Pilot operated solenoid valve and agricultural plant protection unmanned aerial vehicle

Abstract

The utility model belongs to the technical field of electromagnetic valve, especially, a kind of pilot electromagnetic valve and agricultural plant protection unmanned plane are more particularly related to.The pilot electromagnetic valve includes valve body assembly, membrane pressing assembly, diaphragm and core assembly, the outer edge of diaphragm is set to the outer circumferential edge of diaphragm and is clamped and fixed by valve body assembly, and diaphragm, membrane pressing assembly and valve body assembly are jointly enclosed to form pilot chamber;The core assembly includes movable core, and movable core is set to the outside of pilot chamber;Diaphragm can be blocked pressure relief hole by sealing portion;When sealing portion blocks pressure relief hole, medium in pilot chamber can generate a pushing force towards membrane pressing assembly to sealing portion.This application's pilot electromagnetic valve can adopt larger aperture's pressure relief hole, to meet the use demand of agricultural plant protection unmanned plane;In addition, core assembly will not contact with medium in pilot chamber, prevent the medium in pilot chamber from affecting the normal work of core assembly.

Description

Technical Field

[0001] This application belongs to the field of electromagnetic valve technology, and in particular relates to a pilot-operated electromagnetic valve and an agricultural plant protection drone. Background Technology

[0002] With the widespread application of drone technology in agricultural plant protection, pesticide spraying technology using agricultural plant protection drones has become an important means of achieving precision agriculture. This technology significantly improves pesticide utilization through precise spraying, effectively reduces pesticide residues and runoff in the environment, and achieves the goal of reducing pesticide application, thus helping to reduce pollution of soil and water sources. To further improve the spraying efficiency of agricultural plant protection drones and solve the problem of limited coverage area, solenoid valves, which combine high flow rate and rapid, precise control capabilities, have become a key component. Pilot-operated solenoid valves, with their ability to control the opening and closing of the pilot port with relatively small electromagnetic force and to use the pressure difference of the medium itself to drive the movement of the main valve diaphragm to achieve rapid opening and closing of the main valve port, are widely used in agricultural plant protection drones to meet their needs for efficient and precise agricultural spraying operations.

[0003] In existing pilot-operated solenoid valve designs, the sealing force required for the valve stem to drive the plug and seal the pilot port is primarily provided by the spring force. Due to the structural characteristics of pilot-operated solenoid valves, the spring force is typically designed to be relatively small. To achieve a reliable seal with a smaller spring force, the diameter of the pilot port needs to be correspondingly reduced to decrease the required sealing area. However, in actual pesticide spraying applications, pesticide fluids often exhibit crystallization, and these crystal particles easily clog the pilot port. Once the pilot port is clogged, the pilot pressure cannot be established normally, ultimately preventing the main valve from opening and closing properly. This causes the pilot-operated solenoid valve to malfunction, severely impacting the normal operation of agricultural drones. Utility Model Content

[0004] In view of this, it is necessary to provide a pilot-operated solenoid valve and an agricultural plant protection drone that can solve the above-mentioned technical problems.

[0005] A pilot-operated solenoid valve, comprising:

[0006] The valve body assembly has an inlet channel, a valve port, and an outlet channel, wherein the inlet channel and the outlet channel are connected through the valve port;

[0007] A pressure-film assembly is installed on the valve body assembly. The pressure-film assembly has an inlet port and a pressure relief port. The inlet port is connected to the inlet channel, and the pressure relief port is connected to the outlet channel.

[0008] A diaphragm sheet includes an outer edge portion, which is disposed on the outer periphery of the diaphragm sheet and clamped and fixed by the valve body assembly. The diaphragm sheet, the pressure membrane assembly, and the valve body assembly together enclose a pilot chamber, which is respectively connected to the liquid inlet and the pressure relief hole.

[0009] The core assembly includes a movable core, which is disposed outside the pilot chamber and is connected to the diaphragm plate for driving the diaphragm plate to open / close the pressure relief hole;

[0010] The diaphragm further includes a sealing portion, and the diaphragm can block the pressure relief hole through the sealing portion; and when the sealing portion blocks the pressure relief hole, the medium in the pilot chamber can generate a pushing force on the sealing portion toward the pressure membrane assembly.

