Anti-suckback structure of high-vacuum electromagnetic valve

Abstract

The utility model discloses a kind of anti-suckback structure of high vacuum solenoid valve, the utility model relates to industrial vacuum system control and protection technical field.It includes: condensation buffer tank, the outer wall of the condensation buffer tank is connected with pneumatic valve through conveying pipe penetration, the outer wall of the pneumatic valve far from condensation buffer tank side is connected with vacuum detection transmitter through conveying pipe penetration;Through the cooperation of sealing plate, blocking ring and tension spring in one-way valve group, pressure reverse change can be responded, reverse flow of medium is blocked, when pressure in pipe rises suddenly, excess pressure can be released by pressure relief pipe and anti-suckback through one-way sealing, when suckback hazard is detected, PLC controller can control high vacuum solenoid valve to close, air valve pressure regulation, realize double protection, pneumatic valve and high vacuum solenoid valve are automatically closed after power off, conventional suckback and vacuum pump lubricating oil suckback can also be avoided respectively, cover normal operation, pressure sudden change, power outage scene.

Description

Technical Field

[0001] This utility model relates to the field of industrial vacuum system control and protection technology, specifically to an anti-backflow structure for a high vacuum solenoid valve. Background Technology

[0002] In actual operation, existing vacuum systems related to high-vacuum solenoid valves commonly face backflow issues. When the system experiences a sudden shutdown, vacuum pump failure, or a change in the gas extraction path, causing a rapid change in the pipe pressure, gas, condensate, or impurities in the exhaust gas treatment tank and vacuum pump can easily flow back to the upstream condensation buffer tank, and may even intrude into the core equipment to be processed, such as transformers and CLS systems. This backflow not only disrupts the vacuum environment, rendering the previous vacuuming process unusable, but can also lead to serious consequences such as decreased transformer insulation performance and damage to the accuracy of the CLS system. Furthermore, the backflow medium can contaminate critical control components such as pneumatic valves and check valves, shortening equipment lifespan and increasing maintenance costs and safety risks. Utility Model Content

[0003] (a) Technical problems to be solved To address the shortcomings of existing technologies, this invention provides an anti-backflow structure for a high-vacuum solenoid valve, solving the problem of backflow caused by sudden system shutdown, vacuum pump failure, or switching of the gas extraction path.

[0004] (II) Technical Solution To solve the above problems, this utility model achieves this through the following technical solution: an anti-backflow structure for a high-vacuum solenoid valve, comprising: a condensation buffer tank 4, wherein a pneumatic valve 3 is connected to the outer wall of the condensation buffer tank 4 via a conveying pipe; a vacuum detection transmitter 2 is connected to the outer wall of the pneumatic valve 3 on the side away from the condensation buffer tank 4 via a conveying pipe; a connecting pipe 15 is connected to the outer wall of the condensation buffer tank 4 away from the pneumatic valve 3; a one-way valve assembly 5 is fixedly connected to the inner wall of the connecting pipe 15; the one-way valve assembly 5 includes a connecting pipe 51, a blocking ring 54 is fixedly connected to the inner wall of the connecting pipe 51, a sealing plate 53 is attached to the outer wall of the blocking ring 54, and a sleeve 55 is fixedly connected to the sealing plate 53 near the outer wall of the blocking ring 54. A tension spring 52 is fixedly connected inside the sleeve 55. A pressure relief pipe is connected through the outer wall below the connecting pipe 51. A sealing plate 53 is also fixedly connected to the inner wall of the pressure relief pipe. Through the synergistic action of the sealing plate 53, the blocking ring 54 and the tension spring 52 in the one-way valve group 5, the pressure change inside the pipe can be responded to quickly, blocking the reverse flow of the medium and solving the backflow problem from the core component level. The addition of the pressure relief pipe and the matching use of the sealing plate 53 can not only alleviate the impact of sudden pressure change inside the pipe on the equipment, but also ensure that backflow does not occur during pressure relief, thus improving the safety of the structure operation. At the same time, the cooperation between the vacuum detection transmitter 2 and the pneumatic valve 3 can regulate the medium flow status in real time, providing auxiliary protection for backflow prevention. The complementary functions of the core components improve the reliability of backflow prevention.

