Seed metering device, seeding system and seeding method

Abstract

The application relates to the technical field of agricultural equipment, and provides a seed sowing device, a sowing system and a sowing method. The seed sowing device comprises a shell, a seed sowing disc, a driving piece, a gas blocking piece and a seed guiding pipe. The shell is provided with a containing cavity. The shell is provided with an air inlet, an air outlet and a seed discharging port. The air inlet is used for being communicated with the outlet of a fan, and the air outlet is used for being communicated with the inlet of the same fan. The seed sowing disc is arranged in the containing cavity, and the containing cavity is divided into a seed sowing cavity and a negative pressure cavity. The air inlet and the seed discharging port are both communicated with the seed sowing cavity, and the air outlet is communicated with the negative pressure cavity. The seed sowing disc is provided with a plurality of adsorption holes. The driving piece is in transmission connection with the seed sowing disc and is used for driving the seed sowing disc to rotate around the axis. The gas blocking piece is fixedly arranged in the shell and located in the negative pressure cavity. When any adsorption hole moves to a seed discharging area, the gas blocking piece blocks the communication path between the adsorption hole and the negative pressure cavity. The seed guiding pipe is arranged in the shell and at least partially extends into the seed sowing cavity. The inlet of the seed guiding pipe is located below the corresponding position of the gas blocking piece and is arranged close to the movement track of the adsorption hole.

Description

Technical Field

[0001] This invention relates to the field of agricultural equipment technology, and in particular to a seed metering device, a seeding system, and a seeding method. Background Technology

[0002] Pneumatic seed metering devices have been widely used in precision seeding operations due to their advantages such as good adaptability to seed size, low seed damage rate, and high operating speed. Their basic working principle is as follows: negative pressure is used to adhere the seeds to the suction holes of the seed metering disc. After the disc rotates to the seeding area, the negative pressure is removed or positive pressure is applied to force the seeds to detach from the suction holes, thus completing the seeding process.

[0003] In existing pneumatic seed metering technology, two independent air source systems are used, with the positive and negative pressure sources separated. Each system is equipped with independent power components and control valve groups. The two systems are completely independent in physical structure, and the alternation of adsorption and seeding states is achieved only through air path switching at the suction holes of the seed metering disc. This solution has a large number of devices, low system integration, and large space occupation; the dual power sources lead to a significant increase in overall energy consumption; the independent air blowing system requires additional auxiliary components such as filters and pressure regulating valves, resulting in high manufacturing and maintenance costs.

[0004] In related technologies, positive and negative pressures are applied to different stages or parts of the seeds to complete the sowing process. For example, negative pressure is maintained in the adsorption zone of the seed metering disc to achieve seed retrieval and carrying, while positive pressure is switched in the sowing zone to blow the seeds off. In this scheme, the positive and negative pressures essentially act independently at different times or spatial locations, resulting in zero contribution of positive pressure airflow to improving adsorption force during the adsorption stage, and the utilization efficiency of pressure difference resources is not substantially improved.

[0005] It is evident that existing pneumatic seeding devices still face technical challenges in utilizing both positive and negative pressure, including complex structures, high costs, and high energy consumption. Summary of the Invention

[0006] This invention provides a seed metering device, a seeding system, and a seeding method to solve the problems of complex structure, high cost, and high energy consumption of existing seed metering devices.

[0007] This invention provides a seed metering device, comprising: a housing having a receiving cavity, the housing having an air inlet, an air outlet, and a seed dispensing port, the air inlet being connected to the outlet of a blower, the air outlet being connected to the inlet of the same blower, and the seed dispensing port being connected to a seed box; a seed metering disc disposed within the receiving cavity, dividing the receiving cavity into a seed metering chamber located on one side of the seed metering disc and a negative pressure chamber located on the other side of the seed metering disc, the air inlet and the seed dispensing port being connected to the seed metering chamber, and the air outlet being connected to the negative pressure chamber; the seed metering disc having a plurality of adsorption holes penetrating its surface, each adsorption hole being connected to the seed metering chamber and the negative pressure chamber; a driving member being drivenly connected to the seed metering disc for driving the seed metering disc to rotate around its own axis; and an air-blocking member being fixedly disposed in the housing and located within the negative pressure chamber. The air-blocking component is used to block the communication path between the adsorption hole and the negative pressure chamber when any of the adsorption holes moves to the seed discharge area. The seed discharge tube passes through the housing and extends at least partially into the seed discharge chamber. The inlet of the seed discharge tube is located below the corresponding position of the air-blocking component and is set close to the movement trajectory of the adsorption hole. The outlet of the fan supplies positive pressure airflow to the seed discharge chamber through the air inlet, and the inlet of the same fan draws negative pressure into the negative pressure chamber through the air outlet, so that an adsorption pressure difference is simultaneously formed on both sides of the adsorption hole from the seed discharge chamber to the negative pressure chamber. When the adsorption hole moves to the seed discharge area and is blocked by the air-blocking component, the communication between the adsorption hole and the negative pressure chamber is cut off, and the positive pressure airflow in the seed discharge chamber blows the seeds at the adsorption hole away and sends them into the seed discharge tube.

[0008] According to a seed metering device provided by the present invention, a negative pressure hood is further included. The negative pressure hood is disposed in the negative pressure cavity, covers the seed metering disc, and is fixedly connected to the seed metering disc. The negative pressure hood and the seed metering disc surround to form a rotating negative pressure cavity. The negative pressure hood is connected to the air outlet through a rotating seal to keep the rotating negative pressure cavity in a negative pressure state when it rotates with the seed metering disc.

[0009] According to a seed metering device provided by the present invention, the seed guide tube is disposed on the housing in a direction perpendicular to the ground, the disc surface of the seed metering disk is inclined relative to the central axis of the seed guide tube, and there is an angle A between the central axis of the seed guide tube and the disc surface, wherein the angle A is an acute angle.

[0010] According to the seed metering device provided by the present invention, 10°≤A≤20°.

[0011] According to a seed metering device provided by the present invention, the inlet end of the seed guide tube is provided with an avoidance section on the side near the seed metering disc, and there is a distance D between the avoidance section and the surface of the seed metering disc, wherein the distance D is less than the minimum size of the seed.

[0012] According to a seed metering device provided by the present invention, the avoidance section is parallel to the surface of the seed metering disc, and 0.5mm≤D≤2mm.

[0013] According to a seed metering device provided by the present invention, the seed guide tube includes a conveying tube and a guiding tube that are interconnected. The inlet of the conveying tube passes through the housing and is located in the seed metering cavity. The outlet of the guiding tube is used to guide the seeds to flow out. The cross-section of the guiding tube gradually changes along the flow direction.

[0014] According to a seeding device provided by the present invention, the inner wall surface of the guide tube includes a first inner wall surface and a second inner wall surface, the first inner wall surface and the second inner wall surface are sequentially connected to form a pipe with openings at both ends; the radius of curvature of the first inner wall surface is greater than the radius of curvature of the second inner wall surface, and the first inner wall surface is located above the second inner wall surface.

