Pneumatic butterfly valve double-limit detection device and detection method

Abstract

The invention discloses a double-limit detection device and a double-limit detection method for a pneumatic butterfly valve, and belongs to the technical field of action signal detection of movable butterfly valves. According to the double-limit detection device for the pneumatic butterfly valve, two fixed bases are arranged on a non-driving end shaft detection valve seat, magnetic proximity switches are installed on the bases respectively, a metal rocker is fixed to a valve shaft, and a magnet is installed on the metal rocker; two fixing bases are arranged on the two sides of the driving end shaft measuring valve seat, mechanical limiting switches are installed on the fixing bases respectively, a swing plate is arranged on the valve shaft, and a metal baffle is arranged on the swing plate. The problems that an existing microswitch is prone to being abraded, the fault rate is high when the microswitch works in the severe environment, and the fault recovery time is long are solved. According to the limiting device, the inherent defects of microswitch limiting can be overcome, the reliability of the limiting switch is improved, the requirements of the converter gas holder for the operation reliability and stability of the inlet header pipe butterfly valve are met, the maintenance time can be shortened when a certain limiting position breaks down, and energy waste is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of pneumatic butterfly valve action signal detection, in particular to a pneumatic butterfly valve double limit detection device and a detection method. Background Art

[0002] Pneumatic butterfly valves are widely used in industrial process control, especially in scenarios where frequent switching and precise flow regulation are required. Valve limit switches are key components to ensure accurate valve movement, and micro switches are traditionally used for position feedback. However, traditional micro switches have several defects: their contact springs and spring components are prone to stress fatigue and failure under long-term and high-frequency operation; at the same time, the choice of installation location and environmental factors (such as dust, oil, moisture) will also affect the working reliability of micro switches.

[0003] The Chinese patent with the announcement number CN216742893U discloses a pneumatic butterfly valve with a limit connector, which includes an adjustment rod driven by an electric telescopic rod connected to an adjustment disk, and a filter screen is provided to filter the water source. Although this design improves the practicality and filtering performance of the device, its main focus is on water source filtering and mechanical adjustment, and it fails to fully solve the reliability problem in valve limit detection, especially the stability during long-term operation in harsh environments, and lacks support for the high-frequency switching operation common to pneumatic butterfly valves and stable operation under harsh working conditions.

[0004] The Chinese patent with announcement number CN218211959U discloses a double limit detector for hoisting machinery. This device realizes remote monitoring and data collection through a wireless transmission module, which can effectively monitor the status of the height limit device of the crane and avoid accidents caused by improper configuration or damage. However, the patent emphasizes the status monitoring of the height limit device, lacks optimization for the characteristics of pneumatic butterfly valves, and does not specifically mention how to quickly respond to the fault switching of the limit detection system, which cannot meet the requirements of pneumatic butterfly valves for rapid response in energy regulation and safe operation. Summary of the invention

[0005] The purpose of the present invention is to provide a pneumatic butterfly valve double limit detection device and detection method, which can not only overcome the inherent defects of the microswitch limit, improve the reliability of the limit switch, and ensure the requirements of the converter gas holder for the operating reliability and stability of the inlet main butterfly valve, but also reduce maintenance time and reduce energy waste when a certain limit fails, thereby solving the problems raised in the above-mentioned background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A pneumatic butterfly valve double limit detection device, comprising a non-driving end axial valve seat and a driving end axial valve seat, the non-driving end axial valve seat is provided with a first fixed base and a second fixed base, the positions of the first fixed base and the second fixed base correspond to the fully open and fully closed positions of the valve, the first fixed base and the second fixed base are respectively installed with a first magnetic proximity switch and a second magnetic proximity switch, a metal rocker is fixed on the valve shaft close to the non-driving end axial valve seat, and a magnet is installed on the outer end of the metal rocker;

[0008] A third fixed base and a fourth fixed base are provided on both sides of the drive end axial valve seat, and the third fixed base and the fourth fixed base correspond to the fully open and fully closed positions of the valve, and the first mechanical limit switch and the second mechanical limit switch are respectively installed on the third fixed base and the fourth fixed base, and a rocker plate is provided on the valve shaft close to the drive end axial valve seat, and a metal baffle is provided on one side of the rocker plate.

[0009] Preferably, the rotation angle stroke of the metal rocker is the same as the action stroke of the valve, and the maximum rotation angle is 90°.

[0010] Preferably, the rotation angle stroke of the metal baffle is the same as the action stroke of the valve, and the maximum rotation angle is 90°.