[0005] Preferably, a Roots pump 7 is connected to the outer wall of the end of the connecting pipe 15 away from the condenser buffer tank 4. The outlet of the Roots pump 7 is connected to a high-vacuum solenoid valve 8 through a delivery pipe. The outer wall of the high-vacuum solenoid valve 8 away from the Roots pump 7 is connected to a vacuum pump 10 through a delivery pipe. A micro-moisture detector 9 is fixedly connected to the outer wall of the vacuum pump 10. The outlet of the vacuum pump 10 is connected to a tail gas treatment tank 12 through a delivery pipe. The multi-stage pumping of the Roots pump 7 and the vacuum pump 10 can improve the pumping efficiency and vacuum level of the system, meeting the requirements of high-vacuum conditions. The control capability of the high-vacuum solenoid valve 8 in a high-vacuum environment can reduce pressure fluctuations during operation switching and reduce the risk of backflow. The micro-moisture detector 9 can monitor the humidity of the medium in real time, avoiding excessive moisture from corroding equipment components or affecting the vacuum level, and extending the service life of the equipment. The application of the tail gas treatment tank 12 ensures that the exhaust gas is discharged in compliance with environmental protection requirements, balancing equipment performance and environmental friendliness.

[0006] Preferably, a vacuum transmitter 2 is also connected to the outer wall above the condensation buffer tank 4. A venting valve 16 is connected to the outer wall below the one-way valve group 5 of the condensation buffer tank 4. A level switch 17 is fixedly connected to the outer wall below the venting valve 16 of the condensation buffer tank 4. A drain valve 18 is connected to the outer wall below the condensation buffer tank 4. The detection end of the vacuum transmitter 2 extends to the inner wall of the delivery pipe. A transformer vacuum extraction port 1 is provided on the outer wall of the end of the vacuum transmitter 2 away from the pneumatic valve 3. The multi-position vacuum transmitter 2 can fully cover the condensation buffer tank 4. Vacuum monitoring of related pipelines reduces blind spots and improves the accuracy of pressure monitoring, providing more reliable data support for backflow prevention control. The combination of level switch 17 and drain valve 18 can promptly discharge accumulated liquid and impurities in condensate buffer tank 4, preventing excessive liquid accumulation from affecting the buffering effect or causing component corrosion, while also reducing the risk of backflow caused by liquid accumulation. The application of vent valve 16 can flexibly adjust the pressure in condensate buffer tank 4, maintain pressure stability, and further reduce the possibility of backflow caused by sudden pressure changes. The setting of transformer vacuum extraction interface 1 enables convenient connection with transformer vacuum system, improving the applicability of the structure.

[0007] Preferably, the outer wall of the condensation buffer tank 4, located below the transformer vacuum extraction port 1, is connected to a CLS vacuum extraction port 14. The CLS vacuum extraction port 14 and the condensation buffer tank 4 are connected via a conveying pipe. A pneumatic valve 3 is also connected to the inner wall of the conveying pipe between the CLS vacuum extraction port 14 and the condensation buffer tank 4. The detection end of the micro-moisture detector 9 is located inside the vacuum pump 10. A PLC controller 6 is fixedly connected to the outer wall of the condensation buffer tank 4. The arrangement of the CLS vacuum extraction port 14 and the independent pneumatic valve 3 allows the structure to simultaneously... The system is compatible with both transformer and CLS vacuum systems, enhancing its versatility and applicability. The built-in vacuum pump 10 at the detection end of the micro-moisture detector 9 reduces detection errors, improves the accuracy of moisture detection, and facilitates timely detection of abnormal medium humidity, preventing damage to the equipment. The PLC controller 6 serves as the control core, enabling centralized and coordinated control of all components. It can not only respond quickly to various monitoring data but also achieve flexible switching and coordinated operation of different pumping circuits, improving the automation and stability of the system and indirectly reducing the risk of backflow caused by human error.

