A rotary tiller based on axial airflow for preventing grass entanglement

Abstract

The present invention discloses a rotary tiller based on axial air flow for preventing grass entanglement, which includes a frame. A driving mechanism, a cutter shaft and a rear cover plate are provided on the frame. Rotary tilling blades are provided on the cutter shaft. The driving mechanism is connected to the cutter shaft and can drive the cutter shaft to rotate. The rear cover plate covers the side of the cutter shaft and the rotary tilling blades away from the advancing direction of the frame. A blower, an air duct and an air box are also provided on the frame. The air outlet of the blower is communicated with the air box through the air duct. A plurality of nozzles are provided on the air box. Each nozzle is located above the rotary tilling blade, and the orientation of each nozzle is opposite to the advancing direction of the frame. The high-speed air flow generated by the blower in the present invention blows air towards the rear lower part of the cutter shaft through the nozzles, disturbing the circumferential flow of the air driven by the rotary tilling blades during rotation, preventing the situation that straw and other weeds rotate around the cutter shaft and wind around the machine components, reducing the maintenance cost and the loss of working efficiency. It not only solves the entanglement problem, but also improves the operation efficiency and reliability of the rotary tiller.

Description

Technical Field

[0001] The invention relates to the technical field of agricultural machinery, and in particular to a rotary tiller based on axial airflow to prevent grass entanglement. Background Art

[0002] In recent years, with the country's continuous advocacy and investment in modern agricultural construction, agricultural machinery has been widely promoted and applied in rural areas. Among them, the widespread use of rotary tillers has not only greatly improved the efficiency of farmland operations, but also greatly reduced the labor intensity of farmers. Compared with traditional manual tillage, rotary tillers can complete large-scale farmland operations in a shorter time, saving a lot of manpower and time costs. At the same time, its precise control and efficient working performance also ensure the quality and effect of farmland operations.

[0003] However, some problems often occur during the operation of rotary tillers. For example, since the rotary tiller needs to be in contact with the ground for tilling, its blades or rake teeth can easily roll weeds or crop residues into it when rotating at high speed, causing weed entanglement. This will not only affect the working efficiency of the rotary tiller, but may also cause damage to mechanical parts and increase maintenance costs. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a rotary tiller based on axial airflow to prevent grass entanglement, so that debris is not easy to rotate around the blade shaft, thereby preventing it from being entangled on the blade shaft.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A rotary tiller for preventing grass entanglement based on axial airflow comprises a frame, the frame is provided with a driving mechanism, a knife shaft and a rear cover plate, the knife shaft is provided with a rotary tiller, the driving mechanism is connected to the knife shaft and can drive the knife shaft to rotate, the rear cover plate is arranged on the side of the knife shaft and the rotary tiller away from the forward direction of the frame, the frame is also provided with a fan, an air duct and a bellows, the air outlet of the fan is connected with the bellows through the air duct, the bellows is provided with a plurality of nozzles, each of the nozzles is located above the rotary tiller, and each of the nozzles faces the direction opposite to the forward direction of the frame.

[0007] As a further improvement of the above technical solution:

[0008] The center line of each nozzle passes between a first tangent point and a second tangent point, wherein the first tangent point is the tangent point between the center line of the nozzle and the rear side of the blade shaft, and the second tangent point is the tangent point between the center line of the nozzle and the rear side of the rotating circle of the rotary blade.

[0009] The center line of each nozzle passes through the first tangent point.

[0010] The bellows is provided with multiple rows of nozzles. Each row of the nozzles extends along the axial direction of the cutter shaft. The multiple rows of nozzles are arranged in the direction perpendicular to the axial direction of the cutter shaft. The centerlines of several rows of nozzles close to the advancing direction of the frame all pass through the first tangent point, and the centerlines of several rows of nozzles far from the advancing direction of the frame all pass through the second tangent point.

[0011] The orientations of all the nozzles are the same.

[0012] A lifting plate and a telescopic rod are provided in the bellows. The lifting plate is located inside the bellows and forms an air storage cavity with the bottom side inside the bellows. The air duct and the nozzles are both communicated with the air storage cavity. The base of the telescopic rod is connected to the bellows, and the driving end of the telescopic rod is connected to the lifting plate and can drive the lifting plate to move up and down to increase or decrease the space of the air storage cavity.

