High-speed precision seeder and pneumatic seed metering device and seed filling method thereof

Abstract

The invention relates to a high-speed precision seeder and an air pressure type seed sowing device and a seed filling method thereof, the high-speed precision seeder comprises the air pressure type seed sowing device, the air pressure type seed sowing device comprises a front shell, a rear shell, a seed box, a driving part, a seed sowing mechanism, a seed cleaning mechanism, a seed guiding mechanism and a spiral flow guiding mechanism, the seed sowing mechanism comprises a seed sowing disc and a seed unloading part, a positive pressure cavity is defined by the seed-metering disc and the front shell, the seed-metering disc comprises an inner seed-metering disc and an outer seed-metering disc, the outer seed-metering disc is installed on the inner seed-metering disc, and the inner seed-metering disc is connected with the driving component; a plurality of seed-metering holes are uniformly formed in the outer seed-metering disc, and disturbance teeth are arranged corresponding to the seed-metering holes; the spiral flow guide mechanism comprises flow guide spiral blades and splitter blades, the flow guide spiral blades are used for changing linear airflow of the positive pressure fan into spiral airflow, the splitter blades are used for dispersing the spiral airflow in the positive pressure cavity in the radial direction, and the rotation direction of the splitter blades is consistent with that of the seed metering disc. The invention further provides a seed filling method of the air pressure type seed-metering device, so that the resistance of a seed filling area is reduced, and the adhesive force is increased.

Description

Technical Field

[0001] The present invention relates to agricultural seeding machinery, in particular to a high-speed precision seeding machine suitable for soybeans / corn, a pneumatic seed metering device thereof, and a positive pressure airflow assisted seed filling method. Background Art

[0002] Soybeans and corn are important food and feed crops with broad economic and social value. Their yield and quality are directly linked to food security and agricultural development. Soybeans are a key oilseed crop and protein source, while corn, with its economic products covering three major industries, boasts a wide reach and a long industrial chain. Sowing quality is a key factor influencing yield.

[0003] Agricultural production is gradually moving toward large-scale production, with high speed and efficiency being the development trend. High-speed corn and soybean precision planters are a key development direction. As operating speeds increase, the seed disc rotates too fast, exacerbating field vibrations. This increases friction and collisions between seed groups during seed filling, shortening seed filling time and increasing the rate of missed seeding. This also increases the time difference in seed movement during seeding and the collision between seeds and the seed guide tube. Consequently, high-speed seeding systems commonly suffer from problems such as high missed seeding rates and poor plant spacing uniformity. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a high-speed precision seeder and its pneumatic seed metering device and seed filling method in view of the above-mentioned defects of the prior art.

[0005] In order to achieve the above object, the present invention provides a pneumatic seed metering device, which includes:

[0006] front shell;

[0007] The rear shell is connected to the front shell and together they enclose a closed accommodating space, the closed accommodating space including a seed filling area, a seed cleaning area and a seed throwing area;

[0008] A seed box is connected to the front shell and is located on a side away from the rear shell. The seed box is provided with a positive pressure air pipe interface, a seed inlet and a seed outlet. The positive pressure air pipe interface is connected to the positive pressure fan.

[0009] A driving component is mounted on the rear housing;

[0010] The seeding mechanism includes a seeding disc and a seed unloading component. The seeding disc and the front shell enclose a positive pressure chamber. The seeding disc includes an inner seeding disc and an outer seeding disc. The outer seeding disc is installed on the inner seeding disc, and the inner seeding disc is connected to the driving component. A plurality of seeding holes are evenly arranged on the outer seeding disc, and disturbance teeth are provided corresponding to the seeding holes. When the driving component drives the outer seeding disc to rotate through the inner seeding disc, the disturbance teeth disturb the seed population, so that the seeds can replenish the vacant spaces of the previous seeds in time to reduce leakage.

[0011] a seed clearing mechanism, arranged on the front shell corresponding to the seed clearing area;

[0012] a seed guiding mechanism, arranged on the front shell corresponding to the seeding area; and

[0013] The spiral guide mechanism includes a guide spiral blade and a diverter blade. One end of the guide spiral blade is inserted into the positive pressure air pipe interface to change the linear airflow of the positive pressure fan into a spiral airflow entering the closed accommodation space; the other end of the spiral blade is connected to the diverter blade; the diverter blade is installed in the front shell to disperse the spiral airflow along the radial direction, and the rotation direction is consistent with the seed disc.

[0014] The above-mentioned pneumatic seed metering device, wherein the spiral guide mechanism also includes a seed blocking plate, which is installed in the front shell corresponding to the guide spiral blade. The seed blocking plate is a mesh structure, which is used to prevent excess seeds cleared by the seed cleaning mechanism from entering the spiral guide mechanism.

[0015] In the above-mentioned pneumatic seed metering device, the guide spiral blade and the diverter blade are integrally formed and have the same pitch.

