Small seed quantity metering device, seeding disc and centrifugal seeding method

Abstract

A small-seed-volume seeding device, its seeding disc, and a centrifugal seeding method. The small-seed-volume seeding device includes a seeding disc, which includes: a fixed disc mounted on the seeding device base and forming a vacuum negative pressure chamber therewith; spiral grooves are provided on the fixed disc corresponding to the seed filling area, seed cleaning area, seed carrying area, and seed dropping area, with the spiral groove at one end of the seed filling area being close to the center of the fixed disc, and the spiral groove at one end of the seed dropping area being away from the center of the fixed disc and correspondingly provided with a seed dropping pressure relief groove; the spiral grooves are connected to the vacuum negative pressure chamber; a drive block is mounted on a drive shaft that passes through the fixed disc and is connected to the seeding device base; and a movable disc is mounted on the drive block adjacent to the fixed disc and driven by the drive block to rotate relative to the fixed disc; a plurality of radial grooves are evenly distributed along the circumference of the movable disc, and each radial groove forms an independent suction hole at the intersection with the spiral groove; when the movable disc rotates, the suction hole moves along the radial grooves from the proximal end to the distal end along the spiral grooves to complete sowing and seed cleaning. The present invention also provides a centrifugal seeding method.

Description

Technical Field

[0001] The invention relates to a sowing technology of an air-suction type seed meter, in particular to a small-seeding quantity seed meter suitable for sowing in breeding test plots, a combined seeding disc and a centrifugal seeding method. Background Art

[0002] In breeding trials, it's difficult to balance both reseeding and missed seeding rates, as the amount of seeds sown at a time is relatively small and the shapes and sizes of parent seeds vary greatly. The circular suction holes used in existing air-suction seed meters can easily lead to the reabsorption of small seeds while ensuring the stability of adsorption of large seeds. Therefore, circular suction holes are less versatile for different seed varieties with widely varying shapes and sizes. Furthermore, the rotation radius of the suction holes in the evenly distributed seed tray is equal, meaning the linear velocity of the suction holes when capturing seeds within the population is the same as when dropping seeds. When sowing small amounts of seeds in breeding trials, the suction holes move too quickly within the population, resulting in too short a contact time with the population, which increases the missed seeding rate (especially in the later stages of plot sowing, when there are fewer seeds remaining in the seed cavity). Furthermore, the existing seed cleaning mechanism works by invading the suction hole area, reducing its adsorption capacity and forcibly scraping off reabsorbed seeds. The degree of intrusion into the suction holes can be adjusted to accommodate differences in seed size and shape across different seed varieties. Therefore, the mechanical adjustment method used by the existing seed cleaning mechanism is not compatible with the differences in seed morphology, resulting in the existing field sowing equipment being unable to meet the requirements of multiple varieties, small seed quantities, low reseeding rate and missed seeding rate in breeding experiments.

[0003] Existing air-suction seed trays mostly feature circular suction holes, which are less adaptable to the varying shapes and sizes of seeds from different varieties. Because seeds vary greatly in shape and size, circular suction holes, while ensuring stable suction of large seeds, can easily cause re-absorption of small seeds. Reducing the pressure or reducing the area of ​​the suction holes can prevent the capture of large seeds, especially seeds with distinct edges, such as corn, which are particularly prone to re-absorption. Seed trays used for breeding trials (plot sowing) are often rotating circular discs with uniformly distributed suction holes. The rotation radius of the suction holes from the center of rotation on these discs remains constant, resulting in the same linear velocity of the suction holes as during seed placement. Because the number of seeds required for a single plot in breeding trials is relatively small, if the suction holes pass through the seed population at a high speed, the contact time between the suction holes and the seed population is too short, which can easily lead to seed capture failure (i.e., missed seeds). This is especially challenging in the final stages of sowing a plot, when only a dozen or so seeds remain in the seed cavity, making uniform seed placement even more challenging. Moreover, breeding trials have high requirements for the missed seeding rate. Therefore, in order to reduce missed seeding, the only way to do so is to reduce the sowing speed and increase the negative pressure, which seriously reduces the efficiency.

[0004] The existing seed cleaning method involves a cleaning mechanism invading the suction hole area to remove reabsorbed seeds. This method adapts to seed size differences between strains by adjusting the number of suction holes it penetrates. This method is not well suited for seed sowing operations where significant differences exist both within and between strains. Consequently, current breeding trial sowing (plot sowing) suffers from high rates of overseeding and missed seeding. Due to the specialized sowing requirements of breeding trial sowing (small population size, low missed seeding rate, large number of strains, and the inability to inter-plot inter-strain mixing), field sowing machinery is difficult to apply. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a small seed quantity metering device, a seeding disc and a centrifugal seeding method thereof in view of the above-mentioned defects of the prior art.

