An air circulation system for a greenhouse and a sterilization process
By designing a plasma exciter, a flow guide tube, and an airflow regulation component into the greenhouse air circulation system, the problem of insufficient contact between the plasma and the contaminated area and the inner wall was solved, achieving uniform disinfection and efficient sterilization, preventing microbial adhesion, and improving the sterilization effect and energy utilization efficiency of the system.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHANGHAI HUAZE ENVIRONMENTAL TECH CO LTD
- Filing Date
- 2025-07-31
- Publication Date
- 2026-07-07
AI Technical Summary
In existing greenhouse air circulation systems, plasma may pass through contaminated areas quickly but fail to completely eliminate pathogens. Furthermore, the high airflow speed makes it difficult for plasma to make sufficient contact with the inner wall of the drainage tube, causing microorganisms to form biofilms on the inner wall and continuously release live bacteria, resulting in secondary pollution of the system.
An air circulation system was designed, including a plasma exciter, a drainage tube, an auxiliary tube, a rotating tube, blades, and an airflow regulation component. By controlling the airflow speed and plasma diffusion intensity, the plasma is ensured to make full contact with the inner wall of the drainage tube, and a negative pressure vacuum cleaner is used to remove dust and prevent microbial adhesion.
It effectively improves the efficiency of plasma treatment of contaminated areas, avoids treatment dead spots, ensures uniform disinfection of every part of the inner wall, prevents microbial residue, and improves the sterilization effect and energy utilization efficiency of the system.
Smart Images
Figure CN120959080B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of air circulation technology, specifically to an air circulation system and sterilization process for greenhouses. Background Technology
[0002] The monoculture of crops within greenhouses often leads to severe continuous cropping, resulting in the proliferation of pathogens. However, existing greenhouse environmental control capabilities are weak, with limited functions for regulating the environment. These systems often rely on high-energy consumption to control diseases, leading to high carbon emissions and costs. A greenhouse air circulation system is a device that uses mechanical or natural methods to force or guide airflow to optimize the internal environment (temperature, humidity, CO2 concentration, air quality, etc.) of the greenhouse. Its core function is to eliminate local microclimate differences, promote uniform crop growth, reduce pests and diseases, and improve energy efficiency.
[0003] During the operation of the circulation system, the generated airflow can quickly drive the airflow, allowing the plasma to uniformly cover the entire space. If the airflow speed is fast, although it can accelerate the contact frequency between pathogens and disinfectants, the plasma may quickly pass through the contaminated area, which is not conducive to the complete elimination of pathogens. Furthermore, due to the fast airflow speed, the plasma does not easily come into contact with the inner wall of the drainage tube. The inner wall of the drainage tube is in long-term contact with microorganisms in the airflow, and pathogens (such as molds and staphylococci) will form biofilms on the surface. These biofilms are not only difficult to be killed by subsequent disinfection, but they will also continuously release live bacteria into the airflow, leading to secondary pollution of the system.
[0004] To address the aforementioned issues, innovative designs are urgently needed based on existing approaches. Summary of the Invention
[0005] The purpose of this invention is to provide an air circulation system and sterilization process for greenhouses, which solves the problems mentioned in the background technology, such as plasma passing through the contaminated area too quickly, which is not conducive to the complete elimination of pathogens. Furthermore, due to the high airflow speed, the plasma does not easily come into contact with the inner wall of the drainage tube. The inner wall of the drainage tube is in long-term contact with microorganisms in the airflow, which are difficult to be subsequently disinfected and killed. This invention provides a solution that is significantly different from the prior art.