[0016] The above-mentioned pneumatic seed metering device, wherein the seeding disk also includes a seeding silicone pad, which is installed on the disk surface of the seeding outer disk to increase the adhesion friction of the seeds; a plurality of seed holes are evenly arranged on the seeding silicone pad, and the seed holes correspond one-to-one to the seeding holes, the seed holes are round holes, and the seeding holes are elliptical holes.

[0017] The above-mentioned pneumatic seed metering device, wherein the seed cleaning mechanism includes at least one seed cleaning component and a seed cleaning slide, the seed cleaning component includes a seed cleaning wheel, a slider and an adjustment gear, the seed cleaning slide is arranged on the front shell, the slider is installed in the seed cleaning slide and moves along the seed cleaning slide; the adjustment gear is installed in the gear light hole arranged on the front shell and rotates in the gear light hole; the slider is provided with a rack, a clamping shaft and a baffle, the rack is meshed with the gear, and the tooth top of the adjustment gear abuts against the inner side of the baffle; the seed cleaning wheel is installed on the clamping shaft and is arranged corresponding to the seeding hole.

[0018] The above-mentioned pneumatic seed metering device, wherein the seed guide mechanism includes a seed guide inlet, a first seed guide tube and a second seed guide tube connected in sequence, the seed guide inlet is arranged on the upper part of the front shell corresponding to the seed cleaning mechanism, the first seed guide tube is a streamlined structure with an arc corresponding to the initial velocity of the seed, and the second seed guide tube is a fastest descent curve structure corresponding to the friction force of the seed.

[0019] The above-mentioned pneumatic seed metering device, wherein the seeding mechanism also includes a seed gathering plate and an air blocking plate installed on the front shell, the seed gathering plate is used to accumulate seeds near the seeding holes; the air blocking plate is flat on one side of the seeding disk, used to block the seeding holes to which no seeds are attached, thereby reducing the ineffective leakage of gas in the positive pressure chamber.

[0020] The above-mentioned pneumatic seed metering device, wherein the seed unloading component includes a seed unloading wheel and a forced seed unloading wheel, the seed unloading wheel is installed on the seed unloading wheel embedment, the seed unloading wheel embedment and the forced seed clearing wheel are installed on the air blocking bracket, and the air blocking bracket is installed on the rectangular spline of the rear shell through the air blocking rectangular spline, and the phase of seed clearing can be adjusted by adjusting the relative angle between the air blocking rectangular spline and the rectangular spline of the rear shell.

[0021] In order to better achieve the above-mentioned object, the present invention further provides a method for filling a seed with a pneumatic seed meter, wherein the method for performing positive pressure airflow-assisted seed filling for the pneumatic seed meter includes the following steps:

[0022] By adjusting the direction of the positive pressure airflow, the resistance of the seed filling area is reduced. The spiral guide mechanism changes the straight airflow entering the positive pressure chamber into a spiral airflow, and the spiral airflow is dispersed in the positive pressure chamber along the radial direction. The rotation direction is consistent with the seed disc, so that the airflow direction is opposite to the resistance direction during operation, thereby improving the seed filling capacity; and

[0023] The adhesion of seeds is increased by increasing the air pressure difference on both sides of the seed hole. The seed hole is set to a double-structure hole type of circular hole and elliptical hole to improve the airtightness of the seed hole when the seeds are in different pressure attachment postures and reduce the effective gap area.

[0024] In order to better achieve the above-mentioned purpose, the present invention also provides a high-speed precision seeder, which includes the above-mentioned pneumatic seed metering device and adopts the above-mentioned seed filling method to perform positive pressure airflow assisted seed filling.

[0025] The technical effects of the present invention are:

[0026] The pneumatic seed metering device with positive pressure airflow assisted seed filling of the present invention can be used on soybean / corn high-speed precision seeders. It adopts a positive pressure assisted seed filling method to control the gas flow direction in the seed cavity, reduces the seed filling resistance, reduces leakage, and improves the single-grain rate. It then uses high-speed airflow to deliver seeds and seed guide tubes to control seeds in sections, effectively improving the uniformity of sowing.

[0027] 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

[0028] Figure 1 This is a schematic structural diagram of a pneumatic seed metering device according to an embodiment of the present invention;

[0029] Figure 2 An exploded view of a pneumatic seed metering device according to an embodiment of the present invention;

[0030] Figure 3A This is a structural diagram of a seeding disc according to an embodiment of the present invention;

[0031] Figure 3B This is a schematic diagram of a seed hole structure according to an embodiment of the present invention;

[0032] Figure 4A This is a schematic structural diagram of a spiral flow guide mechanism according to an embodiment of the present invention;

[0033] Figure 4B for Figure 4A Side view of

[0034] Figure 5 This is a schematic diagram of the working of a pneumatic seed metering device according to one embodiment of the present invention;

[0035] Figure 6 This is a schematic structural diagram of a seed cleaning component according to an embodiment of the present invention;

[0036] Figure 7 A schematic diagram of the internal gas flow of a pneumatic seed metering device according to an embodiment of the present invention;

[0037] Figures 8A-8D Schematic diagram of seed attachment posture according to an embodiment of the present invention.