[0006] In order to achieve the above object, the present invention provides a seeding disc of a small seeding device, which is installed on a seeding device base and includes:

[0007] A fixed plate is mounted on the seed metering device base and forms a vacuum negative pressure chamber with the seed metering device base, the vacuum negative pressure chamber being connected to a negative pressure pump through a negative pressure channel; a spiral groove is provided on the fixed plate, the spiral groove being arranged in sections corresponding to the seed filling area, seed cleaning area, seed carrying area and seed dropping area of ​​the fixed plate, and the spiral groove located at one end of the seed filling area is close to the center of the fixed plate, and the spiral groove located at one end of the seed dropping area is away from the center of the fixed plate and is correspondingly provided with a seed dropping pressure relief groove; the spiral groove is communicated with the vacuum negative pressure chamber, and the airflow in the negative pressure channel can only be sucked in through the spiral groove;

[0008] A driving block is mounted on a driving shaft, wherein the driving shaft passes through the fixed plate and is connected to the seed metering device base; and

[0009] The movable disk is installed on the driving block adjacent to the fixed disk, and the driving block drives the movable disk to rotate relative to the fixed disk; a plurality of radial grooves are evenly distributed along the circumference of the movable disk, and each radial groove forms an independent suction hole at the intersection with the spiral groove; when the movable disk rotates, the suction hole moves along the radial groove from the proximal end to the distal end with the spiral groove to complete sowing and clearing.

[0010] In the seeding disk of the small seeding device, the seeding curve distribution angle of the spiral groove in the seeding area is α1, and -90°≤α1≤0°. The boundary distribution range of the flow field disturbance velocity gradient of the suction hole is calculated using the following formula:

[0011] ;

[0012] Among them, x, y, z are the values ​​of the spatial coordinate system OXYZ with the center of the suction hole as the origin, and the unit is mm; Kb is the width of the suction hole, in mm; K l is the length of the suction hole, in mm; P is the vacuum degree of the suction hole, in Pa; Y va Y is the long radius of the boundary domain of the airflow velocity gradient of the suction hole, in mm; vb Y is the radius of the boundary region of the airflow velocity gradient of the suction hole, in mm; vc is the short radius of the airflow velocity gradient boundary domain of the suction hole, in mm; the bottom of the seed filling area is located within the gradient domain boundary range of the suction hole at the starting point of the seed filling curve distribution.

[0013] In the seeding disc of the above-mentioned small seeding device, the seed clearing curve of the spiral groove located in the seed clearing area is an Archimedean spiral, and the movement trajectory of the seed is:

[0014] ;

[0015] Among them, R n is the seed gyration radius, in mm; a, b are constants; θ n is the helix angle, in degrees;

[0016] The seeds are centrifuged at a constant radial speed v in the seed cleaning area. r With constant angular velocity w a sports:

[0017] ;

[0018] in, ; c is a constant; R1 is the initial gyration radius, in mm; R2 is the tail gyration radius, in mm; the spiral distribution angle of the seed clearing curve is α2, and 0°≤α2≤90°.

[0019] The seeding disc of the small seeding device is provided with a seed cleaning tooth on the inner side of the radial groove. The seed cleaning tooth is a sawtooth tooth structure. The tooth connection line of the seed cleaning tooth is parallel to the tangent line of the Archimedean spiral at the intersection of the radial groove and the spiral groove. The tooth spacing L c Greater than the seed length; the midpoints of the tooth connection lines are located at intervals of L c On the equally spaced concentric circles, the number of teeth c n for:

[0020] .

[0021] In the seeding disk of the above-mentioned small seed quantity seeder, each pair of teeth of the seed cleaning teeth passes through the spiral groove in sequence during the seed movement process to change the adsorption force of the suction hole and adjust the seeds adsorbed on the suction hole.

[0022] The seeding disc of the small seeding device, wherein the radial grooves are evenly distributed radially outward from the center of the moving disc, and the distribution number k n for:

[0023] ;

[0024] Among them, V p is the forward speed of the seeder, in cm / s; L is the plant spacing, in cm; n s is the rotating disk speed, in r / s; , c is a constant.

[0025] In order to better achieve the above-mentioned object, the present invention further provides a centrifugal seeding method for a small-seed-volume seeding device, wherein the passage speed of the suction holes within the seed population is reduced by changing the rotation radius of the suction holes to improve seeding omission and seeding efficiency, comprising the following steps:

[0026] Use the above seeding disc and adjust the seeding device parameters according to the characteristics of the seeds to be sown;

[0027] The movable disc of the seeding disc is driven to rotate periodically relative to the fixed disc, and the suction holes capture the seeds to be sown from the seed filling area. The captured seeds to be sown are centrifugally moved along the spiral grooves of the fixed disc along with the suction holes, and sequentially pass through the seed filling area, the seed cleaning area, the seed carrying area and the seed dropping area;

[0028] Among them, after the sowing seeds enter the seed cleaning area, they gradually move away from the rotation center and the movement speed increases; the sawtooth-shaped teeth of the radial grooves sequentially remove the heavy seeds through the spiral grooves; after the sowing seeds enter the seed carrying area, they perform uniform circular motion, and the circular motion speed of the seeds v c for: , to enhance the seed holding stability and seed holding capacity of the suction hole; after the sowing seeds enter the sowing area, they are released by the suction hole under the action of the sowing pressure relief groove.