[0006] To achieve the above objectives, the present invention provides the following technical solution: an air circulation system and sterilization process for greenhouses, comprising a plasma exciter and a drainage cylinder, wherein an auxiliary cylinder is installed at the end of the drainage cylinder away from the plasma exciter, a rotating cylinder is installed inside the plasma exciter via a motor, a paddle is provided inside the rotating cylinder, a rotating ring is rotatably connected inside the auxiliary cylinder, an installation platform is installed on the outer surface of the auxiliary cylinder, a diffusion platform is installed inside the auxiliary cylinder, an airflow regulating component is provided on the outer surface of the auxiliary cylinder, a negative pressure vacuum cleaner is installed on the inner wall of the drainage cylinder in the area to the right of the rotating cylinder, a turntable is installed at the left end inside the drainage cylinder, a sleeve is fitted on the surface of the turntable, and a cleaning and adjusting component is provided on the surface of the turntable;
[0007] The airflow regulating assembly includes a connecting ring installed outside the rotating ring, a swing block rotatably connected inside the connecting ring, an abutment block slidingly limited inside the mounting platform, an abutment frame slidingly limited inside the mounting platform, a fan rotatably connected inside the diffuser platform, a rotating ring rotatably connected inside the diffuser platform, and a drive ring rotatably connected inside the auxiliary cylinder.
[0008] Preferably, a slide rod is installed at one end of the blade near the rotating drum. The slide rod slides within the rotating drum and is limited by a spring. A protrusion is installed at one end of the slide rod near the inside of the rotating drum.
[0009] Preferably, the rotating ring is equipped with three sets of spiral baffles, which are evenly distributed in a circular shape inside the rotating ring.
[0010] Preferably, both the diffuser platform and the rotating end are provided with a 45° inclined surface, and the diffuser platform and the inclined surface of the rotating ring are provided with a plurality of ventilation holes. The inclined surface of the rotating end is in close contact with the inclined surface inside the diffuser platform. The surface of the diffuser platform is provided with a groove, and the drive ring passes through the groove and is connected to the rotating ring.
[0011] Preferably, the connecting ring is connected to the swing block by a torsion spring, and there are three sets of swing blocks. The three sets of swing blocks are evenly distributed in a circular shape inside the connecting ring, and the swing block is provided with an inclined surface on the side close to the connecting ring.
[0012] Preferably, a thin rod is installed near one end of the contact frame close to the contact block. The surface of the thin rod slides within the mounting platform, and one end of the thin rod is connected to the contact block. A spring is installed on the side of the contact block, and the other end of the spring is connected to the inner wall of the mounting platform.
[0013] Preferably, an adjusting ring is installed at the other end of the contact frame, the surface of the adjusting ring is provided with an inclined groove, the external protrusion of the drive ring slides within the inclined groove on the surface of the adjusting ring, and the end of the connecting ring away from the diversion tube is connected to the fan.
[0014] Preferably, the cleaning and adjustment assembly includes blades rotatably connected to the surface of the turntable, a toothed ring is installed on the surface of the rotating rod at the end of the blade, a first electric push rod is installed at one end of the turntable near the inside of the drainage tube, the extended end of the first electric push rod is connected to the inner wall of the sleeve, a rack is installed in the notch inside the sleeve, a second electric push rod is installed at the bottom of the negative pressure vacuum cleaner, and an abutment is installed at the extended end of the second electric push rod.
[0015] Preferably, the rack meshes with the gear ring, the contact platform is a half-frustum shape, and the contact platform is located inside the rotating cylinder.
[0016] Preferably, the method includes the following steps:
[0017] S1: The plasma exciter emits plasma into the drainage tube. The bidirectional motor drives the rotating drum and the sleeve to rotate. The rotation of the sleeve drives the turntable to rotate, so that the plasma comes into full contact with the inner wall of the drainage tube and sterilizes the inside of the drainage tube. The rotation of the rotating drum drives the paddle to rotate, so that the air carrying the plasma is discharged through the auxiliary tube and sterilizes the external environment.
[0018] S2: When the rotating drum rotates at a high speed, the plasma is discharged before it comes into contact with the inner wall. The controller drives the cleaning and adjustment components to operate, increasing the diffusion force of the plasma so that it can fully contact the inner wall of the drainage tube to achieve the sterilization effect.
[0019] S3: When the rotating drum rotates at a high speed, the gas flow rate inside the drainage tube is also high. By using the airflow regulating component to slow down the gas flow rate inside the auxiliary tube, the outward diffusion range is increased, which can fully sterilize the external environment.