[0015] According to a seeding device provided by the present invention, the inner wall surface of the guide tube includes a third inner wall surface, a fourth inner wall surface, and a fifth inner wall surface. The third inner wall surface, the fourth inner wall surface, and the fifth inner wall surface are sequentially connected to form a pipe with openings at both ends. The third inner wall surface and the fifth inner wall surface are respectively disposed on both sides of the fourth inner wall surface. The fourth inner wall surface is an arc surface and is located above the third inner wall surface and the fifth inner wall surface. There is an included angle B between the third inner wall surface and the fifth inner wall surface.

[0016] According to the seed metering device provided by the present invention, 60°≤B≤120°.

[0017] According to a seed metering device provided by the present invention, along the rotation direction of the seed metering disc, the seed metering chamber includes a seed filling area, a seed cleaning area and a seed unloading area connected in sequence, wherein the seed filling area is located at the lower part, the seed cleaning area is provided with a seed cleaning component, and the seed guide tube is located in the seed unloading area.

[0018] The present invention also provides a seeding system, including a fan and a seed metering device as described above, wherein the inlet of the fan is connected to the outlet, and the outlet of the fan is connected to the inlet.

[0019] According to the present invention, a seeding system is provided, wherein there are multiple seed metering devices, and the seeding system further includes a positive pressure pipeline assembly and a negative pressure pipeline assembly. The air outlet of each seed metering device is connected to the inlet of the fan through the negative pressure pipeline assembly, and the air inlet of each seed metering device is connected to the outlet of the fan through the positive pressure pipeline assembly.

[0020] According to the present invention, a seeding system is provided, wherein the positive pressure pipeline assembly includes a positive pressure pipe and a plurality of air inlet pipes, the inlet of the positive pressure pipe is connected to the outlet of the fan, the inlet of each air inlet pipe is connected to the outlet of the positive pressure pipe, and the air inlet of each seed metering device is connected to the outlet of one of the air inlet pipes; and / or, the negative pressure pipeline assembly includes a negative pressure pipe and a plurality of air outlet pipes, the outlet of the negative pressure pipeline is connected to the inlet of the fan, the outlet of each air outlet pipe is connected to the inlet of the negative pressure pipe, and the air outlet of each seed metering device is connected to the inlet of one of the air outlet pipes.

[0021] According to the present invention, a seeding system is provided, which further includes a frame and a seed pressing component. The fan, the seed metering device and the seed pressing component are all disposed on the frame, and the seed pressing component is disposed downstream of the outlet of the seed guide tube.

[0022] The present invention also provides a sowing method based on the sowing system described in any of the above claims, comprising: starting a fan to create a negative pressure environment in the negative pressure chamber and a positive pressure environment in the seed dispensing chamber; driving the seed dispensing disc to rotate, under the action of negative pressure, the seeds are adsorbed onto the adsorption holes; when the adsorption holes rotate to the air-blocking element, under the action of positive pressure, the seeds in the adsorption holes detach from the seed dispensing disc and enter the seed guide tube, and are discharged from the shell.

[0023] The seed metering device, sowing system, and sowing method provided by this invention divide the receiving cavity into a seed metering chamber and a negative pressure chamber through a seed metering disc. Positive pressure is generated by connecting the outlet of a fan to the seed metering chamber, while negative pressure is generated by connecting the inlet of the fan to the negative pressure chamber. This creates a superimposed force with the same direction at the same adsorption point, significantly increasing the effective adsorption pressure difference at the adsorption pore. Compared to traditional solutions where only one side of the adsorption pore is connected to negative pressure while the other side is exposed to normal or atmospheric pressure, the net adsorption force is significantly improved, enhancing seed adsorption reliability, effectively reducing missed sowing rates, and adapting to higher operating speeds. When the adsorption orifice moves to the seed unloading area and is blocked by the air-blocking component, losing its negative pressure adsorption, the continuous positive pressure airflow in the seed discharge chamber directly acts on the seeds, applying a downward active blowing force. Combined with the seeds' own gravity and centrifugal force, the seeds quickly detach from the adsorption orifice. The seed guide tube is positioned directly below the corresponding position of the air-blocking component. While blowing the seeds down, the positive pressure airflow also provides directional airflow guidance for the seeds' descent, ensuring that the seeds fall precisely into the inlet of the seed guide tube along a predetermined trajectory. This shortens the seed delivery path, reduces interference during seed transfer, and improves sowing accuracy. This invention utilizes a single fan to simultaneously achieve the negative pressure required for adsorption and the positive pressure required for seed delivery assistance, simplifying the overall structure and reducing manufacturing costs and energy consumption. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the seed metering device provided by the present invention.

[0026] Figure 2 This is an exploded view of the seed metering device provided by the present invention.

[0027] Figure 3 This is a cross-sectional view of the seed metering device provided by the present invention.

[0028] Figure 4 This is an exploded view of the connection structure of the driving component, seed metering disc, and negative pressure cover provided by the present invention.

[0029] Figure 5 This is a partial structural schematic diagram of the seed metering device provided by the present invention.

[0030] Figure 6 This is a schematic diagram of the internal structure of the seed dispensing chamber provided by the present invention.

[0031] Figure 7 This is one of the structural schematic diagrams of the guide tube provided by the present invention.

[0032] Figure 8 This invention provides Figure 7 Cross-sectional view of the guide tube.

[0033] Figure 9 This is the second schematic diagram of the guide tube provided by the present invention.

[0034] Figure 10 This is a schematic diagram of the structure of a seeding system with a seed metering device provided by the present invention.

[0035] Figure 11 This is a schematic diagram of the structure of the seeding system with multiple seed metering devices provided by the present invention.

[0036] Figure 12 This is a flowchart illustrating the sowing method provided by the present invention.

[0037] Figure label: 100. Seeding device; 110. Shell; 111. First shell; 112. Second shell; 114. Seed discharging chamber; 1141. Seed filling area; 1142. Seed cleaning area; 1143. Seed unloading area; 115. Negative pressure chamber; 1151. Rotating negative pressure chamber; 1152. Fixed negative pressure chamber; 116. Air inlet; 117. Air outlet; 118. Seed discharge port; 120. Seed discharging tray; 121. Adsorption hole; 22. Fixing hole; 130. Driving component; 140. Air-blocking component; 150. Seed guide tube; 151. Conveying tube; 152. Guide tube; 1521. First inner wall surface; 1522. Second inner wall surface; 1523. Third inner wall surface; 1524. Fourth inner wall surface; 1525. Fifth inner wall surface; 160. Rotary seal; 170. Negative pressure cover; 171. Through hole; 172. Fixing part; 200. Fan; 210. Import; 220. Export; 300. Positive pressure piping assembly; 310. Positive pressure pipe; 320. Inlet pipe; 400. Negative pressure piping assembly; 410. Negative pressure pipe; 420. Vent pipe; 500, Seed Pressing Components. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0039] The specific terms used in this specification are for illustrative purposes only and are not intended to limit the illustrated embodiments. For example, expressions such as "same" and "identical" not only indicate a strictly identical state, but also indicate a state with tolerances or differences in the degree of functionality. For example, expressions indicating relative or absolute arrangement such as "in a certain direction," "along a certain direction," "side by side," "perpendicular," "centered on," "concentric," or "coaxial" not only strictly indicate such an arrangement, but also indicate a state of relative displacement by tolerances or angles or distances with the same degree of functionality.