[0029] The centrifugal seeding method of the above-mentioned small seed quantity seeding device, wherein the characteristics of the seeds to be sown include physical properties and mechanical properties, the physical properties include the length, width, thickness, density, porosity, sphericity and moisture content of the seeds, and the mechanical properties include the rolling friction coefficient, sliding friction coefficient and stacking angle of the seeds.

[0030] The centrifugal seeding method of the above-mentioned small seed quantity seeding device, wherein the seeding device parameters include the seeding rotation radius, the seeding disk rotation speed, the number of suction holes of the seeding disk moving disk, the seeding disk vacuum degree and the width of the spiral groove of the seeding disk fixed disk.

[0031] In order to better achieve the above-mentioned purpose, the present invention also provides a small-seeding quantity seeding device, which includes the above-mentioned seeding disc and adopts the above-mentioned centrifugal seeding method for sowing.

[0032] The technical effects of the present invention are:

[0033] The suction holes of the seeding disk of the present invention are formed by combining the slot holes of the movable disk and the fixed disk, and integrate the functions of seed clearing and seed carrying trajectory restriction. The seed carrying movement trajectory is restricted by the slot holes of the fixed disk, and the slot holes of the movable disk actively rotate and drive the seeds to push the seeds to perform centrifugal motion; the seed carrying requirements in different functional areas are achieved by changing the radius size; and seed clearing is achieved with the help of the teeth; the fixed disk limits the seed carrying curve to achieve low-speed seed bagging near the rotation center of the seeding disk, that is, low-speed seed capture; variable-speed movement, that is, the rotation radius gradually increases and the linear speed gradually increases in the process of the seeds moving along the spiral line; the suction hole length is changed by the teeth, thereby changing the adsorption capacity of the suction hole, and the method of controlling the fluid is used instead of the seed cleaning mechanism to force seed clearing.

[0034] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments, but this does not limit the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a structural schematic diagram of a seed meter according to an embodiment of the present invention;

[0036] Figure 2 This is a front view of a seed metering device according to an embodiment of the present invention;

[0037] Figure 3 for Figure 2 Side view of;

[0038] Figure 4A This is a schematic diagram of the structure of a moving disk according to an embodiment of the present invention;

[0039] Figure 4B This is a schematic diagram of the structure of a moving disk according to another embodiment of the present invention;

[0040] Figure 5 This is a schematic diagram of a radial groove structure according to an embodiment of the present invention;

[0041] Figure 6 This is a schematic diagram of the fixed plate structure according to an embodiment of the present invention;

[0042] Figure 7 for Figure 6 Side view of;

[0043] Figure 8 FIG. 1 is a schematic diagram of the structure of a driving block according to an embodiment of the present invention.

[0044] Among them, the reference numerals

[0045] 1 Seeder base

[0046] 11 Anti-reverse installation structure

[0047] 12 Support structure

[0048] 13 Negative pressure channel

[0049] 14 Positioning seat

[0050] 15 External card slots

[0051] 2. Fixing

[0052] 21 Positioning mounting holes

[0053] 22 spiral grooves

[0054] 221 Initial spiral groove

[0055] 222 Second spiral groove

[0056] 223 The third spiral groove

[0057] 224 Final spiral groove

[0058] 23 Seeding pressure relief trough

[0059] 24 Pressure relief guide groove

[0060] 3 moving disk

[0061] 31 radial grooves

[0062] 311 Slot distal end seed holding structure

[0063] 312 tooth connection line

[0064] 313 Clearing Teeth

[0065] 32 Anti-reverse drive hole

[0066] 4 driver blocks

[0067] 41 Pallet chamfer

[0068] 42 card board body

[0069] 43 Card board anti-reverse installation structure

[0070] 44 drive hole

[0071] 5 drive shaft

[0072] k1-k7 suction holes

[0073] M population DETAILED DESCRIPTION

[0074] The structural principle and working principle of the present invention are described in detail below with reference to the accompanying drawings:

[0075] See also Figure 1-Figure 3 , Figure 1This is a structural diagram of a seed meter according to an embodiment of the present invention. Figure 2 This is a front view of a seed metering device according to an embodiment of the present invention. Figure 3 for Figure 2 Side view. The small-volume seed metering device of the present invention includes a seed metering device base 1 and a seeding disc mounted on the seed metering device base 1. The seeding disc is a modular seeding disc that uses a centrifugal seeding method for sowing. The composition, structure, relative positional relationships, connection relationships, and functions of the other parts of the small-volume seed metering device of the present invention are all relatively mature existing technologies and are not described in detail here. The following describes in detail only the seeding disc and seeding method of the present invention.