[0020] Compared with the prior art, the beneficial effects of the present invention are:
[0021] 1. This invention, through the design of an auxiliary cylinder, rotating ring, mounting platform, and diffusion platform, allows the airflow inside the guide cylinder to diffuse outwards, slowing down the airflow velocity. This enables the plasma to more widely permeate the contaminated area, rather than being confined to the narrow space near the guide cylinder. For large contaminated areas, it ensures uniform plasma distribution, improves the efficiency of pollutant treatment, avoids treatment dead zones, and, when the airflow velocity inside the guide cylinder is high, reduces the diameter of the diffusion platform's vent and increases its pressure. This allows the equipment to automatically adjust according to changes in the airflow velocity inside the guide cylinder, preventing uneven plasma diffusion or insufficient application to the contaminated area due to excessively fast airflow.
[0022] 2. This invention, through the designed turntable and sleeve, ensures that the plasma fully contacts the inner wall of the drainage tube, removing microorganisms from the airflow that has been in contact with the inner wall for a long time. Furthermore, when the gas flow rate inside the drainage tube is high, the cleaning and adjustment component changes the angle of the blades, expanding the plasma dispersion range and ensuring it remains in contact with the inner wall. This allows the plasma to adjust its distribution in a timely manner according to changes in the airflow, maintaining constant contact with the inner wall. Even under high-speed airflow impact, it ensures that every part of the inner wall is continuously affected by the plasma, effectively preventing microorganisms from remaining or re-attaching due to insufficient plasma coverage in high-speed airflow environments.
[0023] 3. This invention, through the combination of a contact platform and a negative pressure vacuum cleaner, can remove dust adhering to the blades. The contact platform acts directly on the blade surface through physical contact, causing firmly attached dust to fall off. The negative pressure vacuum cleaner utilizes the principle of negative pressure to generate strong suction, quickly sucking away the scraped dust and preventing it from re-adhering or being stirred up. Furthermore, when the air flow rate inside the drainage tube is relatively fast, this will increase the amount of dust accumulated on the blade surface. By simultaneously increasing the vibration of the blades, the dust on the blades can be removed in a timely and effective manner, ensuring efficient dust removal. Attached Figure Description
[0024] Figure 1 This is a schematic diagram of the main structure of the present invention;
[0025] Figure 2 This is a partial structural schematic diagram of the drainage tube and auxiliary tube of the present invention;
[0026] Figure 3 This is a schematic cross-sectional view of the drainage tube and auxiliary tube of the present invention;
[0027] Figure 4 This is a schematic diagram of the exploded structure of the auxiliary cylinder of the present invention;
[0028] Figure 5 This is a schematic diagram of the rotating ring structure of the present invention;
[0029] Figure 6 This is a schematic diagram of the airflow regulating component of the present invention;
[0030] Figure 7 This is a cross-sectional structural diagram of the airflow regulating component of the present invention;
[0031] Figure 8 For the present invention Figure 7 Enlarged structural diagram at point A in the middle;
[0032] Figure 9 This is a schematic diagram of the cleaning and adjustment component of the present invention;
[0033] Figure 10 For the present invention Figure 9 Enlarged structural diagram at point B;
[0034] Figure 11 This is a schematic cross-sectional view of the rotating cylinder of the present invention.