[0008] Preferably, an exhaust outlet 11 is connected to the outer wall above the exhaust gas treatment tank 12, and a drain valve 13 is fixedly connected to the outer wall below the exhaust gas treatment tank 12. The PLC controller 6 is connected to the vacuum transmitter 2, pneumatic valve 3, Roots pump 7, high vacuum solenoid valve 8, micro-water detector 9, vacuum pump 10, gas leakage valve 16, and liquid level switch 17. The PLC controller 6 controls the start and stop of the entire equipment. The comprehensive connection between the PLC controller 6 and each component realizes the intelligent and automated control of the system, reduces manual intervention, and lowers the risk of human error. The system reduces the probability of errors and can quickly respond to various abnormal situations. By coordinating the actions of multiple components, it blocks backflow, improving the timeliness and reliability of backflow prevention. The coordination between the exhaust port 11 and the drain valve 13 ensures that the exhaust gas treatment tank 12 can effectively treat the exhaust gas and discharge the accumulated water in a timely manner, maintaining its treatment efficiency and preventing excessive water accumulation from affecting system operation. The integrity of the overall control loop ensures that the system is in a stable and controllable state throughout the entire process from startup, operation to shutdown. The functions of each component form a closed loop, which not only strengthens the backflow prevention effect but also improves the operational stability and service life of the entire structure.

[0009] (III) Beneficial Effects This invention provides an anti-backflow structure for a high-vacuum solenoid valve. It offers the following advantages: (I) The anti-backflow structure of this high-vacuum solenoid valve forms a full-process protection system through multiple anti-backflow mechanisms, including active blocking by a one-way valve assembly, buffer protection by a pressure relief pipe, intelligent coordination by a PLC, and automatic valve shut-off upon power failure. This enhances the reliability of anti-backflow protection. During normal operation, the synergistic action of the sealing plate, blocking ring, and tension spring in the one-way valve assembly can quickly respond to reverse pressure changes and directly block the reverse flow of the medium. When the pressure inside the pipe rises sharply, the pressure relief pipe can release excess pressure to protect the equipment and prevent backflow of external media through its one-way sealing characteristics. If a backflow hazard such as a sudden drop in vacuum is detected, the PLC controller can quickly control the high-vacuum solenoid valve to close urgently and the vent valve to adjust the pressure, achieving dual protection of emergency blocking and pressure balance. At the same time, the pneumatic valve and the high-vacuum solenoid valve automatically close when there is a sudden power failure, which can also prevent conventional backflow and backflow of vacuum pump lubricating oil, respectively. This comprehensively covers the backflow risks in multiple scenarios such as normal operation, sudden pressure changes, and sudden power failures, providing core protection for the stable operation of the high-vacuum system.

[0010] (II) The anti-backflow structure of this high-vacuum solenoid valve, through the dual interfaces of the transformer vacuum pumping interface and the CLS vacuum pumping interface, combined with an independently controlled pneumatic valve, can flexibly connect to both transformer and CLS vacuum systems, expanding the range of applicable scenarios; and the adaptation of multi-stage pumping and high-vacuum solenoid valve can improve the system vacuum level and reduce airflow fluctuations, meeting the requirements of high-vacuum working conditions. The system ensures operational stability through multi-dimensional monitoring and intelligent control: the multi-position vacuum detection transmitter can accurately capture pressure changes, the liquid level switch and drain valve can promptly discharge accumulated liquid impurities, the micro-water detector can monitor the humidity of the medium in real time, and all kinds of data are centrally controlled through the PLC controller, which reduces manual intervention and operational errors, and can avoid problems such as equipment corrosion and vacuum level drop in advance; at the same time, the exhaust gas treatment tank and drain valve ensure compliant exhaust gas discharge and convenient cleaning of water in the tank. The overall structure improves operational stability while reducing maintenance difficulty and cost, taking into account practicality and economy. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This utility model Figure 1 Schematic diagram of the structure at point A; Figure 3 This is a schematic diagram of the structure of the planar flow chart of this utility model; Figure 4 This is a structural schematic diagram of the PLC control flowchart of this utility model.