[0076] See also Figures 4A-8 , Figure 4A This is a schematic diagram of the structure of a moving disk according to an embodiment of the present invention. Figure 4B This is a schematic diagram of the structure of a moving disk according to another embodiment of the present invention. Figure 5 This is a schematic diagram of the radial groove structure according to an embodiment of the present invention. Figure 6 This is a structural diagram of the fixed plate 2 according to an embodiment of the present invention. Figure 7 for Figure 6 Side view of Figure 8 It is a schematic diagram of the structure of the driving block 4 of an embodiment of the present invention. The seeding disk of the present invention includes: a fixed disk 2, which is fixed on the seeding device base 1 through a positioning installation hole 21, and forms a vacuum negative pressure chamber between the fixed disk 2 and the seeding device base 1, and the vacuum negative pressure chamber is connected to the negative pressure pump through a negative pressure channel 13; the fixed disk 2 is preferably a disc structure, and a spiral groove 22 is provided on the disc surface of the disc, and a pressure relief guide groove 24 is provided on the side edge of the disc; the spiral groove 22 is provided in sections corresponding to the seed filling area, seed cleaning area, seed carrying area and seeding area of ​​the fixed disk 2, and the spiral groove 22 at one end of the seed filling area is close to the center of the fixed disk 2, and the spiral groove 22 at one end of the seeding area is away from the center of the fixed disk 2 and is correspondingly provided with a seeding pressure relief groove 23; the spiral groove 22 and the vacuum negative pressure chamber The air flow in the negative pressure channel 13 can only be sucked in through the spiral groove 22, that is, the spiral groove 22 is used to limit the seed carrying trajectory to ensure that the seeds move along the spiral groove 22 on the seeding disk; the driving block 4 is installed on the driving shaft 5, and the driving shaft 5 passes through the fixed disk 2 and is connected to the seeding device base 1; and the movable disk 3 is installed on the driving block 4 adjacent to the fixed disk 2, and the driving block 4 drives the movable disk 3 to rotate relative to the fixed disk 2; a plurality of radial grooves 31 are evenly distributed along the circumference of the movable disk 3, and each of the radial grooves 31 forms an independent suction hole kn at the intersection with the spiral groove 22; when the movable disk 3 rotates, the suction hole moves from the proximal end to the distal end along the radial groove 31 with the spiral groove 22 to complete sowing and seed cleaning.

[0077] See also Figure 6In this embodiment, the spiral groove 22 is located in the seed filling area, and the seed filling curve distribution angle is α1, and -90°≤α1≤0°. The flow field disturbance velocity gradient boundary distribution range of the suction hole is calculated using the following formula:

[0078] ;

[0079] Among them, x, y, z are the values ​​of the spatial coordinate system OXYZ with the center of the suction hole as the origin, and the unit is mm; K b is the width of the suction hole, in mm; K l is the length of the suction hole, in mm; P is the vacuum degree of the suction hole, in Pa; Y va Y is the long radius of the boundary domain of the airflow velocity gradient of the suction hole, in mm; vb Y is the radius of the boundary region of the airflow velocity gradient of the suction hole, in mm; vc is the short radius of the airflow velocity gradient boundary domain of the suction hole, in mm; the bottom of the seed filling area is located within the gradient domain boundary range of the suction hole at the starting point of the seed filling curve distribution.

[0080] The seed clearing curve of the spiral groove 22 in the seed clearing area is preferably an Archimedean spiral, and the movement trajectory of the seeds can be expressed by the following formula:

[0081] ;

[0082] Among them, R n is the seed gyration radius, in mm; a, b are constants; θ n is the helix angle, in degrees;

[0083] The seeds are centrifuged at a constant radial speed v in the seed cleaning area. r With constant angular velocity w a sports:

[0084] ;

[0085] in, ; c is a constant; R1 is the initial gyration radius, in mm; R2 is the tail gyration radius, in mm; the spiral distribution angle of the seed clearing curve is α2, and 0°≤α2≤90°.

[0086] See also Figure 5 In this embodiment, the radial groove 31 is provided with a slotted distal end seed holding structure 311 at one end away from the center of the circle. The slotted distal end seed holding structure 311 can be, for example, a U-shaped groove structure; a seed cleaning tooth 313 is further provided on the inner side of the radial groove 31, preferably a sawtooth tooth structure, and the tooth connection line 312 of the seed cleaning tooth 313 is parallel to the tangent of the Archimedean spiral at the intersection of the radial groove 31 and the spiral groove 22, and the tooth spacing L cGreater than the seed length; the midpoints of the tooth connection lines 312 are located at intervals of L c On the equally spaced concentric circles, the number of teeth c n for:

[0087] .