[0035] In the diagram: 1. Plasma exciter; 2. Drainage tube; 3. Auxiliary tube; 4. Rotating tube; 5. Paddle; 6. Rotating ring; 7. Mounting platform; 8. Diffuser platform; 901. Connecting ring; 902. Throwing block; 903. Contact block; 904. Contact frame; 905. Adjusting ring; 906. Fan; 907. Rotating ring; 908. Drive ring; 10. Negative pressure vacuum cleaner; 11. Turntable; 12. Sleeve; 131. Blade; 132. Gear ring; 133. First electric push rod; 134. Rack; 135. Second electric push rod; 136. Contact platform. Detailed Implementation
[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example
[0037] Please see Figures 1-11 This invention provides a technical solution: an air circulation system and sterilization process for greenhouses, including a plasma exciter 1 and a drainage cylinder 2. An auxiliary cylinder 3 is installed at the end of the drainage cylinder 2 away from the plasma exciter 1. A rotating cylinder 4 is installed inside the plasma exciter 1 via a motor. A paddle 5 is installed inside the rotating cylinder 4. A rotating ring 6 is rotatably connected inside the auxiliary cylinder 3. An installation platform 7 is installed on the outer surface of the auxiliary cylinder 3. A diffuser platform 8 is installed inside the auxiliary cylinder 3. An airflow regulating component is provided on the outer surface of the auxiliary cylinder 3. A negative pressure vacuum cleaner 10 is installed on the inner wall of the drainage cylinder 2 in the area to the right of the rotating cylinder 4. A turntable 11 is installed at the left end inside the drainage cylinder 2. A sleeve 12 is fitted on the surface of the turntable 11. A cleaning and regulating component is provided on the surface of the turntable 11.
[0038] The airflow regulating component includes a connecting ring 901 installed outside the rotating ring 6, a swing block 902 rotatably connected inside the connecting ring 901, a limiting sliding contact block 903 inside the mounting platform 7, a limiting sliding contact frame 904 inside the mounting platform 7, a fan 906 rotatably connected inside the diffuser platform 8, a rotating ring 907 rotatably connected inside the diffuser platform 8, and a drive ring 908 rotatably connected inside the auxiliary cylinder 3. The airflow regulating component can reduce the diameter of the vent hole of the diffuser platform 8 and increase its air pressure when the airflow velocity inside the diversion cylinder 2 is relatively fast, so that the equipment can automatically adjust according to the change in the airflow velocity inside the diversion cylinder 2.
[0039] In one embodiment of the present invention, a slide rod is installed at one end of the blade 5 near the rotating drum 4. The slide rod slides within the rotating drum 4 and is fitted with a spring. A protrusion is installed at one end of the slide rod near the inside of the rotating drum 4. When the protrusion contacts the contact platform 136, it causes the blade 5 to swing vertically within the rotating drum 4. The contact platform 136 acts directly on the surface of the blade 5 through physical contact, causing the firmly attached dust to fall off.
[0040] As one embodiment of the present invention, a spiral baffle is installed inside the rotating ring 6. There are three sets of baffles, which are evenly distributed in a circular shape inside the rotating ring 6. The three sets of baffles can drive the airflow to rotate the rotating ring 6 inside the auxiliary cylinder 3.
[0041] In one embodiment of the present invention, the cleaning adjustment assembly includes a blade 131 rotatably connected to the surface of a turntable 11. A toothed ring 132 is installed on the surface of the rotating rod at the end of the blade 131. A first electric push rod 133 is installed at one end of the turntable 11 near the inside of the drainage tube 2. The extended end of the first electric push rod 133 is connected to the inner wall of the sleeve 12. A rack 134 is installed in the notch inside the sleeve 12. A second electric push rod 135 is installed at the bottom of the negative pressure vacuum cleaner 10. A contact platform 136 is installed at the extended end of the second electric push rod 135. By changing the angle of the blade 131 through the cleaning adjustment assembly, the plasma dispersion range is expanded, so that it is always in contact with the inner wall of the drainage tube 2, so that the plasma can adjust its distribution in a timely manner with the change of airflow and always maintain contact with the inner wall.