[0040] The terms “center,” “longitudinal,” “lateral,” “length,” “width,” “thickness,” “upper,” “lower,” “front,” “rear,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inner,” “outer,” “clockwise,” “counterclockwise,” “axial,” “radial,” and “circumferential” indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.

[0041] Furthermore, features specified as "first" or "second" may explicitly or implicitly include one or more of those features. In the description of this invention, unless otherwise stated, "multiple" means two or more. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly specified. In the description of the embodiments of this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, B1 and / or B2 can represent: B1 existing alone, B1 and B2 existing simultaneously, and B2 existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0042] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0043] The following disclosure provides numerous different embodiments or examples for implementing various structures of the invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the invention. Furthermore, reference numerals and / or letters may be repeated in different examples. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. Additionally, examples of various specific processes and materials are provided, but those skilled in the art will recognize the applicability of other processes and / or the use of other materials.

[0044] The following is combined Figures 1-12 The seed metering device 100, seeding system and seeding method of the present invention are described.

[0045] The seed metering device 100 provided in this embodiment of the invention includes: a housing 110, a seed metering disc 120, a driving component 130, an air-blocking component 140, and a seed guide tube 150. The housing 110 has a receiving cavity, an air inlet 116, an air outlet 117, and a seed release port 118. The air inlet 116 is connected to the outlet 220 of a blower 200, the air outlet 117 is connected to the inlet 210 of the same blower 200, and the seed release port 118 is connected to a seed box. The seed metering disc 120 is disposed within the receiving cavity, dividing the receiving cavity into a seed metering chamber 114 located on one side of the seed metering disc 120 and a negative pressure chamber 115 located on the other side of the seed metering disc 120. Both the air inlet 116 and the seed release port 118 are connected to the seed metering chamber 114, and the air outlet 117 is connected to the negative pressure chamber 115. The seed metering disc 120 has multiple adsorption holes 121 penetrating the disc surface, each adsorption hole 121 connecting the seed metering chamber 114 and the negative pressure chamber 115. A driving component 130 is connected to the seed metering disc 120 and drives the seed metering disc 120 to rotate around its own axis. An air-blocking component 140 is fixedly installed in the housing 110, located within the negative pressure chamber 115. The air-blocking component 140 blocks the communication path between any adsorption hole 121 and the negative pressure chamber 115 when the adsorption hole moves to the seed unloading area. A seed guide tube 150 passes through the housing 110, extending at least partially into the seed metering chamber 114. The inlet of the seed guide tube 150 is located below the corresponding position of the air-blocking component 140 and is positioned close to the movement trajectory of the adsorption hole 121.

[0046] The fan outlet supplies positive pressure airflow to the seed discharge chamber through the air inlet, while the inlet of the same fan draws negative pressure into the negative pressure chamber through the air outlet, creating a pressure difference between the two sides of the adsorption hole, pointing from the seed discharge chamber to the negative pressure chamber. When the adsorption hole moves to the seed unloading area and is blocked by the air-blocking device, the connection between the adsorption hole and the negative pressure chamber is cut off, and the positive pressure airflow in the seed discharge chamber blows the seeds away from the adsorption hole and sends them into the seed guide tube.

[0047] refer to Figure 1 and Figure 2 The housing 110 has an internal cavity for accommodating the seed metering tray 120 and other components. The housing 110 can be designed as a split structure according to processing and assembly needs, for example, including a first housing 111 and a second housing 112 that are detachably connected (such as bolted or snap-fit ​​connections) to facilitate the installation, maintenance and cleaning of the internal seed metering tray 120.

[0048] The shell 110 has an air inlet 116, an air outlet 117, and a seed outlet 118 on its wall. The air inlet 116 is connected to the outlet 220 of an external fan 200 via a pipe to introduce positive pressure airflow into the shell 110. The air outlet 117 is connected to the inlet 210 of the same fan 200 via a pipe to evacuate air from the shell 110, creating a negative pressure environment. This configuration allows a single fan 200 to provide both positive and negative pressure air sources simultaneously, eliminating the need for two separate fan 200 systems, resulting in a compact structure and reduced energy consumption. The seed outlet 118 is located on the top or upper side of the shell 110 and connects to the seed outlet of an external seed box, allowing seeds in the seed box to be continuously fed into the receiving cavity by their own weight or an auxiliary seed delivery mechanism.

[0049] The seed metering disc 120 is a disc-shaped component that is rotatably mounted within the receiving cavity. The seed metering disc 120 divides the receiving cavity into two independent chambers along its axial or radial direction; that is, with the seed metering disc 120 as the boundary, the space on one side of the seed metering disc 120 forms the seed metering cavity 114, and the space on the other side forms the negative pressure cavity 115. Both the air inlet 116 and the seed outlet 118 are located on the wall of the housing 110 corresponding to the seed metering cavity 114, and both communicate with the seed metering cavity 114. The air outlet 117 is located on the wall of the housing 110 corresponding to the negative pressure cavity 115, and communicates with the negative pressure cavity 115. Through this structural layout, a positive pressure environment is maintained within the seed metering cavity 114, while a negative pressure environment is maintained within the negative pressure cavity 115.

[0050] The seed metering disc 120 has multiple adsorption holes 121 penetrating the disc surface. A directional, enhanced pressure difference is formed on both sides of the adsorption hole 121, pointing from the seed metering chamber 114 to the negative pressure chamber 115. Each adsorption hole 121 connects the seed metering chamber 114 and the negative pressure chamber 115. The positive pressure of the seed metering chamber 114 and the negative pressure of the negative pressure chamber 115 work synergistically, significantly increasing the adsorption force generated at the adsorption hole 121. This is particularly suitable for irregularly shaped or lightweight seeds.

[0051] In one embodiment, a plurality of adsorption holes 121 are arranged at intervals along the circumference of the seed metering disc 120, forming a ring of adsorption holes 121 concentrically arranged with respect to the seed metering disc 120. In some embodiments, the plurality of adsorption holes 121 are arranged at equal intervals along the circumference of the adsorption disc, and the circumferential distance between two adjacent adsorption holes 121 is the plant spacing. In some embodiments, the plurality of adsorption holes 121 are located on the outer edge of the seed metering disc 120. It should be noted that the pore size of the adsorption holes 121 is adapted to the average particle size of the seeds to be sown, so as to ensure that the air inlet end of the adsorption hole 121 can be blocked when the seeds are adsorbed, thereby generating a sufficient adsorption pressure difference, while preventing the seeds from being sucked into the negative pressure chamber 115 due to their small particle size.

[0052] The drive component 130 is fixedly mounted on the outer wall of the housing 110. The drive shaft of the drive component 130 passes through the housing 110 and extends into the receiving cavity, and is connected to the center of the seed metering disc 120. In one embodiment, the seed metering disc 120 is fixedly connected to the drive shaft of the drive component 130 through a hexagonal central hole. The drive component 130 is used to drive the seed metering disc 120 to rotate uniformly around its own central axis at a set speed. Preferably, the drive component 130 is a servo motor or a stepper motor, so that the rotation speed of the seed metering disc 120 can be precisely adjusted by the controller, thereby achieving precise plant spacing control in conjunction with the traveling speed of the seeder.