[0013] A one-way pressure valve is provided at one end of each nozzle close to the bellows. The one-way pressure valve is connected to the bellows.

[0014] A diversion port is provided on the rear cover plate. The diversion port extends along the axial direction of the cutter shaft.

[0015] A baffle is provided on the rear cover plate. The baffle is located above the side of the diversion port far from the advancing direction of the frame. The baffle can freely switch between a closed state and an open state. The closed state is the state where the baffle covers the diversion port when the rotary tillage cutter is not rotating, and the open state is the state where the baffle is pushed open by the airflow generated when the rotary tillage cutter rotates to open the diversion port.

[0016] The rear cover plate is movably connected to the frame, and a driving device capable of adjusting the opening and closing angle of the rear cover plate is provided on the frame.

[0017] Compared with the prior art, the advantages of the present invention are as follows:

[0018] The present invention solves common problems in the operation process of a rotary tiller, such as the entanglement of weeds or crop residues. It blows the weeds downward in the direction of the rear cover plate through the high-speed airflow generated by the nozzles, which helps to reduce the entanglement problem of the cutter shaft. The design of the rear cover plate controls the flow direction and outflow speed of the airflow, and at the same time prolongs the movement time of the soil crushing, covering it on the weeds, thereby further reducing the possibility of entanglement.

[0019] Specifically, in the design of this rotary tiller, the combination of the blower and the nozzle achieves effective weed removal. The high-speed air flow generated by the blower blows through the nozzle towards the lower rear of the cutter shaft, disturbing the circumferential flow of the surrounding air driven by the rotation of the rotary tiller blades, preventing weeds such as straw from rotating around the cutter shaft and winding around the machine components. This design not only solves the winding problem but also improves the operation efficiency and reliability of the rotary tiller. Through the high-speed air flow generated by the nozzle, the situation of weeds or crop residues winding around the cutter shaft is effectively prevented, reducing the maintenance cost and the loss of work efficiency; by removing weeds, the operation efficiency of the rotary tiller is improved because there is no need to stop to clean the weeds winding around the cutter shaft, saving time; the implementation of this design is simple and effective, not only improving the reliability of the machine but also reducing the maintenance requirements of the operator for the machine, making the machine easier to operate and maintain; these advantages make this rotary tiller have a broader application prospect and market competitiveness in modern agricultural production. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 FIG. is a right view structural schematic diagram of a rotary tiller for preventing grass entanglement based on axial air flow.

[0021] Figure 2 is Figure 1 a three-dimensional structural view.

[0022] Figure 3 is Figure 1 a bottom view structural view.

[0023] Figure 4 FIG. is a three-dimensional structural schematic diagram of a rotary tiller for preventing grass entanglement based on axial air flow.

[0024] Figure 5 is Figure 4 a longitudinal sectional structural view.

[0025] LEGEND DESCRIPTION:

[0026] 1. Frame; 2. Cutter shaft; 21. Rotary tiller blade; 3. Rear cover plate; 31. Diversion port; 32. Baffle; 4. Blower; 41. Air duct; 42. Air box; 421. Air storage cavity; 43. Nozzle; 44. Lifting plate; 45. Telescopic rod; 46. One-way pressure valve. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] As Figures 1 - 5As shown in the figure, the rotary tiller based on axial airflow for preventing grass entanglement in this embodiment includes a frame 1, on which a driving mechanism, a cutter shaft 2 and a rear cover plate 3 are provided. The cutter shaft 2 is provided with rotary tiller blades 21. The driving mechanism is connected to the cutter shaft 2 and can drive the cutter shaft 2 to rotate. The rear cover plate 3 covers the side of the cutter shaft 2 and the rotary tiller blades 21 away from the advancing direction of the frame 1. The frame 1 is also provided with a blower 4, an air duct 41 and an air box 42. The air outlet of the blower 4 is communicated with the air box 42 through the air duct 41. The air box 42 is provided with a plurality of nozzles 43. Each nozzle 43 is located above the rotary tiller blade 21, and the orientation of each nozzle 43 is opposite to the advancing direction of the frame 1. The present invention solves the common problems in the operation process of the rotary tiller, such as the entanglement of weeds or crop residues. It blows the weeds downward in the direction of the rear cover plate 3 through the high-speed airflow generated by the nozzles 43, which helps to reduce the entanglement problem of the cutter shaft 2. The design of the rear cover plate 3 controls the flow direction and outflow speed of the airflow, and at the same time prolongs the movement time of soil fragmentation, covering it on the weeds, thereby further reducing the possibility of entanglement.

