A millet precision seeder seed dispenser

Abstract

This utility model belongs to the field of mechanized sowing technology, specifically relating to a millet precision seeder seed metering device; it includes a housing and a seed metering disc, the seed metering disc being installed inside the housing and connected to a rotating shaft; the seed metering disc divides the interior of the housing into a first chamber and a second chamber; suction holes are distributed on the seed metering disc, connecting the first and second chambers; a negative pressure air chamber is provided in the second chamber, continuously covering part of the suction holes; an inlet and an outlet are opened on the housing, connecting the first chamber; a bristle barrier is provided between the inlet and outlet in the first chamber, dividing the first chamber into a storage area and a delivery area; the rotating shaft can drive the seed metering disc to rotate, and after the suction holes on the seed metering disc enter the negative pressure air chamber, they can adsorb single millet seeds in the storage area; after the suction holes leave the negative pressure air chamber, the single millet seeds detach from the suction holes and are discharged from the outlet; it adopts the principle of air suction seed metering, adsorbing seeds through the negative pressure air chamber and suction holes, avoiding direct contact and friction of mechanical seed metering devices.

Description

Technical Field

[0001] This utility model belongs to the field of mechanized sowing technology, specifically relating to a millet precision seeder seed metering device. Background Technology

[0002] Agricultural machinery has not only greatly liberated manpower but also significantly reduced sowing costs, leading to increasing acceptance among farmers. In millet sowing, seed arrangement and placement are the most crucial aspects. According to agronomic requirements, sowing must be strictly controlled within a short period, focusing on seed quantity, precision, spacing between plants, and uniformity of distribution. However, millet possesses inherent physical characteristics such as small size, light weight, and fragile husks. Currently, millet sowing methods primarily rely on traditional small-scale manual planting and mechanized row seeding, which can easily lead to problems like missed sowing, double sowing, and uneven sowing, affecting planting efficiency. Precision sowing technology can precisely control seed spacing and quantity, significantly improving seed utilization, avoiding waste, and ensuring even seed distribution. This provides seedlings with sufficient light, water, and nutrients, resulting in uniform and robust seedlings, laying the foundation for high yields. Furthermore, precision sowing eliminates the need for extensive thinning due to uniform emergence, greatly saving labor and costs.

[0003] Currently, mechanical seed metering devices are structurally classified into hole wheel type, shaped hole wheel type, and scoop type, etc. Mechanical seed metering devices have a simple structure, low cost, and are easy to maintain, and can meet the requirements of precision sowing. However, they cause significant wear and tear on seeds. Therefore, it is necessary to design a seed metering device that can reduce seed breakage rate, missed sowing rate, and reseeding rate. Utility Model Content

[0004] This invention aims to solve the problem of severe wear and tear on seeds caused by mechanical seed metering devices.

[0005] This utility model provides the following technical solution: a millet precision seeder seed metering device, comprising a housing and a seed metering disc, wherein the seed metering disc is installed inside the housing and connected to a rotating shaft extending into the housing; the seed metering disc divides the interior of the housing into a first chamber and a second chamber; The seed metering disc has suction holes arranged in a circular array around the rotating shaft, connecting the first and second chambers; the second chamber is equipped with a negative pressure air chamber that continuously covers part of the suction holes; The shell has an inlet and an outlet that connect to the first chamber. Inside the first chamber, there are bristles between the inlet and the outlet. The bristles divide the first chamber into a storage area and a delivery area. The bristles are used to prevent the seeds in the storage area from entering the delivery area. The rotating shaft can drive the seed metering disc to rotate. After the suction hole on the seed metering disc enters the negative pressure air chamber, it can adsorb the single grain of seed in the storage area. After the suction hole leaves the negative pressure air chamber, the single grain of seed is detached from the suction hole and discharged from the outlet.

[0006] Furthermore, a freely rotatable stirring impeller is provided in the storage area of ​​the first chamber, and a pair of internal meshing gears are provided between the seed metering disc and the stirring impeller, so that the rotation of the seed metering disc drives the rotation of the stirring impeller.

[0007] Furthermore, in the first chamber, a scraper is provided in the storage area close to the seed metering tray. The scraper is parallel to the seed metering tray and is connected to the shell through a support rod.