[0053] The air-blocking component 140 is fixedly mounted on the housing 110 and located inside the negative pressure chamber 115. The air-blocking component 140 can be made of a wear-resistant metal block (such as cast iron or powder metallurgy) or a high-strength engineering plastic block (such as polytetrafluoroethylene or nylon). In one embodiment, the surface of the air-blocking component 140 facing the seed metering disc 120 is a contact plane, which is in close contact with the surface of the seed metering disc 120. It should be noted that when the seed metering disc 120 rotates, the air-blocking component 140 does not rotate.

[0054] When the driving component 130 drives the seed metering disc 120 to rotate at a constant speed, each adsorption hole 121 rotating with the seed metering disc 120 will sequentially pass the position of the air blocking component 140. When any adsorption hole 121 moves to the seed unloading area, the air blocking component 140 blocks the adsorption hole 121. Since the air blocking component 140 completely blocks the air passage of the adsorption hole 121 from the negative pressure chamber 115 side, the gas flow path between the adsorption hole 121 and the negative pressure chamber 115 and the air outlet 117 is cut off, and the negative pressure suction disappears instantly. At the same time, since there is a continuous positive pressure airflow in the seed metering chamber 114, the positive pressure airflow passes through the inner hole of the adsorption hole 121 and applies a downward blowing force to the seeds adsorbed at the outer end of the hole. Under the action of its own gravity, positive pressure blowing force and centrifugal force, the seeds detach from the seed metering disc 120.

[0055] The upper part of the seed guide tube 150 can be welded to the housing 110. The seed guide tube 150 is at least partially inserted through the wall of the housing 110 and located inside the seed dispensing chamber 114. The seed guide tube 150 is a tubular structure. Specifically, the inlet of the seed guide tube 150 is positioned upwards, and the inlet end on the seed dispensing tray 120 is located exactly below the projected position of the air-blocking member 140 on the seed dispensing tray 120, for receiving seeds released by positive pressure from the adsorption hole 121. It should be noted that the inlet of the seed guide tube 150 is positioned close to the movement trajectory of the adsorption hole 121. The lower end of the seed guide tube 150 is located outside the housing 110, for guiding and delivering the received seeds to the seed furrow or inoculation container below.

[0056] refer to Figure 3During the operation of the seed metering device 100, after the fan 200 and drive component 130 are started, the outlet 220 of the fan 200 generates a positive pressure airflow, which enters the seed metering chamber 114 through the air inlet 116. A negative pressure suction is generated at the inlet 210, which evacuates the negative pressure chamber 115 through the air outlet 117. Thus, the seed metering chamber 114 maintains a positive pressure state, and the negative pressure chamber 115 maintains a negative pressure state. Seeds enter the seed metering chamber 114 through the seed release port 118 and, under the action of gravity, gather in the seed filling area 1141 near the seed metering disc 120. The drive component 130 drives the seed metering disc 120 to rotate. The adsorption holes 121 of the seed metering disc 120 sequentially pass through the seed filling area 1141. Under the action of pressure difference, the seeds are firmly adsorbed into the corresponding adsorption holes 121, and with the rotation of the seed metering disc 120, each adsorption hole 121 adsorbs seeds. When the seed-adsorbing hole 121 rotates with the seed-discharging disc 120 to the seed-unloading area, i.e., the location of the air-blocking element 140, the air-blocking element 140 blocks the seed-adsorbing hole 121. The seed-adsorbing hole 121 is blocked from the negative pressure chamber 115 by the air-blocking element 140, and the connection between the seed-adsorbing hole 121 and the negative pressure chamber 115 is cut off, and the adsorption force disappears. At the same time, the positive pressure airflow in the seed-discharging chamber 114 continues to act on the seed-adsorbing hole 121, applying a downward blowing force to the seed. Combined with the seed's own gravity and centrifugal force, the seed quickly detaches from the seed-adsorbing hole 121. After detachment, the seed falls downward under the action of gravity and falls precisely into the inlet of the seed guide tube 150 located directly below. It is then guided out of the shell 110 by the seed guide tube 150, completing a precise seed-discharging operation.

[0057] The seed metering device 100 provided by this invention divides the receiving cavity into a seed metering cavity 114 and a negative pressure cavity 115 through a seed metering disc 120. Positive pressure is generated by connecting the outlet 220 of the same fan 200 to the seed metering cavity 114, and negative pressure is generated by connecting the inlet 210 of the fan 200 to the negative pressure cavity 115. This creates a superimposed force with the same direction at the same adsorption point, significantly increasing the effective adsorption pressure difference at the adsorption hole 121. Compared to traditional solutions where only one side of the adsorption hole 121 is connected to negative pressure while the other side is exposed to normal or atmospheric pressure, the net adsorption force is significantly improved, enhancing the reliability of seed adsorption, effectively reducing the missed seeding rate, and adapting to higher operating speeds. When the adsorption hole 121 moves to the seed unloading area and is blocked by the air-blocking component 140, losing its negative pressure adsorption, the continuous positive pressure airflow in the seed discharge chamber 114 directly acts on the seeds, applying a downward active blowing force to the seeds. Combined with the seeds' own gravity and centrifugal force, the seeds quickly detach from the adsorption hole 121. The seed guide tube 150 is located directly below the corresponding position of the air-blocking component 140. While blowing down the seeds, the positive pressure airflow provides directional airflow guidance for the seeds' descent, allowing the seeds to fall accurately into the inlet of the seed guide tube 150 along a predetermined trajectory, shortening the seed delivery path, reducing interference during seed transfer, and improving sowing accuracy. This invention utilizes the positive pressure outlet 220 of a single fan 200 to supply air to the seed discharge chamber 114 and the negative pressure inlet 210 of the fan 200 to supply air to the negative pressure chamber 115. This simultaneously achieves the negative pressure required for adsorption and the positive pressure required for seed delivery assistance, simplifying the overall structure and reducing manufacturing costs and energy consumption.

[0058] In some embodiments, a first regulating valve is provided between the air inlet 116 and the outlet 220 of the fan 200 to regulate the positive pressure intensity in the seed dispensing chamber 114. A second regulating valve is provided between the air outlet 117 and the inlet 210 of the same fan 200 to regulate the negative pressure intensity in the negative pressure chamber 115. This embodiment of the invention achieves precise differential pressure control by controlling the positive and negative pressure intensities, making it suitable for sowing different varieties and sizes of seeds.

[0059] The seed metering device provided in this embodiment of the invention further includes a negative pressure cover 170, which is disposed within a negative pressure cavity 115, covers the seed metering disc 120, and is fixedly connected to the seed metering disc 120. The seed metering disc 120 and the negative pressure cover 170 form a rotating negative pressure cavity 1151. The negative pressure cover 170 communicates with an air outlet 117 through a rotating seal 160, so that the rotating negative pressure cavity 1151 maintains a negative pressure state when rotating with the seed metering disc 120. A fixed negative pressure cavity 1152 is formed between the side of the negative pressure cover 170 away from the seed metering disc 120 and the housing 110.