[0088] In the process of seed movement, each pair of teeth of the seed cleaning teeth 313 sequentially and laterally passes through the spiral groove 22 to change the adsorption force of the suction hole and adjust the seeds adsorbed on the suction hole.

[0089] In this embodiment, the radial grooves 31 are evenly distributed radially outward from the center of the moving disk 3, and the number of distribution is k. n for:

[0090] ;

[0091] Among them, V p is the forward speed of the seeder, in cm / s; L is the plant spacing, in cm; n s is the rotation speed of the moving disk 3, in r / s; , c is a constant.

[0092] In this embodiment, the seed meter base 1 is equipped with an anti-reverse installation structure 11, a negative pressure channel 13, a positioning seat 14 for the fixed disk 2, an external retaining groove 15 for the fixed disk 2, and multiple support structures 12. The structural configuration of the seed meter base 1 ensures the accurate installation and airtightness of the fixed disk 2, so that airflow in the negative pressure channel 13 can only flow into the spiral groove 22 of the fixed disk 2. The movable disk 3 has n radial grooves 31 evenly distributed around its circumference. The movable disk 3 and the fixed disk 2 have the same radius. When installed concentrically, the radial grooves 31 combine with the spiral grooves 22 on the fixed disk 2 to form a plurality of independent suction holes k1-k7. When the suction holes are filled with seeds, as the movable disk 3 rotates, the radial grooves 31 push the seeds along the spiral grooves 22 on the fixed disk 2 until they reach the seeding area. The center of the movable disk 3 is an anti-reverse drive hole 32, preferably a square hole with an anti-reverse installation structure. It is driven by the drive shaft 5, which can be connected to the seed meter base 1 via a bearing.

[0093] The spiral groove 22 of this embodiment is divided into four parts, consisting of four two-dimensional spiral lines, distributed about 270 degrees on the fixed disk 2, with one end close to the center of the circle and the other end away from the center of the circle. The initial spiral groove 221 is located in the seed filling area, that is, in the seed population M, for capturing seeds; the second spiral groove 222 is located in the seed clearing area, gradually moving away from the center, for increasing the rotation speed of the seeds; the third spiral groove 223 is a constant diameter arc, located in the seed carrying area, for allowing the seeds to move to the seeding point in a stable state, and the spiral distribution angle of the seed carrying curve is α3; the last spiral groove 224 is a seeding pressure relief groove 23, located in the seeding area, for allowing the seeds to escape from the suction hole. The second spiral groove 222 is set according to the Archimedean spiral, which is characterized by a constant radial velocity away from the center of the circle during the spiral process, which can make the centrifugal motion of the seeds more stable. A centrifugal migration curve other than the Archimedean spiral can also be set as needed. The last spiral groove 224 is a seeding pressure relief groove 23 that no longer penetrates the fixed plate 2, so as to isolate the pressure of the vacuum negative pressure chamber so that the seeds are no longer affected by the suction force of the suction hole, thereby achieving smooth separation.

[0094] The movable disk 3 is installed on the surface of the fixed disk 2 in an overlapping manner. Since the two disks are installed concentrically and rotate relative to each other, the slot holes of the multiple radial grooves 31 on the movable disk 3 and the slot holes of the spiral grooves 22 on the fixed disk 2 form a combination of suction holes k1-kn. When the movable disk 3 rotates, the suction holes move along the spiral grooves 22 on the fixed disk 2. As the spiral grooves 22 move from the proximal end to the distal end, the suction holes also move from the proximal end to the distal end. Therefore, the serrated teeth of the seed cleaning teeth 313 on the radial grooves 31 will pass through the slot holes of the spiral grooves 22 in sequence. When passing through the slot holes of the spiral grooves 22, the adsorption capacity of the suction holes will be changed, and additional force will be applied to the seeds adsorbed on the suction holes. The interlaced movement mainly occurs in the second section, so the tooth connection line 312 should be parallel to the tangent of the Archimedean spiral at the intersection of the two slot holes. The seed cleaning teeth 313 and the slot holes of the radial grooves 31 can be set in various forms, such as Figure 4B As shown, it can also be a U-shaped structure without tooth holes.

[0095] The movable disk 3 is driven by a drive block 4. The card body 42 of the drive block 4 can be a hexagonal shaft structure with a card chamfer 41 and a drive hole 44 at its center. The drive block 4 is mounted on the drive shaft 5 through the drive hole 44. A card anti-reverse mounting structure 43 ensures that the movable disk 3 is always assembled in the same manner and driven by the hexagonal shaft. The drive block 4 can have various shapes, such as square, and various card anti-reverse mounting structures 43, including asymmetric arrangements.