[0011] Preferably, the device also includes a control electrical circuit for performing dual limit detection, and when the first magnetic proximity switch or the second magnetic proximity switch fails, the valve switch state is identified by pulling open the selection switch QF2 and closing the selection switch QF1 to switch to the first mechanical limit switch and the second mechanical limit switch.

[0012] A detection method for a pneumatic butterfly valve double limit detection device is implemented based on a pneumatic butterfly valve double limit detection device, comprising the following steps:

[0013] Step 1: When the pneumatic butterfly valve is in working state, its opening or closing process is performed by the cylinder. During this process, the valve shaft rotates, thereby driving the metal rocker and metal baffle to move;

[0014] Step 2: For the first mechanical limit switch or the second mechanical limit switch, when the valve reaches the preset fully open or fully closed position, the metal baffle will touch the first mechanical limit switch or the second mechanical limit switch to cause the switch to operate, thereby generating an electrical signal, which is transmitted to the electrical control circuit of the valve as a confirmation signal that the valve has reached the specified position;

[0015] Step 3: For the first magnetic proximity switch and the second magnetic proximity switch, as the valve shaft rotates, the magnet on the metal rocker will approach or move away from the first magnetic proximity switch or the second magnetic proximity switch. When the magnet moves to the position of the first magnetic proximity switch or the second magnetic proximity switch, the switch detects the change in the magnetic field and outputs a 24V high-level signal. This signal is also sent to the electrical control circuit to indicate the position status of the valve.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. The present invention adopts a non-contact proximity switch, which has no direct contact with mechanical parts and no wear, thus avoiding the mechanical wear and stress fatigue problems caused by frequent actions of traditional mechanical limit switches, and has a long service life. The proximity switch is packaged as a whole and is not easily affected by environmental factors such as dust, oil, and moisture. Therefore, it can work more reliably in harsh environments, and there is basically no failure during operation;

[0018] 2. The present invention has a manual limit switching function through a dual limit detection system. When one signal fails, it can be manually switched to a normal signal, which greatly reduces the fault recovery time and plays a key role in energy regulation and safe operation of gas cabinets.

[0019] 3. The present invention adopts a swing arm type first mechanical limit switch or a second mechanical limit switch. Although it cannot completely overcome the influence of mechanical fatigue, it can effectively reduce the impact of valve movement and extend the service life by adjusting the position of the swing arm.

[0020] 4. The present invention designs a control electrical circuit that allows manual switching to another normally working limit mode by selecting a switch when a magnetic proximity switch or a mechanical limit switch fails, ensuring that the system can complete fault recovery without interrupting operation, thereby improving the continuity and reliability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the side portion of the valve seat measured from the non-driving end of the present invention;

[0022] Figure 2 This is a front view of the non-driving end isometric valve seat of the present invention;

[0023] Figure 3 This is a front view of the isometric valve seat at the driving end of the present invention;

[0024] Figure 4 It is a schematic diagram of the control electrical circuit of the present invention.

[0025] In the figure: 1. Axial valve seat at non-driving end; 2. Axial valve seat at driving end; 3. First fixed base; 4. Second fixed base; 5. First magnetic proximity switch; 6. Second magnetic proximity switch; 7. Valve shaft; 8. Metal rocker; 9. Magnet; 10. Third fixed base; 11. Fourth fixed base; 12. First mechanical limit switch; 13. Second mechanical limit switch; 14. Metal baffle; 15. Rocker. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] In order to solve the problems of existing micro switches that are prone to wear, high failure rate when working in harsh environments, and long failure recovery time, please refer to Figure 1-4 , this embodiment provides the following technical solutions:

[0028] A pneumatic butterfly valve double limit detection device comprises a non-driving end axial valve seat 1 and a driving end axial valve seat 2. The non-driving end axial valve seat 1 is provided with a first fixed base 3 and a second fixed base 4. The positions of the first fixed base 3 and the second fixed base 4 correspond to the fully open and fully closed positions of the valve. The first fixed base 3 and the second fixed base 4 are respectively provided with a first magnetic proximity switch 5 and a second magnetic proximity switch 6 for sensing changes in the surrounding magnetic field.

[0029] The first magnetic proximity switch 5 and the second magnetic proximity switch 6 are integrally packaged, and are not easily affected by dust, oil, moisture, etc., and have basically zero failure during operation.

[0030] A metal rocker 8 is fixed on the valve shaft 7 near the non-driving end axial valve seat 1, and a magnet 9 is installed on the outer end of the metal rocker 8. The magnet 9 moves with the rotation of the valve shaft 7. When it rotates to the adjacent position, it can trigger the first magnetic proximity switch 5 or the second magnetic proximity switch 6, thereby realizing non-contact detection of the opening and closing state of the valve.