[0042] Plasma may pass through the contaminated area quickly, which is not conducive to the complete elimination of pathogens. Furthermore, due to the high airflow speed, the plasma does not easily come into contact with the inner wall of the drainage tube 2. The inner wall of the drainage tube 2 remains in prolonged contact with microorganisms in the airflow, making them difficult to eliminate through subsequent disinfection. The specific implementation method is as follows: In use, the controller first drives the bidirectional motor output to rotate the rotating drum 4. The rotating drum 4 then drives the paddle 5 to rotate, promoting airflow. Subsequently, the plasma exciter 1 emits plasma into the drainage tube 2. The other output of the bidirectional motor drives the sleeve 12 to rotate, which in turn drives the turntable 11 to rotate. The rotation of the turntable 11 causes the plasma to... When the blade 5 rotates, it makes full contact with the inner wall of the diversion tube 2. The blade 5 is close to the bottom protrusion of the slide rod at one end of the rotating tube 4 and is vertically shaken by the contact platform 136. At this time, the controller drives the negative pressure vacuum cleaner 10 to operate and absorb the dust under the shaking of the blade 5. Then, when the airflow flows into the auxiliary tube 3, the airflow blows the rotating ring 6 to rotate inside the auxiliary tube 3. At this time, the rotation of the rotating ring 6 drives the fan 906 to rotate inside the diffusion platform 8, so that gas is generated inside the diffusion platform 8. The gas inside the diffusion platform 8 is discharged through the vent, so that the airflow inside the diversion tube 2 can diffuse outward when it is discharged, slowing down the airflow speed and allowing the plasma to fill the contaminated area.
[0043] In one embodiment of the present invention, both the diffuser platform 8 and the rotating ring 907 are provided with a 45° inclined surface, and the inclined surfaces of the diffuser platform 8 and the rotating ring 907 are provided with a plurality of ventilation holes. The ventilation holes can diffuse outward when the airflow inside the guide tube 2 is discharged, thus slowing down the airflow speed. The inclined surface at the end of the rotating ring 907 is in close contact with the inclined surface inside the diffuser platform 8. The surface of the diffuser platform 8 is provided with a groove, and the drive ring 908 passes through the groove and is connected to the rotating ring 907.
[0044] In one embodiment of the present invention, the connecting ring 901 is connected to the swing block 902 by a torsion spring. There are three sets of swing blocks 902, which are evenly distributed in a circular shape inside the connecting ring 901. The swing block 902 has an inclined surface on the side close to the connecting ring 901.
[0045] In one embodiment of the present invention, a thin rod is installed on one end of the contact frame 904 near the contact block 903. The surface of the thin rod slides within the mounting platform 7 and one end of the thin rod is connected to the contact block 903. A spring is installed on the side of the contact block 903 and the other end of the spring is connected to the inner wall of the mounting platform 7. An adjusting ring 905 is installed on the other end of the contact frame 904. An inclined groove is formed on the surface of the adjusting ring 905. The external protrusion of the drive ring 908 slides within the inclined groove on the surface of the adjusting ring 905. The end of the connecting ring 901 away from the diversion tube 2 is connected to the fan 906. When the connecting ring 901 rotates, it can drive the fan 906 to rotate together, so that gas is generated inside the diffuser platform 8.
[0046] In one embodiment of the present invention, the rack 134 meshes with the gear ring 132, the contact platform 136 is a half-frustum shape, and the contact platform 136 is located inside the rotating cylinder 4. Example
[0047] Based on Example 1, please refer to Figures 1-11 The method includes the following steps:
[0048] S1: Plasma exciter 1 emits plasma into the drainage tube 2. The bidirectional motor drives the rotating drum 4 and sleeve 12 to rotate. The rotation of sleeve 12 drives the turntable 11 to rotate, so that the plasma comes into full contact with the inner wall of the drainage tube 2, sterilizing the inside of the drainage tube 2. The rotation of rotating drum 4 drives the paddle 5 to rotate, so that the airflow carrying the plasma is discharged through the auxiliary tube 3, sterilizing the external environment.
[0049] S2: When the rotating drum 4 rotates at a high speed, the plasma is discharged before it comes into contact with the inner wall. The controller drives the cleaning and adjustment components to operate, increasing the diffusion force of the plasma so that it can fully contact the inner wall of the drainage tube 2 to achieve the sterilization effect.
[0050] S3: When the rotating drum 4 rotates at a high speed, the gas flow rate inside the diversion tube 2 is also high. The gas flow rate inside the auxiliary tube 3 is slowed down by the airflow regulating component, which increases the outward diffusion range and can fully sterilize the external environment.