[0096] Because the spiral grooves 22 on the fixed disk 2 restrict the movement of seeds, the seed chamber is positioned close to the center of rotation. This means that the suction holes maintain a low velocity when capturing seeds within the population. According to the linear velocity calculation formula v=wr, decreasing the radius of rotation reduces the linear velocity. The slots of the moving disk 3 and the fixed disk 2 overlap to form a combined suction hole. The captured seeds are pushed along the spiral grooves 22 of the fixed disk 2 by radial grooves 31 until they are ejected at the end of the spiral grooves 22. (That is, after the radial grooves 31 reach the seeding pressure relief grooves 23, the spiral grooves 22 are no longer connected to the negative pressure chamber, and the seeds are no longer attracted and escape from the suction holes.) Seed-clearing teeth 313 are provided on both long sides of the slot holes of the radial groove 31, which are preferably serrated pairs of teeth. When the movable disk 3 rotates, the overlapping position of the slot holes of the radial groove 31 and the spiral groove 22 of the fixed disk 2 also moves from the proximal end to the distal end. Therefore, the pairs of teeth on the slot holes of the radial groove 31 will pass through the spiral groove 22 of the fixed disk 2 laterally in turn, that is, they will play a role in adjusting the adsorbed seeds during the seed migration process.

[0097] The centrifugal seeding method of the small-seeding device of the present invention reduces the passing speed of the suction holes within the seed population by changing the rotation radius of the suction holes, thereby improving the missed seeding rate and seeding efficiency, and realizing non-invasive seed cleaning of the seeding disc and reducing the reseeding rate. The method comprises the following steps:

[0098] The above-mentioned seeding tray is used, and the parameters of the seeding device are adjusted according to the characteristics of the seeds to be sown, so as to improve the suction hole's ability to absorb seeds with large differences in shape and size;

[0099] The movable plate 3 of the seeding plate is driven to rotate periodically relative to the fixed plate 2, and the suction holes capture the seeds to be sown from the seed filling area. The captured seeds to be sown are centrifugally transported along the spiral groove 22 of the fixed plate 2 along the suction holes and sequentially pass through the seed filling area, seed cleaning area, seed carrying area and seed throwing area; wherein the centrifugal transport includes seed filling near the rotation center within the seed population M, Archimedean spiral centrifugal motion in the seed cleaning area and uniform circular motion in the seed carrying area;

[0100] Among them, after the sowing seeds enter the seed-clearing area, they gradually move away from the rotation center, and the sowing speed increases; the sawtooth-shaped teeth of the radial groove 31 of the movable disk 3 sequentially remove the heavy-absorbed seeds through the spiral groove 22; after the sowing seeds enter the seed-carrying area, they perform uniform circular motion, and the circular motion speed of the seeds v c for: , to enhance the seed holding stability and seed holding capacity of the suction hole; after the sowing seeds enter the sowing area, they are released by the suction hole under the action of the sowing pressure relief groove 23.

[0101] The seed characteristics include physical and mechanical properties. The physical properties include seed length, width, thickness, density, porosity, sphericity, and moisture content. The mechanical properties include rolling friction coefficient, sliding friction coefficient, and stacking angle. The seed metering device parameters include the seeding rotation radius, seeding disk speed, number of suction holes on the seeding disk's rotating disc (3), seeding disk vacuum level, and the width of the spiral groove (22) on the seeding disk's fixed disc (2).

[0102] The seeding disc of the present invention is designed for breeding and sowing and is not suitable for high-speed field sowing. Four functional areas are set on the seeding disc: a seed filling area, a seed cleaning area, a seed carrying area, and a seed dropping area. Driven by the drive shaft 5, the movable disc 3 rotates periodically relative to the fixed disc 2. The suction holes formed by the combined seeding disc capture seeds from the seed filling area. Driven by the movable disc 3, the captured seeds move along the spiral groove 22 of the fixed disc 2 and pass through the four functional areas in sequence. The centrifugal movement of the captured seeds, driven by the movable disc 3, captures the seeds in the seed filling area of ​​the fixed disc 2 (i.e., the portion of the spiral groove 22 with a rotation radius close to the center of rotation) by the suction holes. The curve parameters of the seed filling area can be adjusted according to the seeding requirements (including seed quantity and plant spacing). After the seeds enter the seed-clearing area, they gradually move away from the center of rotation along the spiral groove 22 to increase the seed-dropping speed; at the same time, the spiral groove 22 of the fixed plate 2 and the radial groove 31 of the movable plate 3 move relative to each other, especially in the seed-clearing area, regular staggered motion occurs, and the tooth connection line 312 should be parallel to the tangent of the Archimedean spiral at the intersection of the two slots. The serrated teeth on the movable plate 3 sequentially pass through the spiral groove 22 to achieve the function of clearing the heavily sucked seeds; the seeds move from the seed-clearing area to the seed-carrying area, enhancing the seed-holding stability and seed-holding capacity of the combined suction holes. The seeds perform uniform circular motion in this area, and the circular motion speed of the seeds v c The calculation is done using the following formula: The relative movement of the movable disk 3 and the fixed disk 2 drives the seeds to the farthest end of the slot of the movable disk 3. Considering that the seeds have passed the highest point of seed return, the seed holding capacity can be enhanced by increasing the length of the suction hole; finally, the seeds are released by the suction hole in the seeding area under the action of the seeding pressure relief groove 23.