[0038] Among them, the reference numerals

[0039] 1 front shell

[0040] 11 gear light holes

[0041] 12 threaded fixing holes

[0042] 13 pores

[0043] 2 back shell

[0044] 21 mounting holes

[0045] 22 vent holes

[0046] 23 Shell

[0047] 24 rotating shell bearing

[0048] 25 rear shell rectangular spline

[0049] 3 types of boxes

[0050] 31 sealing ring

[0051] 32 sealing cover

[0052] 33 seed entrance

[0053] 34 seed exports

[0054] 35 positive pressure trachea interface

[0055] 4. Seed clearing agency

[0056] 41 Clearing parts

[0057] 411 seed clearing wheel

[0058] 412 Slider

[0059] 413 rack

[0060] 414 card shaft

[0061] 415 baffle

[0062] 416 adjustment gear

[0063] 42 Clearing Slide

[0064] 43 set screw 5 seeding mechanism

[0065] 51 seed tray

[0066] 511 seeding silicone pad 512 seeding outer plate

[0067] 513 seed holes

[0068] 514 disturbance tooth

[0069] 515 seed tray

[0070] 516 types of holes

[0071] 52 unloading parts

[0072] 521 unloading wheel

[0073] 522 forced unloading wheel 523 unloading wheel embedded with 53 seed gathering plate

[0074] 54 air blocking board

[0075] 55 gas blocking stent

[0076] 56 air blocking rectangular spline 6 guide mechanism

[0077] 61 introduction entrance

[0078] 62 first seed tube

[0079] 63 second seed guide tube 7 spiral guide mechanism

[0080] 71 guide spiral blades

[0081] 72 splitter blades

[0082] 73 seed retaining plate

[0083] 8 drive components

[0084] 81 motor bearings

[0085] 9Quick locking mechanism

[0086] 91 quick lock knob

[0087] 92 quick lock cam

[0088] Ⅰ Seeding area

[0089] Ⅱ Seed Clearing Area

[0090] III Planting area

[0091] a Positive pressure air inlet

[0092] bSeed cavity

[0093] c Positive pressure chamber

[0094] d differential pressure chamber

[0095] e High-speed seeding airflow

[0096] f transition cavity DETAILED DESCRIPTION

[0097] The structural principle and working principle of the present invention are described in detail below with reference to the accompanying drawings:

[0098] The high-speed precision seeder of the present invention may include a traction mechanism, a fertilizing device, a pneumatic seed metering device, a suppression device, a walking device and a sowing furrowing device, etc. The composition, structure, mutual position relationship, connection relationship and function of other parts of the precision seeder are all relatively mature existing technologies, so they will not be repeated here. The following is a detailed description of the pneumatic seed metering device of the present invention and its positive pressure airflow assisted seed filling method.

[0099] See also Figure 1 and Figure 2 , Figure 1This is a schematic structural diagram of a pneumatic seed metering device according to an embodiment of the present invention. Figure 2 The exploded view of the pneumatic seed metering device according to one embodiment of the present invention is suitable for high-speed operation, and comprises: a front shell 1; a rear shell 2, connected to the front shell 1, and together enclosing a closed accommodating space, the closed accommodating space comprises a seed filling area I, a seed clearing area II and a seed dropping area III; a seed box 3, connected to the front shell 1, and located on a side away from the rear shell 2, the seed box 3 is provided with a positive pressure air pipe interface 35, a seed inlet 33 and a seed outlet 34, the positive pressure air pipe interface 35 is connected to the positive pressure fan, and is a pneumatic pressure device. The seeding device is connected to an external air pipe to increase the air pressure interface; the driving component 8 is installed on the rear shell 2; the seeding mechanism 5 includes a seeding disc 51 and a seed unloading component 52, the seeding disc 51 and the front shell 1 enclose a positive pressure chamber c, the seeding disc 51 includes a seeding inner disc 515 and a seeding outer disc 512, the seeding outer disc 512 is installed on the seeding inner disc 515, and the seeding inner disc 515 is connected to the driving component 8; the seeding outer disc 512 is evenly provided with multiple a seeding hole 513, corresponding to which a disturbance tooth 514 is provided; when the driving component 8 drives the seeding outer disk 512 to rotate through the seeding inner disk 515, the disturbance tooth 514 disturbs the seed population, so that the seeds can replenish the vacant space of the previous seeds in time to reduce leakage; a seed clearing mechanism 4 is arranged on the front shell 1 corresponding to the seed clearing area II; a seed guiding mechanism 6 is arranged on the front shell 1 corresponding to the seeding area III; and a spiral guide mechanism 7, including a guide spiral blade 71 and a diverter blade 72, one end of the guide spiral blade 71 is inserted into the positive pressure air pipe interface 35, for changing the straight airflow of the positive pressure fan into a spiral airflow entering the enclosed accommodating space; the other end of the spiral blade is connected to the diverter blade 72; the diverter blade 72 is installed in the front shell 1, for dispersing the spiral airflow along the radial direction and making it rotate in the positive pressure chamber c, and the rotation direction is consistent with that of the seeding disk 51.