[0011] Understandably, the medium in the pilot chamber can exert a pushing force on the sealing part towards the pressure diaphragm assembly, so that when the diaphragm blocks the pressure relief hole through the sealing part, the medium in the pilot chamber can assist the sealing part in blocking the pressure relief hole, enhancing the sealing effect of the sealing part on the pressure relief hole. This allows the pilot-operated solenoid valve to use a larger diameter pressure relief hole to meet the needs of agricultural plant protection drones. At the same time, the valve body assembly clamps and fixes the outer edge of the diaphragm and places the iron core assembly outside the pilot chamber, avoiding contact between the iron core assembly and the medium in the pilot chamber, and preventing the medium in the pilot chamber from affecting the normal operation of the iron core assembly.

[0012] In one embodiment, the sealing portion includes a first sealing portion and a second sealing portion, the second sealing portion being disposed around the periphery of the first sealing portion and connected to the first sealing portion; wherein, the first sealing portion is drivenly connected to the movable iron core, and the medium in the pilot chamber can generate the pushing force on the second sealing portion;

[0013] When the sealing part blocks the pressure relief hole, the first sealing part and the second sealing part simultaneously press against and limit the pressure membrane assembly.

[0014] In one embodiment, the pressure membrane assembly is provided with a rib, which is disposed around the pressure relief hole;

[0015] When the sealing part blocks the pressure relief hole, the sealing part can undergo elastic deformation under the pushing of the rib.

[0016] Understandably, the ribs on the pressure membrane assembly push the sealing part and cause it to undergo elastic deformation, so that the sealing part can fit tightly with the ribs of the pressure membrane assembly to ensure the sealing reliability when the sealing part blocks the pressure relief hole.

[0017] In one embodiment, the diameter of the pressure relief hole is set to D, where D ≥ 2 mm.

[0018] In one embodiment, the pilot-operated solenoid valve further includes a connecting rod, through which the movable iron core is connected to the sealing part.

[0019] In one embodiment, one end of the connecting rod is threaded to the movable iron core, and the other end of the connecting rod is snapped to the sealing part.

[0020] Understandably, the connecting rod is connected to the movable iron core by a thread, which facilitates the assembly of the connecting rod on the movable iron core.

[0021] In one embodiment, the pilot-operated solenoid valve further includes a magnetic shielding tube;

[0022] The valve body assembly includes a valve body, a first base plate, and a second base plate. The first base plate is connected to the valve body, and the connected first base plate and the valve body can clamp and fix the outer periphery of the pressure film assembly. The second base plate is partially pressed and limited by the first base plate and the magnetic shielding tube, and the second base plate and the first base plate can clamp and fix the outer edge.

[0023] The inlet channel, the valve port, and the outlet channel are all located on the valve body.

[0024] It is understandable that the outer periphery of the pressure membrane assembly is clamped and fixed by the first base plate and the valve body, and the outer edge of the diaphragm is clamped and fixed by the second base plate and the first base plate. This ensures the sealing between the pressure membrane assembly and the first base plate and the valve body, as well as between the outer edge of the diaphragm and the second base plate and the first base plate.

[0025] In one embodiment, the second base plate includes a first plate portion and a second plate portion, wherein the second plate portion and the first plate portion are disposed at an angle.

[0026] One end of the first plate portion away from the second plate portion is pressed and limited by the first base plate and the magnetic shielding tube. The second plate portion is provided with a slot, which is provided to receive the outer edge portion. Furthermore, the second plate portion can clamp and fix the outer edge portion with the first base plate.

[0027] The end of the second plate portion that is away from the first plate portion abuts and limits the contact with a portion of the diaphragm sheet.

[0028] In one embodiment, a limiting rib is provided on the first base plate. The limiting rib can abut against the pressure film assembly to limit the movement stroke of the pressure film assembly when it opens the valve port.

[0029] This application also seeks protection for an agricultural plant protection drone, including the aforementioned pilot-operated solenoid valve.

[0030] Due to the application of the above solution, this application has the following advantages compared with the prior art:

[0031] The pilot-operated solenoid valve and agricultural plant protection drone claimed in this application have a pilot chamber in which the medium can exert a pushing force on the sealing part toward the pressure diaphragm assembly. This allows the medium in the pilot chamber to assist the sealing part in sealing the pressure relief hole when the diaphragm blocks it through the sealing part, thereby enhancing the sealing effect of the sealing part on the pressure relief hole. This allows the pilot-operated solenoid valve to use a larger diameter pressure relief hole to meet the usage requirements of agricultural plant protection drones. At the same time, the valve body assembly clamps and fixes the outer edge of the diaphragm and places the iron core assembly outside the pilot chamber, preventing the iron core assembly from contacting the medium in the pilot chamber and preventing the medium in the pilot chamber from affecting the normal operation of the iron core assembly. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the structure of a pilot-operated solenoid valve provided in an embodiment of this application.