[0060] The negative pressure cover 170 has an overall cover-like structure and is disposed inside the negative pressure chamber 115. The negative pressure cover 170 covers the surface of the seed metering tray 120 facing the negative pressure chamber 115 and is fixedly connected to the seed metering tray 120. The negative pressure cover 170 and the surface of the seed metering tray 120 enclose a relatively sealed space, namely the rotating negative pressure chamber 1151. The side of the negative pressure cover 170 away from the seed metering tray 120 maintains a certain distance from the housing 110, and the space between the two constitutes the fixed negative pressure chamber 1152. The fixed negative pressure chamber 1152 does not change its spatial position with the rotation of the seed metering tray 120 and always remains stationary.

[0061] like Figure 4 As shown, in some embodiments, the seed metering disc 120 has fixing holes 122 on its outer periphery, and the negative pressure cover 170 has corresponding fixing parts 172. The fixing parts 172 are inserted into the fixing holes 122 to achieve a rigid connection, ensuring that the negative pressure cover 170 and the seed metering disc 120 rotate synchronously without relative sliding. In some embodiments, the fixing holes 122 are non-circular fixing holes, such as rectangular holes. There can be multiple fixing holes 122 and fixing parts 172, such as 4-6, for example, 4, 5, or 6; so that the negative pressure cover 170 and the seed metering disc 120 rotate synchronously without sliding friction. In one embodiment, multiple fixing holes 122 are arranged at intervals along the circumference of the seed metering disc 120, and fixing parts 172 are arranged at intervals along the circumference of the negative pressure cover 170, with one-to-one correspondence between them.

[0062] refer to Figure 2 and Figure 5 The negative pressure cover 170 has a through hole 171 extending through the wall thickness. This through hole 171 is preferably located at the center of the negative pressure cover 170, coaxial with the rotation axis of the seed metering disc 120, to maintain the stability of the airflow channel during rotation. The inner wall of the housing 110 has an integrally formed or fixedly mounted protrusion extending towards the negative pressure cover 170. Inside the protrusion is an air outlet 117 penetrating the housing, for communication with the inlet of the blower 200. The outer diameter of the protrusion matches the inner diameter of the through hole 171. The protrusion is axially inserted into the through hole 171, allowing the negative pressure cover 170 to be rotatably fitted onto the outer wall of the protrusion. The negative pressure suction generated by the inlet 210 of the blower 200 is transmitted through the second air outlet to the internal channel of the protrusion, and then through the through hole 171 to the rotating negative pressure chamber 1151 inside the negative pressure cover 170.

[0063] In some embodiments, the negative pressure cover 170 is rotatably connected to the outer wall surface of the protrusion via a rotary seal 160. The rotary seal 160 is fixed to the outer wall surface of the protrusion, and the inner wall surface of the through hole 171 is rotatably connected to the rotary seal 160. In one embodiment, the rotary seal 160 may be a bearing assembly, such as a deep groove ball bearing or a sliding bearing, rotatably supported on the outer wall surface of the protrusion to ensure the coaxiality and rotational smoothness of the negative pressure cover 170 when rotating with the seeding disc 120.

[0064] When the driving component 130 drives the seed metering disc 120 to rotate around its own axis, the negative pressure cover 170 rotates synchronously with the seed metering disc 120, and the gas in the rotating negative pressure chamber 1151 rotates as a whole, ensuring a negative pressure state within the rotating negative pressure chamber 1151. In this invention, rotational friction is formed between the negative pressure cover 170 and the housing 110. Compared with the sliding friction between the traditional seed metering disc 120 and the first housing 111, this reduces motion resistance, mechanical wear, and power consumption, thereby improving the overall transmission efficiency and extending the service life of key components.

[0065] refer to Figure 2 The first housing 111 and the second housing 112 are mated together and fixedly connected by fasteners, forming a receiving cavity. Sealing gaskets or sealant are applied to the mating surfaces of the first housing 111 and the second housing 112 to ensure the airtightness of the receiving cavity and prevent positive or negative pressure gas from leaking from the joint of the housing 110. In one embodiment, an air outlet 117 is provided on the second housing 112, and a fixed negative pressure cavity 1152 is formed between the negative pressure cover 170 and the second housing 112.

[0066] In some embodiments of the present invention, the seed guide tube 150 is disposed perpendicular to the ground in the housing 110. The seed metering tray 120 has a tray surface for adsorbing seeds. The tray surface of the seed metering tray 120 is disposed at an angle relative to the central axis of the seed guide tube 150, such as... Figure 1 and Figure 10 As shown. Specifically, there is an angle A between the central axis of the seed guide tube 150 and the disk surface, and angle A is an acute angle. After the seeds leave the adsorption hole 121, their initial falling direction under the action of gravity is basically consistent with the axial direction of the seed guide tube 150, so that the seeds can fall directly and accurately into the inlet of the seed guide tube 150 without bouncing, rolling, getting stuck, or hitting the tube wall at the inlet. This improves the seed guiding accuracy and operational reliability, thereby achieving a continuous and smooth connection between the seed metering and seed guiding processes, which is suitable for high-speed and high-frequency seed metering operations.

[0067] In some embodiments, 10° ≤ A ≤ 20°. Optionally, A can be 10°, 15°, 20°, etc. Preferably, A is 15°.

[0068] In some embodiments of the present invention, the inlet 210 end of the seed guide tube 150 is provided with an avoidance surface on the side near the seed metering tray 120 to prevent interference between the seed guide tube 150 and the seed metering tray 120. Furthermore, there is a gap D between the avoidance surface and the tray surface in the seed metering tray 120, and the gap D is smaller than the minimum size of the seed to prevent the seed from falling off at this gap.

[0069] In some embodiments, the clearance surface is parallel to the surface of the seeding disc 120, and 0.5mm ≤ D ≤ 2mm. Optionally, D can be 0.5mm, 0.6mm, 0.8mm, 1.0mm, 1.5mm, 2mm, etc. Preferably 1.5mm.

[0070] The inlet center of the seed delivery tube 150 is aligned with the trajectory path of the adsorption hole 121 on the seed metering disc 120. When the seed metering disc 120 rotates to the seed unloading area 1143, the seeds that have detached from the adsorption hole 121 are propelled by the continuously acting micro-positive pressure airflow and enter the inlet of the seed delivery tube 150 almost directly with a very small falling distance, achieving near-zero distance seeding and optimizing the seed delivery path.

[0071] refer to Figure 10 In this embodiment of the invention, the seed guide tube 150 includes a delivery tube 151 and a guide tube 152 that are interconnected. The inlet 210 of the delivery tube 151 passes through the housing 110 and is located in the seed dispensing chamber 114, for receiving seeds released from the adsorption holes 121 of the seed dispensing tray 120. The outlet of the guide tube 152 is used to guide the seeds out and place them into the seed furrow or inoculation container below. In some embodiments, the delivery tube 151 and the guide tube 152 are integrally formed. The guide tube 152 is configured to guide and regulate the flow of passing seeds, and the cross-section of the guide tube 152 gradually changes along the flow direction to reduce the dispersion of seed emission velocity and angle. In some embodiments, the inlet 210 of the guide tube 152 is circular or approximately circular to facilitate smooth seed introduction.