[0103] The slots of the movable disk 3 and the fixed disk 2 of the present invention are combined with each other, and the suction holes formed can be obtained by controlling the width of the two slots to obtain narrow and long suction holes dominated by the width of the slots of the fixed disk 2. The narrow and long suction holes have better adaptability to irregularly shaped seeds (such as seeds with obvious edge features such as corn). At the same time, larger seeds have larger characteristic sizes, which allows the seeds to block a longer distance when blocking the narrow and long suction holes, thereby obtaining a higher suction force. Similarly, the suction force obtained by small seeds is relatively small, so the adaptability to seed size is also advantageous. Moreover, when the narrow and long suction holes re-absorb seeds, due to the limitation of the narrow side, the re-absorbed seeds can only be arranged along the long side of the suction hole, so that the seed cleaning teeth 313 can complete the removal of the re-absorbed seeds. The spiral structure of the slots in fixed disk 2 restricts seeds to a single spiral during transport. The spiral's origin lies within population M and is relatively close to the center of rotation of movable disk 3. This reduces the speed and time it takes for the suction holes to pass through population M while maintaining a constant sowing speed. This improves the success rate of seed capture and ensures operational efficiency. The combined, narrow suction holes are highly adaptable to seed shapes and sizes. The serrated shape of their long sides facilitates the capture of multiple seeds, which are then arranged sequentially along the long sides of the suction holes. The relative movement of movable disk 3 and fixed disk 2 causes the suction holes to move relative to each other. The slots in movable disk 3 maintain their narrow, long characteristics and restrict the movement of the seeds. Seed-clearing teeth 313 are provided on the slots in movable disk 3. This relative movement causes the teeth to appear sequentially in the negative pressure channel 13 (i.e., within the combined suction hole area), resulting in alternating high and low serrations along the short sides of the combined suction holes, thereby scraping off excess seeds. When two seeds are absorbed by the narrow suction hole, the hole is completely blocked, causing the seeds to squeeze each other. The serrations increase the interaction between the seeds and force them out of the hole, achieving seed clearance. When only one seed remains, the suction hole is fully focused on that one seed, and the large unblocked area of ​​the suction hole acts to constrain the seed to the hole. The narrow suction hole holds all individual seeds, and the serrations can only cause the seeds to flip. Due to the arrangement of its seed cavity and rotation center, the seed tray is only suitable for small seed quantities and low-speed sowing operations such as breeding trials, providing technical support for breeding sowing operations.

[0104] The suction holes of the seeding disk of the present invention are composed of the slot holes of the movable disk 3 and the fixed disk 2, and integrate the functions of seed clearing and limiting the seed carrying trajectory. The seed carrying movement trajectory is limited by the slot holes of the fixed disk 2, and the slot holes of the movable disk 3 actively rotate to drive the seeds, pushing the seeds to perform centrifugal motion; the seed carrying needs in different functional areas are achieved by changing the radius size; and seed clearing is achieved with the help of the teeth; the fixed disk 2 limits the seed transportation curve to achieve low-speed seed bagging near the rotation center of the seeding disk, that is, low-speed seed capture; variable speed movement, that is, the rotation radius gradually increases and the linear speed gradually increases in the process of the seeds moving along the spiral line; the suction hole length is changed by the teeth, thereby changing the adsorption capacity of the suction hole, and a fluid method is used instead of a seed cleaning mechanism to force seed clearing.

[0105] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A seeding disc of a small seeding device, mounted on a seeding device base, characterized in that: include: A fixed plate is mounted on the seed metering device base and forms a vacuum negative pressure chamber with the seed metering device base, the vacuum negative pressure chamber being connected to a negative pressure pump through a negative pressure channel; a spiral groove is provided on the fixed plate, the spiral groove being arranged in sections corresponding to the seed filling area, seed cleaning area, seed carrying area and seed dropping area of ​​the fixed plate, and the spiral groove located at one end of the seed filling area is close to the center of the fixed plate, and the spiral groove located at one end of the seed dropping area is away from the center of the fixed plate and is correspondingly provided with a seed dropping pressure relief groove; the spiral groove is communicated with the vacuum negative pressure chamber, and the airflow in the negative pressure channel can only be sucked in through the spiral groove; A driving block is mounted on a driving shaft, wherein the driving shaft passes through the fixed plate and is connected to the seed metering device base; as well as A movable disc is mounted on the driving block adjacent to the fixed disc, and the driving block drives the movable disc to rotate relative to the fixed disc; a plurality of radial grooves are uniformly distributed along the circumference of the movable disc, and each radial groove forms an independent suction hole at the intersection with the spiral groove; when the movable disc rotates, the suction hole moves along the radial groove from the proximal end to the distal end along with the spiral groove to complete sowing and clearing of seeds; The seed filling curve distribution angle of the spiral groove in the seed filling area is α1, and -90°≤α1≤0°. The flow field disturbance velocity gradient boundary distribution range of the suction hole is calculated using the following formula: ； Among them, x, y, z are the values ​​of the spatial coordinate system OXYZ with the center of the suction hole as the origin, and the unit is mm; K b is the width of the suction hole, in mm; K l is the length of the suction hole, in mm; P is the vacuum degree of the suction hole, in Pa; Y va Y is the long radius of the boundary domain of the airflow velocity gradient of the suction hole, in mm; vb Y is the radius of the boundary region of the airflow velocity gradient of the suction hole, in mm; vc is the short radius of the airflow velocity gradient boundary domain of the suction hole, in mm; the bottom of the seed filling area is located within the gradient domain boundary range of the suction hole at the starting point of the seed filling curve distribution.