[0034] Figure 2 This is a schematic diagram of the pilot-operated solenoid valve provided in one embodiment of this application from another perspective.

[0035] Figure 3 for Figure 2 Sectional view at point AA.

[0036] Figure 4 This is a schematic diagram of the structure of the pressure membrane assembly and diaphragm sheet provided in an embodiment of this application.

[0037] Figure 5 This is a schematic diagram of the structure of the first base plate provided in an embodiment of this application.

[0038] Reference numerals: 100, Pilot-operated solenoid valve; 101, Pilot chamber; 11, Inlet channel; 12, Valve port; 13, Outlet channel; 14, Valve body; 15, First base plate; 151, Limiting rib; 16, Second base plate; 161, First plate section; 162, Second plate section; 1621, Groove; 20, Diaphragm assembly; 21, Inlet hole; 22, Pressure relief hole; 23, Outer periphery; 24, Rib; 25, Pilot diaphragm; 26, Pressure plate; 30, Diaphragm; 31, Outer edge; 32, Sealing part; 321, First sealing section; 322, Second sealing section; 40, Core assembly; 41, Movable core; 42, Spring; 43, Fixed core; 50, Magnetic shielding tube; 60, Screw; 70, Nut; 80, Connecting rod; 81, Annular groove. Detailed Implementation

[0039] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0040] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or there may be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application's specification are for illustrative purposes only and do not represent the only possible implementation.

[0041] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0042] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0043] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used in this application includes any and all combinations of one or more of the associated listed items.

[0044] The pilot-operated solenoid valve 100 claimed in this application is used in agricultural plant protection drones (not shown) to control the flow of pesticide fluid.

[0045] like Figures 1 to 5 As shown, the pilot-operated solenoid valve 100 claimed in this application includes a valve body assembly, a diaphragm assembly 20, a diaphragm 30, and an iron core assembly 40. The valve body assembly has an inlet channel 11, a valve port 12, and an outlet channel 13, with the inlet channel 11 and the outlet channel 13 connected via the valve port 12. The diaphragm assembly 20 is mounted on the valve body assembly and has an inlet hole 21 and a pressure relief hole 22. The inlet hole 21 is connected to the inlet channel 11, and the pressure relief hole 22 is connected to the outlet channel 13. The diaphragm 30 includes an outer edge 31, which is disposed on the outer periphery of the diaphragm 30 and clamped and fixed by the valve body assembly. The pressure-mesh assembly 20 and the valve body assembly together form a pilot chamber 101, which is connected to the inlet port 21 and the pressure relief port 22. The core assembly 40 includes a movable core 41, which is disposed outside the pilot chamber 101 and is drivenly connected to the diaphragm 30 to drive the diaphragm 30 to open / close the pressure relief port 22. The diaphragm 30 also includes a sealing part 32, which can block the pressure relief port 22. When the sealing part 32 blocks the pressure relief port 22, the medium in the pilot chamber 101 can exert a pushing force on the sealing part 32 towards the pressure-mesh assembly 20. Here, the medium can be pesticide or other liquid.

[0046] As can be seen from the above, in the pilot-operated solenoid valve 100 of this application, the medium in the pilot chamber 101 can exert a pushing force on the sealing part 32 toward the pressure diaphragm assembly 20, so that when the diaphragm 30 blocks the pressure relief hole 22 through the sealing part 32, the medium in the pilot chamber 101 can assist the sealing part 32 in blocking the pressure relief hole 22, thereby enhancing the sealing effect of the sealing part 32 on the pressure relief hole 22. This allows the pilot-operated solenoid valve 100 to use a larger diameter pressure relief hole 22 to meet the needs of agricultural plant protection drones. At the same time, the outer edge 31 of the diaphragm 30 is clamped and fixed by the valve body assembly, and the iron core assembly 40 is set outside the pilot chamber 101. In this way, the iron core assembly 40 is prevented from contacting the medium in the pilot chamber 101, and the medium in the pilot chamber 101 is prevented from affecting the normal operation of the iron core assembly 40.