[0031] A third fixed base 10 and a fourth fixed base 11 are provided on both sides of the driving end axial valve seat 2. The third fixed base 10 and the fourth fixed base 11 correspond to the fully open and fully closed positions of the valve. The first mechanical limit switch 12 and the second mechanical limit switch 13 are respectively installed on the third fixed base 10 and the fourth fixed base 11. A rocker plate 15 is provided on the valve shaft 7 close to the driving end axial valve seat 2, and a metal baffle 14 is provided on one side of the rocker plate 15.

[0032] The rotation angle of the metal rocker 8 is the same as the action stroke of the valve, and the maximum rotation angle is 90°; the rotation angle of the metal baffle 14 is the same as the action stroke of the valve, and the maximum rotation angle is 90°.

[0033] The device also includes a control electrical circuit for receiving switch signals of the first magnetic proximity switch 5 and the second magnetic proximity switch 6, the first mechanical limit switch 12 and the second mechanical limit switch 13, and transmitting these signals to the control system to realize state feedback.

[0034] The control electrical circuit can realize dual limit detection. When one path fails, it can be manually switched to another normal working limit. For example, when the first magnetic proximity switch 5 or the second magnetic proximity switch 6 fails, the valve switch state can be identified by pulling open the selection switch QF2 and closing the selection switch QF1 to switch to the first mechanical limit switch 12 and the second mechanical limit switch 13.

[0035] Intermediate relays KAO / KAC and KK are used to switch the working mode according to the received signals and feed back the status information to the control loop and remote signal.

[0036] Manual switching can be completed without interrupting system operation, thereby significantly reducing fault recovery time, which plays a key role in energy regulation and safe operation of gas cabinets.

[0037] A detection method for a pneumatic butterfly valve double limit detection device is implemented based on a pneumatic butterfly valve double limit detection device, comprising the following steps:

[0038] Step 1: When the pneumatic butterfly valve is in working state, its opening or closing process is performed by the cylinder. During this process, the valve shaft 7 rotates accordingly, thereby driving the metal rocker 8 and the metal baffle 14 to move;

[0039] Step 2: For the first mechanical limit switch 12 or the second mechanical limit switch 13, when the valve reaches the preset fully open or fully closed position, the metal baffle 14 will touch the first mechanical limit switch 12 or the second mechanical limit switch 13 to cause the switch to operate, thereby generating an electrical signal, which is transmitted to the electrical control circuit of the valve as a confirmation signal that the valve has reached the specified position;

[0040] Step 3: For the first magnetic proximity switch 5 and the second magnetic proximity switch 6, as the valve shaft 7 rotates, the magnet 9 on the metal rocker 8 will approach or move away from the first magnetic proximity switch 5 or the second magnetic proximity switch 6. When the magnet 9 moves to the position of the first magnetic proximity switch 5 or the second magnetic proximity switch 6, the switch detects the change in the magnetic field and outputs a 24V high-level signal. This signal is also sent to the electrical control circuit to indicate the position status of the valve.

[0041] After the electrical control circuit receives the signal from the first magnetic proximity switch 5 or the second magnetic proximity switch 6, the first mechanical limit switch 12 or the second mechanical limit switch 13, it will trigger the corresponding intermediate relay to act. For example, the KAO / KAC coil loses power, and then its normally closed contacts close to drive the intermediate relay KK to act. This step not only completes the local status confirmation, but also transmits the status signal to the control system through the auxiliary contacts, participating in the automatic control process.

[0042] If the first magnetic proximity switch 5 or the second magnetic proximity switch 6 fails, the circuit connection of the magnetic proximity switch can be disconnected by pulling QF2, and the circuit of the mechanical limit switch can be activated by closing QF1, so as to quickly restore the normal operation of the valve. Conversely, if the first mechanical limit switch 12 or the second mechanical limit switch 13 fails, the first magnetic proximity switch 5 or the second magnetic proximity switch 6 can also be relied on to continue working by switching the selection switch.

[0043] In addition, the positions of the first magnetic proximity switch 5, the second magnetic proximity switch 6, the first mechanical limit switch 12 and the second mechanical limit switch 13 can be adjusted according to actual needs to reduce the impact on the limit switch when the valve is actuated and extend the service life of the equipment.