[0072] like Figure 7 and Figure 8 As shown, in some embodiments, the guide tube 152 is an arc-shaped tube. The inner wall surface of the guide tube 152 includes a first inner wall surface 1521 and a second inner wall surface 1522, which are sequentially connected to form a tube with openings at both ends. The first inner wall surface 1521 is located above the second inner wall surface 1522, and the lower end of the first inner wall surface 1521 is connected to the upper end of the second inner wall surface 1522. The two form a smooth transition at the connection point, for example, through a rounded chamfer or spline curve transition, to avoid forming steps or sharp corners at the connection point and prevent seeds from colliding or getting stuck during the fall.

[0073] Furthermore, the radius of curvature of the first inner wall surface 1521 is larger than that of the second inner wall surface 1522. The larger radius of curvature of the first inner wall surface 1521 is used to gently guide and initially decelerate the seeds and accompanying airflow, thus buffering and stabilizing the flow. The first inner wall surface 1521 and the second inner wall surface 1522 are connected tangentially, and their radius of curvature is smaller than that of the first inner wall surface 1521. This is used to finally accelerate the seed flow and calibrate its ejection direction, allowing it to be ejected with a more consistent and concentrated motion.

[0074] The embodiments of the present invention enable the airflow to achieve a smooth transition when flowing through the guide tube 152, effectively suppressing the generation of eddies and reducing random collisions between the seeds and the tube wall, thereby ensuring the orderly movement and trajectory consistency of the seeds during the transportation process.

[0075] In one embodiment, the radius of curvature of the first inner wall surface 1521 is 9 mm and the radius of curvature of the second inner wall surface 1522 is 5 mm. In another embodiment, the radius of curvature of the first inner wall surface 1521 is 9 mm and the radius of curvature of the second inner wall surface 1522 is 6 mm. In yet another embodiment, the radius of curvature of the first inner wall surface 1521 is 9 mm and the radius of curvature of the second inner wall surface 1522 is 7 mm.

[0076] In some embodiments of the present invention, along the flow direction, the top inner wall and / or bottom inner wall of the guide tube 152 gradually converge towards the central axis of the guide tube 152, causing the cross-sectional shape of the guide tube 152 to evolve into a V-shape or U-shape. Through the gradual change in cross-section from the circular inlet 210 to the V-shaped / U-shaped outlet, the entire process of seed flow from smooth entry to controlled exit is constrained. The V-shaped or U-shaped structure maintained at the outlet of the guide tube 152 can continue to maintain the seed aggregation state, thereby significantly improving the consistency and concentration of the seed flow exit direction, reducing energy loss and trajectory deviation caused by collisions with the tube wall, and ultimately improving the reliability, uniformity, and operational efficiency of seed delivery.

[0077] In some embodiments of the present invention, the inner wall surface of the guide tube 152 includes a third inner wall surface 1523, a fourth inner wall surface 1524, and a fifth inner wall surface 1525. The third inner wall surface 1523, the fourth inner wall surface 1524, and the fifth inner wall surface 1525 are sequentially connected to form a closed pipe with openings at both ends, and the third inner wall surface 1523 and the fifth inner wall surface 1525 are respectively disposed on both sides of the fourth inner wall surface 1524. The fourth inner wall surface 1524 is an arc surface, located above the third inner wall surface 1523 and the fifth inner wall surface 1525, and there is an included angle B between the third inner wall surface 1523 and the fifth inner wall surface 1525.

[0078] Specifically, the third inner wall surface 1523, the fourth inner wall surface 1524 and the fifth inner wall surface 1525 are connected end to end in the circumferential direction of the guide tube 152 to form a complete circumferential wall surface of the inner cavity of the guide tube 152. The first axial end (upper end) of the tube is connected to the end of the delivery tube 151, and the second axial end (lower end) is used as the outlet for discharging seeds.

[0079] refer to Figure 9 The fourth inner wall surface 1524 is located between the third inner wall surface 1523 and the fifth inner wall surface 1525—that is, along the circumference of the guide tube 152, the third inner wall surface 1523 and the fifth inner wall surface 1525 are located on both sides of the fourth inner wall surface 1524. For example, the fourth inner wall surface 1524 is located above the inner cavity of the guide tube 152, the third inner wall surface 1523 is located to its left, and the fifth inner wall surface 1525 is located to its right. The three are arranged around the circumference to form a complete tube cross section.

[0080] There is an included angle B between the third inner wall surface 1523 and the fifth inner wall surface 1525 in space. The included angle B is the angle between the tangent of the cross-sectional profile at any axial position of the guide tube 152 and the tangent of the cross-sectional profile at the position of the third inner wall surface 1523 and the position of the fifth inner wall surface 1525.

[0081] In some embodiments, 60°≤B≤120°. Optionally, B can be 60°, 75°, 90°, 105°, 120°, etc.

[0082] With the aid of a positive pressure airflow, the seeds in the delivery pipe 151 enter the guide pipe 152, where they are guided by the fourth inner wall surface 1524 (arc surface). The arc surface applies a continuous guiding force that gradually changes in the normal direction to the seeds, allowing them to achieve smooth movement direction adjustment in the initial stage of entering the guide pipe 152. This avoids impacts and rebounds caused by abrupt changes in the wall shape, thus ensuring a high degree of consistency in the initial movement state of all seeds within the guide pipe 152. The third inner wall surface 1523 and the fifth inner wall surface 1525 are located on both sides of the fourth inner wall surface 1524, and the guide pipe 152 gradually twists circumferentially along the seed flow direction in the axial direction. Throughout the process, the changes in velocity magnitude and direction are gradual, without any abrupt changes, resulting in seeds being ejected at a consistent speed and angle.

[0083] In some embodiments, a guide groove is provided at the connection between the third inner wall surface 1523 and the fifth inner wall surface 1525. The guide groove is provided along the extension direction of the guide tube 152. The guide groove can generate a continuous physical gathering and guiding effect on the passing seeds, effectively suppressing the lateral displacement, random jumping and posture rolling of the seeds in the bend, and forcing the seeds to move along a more consistent and stable predetermined trajectory.

[0084] refer to Figure 6 Along the rotation direction of the seed metering disc 120, such as clockwise, the seed metering chamber 114 includes a seed filling area 1141, a seed cleaning area 1142, and a seed unloading area 1143 connected in sequence. The seed filling area 1141 is located at the bottom, and the seed inlet 118 communicates with the seed filling area 1141. The seed cleaning area 1142 is equipped with a seed cleaning component, which uses the combined action of positive pressure airflow and the seed cleaning component to remove excess seeds from the adsorption hole 121, leaving only single seeds to ensure precise sowing per unit. The seed cleaning component includes seed cleaning teeth and a positive pressure airflow nozzle. As the seed metering disc 120 rotates, single seeds are stably conveyed to the seed unloading area 1143, where the seed guide tube 150 is located.