[0047] like Figure 2 As shown, in one embodiment, the core assembly 40 includes a spring 42 and a fixed core 43. The spring 42 is pre-compressed and positioned between the fixed core 43 and the movable core 41. Under the push of the spring 42, the movable core 41 drives the sealing portion 32 of the diaphragm 30 to block the pressure relief hole 22. That is, when the pilot-operated solenoid valve 100 of this application is not activated, the spring 42 and the medium in the pilot chamber 101 can work together to act on the sealing portion 32 to drive the sealing portion 32 to block the pressure relief hole 22.

[0048] like Figure 2 , Figure 3 As shown, in one embodiment, the sealing part 32 includes a first sealing portion 321 and a second sealing portion 322. The second sealing portion 322 is disposed around the first sealing portion 321 and connected to the first sealing portion 321. The first sealing portion 321 is connected to the movable iron core 41, and the medium in the pilot chamber 101 can generate a pushing force on the second sealing portion 322. When the sealing part 32 blocks the pressure relief hole 22, the first sealing portion 321 and the second sealing portion 322 simultaneously press against and limit the pressure membrane assembly 20.

[0049] like Figure 2 As shown, in one embodiment, the diameter of the pressure relief hole 22 is set to D, where D ≥ 2 mm. The diameter of the pressure relief hole 22 in this embodiment is designed to be 2 mm, which meets the actual usage requirements of the pilot-operated solenoid valve 100 equipped with a large-diameter pressure relief hole 22. It is understood that in other embodiments, the diameter of the pressure relief hole 22 may also be 2.5 mm or 3 mm, which will not be elaborated upon here.

[0050] like Figure 2As shown, in one embodiment, the pilot-operated solenoid valve 100 further includes a magnetic shielding tube 50; the valve body assembly includes a valve body 14, a first base plate 15, and a second base plate 16. The first base plate 15 is connected to the valve body 14, and the connected first base plate 15 and valve body 14 can clamp and fix the outer periphery 23 of the pressure film assembly 20; the second base plate 16 is partially pressed and limited by the first base plate 15 and the magnetic shielding tube 50, and the second base plate 16 and first base plate 15 can clamp and fix the outer edge 31; the liquid inlet channel 11, the valve port 12, and the liquid outlet channel 13 are all provided on the valve body 14. In other words, in this embodiment, the outer periphery 23 of the pressure membrane assembly 20 is clamped and fixed by the first base plate 15 and the valve body 14, and the outer edge 31 of the diaphragm sheet 30 is clamped and fixed by the second base plate 16 and the first base plate 15, thereby ensuring the sealing between the pressure membrane assembly 20 and the first base plate 15 and the valve body 14, and between the outer edge 31 of the diaphragm sheet 30 and the second base plate 16 and the first base plate 15. Here, the connection between the magnetic shielding tube 50 and the first base plate 15 is specifically achieved by screwing the first base plate 15 with the screw 60 passing through the magnetic shielding tube 50; the connection and fixation between the first base plate 15 and the valve body 14 is achieved by pressing the first base plate 15 onto the valve body 14 with the nut 70, while the nut 70 is screwed onto the threaded structure on the valve body 14.

[0051] like Figure 2 As shown, in one embodiment, the second base plate 16 includes a first plate portion 161 and a second plate portion 162, which are arranged at an angle to the first plate portion 161. The end of the first plate portion 161 away from the second plate portion 162 is pressed and limited by the first base plate 15 and the magnetic shielding tube 50. The second plate portion 162 is provided with a slot 1621, which accommodates the outer edge portion 31 of the portion. The second plate portion 162 can clamp and fix the outer edge portion 31 with the first base plate 15. The end of the second plate portion 162 away from the first plate portion 161 is partially abutted and limited by the diaphragm sheet 30. In other words, the end of the second plate portion 162 away from the first plate portion 161 in this embodiment can provide partial support for the diaphragm 30, so that when the diaphragm 30 blocks the pressure relief hole 22 through the sealing portion 32, the pushing force exerted by the medium in the pilot chamber 101 on the diaphragm 30 towards the magnetic shielding tube 50 will be balanced by the second plate portion 162, thereby helping the sealing portion 32 to more reliably block the pressure relief hole 22.