[0100] In this embodiment, the seeding mechanism 5 also includes a seed collecting plate 53 and an air blocking plate 54 mounted on the front shell 1. The seed collecting plate 53 is used to accumulate the seeds entering the seed box 3 and the excess seeds cleared from the seeding disc 51 near the seeding hole 513; the air blocking plate 54 is flat on the side of the seeding disc 51 and is used to block the seeding holes 513 without seeds attached, thereby reducing the ineffective leakage of gas in the positive pressure chamber c. The seed unloading component 52 includes a seed unloading wheel 521 and a forced seed unloading wheel 522. The seed unloading wheel 521 is mounted on the seed unloading wheel inlay 523. The seed unloading wheel inlay 523 and the forced seed clearing wheel 411 are mounted on the air blocking bracket 55. The air blocking bracket 55 is mounted on the rear shell rectangular spline 25 via the air blocking rectangular spline 56. The seed clearing phase can be adjusted by adjusting the relative angle between the air blocking rectangular spline 56 and the rear shell rectangular spline 25.

[0101] In this embodiment, a sealing ring 31 is attached to the seed inlet 33 above the seed box 3, and a portable and detachable sealing cover 32 is installed above the sealing ring 31, which allows for portable seeding and prevents air leakage after seeding. The seeds in the seed box 3 and the air flow of the positive pressure air pipe interface 35 use different channels. The seeds in the seed box 3 are added through the seed inlet 33 and enter the seed meter from the seed outlet 34 to form a pile. The positive pressure airflow enters the seed meter from the positive pressure airflow inlet a. The seed box 3 is mounted on the front shell 1 using screws, and its seed outlet 34 and the air flow outlet of the positive pressure air pipe interface 35 correspond to the air hole 13 of the front shell 1. The air hole 13 can be connected to an external air pressure sensor to monitor the air pressure in the positive pressure chamber c of the seed meter in real time. The rear shell 2 is the fixing part of the pneumatic seed meter and is mounted on the sowing unit of the high-speed precision seeder through the mounting hole 21. The drive component 8 is preferably a motor, mounted on the rear housing 2, and serves as the power source for the seed meter. The motor's rotating shaft is mounted on the seed inner disc 515 via a motor bearing 81, further reducing the impact of installation errors on the rotational stability of the seed disc 51. This embodiment may also be provided with a quick locking mechanism 9, comprising a quick lock cam 92 and a quick lock knob 91. The quick lock cam 92 is mounted on the rear housing 2 and connected to the quick lock knob 91 mounted on the front housing 1 to achieve rapid disassembly of the front housing 1 from the rear housing 2. The device may also include a rotating housing 23, which is mounted on the rear housing 2 via a rotating housing bearing 24 and can rotate relative to the rear housing 2. The other side of the rotating housing 23 is in contact with the seed outer disc 512 of the seed disc 51 and can rotate with the seed outer disc 512.

[0102] See also Figure 3A and Figure 3B , Figure 3A This is a structural diagram of a seeding disc 51 according to an embodiment of the present invention. Figure 3BThe diagram below is a schematic diagram of the seeding holes 513 according to one embodiment of the present invention. This seeding disc 51 is primarily designed for soybean and corn seeds. The disc 51 in this embodiment also includes a seeding silicone pad 511, mounted on the surface of the seeding outer disc 512 to increase the frictional adhesion between the seeds and the disc 51. The silicone pad 511 is evenly distributed with multiple seeding holes 516, each corresponding to the seeding holes 513. The seeding holes 516 are preferably circular, while the seeding holes 513 are preferably elliptical to increase adhesion. The seeding holes 513 are divided into a front circular hole and a rear elliptical hole. Structurally, the circular holes are located on the seeding silicone pad 511, while the elliptical holes are located on the seeding outer disc 512. The circular holes are made of silicone, making them more easily adhered to the seeds and increasing frictional adhesion. The silicone pad 511 can be glued to the seeding outer disc 512 to prevent axial disengagement of the silicone pad 511. During rotation, the radial resistance of the seeding silicone pad 511 is borne by the rounded corners on its outer surface. The inner seeding disc 515 is mounted on the motor's shaft and rotates under the motor's drive. The outer seeding disc 512 is mounted on the inner seeding disc 515 and rotates with it. The outer seeding disc 512 has disturbing teeth 514 that disturb the seed population during operation, allowing seeds to replenish the vacant spaces left by the previous seeds and reducing missed seeding.

[0103] See also Figure 4A and Figure 4B , Figure 4A This is a structural diagram of a spiral flow guide mechanism 7 according to an embodiment of the present invention. Figure 4B for Figure 4A The spiral guide mechanism 7 of this embodiment further includes a seed retaining plate 73, which is installed in the front shell 1 corresponding to the guide spiral blade 71. The seed retaining plate 73 is preferably a mesh structure, which is used to prevent excess seeds cleared by the seed clearing mechanism 4 from entering the spiral guide mechanism 7. The guide spiral blade 71 and the diverter blade 72 are key components for guiding the airflow. Preferably, the guide spiral blade 71 and the diverter blade 72 are integrally formed and have the same pitch, preferably in the range of 50-60 mm. The guide spiral blade 71 and the diverter blade 72 preferably each include 3 blades.