[0085] This invention also provides a seeding system, including a fan 200 and a seed metering device 100 as described in any of the above embodiments. The fan 200 has an inlet 210 for drawing in gas and an outlet 220 for discharging gas. The inlet 210 of the fan 200 is connected to an outlet 117 via a pipe to generate a negative pressure environment in a negative pressure chamber 115. The outlet 220 of the fan 200 is connected to an inlet 116 via a pipe to supply positive pressure airflow into a seed metering chamber 114. This simultaneously establishes pressure fields in opposite directions on both sides of the adsorption holes 121 of the seed metering disc 120, realizing the positive and negative pressure synergistic adsorption and airflow-assisted seed guiding functions described in the aforementioned embodiments. In one embodiment, the fan 200 is a centrifugal fan 200.

[0086] In some embodiments of the present invention, when the seeder has multiple seeding rows, such as 4 rows, 6 rows, 8 rows, etc., multiple seed metering devices 100 can be configured, with one seed metering device 100 corresponding to each seeding row. The seeding system also includes a positive pressure pipeline assembly 300 and a negative pressure pipeline assembly 400. The air outlet 117 of each seed metering device 100 is connected to the inlet 210 of the fan 200 through the negative pressure pipeline assembly 400, and the air inlet 116 of each seed metering device 100 is connected to the outlet 220 of the fan 200 through the positive pressure pipeline assembly 300. In the embodiments of the present invention, multiple seed metering devices 100 share the same fan 200, which can reduce costs.

[0087] refer to Figure 11 The positive pressure pipeline assembly 300 includes a positive pressure pipe 310 and multiple air inlet pipes 320. The inlet 210 of the positive pressure pipe 310 is connected to the outlet 220 of the fan 200. The inlet 210 of each air inlet pipe 320 is connected to the outlet of the positive pressure pipe 310. The air inlet 116 of each seeding device 100 is connected to the outlet of one air inlet pipe 320.

[0088] In this embodiment of the invention, the positive pressure airflow generated at the outlet 220 of the fan 200 is supplied to the seeding chamber 114 of each seeding device 100 through the positive pressure pipe 310 and multiple air inlet pipes 320, so that each seeding device 100 can obtain the required positive pressure airflow.

[0089] The negative pressure pipeline assembly 400 includes a negative pressure pipe 410 and multiple air outlet pipes 420. The outlet of the negative pressure pipe 410 is connected to the inlet 210 of the fan 200. The outlet of each air outlet pipe 420 is connected to the inlet 210 of the negative pressure pipe 410. The air outlet 117 of each seeding device 100 is connected to the inlet 210 of one air outlet pipe 420.

[0090] In this embodiment of the invention, the negative pressure suction generated at the inlet 210 of the fan 200 is transmitted to the negative pressure chamber 115 of each seeding device 100 through the negative pressure pipe 410 and multiple air outlet pipes 420, so that each seeding device 100 can obtain the required negative pressure suction force.

[0091] The seeding system provided in this embodiment of the invention further includes a frame and a seed pressing component 500. The fan 200, seed metering device 100, and seed pressing component 500 are all mounted on the frame. (Reference) Figure 11 The seed pressing component 500 is located downstream of the outlet of the seed guide tube 150 and is used to quickly fix the seeds and prevent them from bouncing. In one embodiment, the seed pressing component 500 is a hollow rubber wheel.

[0092] The seeding system provided in this embodiment of the invention also includes a seed box, the outlet of which is connected to the seed outlet 118 to continuously supply seeds to the seed filling area 1141.

[0093] This invention is applicable to the precision sowing of various arable seeds such as corn, soybean, and cotton, with different particle sizes and shapes, and has good versatility.

[0094] refer to Figure 12 The present invention also provides a sowing method based on the sowing system in any of the above embodiments, including: step 100, starting a fan to form a negative pressure environment in the negative pressure chamber and a positive pressure environment in the seed discharge chamber.

[0095] Specifically, after the fan starts, a continuous negative pressure suction is generated at the fan inlet, which is transmitted to the air outlet of the seed metering device. The air outlet is connected to the negative pressure chamber, and the negative pressure suction is transmitted into the negative pressure chamber, creating a negative pressure environment. At the same time, a continuous positive pressure airflow is generated at the fan outlet, which is transmitted to the air inlet. The air inlet is connected to the seed metering chamber, and a positive pressure environment is created within the seed metering chamber as the positive pressure airflow is transmitted.

[0096] The seed metering disc has an adsorption hole that runs through the disc surface. One side of the adsorption hole is connected to the seed metering chamber, and the other side is connected to the negative pressure chamber. Therefore, a directional enhanced pressure difference is formed on both sides of the adsorption hole, pointing from the seed metering chamber (positive pressure) to the negative pressure chamber (negative pressure).

[0097] Step 200: Drive the seed metering disc to rotate, and under the action of negative pressure, the seeds are adsorbed onto the adsorption holes.

[0098] Seeds enter the seed dispensing chamber through the seed inlet on the shell and gather near the surface of the seed dispensing disc under gravity. When the seed dispensing disc rotates to a point where an adsorption hole is near a seed in the seed dispensing chamber, a directional airflow and pressure difference are generated at the inner hole of that adsorption hole, pointing from the seed dispensing chamber to the negative pressure chamber. Under the action of this directional pressure difference, the seed near the adsorption hole is pushed towards the adsorption hole by the pressure difference force. At the same time, because the inner diameter of the adsorption hole is smaller than the seed particle size, the seed cannot pass through the adsorption hole into the negative pressure chamber and is instead blocked in the adsorption hole. Under the combined action of positive pressure thrust and negative pressure pull, the seed is firmly adsorbed onto the adsorption hole. As the seed dispensing disc continues to rotate, the adsorption hole containing a single seed carries the seed along the circumferential direction, entering the seed transport stage.

[0099] Step 300: When one of the adsorption holes rotates to the air-blocking element, under the action of positive pressure, the seeds in the adsorption hole detach from the seed metering plate and enter the seed guide tube, and are discharged from the shell.

[0100] When the seed-adsorbing hole rotates with the seed metering disc to the position of the air-blocking component, the air-blocking component completely seals the ventilated end face of the adsorption hole from the negative pressure chamber side. The gas flow path between the adsorption hole, the negative pressure chamber, and the air outlet is instantly cut off, and the negative pressure suction at the adsorption hole disappears. Simultaneously with the disappearance of the negative pressure suction, a positive pressure airflow continuously exists within the seed metering chamber. This positive pressure airflow passes through the inner hole of the adsorption hole, exerting a downward active blowing force on the seeds sealed at the outer end of the hole. Under the combined action of the blowing force of the positive pressure airflow and the seed's own gravity, the seed quickly detaches from the adsorption hole.

[0101] After the seeds detach from the adsorption pores, they move downwards along a predetermined trajectory under the continuous entrainment of the positive pressure airflow and the force of their own gravity. At this point, because the inlet of the seed guide tube is located directly below the projection position of the air-blocking element on the seed metering disc and precisely aligned with the seed release position, the seeds fall directly into the upper inlet of the seed guide tube. After entering the seed guide tube, the seeds are ejected from the outlet of the seed guide tube at a consistent speed and direction, and are finally discharged into the seed furrow or inoculation container, completing a precise seed metering operation.

[0102] As the seed metering disc continues to rotate, the adsorption hole that has already been seeded passes the area covered by the air-blocking component and is exposed to the negative pressure environment again, regaining its ability to adsorb seeds. Multiple adsorption holes on the seed metering disc sequentially pass through steps 200 and 300 above, achieving continuous seed adsorption, seed transport, and seed dispensing, thus completing a continuous precision seeding operation.