[0052] like Figure 2 , Figure 5As shown, in one embodiment, a limiting rib 151 is provided on the first base plate 15. The limiting rib 151 can abut against the pressure membrane assembly 20 to limit the movement stroke of the pressure membrane assembly 20 when it opens the valve port 12. The pressure membrane assembly 20 includes a pilot diaphragm 25 and a pressure plate 26. The pressure plate 26 partially passes through the pilot diaphragm 25 and abuts against the pilot diaphragm 25 for limitation. In addition, a pressure relief hole 22 is provided through the pressure plate 26. In other words, when the pilot-operated solenoid valve 100 of this embodiment is working, the medium in the pilot chamber 101 is depressurized to the outlet channel 13 through the pressure relief hole 22, resulting in a decrease in the internal pressure of the pilot chamber 101. Under the action of the medium pressure difference, the pressure diaphragm assembly 20 moves toward the first base plate 15. At this time, the limiting ribs 151 on the first base plate 15 abut against the pressure plate 26 of the pressure diaphragm assembly 20, thereby limiting the deformation of the pilot diaphragm 25 during the movement of the pressure diaphragm assembly 20, preventing excessive deformation of the pilot diaphragm 25, and playing a role in protecting the pilot diaphragm 25. Here, there are four limiting ribs 151, which are arranged at intervals along the circumferential direction of the sealing part 32 on the first base plate 15.

[0053] like Figure 2 , Figure 3 As shown, in one embodiment, the pressure-membrane assembly 20 is provided with a raised rib 24, which is disposed around the pressure relief hole 22. When the sealing part 32 blocks the pressure relief hole 22, the sealing part 32 can undergo elastic deformation under the pushing of the raised rib 24. That is, in this embodiment, the sealing part 32 undergoes elastic deformation under the pushing of the raised rib 24 of the pressure-membrane assembly 20, so that the sealing part 32 can fit tightly with the raised rib 24 of the pressure-membrane assembly 20, thereby ensuring the sealing reliability of the sealing part 32 when blocking the pressure relief hole 22.

[0054] like Figure 2 As shown, in one embodiment, the pilot-operated solenoid valve 100 further includes a connecting rod 80, and the movable iron core 41 is connected to the sealing part 32 through the connecting rod 80.

[0055] like Figure 2 As shown, in one embodiment, one end of the connecting rod 80 is threaded to the movable iron core 41, and the other end of the connecting rod 80 is snap-fitted to the sealing part 32. That is, in this embodiment, the connecting rod 80 and the movable iron core 41 are connected by a thread, which facilitates the assembly and connection of the connecting rod 80 onto the movable iron core 41. In other embodiments, the connecting rod 80 and the movable iron core 41 can also be connected by a snap-fit, which will not be elaborated upon here.

[0056] In this embodiment, the connecting rod 80 and the sealing part 32 are connected by a snap-fit ​​method, which facilitates the assembly of the sealing part 32 on the connecting rod 80. Specifically, an annular groove 81 can be provided on the connecting rod 80, and the sealing part 32 can be snap-fitted into the annular groove 81.

[0057] When the pilot-operated solenoid valve 100 of this application is de-energized, the medium in the inlet channel 11 enters the pilot chamber 101 through the inlet hole 21 on the pressure diaphragm assembly 20. The medium pressure above the pressure diaphragm assembly 20 is greater than the pressure below the pressure diaphragm assembly 20. Under the action of the medium pressure difference, the pressure diaphragm assembly 20 moves downward and seals the valve port 12. When the pilot-operated solenoid valve 100 is energized, the movable iron core 41 compresses the spring 42 under the action of electromagnetic force and moves toward the fixed iron core 43. During this process, the movable iron core 41 drives the sealing part 32 away from the pressure relief hole 22 through the connecting rod 80, thereby opening the pressure relief hole 22. At this time, the medium in the pilot chamber 101 is depressurized to the outlet channel 13 through the pressure relief hole 22, resulting in a decrease in the internal pressure of the pilot chamber 101. Under the action of the medium pressure difference, the pressure diaphragm assembly 20 moves toward the magnetic shielding tube 50, thereby opening the valve port 12.

[0058] This application also seeks protection for an agricultural plant protection drone, including the aforementioned pilot-operated solenoid valve 100.

[0059] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0060] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the patent protection scope of this application should be determined by the appended claims.