[0104] See also Figure 5 , Figure 5 The diagram of the working of the pneumatic seed metering device according to one embodiment of the present invention is shown in FIG. The seed guide mechanism 6 of this embodiment includes a seed guide inlet 61, a first seed guide tube 62, and a second seed guide tube 63 connected in sequence. The seed guide inlet 61 is arranged on the upper part of the front shell 1 corresponding to the seed cleaning mechanism 4. The first seed guide tube 62 is a streamlined structure with an arc corresponding to the initial velocity of the seed, and the second seed guide tube 63 is a structure with the fastest drop curve corresponding to the friction force of the seed. Figure 5As shown, the air blocking plate 54 is flat against one side of the seeding disc 51 and is used to block the seeding holes 513 without seeds attached, thereby reducing the ineffective leakage of gas in the positive pressure chamber c and reducing energy consumption. The air blocking bracket 55 is mounted on the rear shell rectangular spline 25 via the air blocking rectangular spline 56. The phase of seed clearing can be adjusted by adjusting the relative angle between the air blocking rectangular spline 56 and the rear shell rectangular spline 25. The seed unloading wheel 521 is mounted on the seed unloading wheel inlay 523. The seed unloading wheel inlay 523 and the forced seed clearing wheel 411 are mounted on the air blocking bracket 55. The seed unloading wheel 521 is preferably made of soft rubber and is mounted on the seed unloading wheel inlay 523 to reduce the friction between the seed unloading wheel 521 and the air blocking bracket 55. The first seed guide tube 62 and the second seed guide tube 63 are installed on the front shell 1, and the seed guide inlet 61 is installed on the first seed guide tube 62. The seeds enter the first seed guide tube 62 through the seed guide tube inlet. The first seed guide tube 62 is designed according to the oblique throwing motion of the seed with initial velocity. Using the first seed guide tube 62 allows the seeds to enter the seed guide tube in advance, reducing the risk of seeds being lost while moving on the seed plate 51, increasing the seed acceleration time in the airflow, increasing the seed speed, and thus improving the uniformity of sowing. After passing through the first seed guide tube 62, the seeds slide down along the side wall to enter the second seed guide tube 63. The second seed guide tube 63 is designed according to the fastest descent line considering friction, and its curve is:

[0105]

[0106] This formula is a trajectory equation, where x and y are the coordinate positions of the trajectory in the Cartesian coordinate system, and t is the independent variable, and the range of t is (0, 0.92π).

[0107] See also Figure 6 , Figure 6 The figure is a schematic structural diagram of a seed-clearing component 41 according to an embodiment of the present invention. The seed-clearing mechanism 4 of this embodiment includes at least one seed-clearing component 41 and a seed-clearing slide 42. The seed-clearing component 41 includes a seed-clearing wheel 411, a slider 412, and an adjustment gear 416. The seed-clearing slide 42 is provided on the front housing 1, and the slider 412 is mounted within the seed-clearing slide 42 and moves along the seed-clearing slide 42. The adjustment gear 416 is mounted within the gear aperture 11 provided on the front housing 1 and rotates within the gear aperture 11. The slider 412 is provided with a rack 413, a clamping shaft 414, and a baffle 415. The rack 413 meshes with the gear, and the top of the teeth of the adjustment gear 416 abuts against the inner side of the baffle 415. The seed-clearing wheel 411 is mounted on the clamping shaft 414 and is provided corresponding to the seed-discharging hole 513.

[0108] In this embodiment, the seed cleaning mechanism 4 is installed inside the front shell 1. The seed cleaning mechanism 4 is preferably composed of four groups of seed cleaning components 41. Each group of seed cleaning components 41 can be manually adjusted independently. Figure 6As shown, the slider 412 is installed in the seed cleaning slide 42, and the slider 412 can move along the slide. The set screw 43 is installed in the threaded set hole 12, which can fix the slider 412 when it is not sliding. The adjustment gear 416 is installed in the gear light hole 11, and the adjustment gear 416 can rotate in the gear light hole 11. The adjustment gear 416 and the rack 413 form a gear rack 413 structure. The gear end of the adjustment gear 416 is against the inner side of the baffle 415, which can limit the axial movement of the adjustment gear 416. The adjustment gear 416 has two ends, one end is a cylindrical end with a hexagonal hole, and the cylindrical end is inserted into the gear light hole 11 and can rotate in the gear light hole 11. The rotation method is to use an hexagonal wrench to insert the hexagonal hole of the cylindrical end to rotate the adjustment gear 416. The other end of the adjustment gear 416 is a gear end, and the gear tooth structure of the gear end is engaged with the rack 413. The seed cleaning wheel 411 is the working component of the seed cleaning unit 41, used to directly contact the seeds attached to the seeding disc 51 to remove excess seeds and achieve single-seed seeding. The seed cleaning wheel 411 is mounted on the clamping shaft 414 and can rotate on the clamping shaft 414. The clamping shaft 414 has a long groove to facilitate the installation and axial positioning of the seed cleaning wheel 411. During operation, the gear 416 can be adjusted by rotating it in real time, driving the rack 413 and the slider 412 to move within the seed cleaning slide rail, so that the seed cleaning wheel 411 is moved closer to or away from the seeding hole 513 to achieve the best seed cleaning effect. After the adjustment is completed, the set screw 43 is rotated to tighten the slider 412 to fix the seed cleaning wheel 411.