2. The seeding tray of the small seeding device according to claim 1, characterized in that: The seed clearing curve of the spiral groove in the seed clearing area is an Archimedean spiral, and the movement trajectory of the seeds is: ； Among them, R n is the seed gyration radius, in mm; a, b are constants; θ n is the helix angle, in degrees; The seeds are centrifuged at a constant radial speed v in the seed cleaning area. r With constant angular velocity w a sports: ； in, ; c is a constant; R1 is the initial gyration radius, in mm; R2 is the tail gyration radius, in mm; the spiral distribution angle of the seed clearing curve is α2, and 0°≤α2≤90°.

3. The seeding tray of the small seeding device according to claim 2, characterized in that: The inner side of the radial groove is provided with a seed cleaning tooth, which is a sawtooth tooth structure. The tooth connection line of the seed cleaning tooth is parallel to the tangent line of the Archimedean spiral at the intersection of the radial groove and the spiral groove. The tooth spacing L c Greater than the seed length; the midpoints of the tooth connection lines are located at intervals of L c On the equally spaced concentric circles, the number of teeth c n for: 。 4. The seeding tray of the small seeding device according to claim 3, characterized in that: Each pair of teeth of the seed cleaning teeth passes through the spiral groove in sequence during the seed migration process to change the adsorption force of the suction hole and adjust the seeds adsorbed on the suction hole.

5. The seeding tray of the small seeding device according to claim 2, characterized in that: The radial grooves are evenly distributed radially outward from the center of the moving disk, and the number of distribution is k n for: ； Among them, V p is the forward speed of the seeder, in cm / s; L is the plant spacing, in cm; n s is the rotating disk speed, in r / s; , c is a constant.

6. A centrifugal seeding method for a small seeding device, characterized in that: By changing the rotation radius of the suction hole to reduce the passing speed of the suction hole in the seed population, so as to improve the missed seeding rate and seeding efficiency, the method includes the following steps: Using the seeding disc according to any one of claims 2 to 5, and adjusting the parameters of the seeding device according to the characteristics of the seeds to be sown; The movable disc of the seeding disc is driven to rotate periodically relative to the fixed disc, and the suction holes capture the seeds to be sown from the seed filling area. The captured seeds to be sown are centrifugally moved along the spiral grooves of the fixed disc along with the suction holes, and sequentially pass through the seed filling area, the seed cleaning area, the seed carrying area and the seed dropping area; Among them, after the sowing seeds enter the seed cleaning area, they gradually move away from the rotation center, and the sowing speed increases; the sawtooth-shaped teeth of the radial groove clear the heavy seeds through the spiral groove in sequence; after the sowing seeds enter the seed carrying area, they make uniform circular motion, and the circular motion speed of the seeds v c for: , to enhance the seed holding stability and seed holding capacity of the suction hole; after the sowing seeds enter the sowing area, they are released by the suction hole under the action of the sowing pressure relief groove.

7. The centrifugal seeding method of the small seeding device according to claim 6, characterized in that: The characteristics of the seeds to be sown include physical characteristics and mechanical characteristics. The physical characteristics include the length, width, thickness, density, porosity, sphericity and moisture content of the seeds. The mechanical characteristics include the rolling friction coefficient, sliding friction coefficient and stacking angle of the seeds.

8. The centrifugal seeding method of the small seeding device according to claim 6, characterized in that: The parameters of the seeding device include the seeding rotation radius, the rotation speed of the seeding disk, the number of suction holes of the moving disk of the seeding disk, the vacuum degree of the seeding disk and the width of the spiral groove of the fixed disk of the seeding disk.

9. A small seed quantity metering device, characterized in that: The invention comprises the seeding disc according to any one of claims 2 to 5, and adopts the centrifugal seeding method according to any one of claims 6 to 8 for sowing.

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