[0012] In the diagram: 1. Transformer vacuum pumping interface; 2. Vacuum detection transmitter; 3. Pneumatic valve; 4. Condensation buffer tank; 5. One-way valve assembly; 51. Connecting pipe; 52. Tension spring; 53. Sealing plate; 54. Blocking ring; 55. Bushing; 6. PLC controller; 7. Roots pump; 8. High vacuum solenoid valve; 9. Micro-water detector; 10. Vacuum pump; 11. Tail gas discharge port; 12. Tail gas treatment tank; 13. Drain valve; 14. CLS vacuum pumping interface; 16. Infiltration valve; 15. Connecting pipe; 17. Liquid level switch; 18. Drain valve. Detailed Implementation

[0013] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0014] Please see Figure 1-4This utility model provides a backflow prevention structure for a high vacuum solenoid valve, comprising: a condensation buffer tank 4, a pneumatic valve 3 connected to the outer wall of the condensation buffer tank 4 via a conveying pipe, a vacuum detection transmitter 2 connected to the outer wall of the pneumatic valve 3 away from the condensation buffer tank 4 via a conveying pipe, a connecting pipe 15 connected to the outer wall of the condensation buffer tank 4 away from the pneumatic valve 3, and a one-way valve assembly 5 fixedly connected to the inner wall of the connecting pipe 15; the one-way valve assembly 5 includes a connecting pipe 51, a blocking ring 54 fixedly connected to the inner wall of the connecting pipe 51, a sealing plate 53 attached to the outer wall of the blocking ring 54, a sleeve 55 fixedly connected to the sealing plate 53 near the outer wall of the blocking ring 54, a tension spring 52 fixedly connected inside the sleeve 55, and a pressure relief pipe connected to the outer wall below the connecting pipe 51, the inner wall of the pressure relief pipe also fixedly connected to the sealing plate 53.

[0015] A Roots pump 7 is connected to the outer wall of the end of the connecting pipe 15 away from the condensation buffer tank 4. The outlet of the Roots pump 7 is connected to a high vacuum solenoid valve 8 through a delivery pipe. A vacuum pump 10 is connected to the outer wall of the high vacuum solenoid valve 8 away from the Roots pump 7 through a delivery pipe. A micro-water detector 9 is fixedly connected to the outer wall of the vacuum pump 10. The outlet of the vacuum pump 10 is connected to a tail gas treatment tank 12 through a delivery pipe.

[0016] A vacuum transmitter 2 is also connected to the outer wall above the condensing buffer tank 4. A venting valve 16 is connected to the outer wall below the one-way valve group 5 of the condensing buffer tank 4. A level switch 17 is fixedly connected to the outer wall below the venting valve 16 of the condensing buffer tank 4. A drain valve 18 is connected to the outer wall below the condensing buffer tank 4. The detection end of the vacuum transmitter 2 extends to the inner wall of the delivery pipe. A transformer vacuum extraction port 1 is provided on the outer wall of the end of the vacuum transmitter 2 away from the pneumatic valve 3.