[0029] Specifically, the combination of the blower 4 and the nozzles 43 in the design of this rotary tiller realizes the effective removal of weeds. The high-speed airflow generated by the blower 4 blows air downward and backward of the cutter shaft 2 through the nozzles 43, disturbing the circumferential flow of the surrounding air driven by the rotation of the rotary tiller blade 21, and preventing the situation where weeds such as straw rotate around the cutter shaft 2 and entangle on the machine components. This design not only solves the entanglement problem, but also improves the operation efficiency and reliability of the rotary tiller. Through the high-speed airflow generated by the nozzles 43, the situation where weeds or crop residues entangle the cutter shaft 2 is effectively prevented, reducing the maintenance cost and the loss of work efficiency; by removing weeds, the operation efficiency of the rotary tiller is improved because there is no need to stop to clean the weeds entangled on the cutter shaft 2, saving time; the implementation of this design is simple and effective, not only improving the reliability of the machine, but also reducing the maintenance requirements of the operator for the machine, making the machine easier to operate and maintain; these advantages make this rotary tiller have a broader application prospect and market competitiveness in modern agricultural production.

[0030] In this embodiment, the centerlines of the nozzles 43 pass between the first tangent point and the second tangent point. The first tangent point is the tangent point between the centerline of the nozzle 43 and the rear side of the tool shaft 2, and the second tangent point is the tangent point between the centerline of the nozzle 43 and the rear side of the rotation circle of the rotary tillage blade 21. The orientation of the nozzle 43 plays a crucial role in interfering with the surrounding swirling flow. By adjusting the orientation of the nozzle 43, the formation of the surrounding swirling flow can be more effectively interfered, thereby preventing weeds or crop residues from rotating around the tool shaft 2 and winding around the machine components. First, when the nozzle 43 is oriented downward and backward with respect to the tool shaft 2, it can directly interfere with the swirling flow formed by the rotation of the rotary tillage blade 21 driving the surrounding air. Such a setting makes the air flow generated by the nozzle 43 oppose the swirling flow driven by the tool shaft 2, forming a confrontation relationship. This confrontation relationship leads to the destruction of the swirling flow field, making it impossible for the swirling flow to form stably, thereby preventing weeds or crop residues from rotating around the tool shaft 2. Second, the position of the nozzle 43 passes through a certain position between the first tangent point and the second tangent point. Such a design takes into account the relative position relationship between the nozzle 43, the tool shaft 2, and the rotary tillage blade 21. By ensuring that the position of the nozzle 43 intersects the movement trajectory of the rotary tillage blade 21, it can be ensured that the air flow generated by the nozzle 43 can fully affect the swirling flow around the rotary tillage blade 21, further enhancing the interference effect.

[0031] Therefore, through such a design, the air flow generated by the nozzle 43 below the rear of the tool shaft 2 can effectively destroy the swirling flow field, making it difficult for weeds or crop residues to rotate around the tool shaft 2, thereby avoiding the occurrence of winding problems.

[0032] In this embodiment, the centerlines of the nozzles 43 all pass through the first tangent point. All the nozzles 43 are oriented in the same direction, which ensures that the directions of the air flows generated by the nozzles 43 are the same, thereby improving the consistency and uniformity of the interference effect. This means that the swirling flow around the entire rotary tillage blade 21 is affected similarly, and weeds or crop residues will be effectively interfered in any direction, reducing the possibility of winding. The design of all the nozzles 43 being oriented towards one place can concentrate the generation of air flow and enhance the interference effect on the swirling flow around the rotary tillage blade 21. The concentrated air flow can more effectively destroy the swirling flow field, prevent weeds or crop residues from rotating around the tool shaft 2 and winding around the machine components, thereby improving the operation efficiency and reliability. In summary, the design that the centerlines of the nozzles 43 pass through the first tangent point and all are oriented towards one place simplifies the operation process, improves the consistency and uniformity of the system, and enhances the interference effect on the swirling flow, making the rotary tillage machine more efficient and reliable during operation.