[0008] Furthermore, a seed cleaning wheel is installed in the second chamber, and the seed cleaning wheel is located outside the negative pressure air chamber; the axle of the seed cleaning wheel is connected to the swing arm, the swing arm is hinged to the housing, and a spring is connected between the swing arm and the housing. The spring gives the swing arm pressure to press the seed cleaning wheel against the seed dispensing plate. Seed cleaning teeth are distributed on the circumference of the seed cleaning wheel, and the spacing of the seed cleaning teeth matches the spacing of the suction holes.

[0009] Furthermore, in the direction of rotation of the seed metering disc, a raised baffle is provided on the side of the seed metering disc located in the first chamber in front of the suction hole.

[0010] Furthermore, the bottom of the first chamber has an vent, and the shell is connected to a removable cover plate that seals the vent.

[0011] Furthermore, the housing includes a left half-shell located on the first chamber side and a right half-shell located on the second chamber side, the left half-shell and the right half-shell being connected by bolts.

[0012] Furthermore, an arc-shaped negative pressure chamber is provided on the right half of the shell.

[0013] Furthermore, the scraper has serrated blades.

[0014] Furthermore, the blades of the stirring impeller are rubber blades.

[0015] Compared with the prior art, the advantages of this utility model are: This utility model provides a millet precision seeder seed metering device that adopts the principle of air suction seed metering. It adsorbs seeds through a negative pressure chamber and suction holes, avoiding direct contact and friction with mechanical seed metering devices, significantly reducing mechanical damage to seeds during adsorption and transport. The negative pressure chamber precisely controls the adsorption effect of the suction holes, with each hole adsorbing only one seed unit. Combined with the assistance of a seed cleaning wheel and bristles, it effectively prevents double-seeding and missed seeding, ensuring accurate seed spacing and seeding rate, and uniform distribution. The mixing impeller and scraper prevent seeds from accumulating or clogging in the storage area, ensuring smooth seed flow. The baffle design prevents seeds from prematurely falling off during adsorption, further improving the stability of seed metering. Attached Figure Description

[0016] Figure 1 External three-dimensional structure of the seed metering device for millet precision seeders Figure 1 ; Figure 2 This is an external front view of the seed metering device for a millet precision seeder. Figure 3 External three-dimensional structure of the seed metering device for millet precision seeders Figure 2 ; Figure 4 This is a schematic diagram of the first chamber; Figure 5 A schematic diagram of the left half of the shell being opened (the left half of the shell is facing forward). Figure 6 A schematic diagram of the left half of the shell being opened (the left half of the shell is in the reverse position); Figure 7 This is a schematic diagram showing the seed metering tray located on the side of the first chamber. Figure 8 A schematic diagram showing the opening of the right half of the shell; Figure 9 This is a schematic diagram showing the seeding tray located on the side of the second chamber.

[0017] In the diagram: 1-Shell; 1.1-Left half-shell; 1.2-Right half-shell; 2-Seed metering disc; 2.1-Suction hole; 2.2-Baffle bar; 3-Rotating shaft; 4-Negative pressure chamber; 5-Feed inlet; 6-Discharge outlet; 7-Baffle brush bristles; 8-Agitating impeller; 9-Gear ring; 10-Scraper; 11-Support rod; 12-Seed cleaning wheel; 12.1-Seed cleaning teeth; 13-Swing arm; 14-Connecting rod; 15-Cover plate. Detailed Implementation

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] like Figure 1 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 As shown: A millet precision seeder seed metering device includes a housing 1 and a seed metering disc 2. The seed metering disc 2 is installed inside the housing 1 and connected to a rotating shaft 3 extending into the housing 1. The seed metering disc 2 divides the interior of the housing 1 into a first chamber and a second chamber. The seed metering disc 2 has suction holes 2.1 arranged in a ring around the rotating shaft 3, connecting the first chamber and the second chamber; the second chamber is provided with a negative pressure air chamber 4 that continuously covers part of the suction holes; The shell 1 has an inlet 5 and an outlet 6 that connect to the first chamber. Inside the first chamber, there is a bristle 7 between the inlet 5 and the outlet 6. The bristle 7 divides the first chamber into a storage area and a delivery area. The bristle 7 is used to prevent the seeds in the storage area from entering the delivery area. The rotating shaft 3 can drive the seed metering disc 2 to rotate. After the suction hole 2.1 on the seed metering disc 2 enters the range of the negative pressure chamber 4, it can adsorb the single grain of rice in the storage area. After the suction hole 2.1 leaves the negative pressure chamber 4, the single grain of rice is detached from the suction hole 2.1 and discharged from the outlet 6.