[0109] The pneumatic seed metering device with positive pressure airflow assisting seed filling can improve seed filling capacity, reduce seed omission caused by seed shape and attachment posture, and improve seeding quality during high-speed operation by controlling the direction of positive pressure airflow to assist seed filling, independent seed cleaning and high-speed seeding.

[0110] See also Figure 7 and Figures 8A-8D , Figure 7 This is a schematic diagram of the internal gas flow of a pneumatic seed metering device according to an embodiment of the present invention. Figures 8A-8D The diagram is a schematic diagram of the seed attachment posture of an embodiment of the present invention. The seed filling method of the pneumatic seed metering device of the present invention uses positive pressure airflow to assist seed filling and is suitable for pneumatic seed metering devices of high-speed precision seeding machines for corn, soybeans, etc., and includes the following steps:

[0111] By adjusting the direction of the positive pressure airflow, the resistance of the seed filling area I is reduced. The spiral guide mechanism 7 changes the straight airflow entering the positive pressure chamber C into a spiral airflow, and the spiral airflow is dispersed in the positive pressure chamber C along the radial direction. The rotation direction is consistent with the seed disc 51, so that the airflow direction is opposite to the resistance direction during operation, thereby improving the seed filling capacity; and

[0112] By increasing the pressure difference on both sides of the seed hole 516, the adhesion of the seeds is increased, and the seed hole 513 is set to a double-structure hole type of a circular hole and an elliptical hole to improve the sealing of the seed hole 516 when the seeds are in different pressure attachment postures and reduce the effective gap area. Figure 8A Pressure difference force when seeds are pressed ( Figure 8A The soybean seed is placed with the round end close to the seed hole 516 of the seeding silicone pad 511. Figure 8B for Figure 8A side view), and can reduce the seed Figure 8C The effective gap area when the seeds are pressed and attached increases the pressure difference force ( Figure 8C The soybean seed places one end of the oval close to the seed hole 516 of the seeding silicone pad 511. Figure 8D for Figure 8C side view).

[0113] like Figure 5 and Figure 8B As shown, the seed metering device has three operating areas during operation: seed filling area I, seed clearing area II, and seed delivery area III. Ensuring that seeds are stably filled into each seed hole 516 in seed filling area I is a prerequisite for ensuring no missed seeds. Avoiding overfilling is a key factor in reducing pressure in seed clearing area II and ensuring single seed sowing by the seed metering device. In seed filling area I, as the seeds transition from rest to uniform circular motion with the seed disc 51, the conservation of kinetic energy yields:

[0114]

[0115] When the seeds are stably attached to the seed tray 51, Figures 8A-8D As shown, the force relationship is:

[0116]

[0117] Among them, v z is the speed at which the seeds rotate with the seed disc 51, in m / s; m is the average mass of corn seeds, in kg; ω is the angular velocity of the seed disc 51, in rad / s; R is the distance between the seed hole 513 and the center of the seed disc 51, in m; F g is the thrust of the airflow on the seeds, in N; F c F is the resultant force of the seed tray 51 acting on the seeds, in N; r is the resistance of the population to the attached seeds, in N; F cσ F c The force component parallel to the seed disc 51; θ is F cf The angle with the x direction, in degrees; α, β, γ are F cσ 、F g、F c The angle with the x-direction, in degrees.

[0118] When other parameters remain unchanged, by changing the thrust of the airflow on the seeds, the resistance of the seed filling area I can be effectively reduced, the airflow resistance is converted into power, and the probability of leakage is reduced. The gas enters the positive pressure chamber c along the pipeline and passes through the spiral guide mechanism 7 to change the direction of the airflow to the opposite direction of the resistance during operation to improve the seed filling capacity.

[0119] When the seeds are attached to the seed disc 51, the force perpendicular to the seed disc applied to the seeds comes from the pressure difference on both sides of the seed disc 51. By increasing the pressure difference, the force F exerted on the seeds by the seed disc 51 due to friction can be increased. c This increases the F content to prevent seeds from falling off. c The force F parallel to the seed disc 51 cσ The air pressure difference when the seeds are working on the seed tray 51 is:

[0120] F P =A h ·△P eff

[0121] Since the seeds are irregular in shape, the pores 13 cannot be completely blocked, which reduces the local pressure difference on both sides of the seeds. Therefore, the effective pressure is:

[0122]

[0123] The air leakage from the seed hole 516 will cause disturbance to the seeds, so the disturbance coefficient λ (0-1) is introduced. At this time, the pressure difference force is:

[0124]

[0125] Among them, A h is the effective area of ​​seeds, in m 2 ; ΔPeff is the effective pressure difference on both sides of the seed, in Pa; ΔP is the pressure difference on both sides of the seed tray 51, in Pa; ρ is the air density, in kg / m 3 ;v gap is the average air velocity in m / s; A gap is the effective gap area, in m 2 .