[0051] Working principle: In use, the controller first drives the output end of the bidirectional motor to rotate the drum 4. The drum 4 drives the blades 5 to rotate to promote air flow. Then, the plasma exciter 1 emits plasma into the drainage tube 2. The output end of the other side of the bidirectional motor drives the sleeve 12 to rotate. The rotation of the sleeve 12 drives the turntable 11 to rotate. The rotation of the turntable 11 makes the plasma fully contact the inner wall of the drainage tube 2. When the blades 5 rotate, they are close to the bottom protrusion of the slide rod at one end of the drum 4 and are resisted by the contact platform 136 and shake vertically. At this time, the controller drives the negative pressure vacuum cleaner 10 to operate and absorb the dust under the shaking of the blades 5. Then, when the airflow flows into the auxiliary tube 3, the airflow blows the rotating ring 6 to rotate inside the auxiliary tube 3. At this time, the rotation of the rotating ring 6 drives the fan 906 to rotate inside the diffusion platform 8, which generates gas inside the diffusion platform 8. The gas inside the diffusion platform 8 is discharged through the vent, so that the airflow inside the drainage tube 2 can diffuse outward, slow down the airflow speed, and allow the plasma to fill the contaminated area.
[0052] When the rotating drum 4 rotates at a relatively high speed, the controller drives the first electric push rod 133 to extend and push the sleeve 12 to move on the surface of the turntable 11. At this time, the rack 134 drives the gear ring 132 to rotate, and the gear ring 132 drives the blade 131 to rotate. When the turntable 11 rotates, the plasma is always in full contact with the inner wall of the diversion tube 2. At the same time, the controller pushes the contact platform 136 to move into the rotating drum 4, increasing the contact force between the contact platform 136 and the bottom protrusion of the slide rod at one end of the rotating drum 4, and increasing the amplitude of the vertical swaying of the blade 5 inside the rotating drum 4.
[0053] Meanwhile, the gas flow speed inside the diversion tube 2 increases, causing the rotating ring 6 to rotate faster inside the auxiliary tube 3. The centrifugal force generated by the accelerated rotation of the connecting ring 901 throws out the throwing block 902. When the throwing block 902 is thrown out, its inclined surface abuts against the abutting block 903, causing it to move towards the diffuser platform 8. At this time, the abutting block 903 drives the abutting frame 904 to move outward. When the abutting frame 904 drives the adjusting ring 905 to move, the external protrusion of the driving ring 908 slides in the inclined groove on the surface of the adjusting ring 905, causing the driving ring 908 to rotate inside the auxiliary tube 3. The driving ring 908 drives the rotating ring 907 to rotate inside the diffuser platform 8, reducing the diameter of the vent hole and increasing the airflow pressure, so that the airflow inside the diversion tube 2 can diffuse smoothly outward when it is discharged.
[0054] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. An air circulation system for greenhouses, comprising a plasma exciter (1) and a drainage tube (2), characterized in that: An auxiliary cylinder (3) is installed at the end of the drainage cylinder (2) away from the plasma exciter (1). A rotating cylinder (4) is installed inside the plasma exciter (1) via a motor. A paddle (5) is installed inside the rotating cylinder (4). A rotating ring (6) is rotatably connected inside the auxiliary cylinder (3). An installation platform (7) is installed on the outer surface of the auxiliary cylinder (3). A diffusion platform (8) is installed inside the auxiliary cylinder (3). An airflow adjustment component is provided on the outer surface of the auxiliary cylinder (3). A negative pressure vacuum cleaner (10) is installed on the inner wall of the drainage cylinder (2) in the area to the right of the rotating cylinder (4). A turntable (11) is installed at the left end inside the drainage cylinder (2). A sleeve (12) is fitted on the surface of the turntable (11). A cleaning adjustment component is provided on the surface of the turntable (11). The airflow regulating assembly includes a connecting ring (901) installed outside the rotating ring (6), a swing block (902) rotatably connected inside the connecting ring (901), a stop block (903) slidingly limited inside the mounting platform (7), a stop frame (904) slidingly limited inside the mounting platform (7), a fan (906) rotatably connected inside the diffuser platform (8), a rotating ring (907) rotatably connected inside the diffuser