[0017] The outer wall of the condensing buffer tank 4, located below the transformer vacuum extraction port 1, is connected to the CLS vacuum extraction port 14. The CLS vacuum extraction port 14 and the condensing buffer tank 4 are connected through a conveying pipe. The inner wall of the pipe connecting the CLS vacuum extraction port 14 and the condensing buffer tank 4 is also connected to a pneumatic valve 3. The detection end of the micro-water detector 9 is located inside the vacuum pump 10. The outer wall of the condensing buffer tank 4 is fixedly connected to the PLC controller 6.

[0018] The outer wall above the exhaust gas treatment tank 12 is connected to the exhaust gas discharge port 11, and the outer wall below the exhaust gas treatment tank 12 is fixedly connected to the drain valve 13. The PLC controller 6 channel wires are connected to the vacuum detection transmitter 2, pneumatic valve 3, Roots pump 7, high vacuum solenoid valve 8, micro water detector 9, vacuum pump 10, gas leakage valve 16 and liquid level switch 17. The PLC controller 6 controls the start and stop of the entire equipment.

[0019] In use, the anti-backflow structure of the high-vacuum solenoid valve 8 is centered on the condensation buffer tank 4. It establishes a medium delivery and anti-backflow channel through key components such as the connecting pipe 15 and the one-way valve group 5. Together with the vacuum pump 10 and the Roots pump 7, it forms a vacuum pumping system. The entire system is intelligently controlled by the PLC controller 6. The overall working principle revolves around five core stages: medium introduction, vacuum pumping, anti-backflow protection, system adjustment, and finally, exhaust gas treatment. Specifically, when the structure needs to be connected to a transformer vacuum system, the medium enters the delivery pipe through the transformer vacuum pumping interface 1, flows through the pneumatic valve 3, and then converges into the condensation buffer tank 4. If connected to C... In the LS vacuum system, the medium enters the condensation buffer tank 4 through the CLS vacuum pumping interface 14 and its matching independent pneumatic valve 3. The pneumatic valves 3 corresponding to the two types of interfaces can be opened and closed independently under the control of the PLC controller 6 to achieve the switching between different systems. During this stage, the vacuum detection transmitters 2 on the side and top of the condensation buffer tank 4 are started simultaneously. Because the detection end extends to the inner wall of the delivery pipe, it can capture the changes in vacuum degree in the pipe and tank in real time and transmit the data to the PLC controller 6 to provide initial data support for subsequent adjustment of vacuum pumping parameters. At the same time, it monitors the medium flow status in real time to avoid the risk of backflow caused by abnormal initial pressure.

[0020] Based on the initial vacuum data fed back by the vacuum transmitter 2, the PLC controller 6 first starts the vacuum pump 10 to provide basic pumping power for the system, creating a negative pressure environment in the condensation buffer tank 4. This pushes the medium inside the tank towards the connecting pipe 15. When the medium enters the one-way valve group 5 inside the connecting pipe 15, the medium pressure overcomes the elastic force of the tension spring 52 in the one-way valve group 5, pushing the sealing plate 53 to separate from the blocking ring 54. The medium then flows smoothly to the Roots pump 7 through the connecting pipe 51. As the system vacuum gradually increases to the preset threshold, the PLC controller 6 starts the Roots pump 7, forming a multi-stage pumping combination with the vacuum pump 10 to improve pumping efficiency and quickly raise the system vacuum to the high vacuum operating condition requirements. The sleeve 55 provides guidance and sliding space for the sealing plate 53. During this process, the high vacuum solenoid valve 8 remains open, providing a stable channel for the airflow between the Roots pump 7 and the vacuum pump 10, ensuring that the medium is continuously delivered towards the vacuum pump 10. At the same time, its high vacuum environment adaptability can reduce airflow fluctuations and reduce the risk of pressure sudden changes.