[0044] Working principle: When the pneumatic butterfly valve is opened or closed, the valve shaft 7 is driven by the driving device to rotate, and the metal baffle 14 and the metal rocker 8 on the valve shaft 7 move accordingly. When the valve reaches the preset fully open or fully closed position, the metal baffle 14 touches the first mechanical limit switch 12 or the second mechanical limit switch 13, triggering the limit switch action. The generated electrical signal is transmitted to the electrical control circuit to confirm that the valve has reached the specified position and participates in the chain reaction in the control system.

[0045] As the valve shaft 7 rotates, the magnet 9 on the metal rocker 8 approaches or moves away from the first magnetic proximity switch 5 or the second magnetic proximity switch 6, causing the switch to output a 24V high-level signal, indicating the position status of the valve. The electrical control circuit receives signals from the first magnetic proximity switch 5 and the second magnetic proximity switch 6, or the first mechanical limit switch 12 and the second mechanical limit switch 13, triggers the corresponding intermediate relay KAO / KAC to operate, and feeds back the status signal to the valve control loop and the remote control system to achieve automatic control.

[0046] The device is equipped with selector switches QF1 and QF2, which allow the operator to quickly switch to another normally working limit mode when a limit failure occurs in one route, ensuring the continuous operation of the system.

[0047] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0048] While the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that many changes, modifications, substitutions and variations can be made to the embodiments without departing from the principles and spirit of the invention.

Claims

1. A pneumatic butterfly valve double limit detection device, comprising a non-driving end axial valve seat (1) and a driving end axial valve seat (2), characterized in that: The non-driving end axial valve seat (1) is provided with a first fixed base (3) and a second fixed base (4), the positions of the first fixed base (3) and the second fixed base (4) correspond to the fully open and fully closed positions of the valve, the first fixed base (3) and the second fixed base (4) are respectively installed with a first magnetic proximity switch (5) and a second magnetic proximity switch (6), a metal rocker (8) is fixed on the valve shaft (7) close to the non-driving end axial valve seat (1), and a magnet (9) is installed on the outer end of the metal rocker (8); A third fixed base (10) and a fourth fixed base (11) are provided on both sides of the drive end axial valve seat (2), the third fixed base (10) and the fourth fixed base (11) correspond to the fully open and fully closed positions of the valve, the third fixed base (10) and the fourth fixed base (11) are respectively installed with a first mechanical limit switch (12) and a second mechanical limit switch (13), a rocking plate (15) is provided on the valve shaft (7) close to the drive end axial valve seat (2), and a metal baffle (14) is provided on one side of the rocking plate (15).

2. A pneumatic butterfly valve double limit detection device according to claim 1, characterized in that: The rotation angle stroke of the metal rocker (8) is the same as the action stroke of the valve, and the maximum rotation angle is 90°.

3. A pneumatic butterfly valve double limit detection device according to claim 2, characterized in that: The rotation angle stroke of the metal baffle (14) is the same as the action stroke of the valve, and the maximum rotation angle is 90°.

4. A pneumatic butterfly valve double limit detection device according to claim 3, characterized in that: It also includes a control electrical circuit for performing dual limit detection and identifying the valve switch state by pulling open the selection switch QF2 and closing the selection switch QF1 to switch to the first mechanical limit switch (12) and the second mechanical limit switch (13) when the first magnetic proximity switch (5) or the second magnetic proximity switch (6) fails.

5. A detection method for a pneumatic butterfly valve double limit detection device, implemented based on a pneumatic butterfly valve double limit detection device according to any one of claims 1 to 4, characterized in that: The following steps are involved: Step 1: When the pneumatic butterfly valve is in working state, its opening or closing process is performed by the cylinder, during which the valve shaft (7) rotates, thereby driving the metal rocker (8) and the metal baffle (14) to move; Step 2: For the first mechanical limit switch (12) or the second mechanical limit switch (13), when the valve reaches a preset fully open or fully closed position, the metal baffle (14) touches the first mechanical limit switch (12) or the second mechanical limit switch (13) to cause a switch action, thereby generating an electrical signal, which is transmitted to the electrical control circuit of the valve as a confirmation signal that the valve has reached the specified position; Step 3: For the first magnetic proximity switch (5) and the second magnetic proximity switch (6), as the valve shaft (7) rotates, the magnet (9) on the metal rocker (8) will approach or move away from the first magnetic proximity switch (5) or the second magnetic proximity switch (6). When the magnet (9) moves to the position of the first magnetic proximity switch (5) or the second magnetic proximity switch (6), the switch detects the change in the magnetic field and outputs a 24V high-level signal. This signal is also sent to the electrical control circuit to indicate the position status of the valve.

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