[0033] In this embodiment, there are multiple rows of nozzles 43 provided on the bellows 42. Each row of nozzles 43 extends along the axial direction of the cutter shaft 2. The multiple rows of nozzles 43 are arranged in the direction perpendicular to the axial direction of the cutter shaft 2. The centerlines of several rows of nozzles 43 close to the advancing direction of the frame 1 all pass through the first tangent point, and the centerlines of several rows of nozzles 43 far from the advancing direction of the frame 1 all pass through the second tangent point. The multiple rows of nozzles 43 are arranged along the axial direction of the cutter shaft 2, which can achieve uniform coverage of the working area. The nozzles 43 close to the advancing direction of the frame 1 cover the area near the cutter shaft 2, while the nozzles 43 far from the advancing direction of the frame 1 cover the area far from the cutter shaft 2, thus ensuring uniform cleaning of the entire working area. Through the design that the nozzles 43 close to the cutter shaft 2 and far from the cutter shaft 2 pass through the first tangent point and the second tangent point respectively, the interference effect of the airflow generated by the nozzles 43 on the circumferential flow can be more precisely controlled. Such an arrangement enables the nozzles 43 close to the cutter shaft 2 to mainly be responsible for interfering with the circumferential flow nearby, while the nozzles 43 far from the cutter shaft 2 are mainly responsible for interfering with the circumferential flow in the distance, thereby improving the operating efficiency of the entire system. Since the arrangement of the nozzles 43 takes into account the characteristics of the working area, the airflow can more precisely interfere with the circumferential flow of weeds or crop residues. Such a design can reduce unnecessary airflow consumption, lower the energy consumption, and at the same time extend the service life of the fan 4 and the system. The multiple rows of nozzles 43 on the bellows 42 extend along the axial direction of the cutter shaft 2, and the arrangement of the nozzles 43 is optimized according to the position, which can achieve the advantages of uniform coverage, efficient operation, energy saving and consumption reduction, and improve the operating efficiency and reliability of the rotary tiller.

[0034] In this embodiment, the orientations of all the nozzles 43 are the same. All the nozzles 43 face one direction, and the inclination angle of their centerlines is 45°. This design simplifies the construction and operation of the system. The operator does not need to consider the direction adjustment or balance of the nozzles 43, which simplifies the operation process and reduces the possibility of operation errors. At the same time, this also reduces the maintenance cost, because the maintenance personnel only need to pay attention to the overall state of the nozzles 43, rather than checking and adjusting the orientations of each nozzle 43 one by one.

[0035] In this embodiment, a lifting plate 44 and a telescopic rod 45 are provided in the bellows 42. The lifting plate 44 is located inside the bellows 42 and forms an air storage cavity 421 with the bottom side inside the bellows 42. Both the air duct 41 and the nozzle 43 are communicated with the air storage cavity 421. The base of the telescopic rod 45 is connected to the bellows 42, and the driving end of the telescopic rod 45 is connected to the lifting plate 44 and can drive the lifting plate 44 to move up and down to increase or decrease the space of the air storage cavity 421. Through the structural design of the lifting plate 44 and the telescopic rod 45, the flexible adjustment of the space size of the air storage cavity 421 can be realized. When it is necessary to increase or decrease the space of the air storage cavity 421, the telescopic rod 45 can be driven to move the lifting plate 44 up and down, so as to adjust the size of the air storage cavity 421. This flexible adjustability enables the rotary tiller to adapt to different operating environments and requirements, improving the applicability and versatility of the system. By adjusting the space size of the air storage cavity 421, the distribution of air flow in the bellows 42 can be optimized. When a larger air storage cavity 421 is needed, the space of the air storage cavity 421 can be increased, so that the air flow in the bellows 42 can circulate more fully and be evenly distributed. On the contrary, when a smaller air storage cavity 421 is needed, the space of the air storage cavity 421 can be reduced, so as to more intensively guide the air flow to the nozzle 43, enhancing the interference effect on the surrounding flow. By optimizing the air flow distribution, the flow resistance of the air flow in the bellows 42 can be reduced, and the energy consumption can be reduced. When the air flow distribution is optimized, the fan 4 can reduce the power output under the condition of maintaining the same operating effect, achieving the purpose of energy saving and consumption reduction. For a rotary tiller operating for a long time, this can effectively reduce the energy consumption and operating costs. The design of the lifting plate 44 and the telescopic rod 45 in the bellows 42 improves the flexibility and adjustability of the system, optimizes the air flow distribution, and at the same time achieves the effect of energy saving and consumption reduction, thereby improving the operating efficiency and sustainability of the rotary tiller. The telescopic rod 45 is electric and is directly powered by the tractor, used to control the lifting plate 44 to move up and down to change the size of the air storage cavity 421 inside the bellows 42, and cooperate with the fan 4 to change the pulse frequency of the ejected high-speed air flow.