[0126] The spiral guide mechanism 7 guides the airflow through the airflow channel formed by the positive pressure air pipe interface 35 and the front shell 1. The airflow flows in the channel. The guide spiral blade 71 and the diverter blade 72 have different functions. When the airflow passes through the guide spiral blade 71, the airflow changes from flowing straight into the positive pressure chamber c to rotating and entering the positive pressure chamber c forward. At this time, the airflow passes through the diverter blade 72 and is further accelerated in the radial direction by the diverter blade 72 and decelerated in the axial direction, so that the airflow is dispersed in the radial direction. The gas flow inside the pneumatic seed metering device is as follows. Figure 7 As shown in the figure, the arrows indicate the direction of airflow, and the colors indicate the three types of airflow. The yellow arrow indicates the airflow in the positive pressure chamber c, the red arrow indicates the airflow leaking out of the positive pressure chamber c, and the green airflow indicates the airflow that has left the positive pressure chamber c. The positive pressure airflow enters from the positive pressure airflow inlet a channel of the positive pressure airflow interface, passes through the spiral channel formed by the guide spiral blade 71 and the positive pressure airflow interface, making the airflow spiral, and then the airflow is rotated in the positive pressure chamber c by the diverter blade 72, and the direction is consistent with the rotation direction of the seed disc 51, wherein the positive pressure chamber c is formed by the front shell 1 and the seed disc 51. The gas in the positive pressure chamber c is leaked through two channels. A small amount of gas leaks through the gap between the seeds, the air blocking plate 54 and the seeding hole 513, and a large amount of gas leaks through the high-speed seed guide airflow e area formed by the seed guide inlet 61, the first seed guide tube 62, and the second seed guide tube 63. Gas leaking through the seeding hole 513 enters the pressure differential chamber d, which is surrounded by the seeding disc 51 and the rotating shell 23. The pressure in the pressure differential chamber d is relatively low, causing the seeding hole 513 to form an air pressure difference on both sides of the seeding disc 51. The air in the pressure differential chamber d flows into the atmospheric pressure from the air leakage hole 22 through the transition chamber f, which is the inner cavity of the rear shell 2.

[0127] Before operation, seeds are added to the seed box 3 through the seed inlet 33 of the seed box 3. The seeds enter the positive pressure chamber c through the seed outlet 34 of the seed chamber b. The seeds are then deposited in front of the seed plate 51 by the seed collecting plate 53. The fan is turned on to allow positive pressure air to enter from the positive pressure air pipe interface 35, filling the entire seed meter; a certain pressure difference is generated on both sides of the seed plate 51. During this process, the spiral guide mechanism 7 rotates the airflow in the required direction.

[0128] During operation, the motor rotates, thereby driving the seed disc 51 to rotate. Under the action of the pressure difference on both sides of the seed disc 51, the seeds are attached to the seeding silicone pad 511 in front of the seeding hole 513. Taking soybeans as an example, according to the ellipsoidal shape of soybeans, their attachment postures on the seed disc 51 can be divided into two types, such as Figure 8A As shown, the soybean seed has one round end pressed against the seed hole 516 of the seeding silica gel pad 511. Due to the flexibility of silica gel, the sealing performance of the seed hole 516 in this state can be improved. Figure 8CAs shown, the soybean seed places one elliptical end close to the seed hole 516 position of the seeding silica gel pad 511. At this time, the elliptical structure of the seeding hole 513 can reduce the impact of airflow leakage on the seeds and reduce the burden on the seed cleaning mechanism 4 caused by a large number of repeated seed fillings. The structure of the seeding hole 513 allows the positive pressure airflow to enter the elliptical hole side from the circular hole side and the airflow on both sides to contract inward when passing through the seeding hole 513. At this time, when the seed is attached to one side of the circular hole, it is pressed against the seeding disk 51 by the pressure difference, and the airflow leaking from the seed hole 516 is reduced, and the flow rate is reduced, which can effectively increase the seeding efficiency. Figure 8C The success rate of seed filling with the correct posture is improved, the probability of repeated seed filling is reduced, and the burden on the seed cleaning mechanism 4 is reduced.

