the probability of malfunctions, and potentially forcing the entire production unit to shut down for maintenance.

[0052] Meanwhile, when the control air circuit 40 cannot meet the valve opening adjustment requirements, the system may experience frequent pressure surges during operation. For example, in a gas transmission pipeline, a valve suddenly opening or closing completely can trigger a water hammer effect, generating a large impact force that causes impact and vibration on the pipeline, valve, and related equipment, accelerating equipment wear and aging, shortening equipment lifespan, increasing equipment maintenance and replacement costs, and may even lead to safety accidents such as pipeline rupture and valve seal damage.

[0053] Therefore, it is crucial that the control air circuit 40 meets the operating conditions where the valve opening needs adjustment. The air circuit structure for controlling the pneumatic actuator in this embodiment solves the above problems through the cooperation of the directional control valve 41, the positioner 20, and multiple sub-air circuits. Of course, the air circuit structure for controlling the pneumatic actuator in this embodiment is particularly suitable for operating conditions where the valve needs to be half-open or fully open.

[0054] Example 2

[0055] This embodiment relates to a pneumatic actuator, including a valve, a pneumatic actuator 10, and an air circuit structure for controlling the pneumatic actuator as shown in Embodiment 1. The pneumatic actuator 10 is connected to the valve, and the main air circuit 30, the first sub-air circuit 42, and the second sub-air circuit 43 are all connected to the pneumatic actuator 10 via a positioner 20, so as to control the opening and closing of the valve through the pneumatic actuator 10.

[0056] The pneumatic actuator of this embodiment, by setting the air path structure for controlling the pneumatic actuator as in Embodiment 1, has the same beneficial effects as the conventional technology, and will not be described in detail here.

[0057] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A gas path structure for controlling a pneumatic actuator, characterized in that: it comprises a positioner (20) connected to a pneumatic actuator (10), a main gas path (30) and a control gas path (40) connected to the positioner (20), the main gas path (30) being used to supply the pneumatic actuator (10) with gas through the positioner (20); the control gas path (40) comprises a direction control valve (41) connected to the positioner (20), and a first sub-gas path (42) and a second sub-gas path (43) connected to the direction control valve (41) respectively, the direction control valve (41) being capable of connecting the one with higher gas pressure between the first sub-gas path (42) and the second sub-gas path (43) to the positioner (20), so that the positioner (20) outputs the gas pressure P0 of the main gas path (30) to the pneumatic actuator (10) according to a preset ratio. 2.The gas path structure for controlling a pneumatic actuator according to claim 1, characterized in that: the gas pressure P1 of the first sub-gas path (42) is less than the gas pressure P2 of the second sub-gas path (43). 3.The gas path structure for controlling a pneumatic actuator according to claim 2, characterized in that: the gas pressure P1 of the first sub-gas path (42) and the gas pressure P2 of the second sub-gas path (43) satisfy the following relationship: P1: P2 = 1: (1.8-2.5). 4.The gas path structure for controlling a pneumatic actuator according to claim 2, characterized in that: a first control valve (421) for controlling on-off is connected in series on the first sub-gas path (42), and a second control valve (431) for controlling on-off is connected in series on the second sub-gas path (43). 5.The gas path structure for controlling a pneumatic actuator according to claim 4, characterized in that: a first sub-gas source (422) is connected to the end of the first sub-gas path (42) away from the direction control valve (41), and a second sub-gas source (432) is connected to the end of the second sub-gas path (43) away from the direction control valve (41); the first control valve (421) is located between the direction control valve (41) and the first sub-gas source (422), and the second control valve (431) is located between the direction control valve (41) and the second sub-gas source (432). 6.The gas path structure for controlling a pneumatic actuator according to claim 5, characterized in that: a first filter pressure reducing valve (423) is connected in series on the first sub-gas path (42), and the first filter pressure reducing valve (423) is located between the first control valve (421) and the first sub-gas source (422); and / or, a second filter pressure reducing valve (433) is connected in series on the second sub-gas path (43), and the second filter pressure reducing valve (433) is located between the second control valve (431) and the second sub-gas source (432). 7.The gas path structure for controlling a pneumatic actuator according to claim 4, characterized in that: ​ ​ ​ ​ ​ ​ ​ ​ ​ The first control valve (421) and / or the second control valve (431) is an electromagnetic valve.

8. The air path structure for controlling a pneumatic actuator according to claim 1, characterized in that: The positioner (20) is a pneumatic positioner (20); and / or, The main air path (30) is connected with a main air source (31) at an end away from the positioner (20), and a main filter pressure reducing valve (32) is connected in series on the main air path (30) between the main air source (31) and the positioner (20).

9. The air path structure for controlling a pneumatic actuator according to any one of claims 1 to 8, characterized in that: The directional control valve (41) is a shuttle valve or a slide valve.

10. A pneumatic actuating device, characterized in that: It comprises a valve, a pneumatic actuator (10), and an air path structure for controlling a pneumatic actuator according to any one of claims 1 to 9; The pneumatic actuator (10) is connected with the valve, and the main air path (30), the first sub-air path (42) and the second sub-air path (43) are all connected with the pneumatic actuator (10) through the positioner (20) to control the opening and closing of the valve through the pneumatic actuator (10).

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