[0021] Backflow prevention is a core function of the system. It is protected by a triple system, consisting of active protection from the check valve group 5, auxiliary protection from the pressure relief pipe, and collaborative protection from the PLC controller 6. The check valve group 5 actively blocks backflow, and the pneumatic valve 3 and high-vacuum solenoid valve 8 automatically close when there is a sudden power failure, preventing backflow and backflow of lubricating oil from the vacuum pump 10, respectively. During normal transport, the sealing plate 53 is in the open state due to the positive pressure of the medium. When the system experiences a reverse pressure change, such as a sudden shutdown of the vacuum pump 10 or a change in operating conditions that causes the downstream pressure to be higher than the upstream pressure, the elastic force of the tension spring 52 quickly drives the sealing plate 53 to reset and fit tightly against the blocking ring 54, directly blocking the reverse flow path of the medium and preventing backflow from occurring at the core component level.

[0022] The pressure relief pipe provides pressure buffer protection. If the pressure inside the pipe suddenly increases during the transportation process, such as a sudden increase in the flow rate of the medium or a partial blockage in the pipeline, the pressure relief pipe below the connecting pipe 51 will be activated. The high pressure inside the pipe will push the sealing plate 53 inside the pressure relief pipe to open, releasing excess pressure and preventing damage to components such as the condensation buffer tank 4 and the connecting pipe 15 due to excessive pressure. Furthermore, the sealing plate 53 inside the pressure relief pipe has the same structure as the internal structure of the connecting pipe 51, always maintaining a one-way sealing characteristic to prevent external media from being drawn back into the system through the pressure relief pipe.

[0023] The intelligent collaborative protection of the PLC controller 6 is as follows: when the vacuum transmitter 2 detects a sudden drop in the vacuum level inside the pipe, indicating a risk of backflow, it immediately transmits the signal to the PLC controller 6. The controller responds quickly, controlling the high vacuum solenoid valve 8 to close urgently, blocking the airflow channel between the Roots pump 7 and the vacuum pump 10, and reducing the reverse impact of the downstream medium. On the other hand, it adjusts the gas leakage valve 16 to open moderately, introducing a small amount of gas to fine-tune the pressure inside the condensation buffer tank 4, avoiding excessive negative pressure inside the tank that could cause backflow. Through the coordinated action of emergency blocking and pressure balancing, the anti-backflow effect is strengthened.

[0024] During continuous system operation, all auxiliary components work synchronously to maintain equipment stability and backflow prevention reliability. For liquid level and impurity regulation, the liquid level switch 17 on the outer wall of the condensation buffer tank 4 monitors the liquid accumulation inside the tank in real time. When the liquid reaches a preset height, the liquid level switch 17 sends a signal to the PLC controller 6, which then controls the drain valve 18 to open, promptly discharging the accumulated liquid and impurities. This prevents excessive liquid accumulation from affecting the buffering effect of the condensation buffer tank 4 and also prevents backflow due to pressure fluctuations, reducing the risk of backflow. For medium humidity monitoring, the micro-moisture detector 9 inside the vacuum pump 10 continuously monitors the moisture content of the medium. If excessive moisture is detected, it may lead to equipment corrosion and a decrease in vacuum. After the data is fed back to the PLC controller 6, the controller can automatically adjust the operating parameters of the vacuum pump 10 or prompt the operator to perform dehumidification, ensuring equipment lifespan and system vacuum stability, and indirectly reducing the risk of backflow caused by equipment failure.

[0025] The medium discharged by the vacuum pump 10 enters the exhaust gas treatment tank 12. After purification treatment in the tank, it is discharged in compliance with regulations through the exhaust gas discharge port 11. The drain valve 13 at the bottom of the exhaust gas treatment tank 12 can be opened periodically to drain the condensed water in the tank, avoiding excessive water accumulation that may affect the exhaust gas treatment efficiency or increase the risk of backflow due to water backflow. When the system needs to be shut down, the PLC controller 6 controls according to the preset sequence, first shutting down the Roots pump 7, and then shutting down the vacuum pump 10 after the system pressure stabilizes. At the same time, it controls the high vacuum solenoid valve 8 and all pneumatic valves 3 to close, cutting off all airflow channels. During the shutdown process, the sealing plate 53 of the one-way valve group 5 always remains in contact with the blocking ring 54 to prevent external media from being backflowed into the system, ensuring the sealing and safety of the system after shutdown.