[0129] 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 pneumatic seed metering device, characterized in that: include: front shell; The rear shell is connected to the front shell and together they enclose a closed accommodating space, the closed accommodating space including a seed filling area, a seed cleaning area and a seed throwing area; A seed box is connected to the front shell and is located on a side away from the rear shell. The seed box is provided with a positive pressure air pipe interface, a seed inlet and a seed outlet. The positive pressure air pipe interface is connected to the positive pressure fan. A driving component is mounted on the rear housing; The seeding mechanism includes a seeding disc and a seed unloading component. The seeding disc and the front shell enclose a positive pressure chamber. The seeding disc includes an inner seeding disc and an outer seeding disc. The outer seeding disc is mounted on the inner seeding disc and connected to the driving component. A plurality of seeding holes are evenly arranged on the outer seeding disc, and disturbance teeth 514 are provided corresponding to the seeding holes. When the driving component drives the outer seeding disc to rotate through the inner seeding disc, the disturbance teeth 514 disturb the seed population, so that the seeds can replenish the vacant spaces of the previous seeds in time to reduce leakage. a seed clearing mechanism, arranged on the front shell corresponding to the seed clearing area; a seed guiding mechanism, arranged on the front shell corresponding to the seeding area; and The spiral guide mechanism includes a guide spiral blade and a diverter blade. One end of the guide spiral blade is inserted into the positive pressure air pipe interface to change the linear airflow of the positive pressure fan into a spiral airflow entering the closed accommodation space; the other end of the spiral blade is connected to the diverter blade; the diverter blade is installed in the front shell to disperse the spiral airflow along the radial direction, and the rotation direction is consistent with the seed disc.

2. The pneumatic seed metering device according to claim 1, characterized in that: The spiral guide mechanism also includes a seed blocking plate, which is installed in the front shell corresponding to the guide spiral blade. The seed blocking plate is a mesh structure and is used to prevent excess seeds cleared by the seed cleaning mechanism from entering the spiral guide mechanism.

3. The pneumatic seed metering device according to claim 1, characterized in that: The guide spiral blade and the splitter blade are integrally formed and have the same pitch.

4. The pneumatic seed metering device according to claim 1, characterized in that: The seeding plate also includes a seeding silicone pad, which is installed on the surface of the seeding outer plate to increase the adhesion friction of the seeds; a plurality of seed holes are evenly arranged on the seeding silicone pad, and the seed holes correspond one-to-one to the seeding holes. The seed holes are round holes, and the seeding holes are elliptical holes.

5. The pneumatic seed metering device according to claim 1, characterized in that: The seed cleaning mechanism includes at least one seed cleaning component and a seed cleaning slide, and the seed cleaning component includes a seed cleaning wheel, a slider and an adjustment gear. The seed cleaning slide is arranged on the front shell, and the slider is installed in the seed cleaning slide and moves along the seed cleaning slide; the adjustment gear is installed in the gear light hole arranged on the front shell and rotates in the gear light hole; the slider is provided with a rack, a card shaft and a baffle, the rack is engaged with the gear, and the tooth top of the adjustment gear abuts against the inner side of the baffle; the seed cleaning wheel is installed on the card shaft and is arranged corresponding to the seed hole.

6. The pneumatic seed metering device according to claim 1, characterized in that: The seed guide mechanism includes a seed guide inlet, a first seed guide tube and a second seed guide tube connected in sequence. The seed guide inlet is arranged on the upper part of the front shell corresponding to the seed cleaning mechanism. The first seed guide tube is a streamlined structure with an arc corresponding to the initial velocity of the seed's oblique throwing. The second seed guide tube is a fastest descent curve structure corresponding to the friction force of the seed.

7. The pneumatic seed metering device according to claim 1, characterized in that: The seeding mechanism also includes a seed gathering plate and an air blocking plate installed on the front shell. The seed gathering plate is used to accumulate seeds near the seeding holes; the air blocking plate is flat on one side of the seeding disk and is used to block the seeding holes to which no seeds are attached, thereby reducing ineffective leakage of gas in the positive pressure chamber.

8. The pneumatic seed metering device according to claim 1, characterized in that: The unloading component includes a unloading wheel and a forced unloading wheel. The unloading wheel is installed on the unloading wheel embedment. The unloading wheel embedment and the forced seed cleaning wheel are installed on the air blocking bracket. The air blocking bracket is installed on the rectangular spline of the rear shell through the air blocking rectangular spline. The phase of seed cleaning can be adjusted by adjusting the relative angle between the air blocking rectangular spline and the rectangular spline of the rear shell.

9. A method for filling a pneumatic seed meter, characterized in that: The pneumatic seed metering device according to any one of claims 1 to 8 is used for positive pressure airflow assisted seed filling, comprising the following steps: By adjusting the direction of the positive pressure airflow, the resistance of the seed filling area is reduced. The spiral guide mechanism changes the straight airflow entering the positive pressure chamber into a spiral airflow, and the spiral airflow is dispersed in the positive pressure chamber along the radial direction. The rotation direction is consistent with the seed disc, so that the airflow direction is opposite to the resistance direction during operation, thereby improving the seed filling capacity. as well as The adhesion of seeds is increased by increasing the air pressure difference on both sides of the seed hole. The seed hole is set to a double-structure hole type of circular hole and elliptical hole to improve the airtightness of the seed hole when the seeds are in different pressure attachment postures and reduce the effective gap area.

10. A high-speed precision seed drill, characterized in that: The invention comprises the pneumatic seed metering device according to any one of claims 1 to 8, and adopts the seed filling method according to claim 9 to perform positive pressure airflow assisted seed filling.

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