[0103] The rotation speed of the seed metering disc and the travel speed of the ground wheel of the seeder are synchronously matched and controlled by the controller, so that under the preset plant spacing conditions, the seeder travels a distance of one plant spacing for every one adsorption hole the seed metering disc rotates, thereby achieving precise sowing with uniform plant spacing.

[0104] When there are multiple seed metering devices, simultaneous operation of multiple seed metering devices can achieve synchronous sowing of multiple rows.

[0105] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A seed metering device, characterized in that, include: The housing has a receiving cavity, and the housing has an air inlet, an air outlet and a seed release port. The air inlet is used to communicate with the outlet of the fan, the air outlet is used to communicate with the inlet of the same fan, and the seed release port is used to communicate with the seed box. A seed metering tray is disposed within the receiving cavity, dividing the receiving cavity into a seed metering chamber located on one side of the seed metering tray and a negative pressure chamber located on the other side of the seed metering tray. The air inlet and the seed outlet are both connected to the seed metering chamber, and the air outlet is connected to the negative pressure chamber. The seed metering tray is provided with a plurality of adsorption holes penetrating its surface, and each adsorption hole is connected to the seed metering chamber and the negative pressure chamber. A driving component, which is connected to the seed metering disc, is used to drive the seed metering disc to rotate around its own axis; An air-blocking component is fixedly disposed in the housing and located in the negative pressure chamber. The air-blocking component is used to block the communication path between the adsorption hole and the negative pressure chamber when any of the adsorption holes moves to the seed unloading area. A seed guide tube is inserted through the housing and extends at least partially into the seed discharge chamber. The inlet of the seed guide tube is located below the corresponding position of the air blocking component and is set close to the movement trajectory of the adsorption hole. The fan outlet supplies positive pressure airflow to the seed discharge chamber through the air inlet, while the fan inlet draws negative pressure into the negative pressure chamber through the air outlet, creating a pressure difference between the adsorption holes and the negative pressure chamber. When the adsorption holes move to the seed unloading area and are blocked by the air-blocking component, the connection between the adsorption holes and the negative pressure chamber is cut off, and the positive pressure airflow in the seed discharge chamber blows the seeds away from the adsorption holes and sends them into the seed guide tube.

2. The seed metering device according to claim 1, characterized in that, It also includes a negative pressure cover, which is disposed inside the negative pressure cavity, covers the seed metering tray, and is fixedly connected to the seed metering tray. The negative pressure cover and the seed metering tray form a rotating negative pressure cavity. The negative pressure cover is connected to the air outlet through a rotating seal, so that the rotating negative pressure cavity maintains a negative pressure state when it rotates with the seed metering tray.

3. The seed metering device according to claim 1, characterized in that, The seed guide tube is installed in the housing in a direction perpendicular to the ground. The surface of the seed metering disc is inclined relative to the central axis of the seed guide tube. There is an angle A between the central axis of the seed guide tube and the disc surface, and the angle A is an acute angle.

4. The seed metering device according to claim 3, characterized in that, 10°≤A≤20°。 5. The seed metering device according to claim 1, characterized in that, The inlet end of the seed guide tube has an avoidance section on the side near the seed metering tray. There is a distance D between the avoidance section and the surface of the seed metering tray. The distance D is smaller than the minimum size of the seed.

6. The seed metering device according to claim 5, characterized in that, The avoidance section is parallel to the surface of the seeding disc, and 0.5mm≤D≤2mm.

7. The seed metering device according to claim 1, characterized in that, The seed guide tube includes a delivery tube and a guide tube that are interconnected. The inlet of the delivery tube passes through the shell and is located in the seed discharge chamber. The outlet of the guide tube is used to guide the seeds to flow out. The cross-section of the guide tube gradually changes along the flow direction.

8. The seed metering device according to claim 7, characterized in that, The inner wall of the guide tube includes a first inner wall surface and a second inner wall surface, which are sequentially connected to form a pipe with openings at both ends; the radius of curvature of the first inner wall surface is greater than that of the second inner wall surface, and the first inner wall surface is located above the second inner wall surface.

9. The seed metering device according to claim 7, characterized in that, The inner wall surface of the guide tube includes a third inner wall surface, a fourth inner wall surface, and a fifth inner wall surface. The third inner wall surface, the fourth inner wall surface, and the fifth inner wall surface are connected in sequence to form a pipe with openings at both ends. The third inner wall surface and the fifth inner wall surface are respectively located on both sides of the fourth inner wall surface. The fourth inner wall surface is an arc surface and is located above the third inner wall surface and the fifth inner wall surface. There is an included angle B between the third inner wall surface and the fifth inner wall surface.

10. The seed metering device according to claim 9, characterized in that, 60°≤B≤120°。 11. The seed metering device according to claim 1, characterized in that, Along the rotation direction of the seed metering disc, the seed metering chamber includes a seed filling area, a seed cleaning area and a seed unloading area connected in sequence, wherein the seed filling area is located at the bottom, the seed cleaning area is provided with a seed cleaning component, and the seed guide tube is located in the seed unloading area.

12. A seeding system, characterized in that, It includes a fan and a seed metering device as described in any one of claims 1 to 11, wherein the inlet of the fan is connected to the outlet, and the outlet of the fan is connected to the inlet.

13. The seeding system according to claim 12, characterized in that, The seeding device comprises multiple units, and the seeding system further includes a positive pressure pipeline assembly and a negative pressure pipeline assembly. The air outlet of each seeding device is connected to the inlet of the fan through the negative pressure pipeline assembly, and the air inlet of each seeding device is connected to the outlet of the fan through the positive pressure pipeline assembly.

14. The seeding system according to claim 13, characterized in that, The positive pressure pipeline assembly includes a positive pressure pipe and multiple air inlet pipes. The inlet of the positive pressure pipe is connected to the outlet of the fan. The inlet of each air inlet pipe is connected to the outlet of the positive pressure pipe. The air inlet of each seed metering device is connected to the outlet of one of the air inlet pipes. And / or, the negative pressure pipeline assembly includes a negative pressure pipe and a plurality of air outlet pipes, the outlet of the negative pressure pipeline is connected to the inlet of the fan, the outlet of each air outlet pipe is connected to the inlet of the negative pressure pipe, and the air outlet of each seeding device is connected to the inlet of one of the air outlet pipes.

15. The seeding system according to claim 12, characterized in that, It also includes a frame and a seed pressing component. The fan, the seed metering device and the seed pressing component are all located on the frame, and the seed pressing component is located downstream of the seed guide pipe outlet.

16. A sowing method, based on the sowing system as described in any one of claims 12 to 15, characterized in that, include: Start the fan to create a negative pressure environment in the negative pressure chamber and a positive pressure environment in the seed dispensing chamber; The seed metering disc is driven to rotate, and under the action of negative pressure, the seeds are adsorbed onto the adsorption holes; When the adsorption hole rotates to the air-blocking element, under the action of positive pressure, the seeds in the adsorption hole detach from the seed metering plate and enter the seed guide tube, and are discharged from the shell.

Images