Claims

1. A pilot-operated solenoid valve, characterized in that, The pilot-operated solenoid valve (100) includes: The valve body assembly has an inlet channel (11), a valve port (12) and an outlet channel (13), wherein the inlet channel (11) and the outlet channel (13) are connected through the valve port (12); A pressure membrane assembly (20) is installed on the valve body assembly. The pressure membrane assembly (20) has an inlet hole (21) and a pressure relief hole (22). The inlet hole (21) is connected to the inlet channel (11), and the pressure relief hole (22) is connected to the outlet channel (13). The diaphragm (30) includes an outer edge (31), which is disposed on the outer periphery of the diaphragm (30) and is clamped and fixed by the valve body assembly. The diaphragm (30), the pressure membrane assembly (20) and the valve body assembly together form a pilot chamber (101), which is connected to the liquid inlet (21) and the pressure relief hole (22) respectively. The core assembly (40) includes a movable core (41), which is disposed on the outside of the pilot chamber (101) and is connected to the diaphragm (30) for driving the diaphragm (30) to open / close the pressure relief hole (22). The diaphragm (30) further includes a sealing part (32), and the diaphragm (30) can block the pressure relief hole (22) through the sealing part (32); and when the sealing part (32) blocks the pressure relief hole (22), the medium in the pilot chamber (101) can generate a pushing force on the sealing part (32) towards the pressure membrane assembly (20).

2. The pilot-operated solenoid valve according to claim 1, characterized in that, The sealing part (32) includes a first sealing part (321) and a second sealing part (322). The second sealing part (322) is disposed around the first sealing part (321) and connected to the first sealing part (321). The first sealing part (321) is connected to the movable iron core (41) in a driving connection. The medium in the pilot chamber (101) can generate the pushing force on the second sealing part (322). When the sealing part (32) blocks the pressure relief hole (22), the first sealing part (321) and the second sealing part (322) simultaneously press against and limit the pressure membrane assembly (20).

3. The pilot-operated solenoid valve according to claim 1, characterized in that, The pressure membrane assembly (20) is provided with a rib (24), which is located around the pressure relief hole (22); When the sealing part (32) blocks the pressure relief hole (22), the sealing part (32) can undergo elastic deformation under the pushing of the rib (24).

4. The pilot-operated solenoid valve according to claim 1, characterized in that, The diameter of the pressure relief hole (22) is set to D, where D≥2mm.

5. The pilot-operated solenoid valve according to claim 1, characterized in that, The pilot-operated solenoid valve (100) also includes a connecting rod (80), and the movable iron core (41) is connected to the sealing part (32) through the connecting rod (80).

6. The pilot-operated solenoid valve according to claim 5, characterized in that, One end of the connecting rod (80) is threaded to the movable iron core (41), and the other end of the connecting rod (80) is snapped to the sealing part (32).

7. The pilot-operated solenoid valve according to claim 1, characterized in that, The pilot-operated solenoid valve (100) also includes a magnetic shielding tube (50). The valve body assembly includes a valve body (14), a first base plate (15), and a second base plate (16). The first base plate (15) is connected to the valve body (14), and the connected first base plate (15) and the valve body (14) can clamp and fix the outer periphery (23) of the pressure film assembly (20). The second base plate (16) is partially pressed and limited by the first base plate (15) and the magnetic shielding tube (50), and the second base plate (16) and the first base plate (15) can clamp and fix the outer edge (31). The inlet channel (11), the valve port (12), and the outlet channel (13) are all located on the valve body (14).

8. The pilot-operated solenoid valve according to claim 7, characterized in that, The second base plate (16) includes a first plate portion (161) and a second plate portion (162), and the second plate portion (162) and the first plate portion (161) are arranged at an angle; One end of the first plate portion (161) away from the second plate portion (162) is pressed and limited by the first base plate (15) and the magnetic shielding tube (50). The second plate portion (162) is provided with a slot (1621), which accommodates part of the outer edge portion (31). Furthermore, the second plate portion (162) can clamp and fix the outer edge portion (31) with the first base plate (15). The end of the second plate (162) away from the first plate (161) abuts against and limits the portion of the diaphragm (30).

9. The pilot-operated solenoid valve according to claim 7, characterized in that, The first base plate (15) is provided with a limiting rib (151), which can abut against the pressure film assembly (20) to limit the movement stroke of the pressure film assembly (20) when it opens the valve port (12).

10. An agricultural plant protection drone, characterized in that, Includes the pilot-operated solenoid valve (100) as described in any one of claims 1 to 9.

Images