[0020] The seed metering disc 2 uses negative pressure to adsorb and release the grain seeds. The suction holes 2.1 on the disc surface adsorb the grain seeds onto the seed metering disc 2. The grain seeds are moved to the delivery area by rotation. When the negative pressure disappears, the grain seeds fall with gravity and are evenly distributed in the soil broken by the furrow opener according to a fixed plant spacing, thus realizing the entire seed metering process.

[0021] The diameter of the seed metering disc 2 is directly proportional to the number of suction holes 2.1. As the diameter of the seed metering disc 2 increases, the number of suction holes 2.1 that can be arranged on its surface increases accordingly. Under the condition of constant tractor operating speed, a larger diameter seed metering disc 2 can operate at a lower speed, thereby prolonging the residence time of the seeds in the seed suction area and significantly reducing the probability of missed sowing. However, increasing the diameter of the seed metering disc 2 also has certain limitations: on the one hand, it will lead to a corresponding increase in the size of the matching air chamber, thereby increasing the power requirement of the external fan and affecting the overall energy efficiency of the machine. Therefore, the diameter of the seed metering disc 2 in this embodiment is 200mm.

[0022] The thickness of the seed metering disc 2 is also an important factor affecting the seed metering quality. The thickness of the seed metering disc 2 directly determines the negative pressure intensity at the suction hole 2.1. If the thickness of the seed metering disc 2 is too large, the negative pressure at the suction hole 2.1 will be too small, and the grains will not be adsorbed on the suction hole 2.1, resulting in missed sowing. If the thickness of the seed metering disc 2 is too small, the negative pressure at the suction hole 2.1 will be too high, which will not be able to sow smoothly and may adsorb multiple grains of grain, resulting in inaccurate sowing. In this embodiment, the thickness of the seed metering disc is 5mm.

[0023] The diameter of the suction orifice 2.1 is a key parameter affecting seed dispensing performance, and its size directly impacts the negative pressure adsorption effect. An excessively large orifice diameter significantly reduces the local negative pressure intensity, leading to insufficient seed adsorption and missed seeding; conversely, while an excessively small orifice diameter enhances adsorption, it can cause multiple seeds to be adsorbed simultaneously, increasing the risk of reseeding. Therefore, a reasonable design for the suction orifice 2.1 diameter must maintain sufficient negative pressure intensity while ensuring adsorption of a single seed. The diameter of the suction orifice 2.1 needs to be designed based on the size of the seed, and is calculated as follows: (3-1) In the formula: w is the diameter of the grain seed, in mm.

[0024] Furthermore, the suction hole 2.1 is located in the first chamber and has a chamfered opening design to accommodate the differences in grain size among different types of grains.

[0025] The number of suction holes 2.1 on the seed metering disc 2 is a crucial parameter determining sowing quality, significantly impacting the uniformity of seed spacing and operational efficiency. Under constant tractor speed conditions, increasing the number of suction holes 2.1 reduces the rotational speed of the seed metering disc 2, prolonging the seed residence time in the storage area, thereby increasing the seed filling rate and reducing missed sowing. However, when the suction holes 2.1 are arranged too densely, the airflow field between adjacent holes interferes, affecting the adsorption effect of individual seeds and significantly increasing the power consumption of the external fan. Conversely, insufficient suction holes 2.1 force the seed metering disc 2 to operate at high speed, resulting in insufficient residence time in the storage area, and some suction holes 2.1 failing to effectively adsorb seeds, leading to an increased missed sowing rate. Therefore, a reasonable design for the number of suction holes 2.1 needs to balance operational efficiency and energy economy while ensuring sowing quality. In this embodiment, the number of suction holes 2.1 is 27.

[0026] In terms of material selection, in this embodiment, the seed metering disc 2 is made of cast iron with a density of 7200 kg / m³. This material not only has good mechanical strength and wear resistance, but also effectively extends the overall service life of the seed metering device.