[0036] In this embodiment, a one-way pressure valve 46 is provided at one end of each nozzle 43 close to the bellows 42, and the one-way pressure valve 46 is connected to the bellows 42. The power of a single fan is 1100 kw, and the pulse frequency of the ejected high-speed air flow. The one-way pressure valve 46 is pneumatic, with an inner diameter of 30 mm. 6 rows and 10 columns are installed below the bellows 42, with a row spacing of 80 mm and a column spacing of 100 mm. The one-way pressure valve 46 is installed at an angle of 45° obliquely backward to the cover plate 3 with respect to the horizontal plane. Only when the internal pressure of the bellows 42 exceeds 0.0182 kN / m 2 can the one-way pressure valve 46 be opened, and when the pressure is less than 0.0182 kN / m 2The one-way pressure valve 46 will close at this time, thus generating a pulsed high-speed air flow. At the same time, the one-way pressure valve 46 can ensure that air flow is only allowed to spray downward from the air box 42 during operation, and can prevent soil fragments from entering the air box 42 when not working.

[0037] In this embodiment, a speed sensor is provided on the frame 1 to measure the rotational speed of the cutter shaft 2 and the traveling speed of the frame 1, thereby changing the pulse frequency.

[0038] In this embodiment, there are two blowers 4, and the two blowers 4 are respectively arranged at both ends of the air box 42 along the axial direction of the cutter shaft 2, and each air duct 41 is arranged at the end of the air box 42 along the axial direction of the cutter shaft 2. One blower 4 is connected to the air box 42 through two air ducts 41.

[0039] In this embodiment, a diversion port 31 is provided on the rear cover plate 3, and the diversion port 31 extends along the axial direction of the cutter shaft 2. The diversion port 31 can pass through the thrown soil fragments and weeds. The diversion port 31 is used to change the air flow direction and the outflow speed, and at the same time extend the movement time of part of the soil fragments, so that they cover the weeds. When the rotary tiller blade 21 is working, part of the soil fragments will continue to be thrown backward through the diversion port 31 on the rear cover plate 3, and will move for a longer time compared with the soil fragments and weeds that impact the rear cover plate 3 (or the soil fragments and weeds directly blown to the ground by the high-speed air flow), so as to cover the weeds above, so as to play the role of preventing grass entanglement and burying grass.

[0040] In this embodiment, a baffle 32 is provided on the rear cover plate 3. The baffle 32 is located above the side of the diversion port 31 away from the advancing direction of the frame 1. The baffle 32 can freely switch between a closed state and an open state. The closed state is the state where the baffle 32 covers the diversion port 31 when the rotary tiller blade 21 is not rotating, and the open state is the state where the baffle 32 is pushed open by the air flow generated when the rotary tiller blade 21 rotates to open the diversion port 31. The baffle 32 can automatically adjust to open or close according to the rotation state of the rotary tiller blade 21. When the rotary tiller blade 21 rotates, the generated air flow will push the baffle 32 to open the diversion port 31 to release the air flow and prevent the baffle 32 from being driven by the air flow to cause mechanical damage. This automatically adjustable design simplifies the operation process and improves the stability and safety of the rotary tiller. The open state of the baffle 32 can enhance the control of the air flow at the diversion port 31. When the baffle 32 is open, the area of the diversion port 31 increases, and the air flow can flow out more smoothly, improving the effect of weed removal and further reducing the possibility of weeds rotating around the cutter shaft 2. Therefore, the design of the baffle 32 provided on the rear cover plate 3 plays an important role in the operation of the rotary tiller, can effectively remove weeds, automatically adjust the air flow, and enhance the air flow control, thereby improving the operation efficiency and reliability of the rotary tiller.