platform (8), and a drive ring (908) rotatably connected inside the auxiliary cylinder (3). Both the diffuser platform (8) and the rotating ring (907) have 45° inclined surfaces at their ends, and the inclined surfaces of the diffuser platform (8) and the rotating ring (907) are provided with several ventilation holes. The inclined surface at the end of the rotating ring (907) is in close contact with the inclined surface inside the diffuser platform (8). The surface of the diffuser platform (8) is provided with a groove, and the drive ring (908) passes through the groove and is connected to the rotating ring (907). The connecting ring (901) is connected to the swing block (902) by a torsion spring. There are three sets of swing blocks (902). The three sets of swing blocks (902) are evenly distributed in a circular shape inside the connecting ring (901). The swing block (902) has an inclined surface on the side close to the connecting ring (901). The contact frame (904) has a thin rod installed near the contact block (903) at one end. The surface of the thin rod slides within the mounting platform (7) and one end of the thin rod is connected to the contact block (903). A spring is installed on the side of the contact block (903) and the other end of the spring is connected to the inner wall of the mounting platform (7). An adjusting ring (905) is installed at the other end of the contact frame (904). An inclined groove is provided on the surface of the adjusting ring (905). The external protrusion of the drive ring (908) slides within the inclined groove on the surface of the adjusting ring (905). The end of the connecting ring (901) away from the diversion tube (2) is connected to the fan (906).
2. The air circulation system for greenhouses according to claim 1, characterized in that: The blade (5) is equipped with a slide rod at one end near the rotating drum (4). The slide rod slides within the rotating drum (4) and is fitted with a spring. A protrusion is installed at one end of the slide rod near the inside of the rotating drum (4).
3. The air circulation system for greenhouses according to claim 1, characterized in that: The rotating ring (6) is equipped with three sets of spiral baffles, which are evenly distributed in a circular shape inside the rotating ring (6).
4. The air circulation system for greenhouses according to claim 1, characterized in that: The cleaning adjustment assembly includes a blade (131) rotatably connected to the surface of the turntable (11), a toothed ring (132) is installed on the surface of the rotating rod at the end of the blade (131), a first electric push rod (133) is installed at one end of the turntable (11) near the inside of the drainage tube (2), the extended end of the first electric push rod (133) is connected to the inner wall of the sleeve (12), a rack (134) is installed in the notch inside the sleeve (12), a second electric push rod (135) is installed at the bottom of the negative pressure vacuum cleaner (10), and an abutment (136) is installed at the extended end of the second electric push rod (135).
5. The air circulation system for greenhouses according to claim 4, characterized in that: The rack (134) meshes with the gear ring (132), and the contact platform (136) is a half-circular frustum and is located inside the rotating cylinder (4).
6. A sterilization method for greenhouses, applicable to the air circulation system for greenhouses as described in any one of claims 1-5, characterized in that: The method includes the following steps: S1: The plasma exciter (1) emits plasma into the drainage tube (2). The bidirectional motor drives the rotating drum (4) and the sleeve (12) to rotate. The rotation of the sleeve (12) drives the turntable (11) to rotate, so that the plasma can fully contact the inner wall of the drainage tube (2) to sterilize the inside of the drainage tube (2). The rotation of the rotating drum (4) drives the paddle (5) to rotate, so that the airflow carrying the plasma is discharged through the auxiliary tube (3) to sterilize the external environment. S2: When the rotating drum (4) rotates at a high speed, the plasma is discharged before it comes into contact with the inner wall. The controller drives the cleaning and adjustment components to operate, increasing the diffusion force of the plasma so that it can fully contact the inner wall of the drainage tube (2) to achieve sterilization. S3: When the rotating drum (4) rotates at a high speed, the gas flow rate inside the diversion tube (2) is high. The gas flow rate inside the auxiliary tube (3) is slowed down by the airflow adjustment component, increasing its outward diffusion range, which can fully sterilize the external environment.