[0026] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0027] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An anti-backflow structure for a high-vacuum solenoid valve, characterized in that, include: A condensing buffer tank (4) is provided with a pneumatic valve (3) connected to its outer wall via a conveying pipe. A vacuum transmitter (2) is connected to the outer wall of the pneumatic valve (3) on the side away from the condensing buffer tank (4) via a conveying pipe. A connecting pipe (15) is connected to the outer wall of the condensing buffer tank (4) away from the pneumatic valve (3). A one-way valve assembly (5) is fixedly connected to the inner wall of the connecting pipe (15). The one-way valve assembly (5) includes a connecting pipe (51), a blocking ring (54) is fixedly connected to the inner wall of the connecting pipe (51), a sealing plate (53) is attached to the outer wall of the blocking ring (54), a sleeve (55) is fixedly connected to the outer wall of the sealing plate (53) near the blocking ring (54), a tension spring (52) is fixedly connected inside the sleeve (55), a pressure relief pipe is connected through the outer wall below the connecting pipe (51), and a sealing plate (53) is also fixedly connected to the inner wall of the pressure relief pipe.

2. The anti-backflow structure of a high-vacuum solenoid valve according to claim 1, characterized in that: A Roots pump (7) is connected to the outer wall of the end of the connecting pipe (15) away from the condensation buffer tank (4). A high vacuum solenoid valve (8) is connected to the outlet of the Roots pump (7) through a conveying pipe. A vacuum pump (10) is connected to the outer wall of the high vacuum solenoid valve (8) away from the Roots pump (7) through a conveying pipe. A micro water detector (9) is fixedly connected to the outer wall of the vacuum pump (10). A tail gas treatment tank (12) is connected to the outlet of the vacuum pump (10) through a conveying pipe.

3. The anti-backflow structure of a high-vacuum solenoid valve according to claim 2, characterized in that: A vacuum detection transmitter (2) is also connected through the outer wall above the condensing buffer tank (4). A gas leak valve (16) is connected through the outer wall below the one-way valve group (5). A liquid level switch (17) is fixedly connected to the outer wall below the gas leak valve (16). A drain valve (18) is connected through the outer wall below the condensing buffer tank (4). The detection end of the vacuum detection transmitter (2) extends to the inner wall of the delivery pipe. A transformer vacuum pumping port (1) is provided on the outer wall of the vacuum detection transmitter (2) away from the pneumatic valve (3).

4. The anti-backflow structure of a high-vacuum solenoid valve according to claim 2, characterized in that: The outer wall of the condensing buffer tank (4) located below the transformer vacuum pumping port (1) is connected to a CLS vacuum pumping port (14). The CLS vacuum pumping port (14) and the condensing buffer tank (4) are connected through a conveying pipe. The inner wall of the through pipe between the CLS vacuum pumping port (14) and the condensing buffer tank (4) is also connected to a pneumatic valve (3). The detection end of the micro water detector (9) is located inside the vacuum pump (10). The outer wall of the condensing buffer tank (4) is fixedly connected to a PLC controller (6).

5. The anti-backflow structure of a high-vacuum solenoid valve according to claim 4, characterized in that: The exhaust gas treatment tank (12) has an exhaust gas outlet (11) connected to the outer wall above it. The exhaust gas treatment tank (12) has a drain valve (13) fixedly connected to the outer wall below it. The PLC controller (6) is connected to the vacuum detection transmitter (2), pneumatic valve (3), Roots pump (7), high vacuum solenoid valve (8), micro water detector (9), vacuum pump (10), gas leakage valve (16) and liquid level switch (17) through wires. The PLC controller (6) controls the start and stop of the entire equipment.

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