[0027] After the seeds enter the first chamber through the feed inlet 5, they gather in the storage area. Due to the small size of the seeds, they may stick together, which is not conducive to the adsorption of seeds by the suction holes 2.1 and affects the seed metering performance. A freely rotatable stirring impeller 8 is installed in the storage area of ​​the first chamber. A pair of internally meshing gears are installed between the seed metering disc 2 and the stirring impeller 8. The rotation of the seed metering disc 2 drives the stirring impeller 8 to rotate. Specifically, the stirring impeller 8 is rotatably mounted on the connecting rod 14 on the housing 1. A gear 8.1 is installed on the stirring impeller 8, and a gear ring 9 concentric with the rotating shaft 3 is installed on the seed metering disc 2. The gear 8.1 meshes with the gear ring 9. When the seed metering disc 2 rotates, it drives the gear 8.1 to rotate through the gear ring 9. The gear 8.1 drives the stirring impeller 8 to rotate, dispersing the stuck seeds and making them more active, which is more conducive to the adsorption of seeds by the suction holes. The blades of the stirring impeller 8 are made of rubber to avoid damage to the seeds during the stirring process.

[0028] In the first chamber, a scraper 10 is installed in the storage area close to the seed metering tray 2. The scraper 10 is parallel to the seed metering tray 2 and is connected to the shell 1 by a support rod 11 to prevent the grain seeds from sticking to the seed metering tray 2. The scraper 10 has a serrated blade.

[0029] like Figure 8 , Figure 9As shown: A seed cleaning wheel 12 is provided in the second chamber, and the seed cleaning wheel 12 is located outside the negative pressure air chamber 4; the axle of the seed cleaning wheel 12 is connected to the swing arm 13, the swing arm 13 is hinged to the housing 1, and a spring is connected between the swing arm 13 and the housing 1. The spring gives the swing arm 13 pressure to press the seed cleaning wheel 12 against the seed dispensing disc 2. The spring can be a torsion spring connected to the hinge shaft of the swing arm 13, or a tension spring connected between the swing arm 13 and the housing 1. Seed cleaning teeth 12.1 are distributed on the circumference of the seed cleaning wheel 12, and the spacing of the seed cleaning teeth 12.1 matches the spacing of the suction holes 2.1.

[0030] When seeds are adsorbed onto the suction hole 2.1, some irregularly shaped seeds may become stuck, preventing successful sowing and causing missed sowing. Furthermore, the stuck seeds in the suction hole 2.1 will continue to operate with the rotation of the seed metering disc 2, severely affecting the sowing quality. To address this, a seed cleaning wheel 12 was designed to effectively remove stuck seeds and improve sowing quality. The seed cleaning wheel 12 rotates with the seed metering disc 2, and its cylindrical cleaning teeth 12.1 engage with the suction hole 2.1, discharging the stuck seeds and allowing the suction hole 2.1 to smoothly proceed with the next round of adsorption. To ensure that the cleaning teeth 12.1 on the cleaning wheel 12 can accurately engage with the suction hole 2.1 each time, the opening of the suction hole 2.1 located in the second chamber is designed as a square opening that transitions to a round opening with a chamfer. The square opening initially increases the engagement range with the cleaning teeth 12.1. Then, the cleaning teeth 12.1 slide into the round opening along the chamfer and push the seeds on the other side, ensuring that the cleaning teeth 12.1 accurately extend into the suction hole 2.1. Furthermore, the chamfered structure increases the extension range of the cleaning teeth 12.1, allowing them to reach the seeds on the other side.

[0031] Along the rotation direction of the seed metering disc 2, a raised baffle 2.2 is provided on the side of the seed metering disc 2 located in the first chamber in front of the suction hole 2.1; to prevent the seeds adsorbed by the suction hole 2.1 from being swept off when passing through the bristles 7.

[0032] like Figure 3 , Figure 5 As shown: The bottom of the first chamber has an air vent, and the shell 1 is connected to a detachable cover plate 15 that closes the air vent. After opening the cover plate 15, the unsown grain seeds can be vented.

[0033] like Figure 2 As shown: the housing 1 includes a left half-shell 1.1 located on the first chamber side and a right half-shell 1.2 located on the second chamber side. The left half-shell 1.1 and the right half-shell 1.2 are connected by bolts; this facilitates maintenance and repair.

[0034] An arc-shaped negative pressure chamber 4 is provided on the right half shell 1.2. The negative pressure chamber 4 is connected to an external fan through an air pipe. A sealing ring is installed on the edge of the negative pressure chamber 4 on the right half shell 1.2. The sealing ring slides in contact with the surface of the seed metering tray 2 to reduce negative pressure loss.