[0041] In this embodiment, the rear cover plate 3 is used to block the soil fragments and weeds thrown by the rotary tiller blade 21 and is composed of two independent cover plates.

[0042] In this embodiment, the rear cover plate 3 is movably connected to the frame 1, and a driving device capable of adjusting the opening and closing angle of the rear cover plate 3 is provided on the frame 1. The opening and closing angle of the rear cover plate 3 can be adjusted. When the rear cover plate 3 is closed, the airflow will flow from the front and both sides of the rotary tiller, which will increase the movement distance of the weeds and thus increase the probability of grass entanglement. When the rear cover plate 3 is opened, the airflow direction will also flow out from the direction of the diversion port 31, thereby driving the weeds to fly below the diversion port 31, reducing the probability of grass entanglement on the cutter shaft 2. At the same time, different opening and closing angles of the rear cover plate 3 will change the speed of the airflow flowing out towards the rear cover plate 3, and the required angle can be adjusted according to the actual operation conditions.

[0043] The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. For those skilled in the art of this technology, the improvements and transformations obtained without departing from the technical concept of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A rotary tiller based on axial airflow to prevent grass entanglement, comprising a frame (1), the frame (1) being provided with a driving mechanism, a knife shaft (2) and a rear cover plate (3), the knife shaft (2) being provided with a rotary tiller (21), the driving mechanism being connected to the knife shaft (2) and being able to drive the knife shaft (2) to rotate, the rear cover plate (3) being provided on a side of the knife shaft (2) and the rotary tiller (21) away from a forward direction of the frame (1), characterized in that: The frame (1) is further provided with a fan (4), an air duct (41) and a wind box (42); the air outlet of the fan (4) is connected to the wind box (42) through the air duct (41); the wind box (42) is provided with a plurality of rows of nozzles (43); each of the nozzles (43) is located above the rotary tiller blade (21); each row of the nozzles (43) extends along the axial direction of the blade shaft (2); the plurality of rows of the nozzles (43) are arranged along the axial direction perpendicular to the blade shaft (2), and are arranged close to the frame (1). The center lines of the rows of nozzles (43) in the forward direction of the frame (1) all pass through the first tangent point, and the center lines of the rows of nozzles (43) away from the forward direction of the frame (1) all pass through the second tangent point; the direction of each of the nozzles (43) is opposite to the forward direction of the frame (1), and the directions of each of the nozzles (43) are consistent; the first tangent point is the tangent point between the center line of the nozzle (43) and the rear side of the blade shaft (2), and the second tangent point is the tangent point between the center line of the nozzle (43) and the rear side of the rotating circle of the rotary blade (21); The rear cover plate (3) is provided with a guide port (31), and the guide port (31) extends axially along the blade shaft (2); the rear cover plate (3) is provided with a baffle plate (32), and the baffle plate (32) is located above the guide port (31) on a side away from the forward direction of the frame (1), and the baffle plate (32) can be freely switched between a closed state and an open state, wherein the closed state is a state in which the baffle plate (32) covers the guide port (31) when the rotary tiller (21) is not rotating, and the open state is a state in which the baffle plate (32) is pushed by the airflow generated when the rotary tiller (21) rotates to open the guide port (31); The wind box (42) is provided with a lifting plate (44) and a telescopic rod (45); the lifting plate (44) is located inside the wind box (42) and forms an air storage cavity (421) with the bottom side of the wind box (42); the air duct (41) and the nozzle (43) are both in communication with the air storage cavity (421); the base of the telescopic rod (45) is connected to the wind box (42); the driving end of the telescopic rod (45) is connected to the lifting plate (44) and can drive the lifting plate (44) to move up and down to increase or decrease the space of the air storage cavity (421).

2. The rotary tiller based on axial airflow to prevent grass entanglement according to claim 1, characterized in that: A one-way pressure valve (46) is provided at one end of each nozzle (43) close to the bellows (42), and the one-way pressure valve (46) is connected to the bellows (42).

3. The rotary tiller based on axial airflow to prevent grass entanglement according to claim 1, characterized in that: The rear cover plate (3) is movably connected to the frame (1), and a driving device capable of adjusting the opening and closing angle of the rear cover plate (3) is provided on the frame (1).

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