[0035] During millet sowing, the millet seeds enter the first chamber through the seed delivery pipe at the bottom of the seed box and the feed inlet 5 of the seed metering device. Due to the interception effect of the bristles 7, the millet seeds gather in the storage area of ​​the first chamber. Under the negative pressure of the negative pressure air chamber 4 in the second chamber, the suction holes 2.1 on the seed metering plate 2 adsorb and grab the millet seeds. When the motor drives the rotating shaft 3, the shaft 3 rotates the seed metering disc 2. The seed metering disc 2 carries the millet through the suction hole 2.1 and passes through the bristles 7. Millet not sucked by the suction hole 2.1 is still blocked by the bristles 7 and stored in the storage area. The baffle 2.2 in front of the suction hole 2.1 further prevents the bristles 7 from sweeping the millet off. As the seed metering disc 2 continues to rotate, when the suction hole 2.1 leaves the negative pressure chamber 4, the negative pressure disappears, and the millet can fall off the seed metering disc 2 under its own weight. The cleaning teeth 12.1 of the cleaning wheel 12 can push the millet, ensuring that no millet is stuck in the suction hole 2.1. The fallen millet is discharged from the discharge port 6 and put into the seed furrow, completing the sowing operation. This seed metering device realizes the agronomic requirement of single-grain precision sowing, effectively improving sowing quality and operation efficiency.

[0036] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A seed metering device for a millet precision seeder, characterized in that: It includes a housing (1) and a seed metering disc (2), the seed metering disc (2) is installed inside the housing (1) and connected to a rotating shaft (3) extending into the housing (1); the seed metering disc (2) divides the interior of the housing (1) into a first chamber and a second chamber; The seeding tray (2) has suction holes (2.1) arranged in a ring around the rotating shaft (3) that connect the first chamber and the second chamber; the second chamber is provided with a negative pressure air chamber (4) that continuously covers part of the suction holes. The shell (1) has an inlet (5) and an outlet (6) that connect the first chamber. In the first chamber, there is a bristle (7) between the inlet (5) and the outlet (6). The bristle (7) divides the first chamber into a storage area and a delivery area. The bristle (7) is used to prevent the grain seeds in the storage area from entering the delivery area. The rotating shaft (3) can drive the seed metering plate (2) to rotate. After the suction hole (2.1) on the seed metering plate (2) enters the negative pressure air chamber (4), it can adsorb the single grain seeds in the storage area. After the suction hole (2.1) leaves the negative pressure air chamber (4), the single grain seeds are removed from the suction hole (2.1) and discharged from the outlet (6).

2. The millet precision seeder seed metering device according to claim 1, characterized in that: The first chamber is equipped with a freely rotatable stirring impeller (8) in the storage area. A pair of internal meshing gears are provided between the seed metering disc (2) and the stirring impeller (8). The rotation of the seed metering disc (2) drives the stirring impeller (8) to rotate.

3. The millet precision seeder seed metering device according to claim 2, characterized in that: The first chamber has a scraper (10) placed close to the seed metering tray (2) in the storage area. The scraper (10) is parallel to the seed metering tray (2) and is connected to the shell (1) by a support rod (11).

4. A millet precision seeder seed metering device according to any one of claims 1 to 3, characterized in that: The second chamber is provided with a seed cleaning wheel (12), which is located outside the negative pressure air chamber (4). The axle of the seed cleaning wheel (12) is connected to the swing arm (13), which is hinged to the housing (1). A spring is connected between the swing arm (13) and the housing (1). The spring gives the swing arm (13) pressure to press the seed cleaning wheel (12) onto the seed dispensing plate (2). Seed cleaning teeth (12.1) are distributed on the circumference of the seed cleaning wheel (12), and the spacing of the seed cleaning teeth (12.1) matches the spacing of the suction holes (2.1).

5. The millet precision seeder seed metering device according to claim 1, characterized in that: In the direction of rotation of the seed metering disc (2), a raised baffle (2.2) is provided in front of the suction hole (2.1) on the side of the seed metering disc (2) located in the first chamber.

6. The millet precision seeder seed metering device according to claim 1, characterized in that: The bottom of the first chamber has an air vent, and the shell (1) is connected to a removable cover plate (15) that closes the air vent.

7. The millet precision seeder seed metering device according to claim 1, characterized in that: The housing (1) includes a left half-shell (1.1) located on the first chamber side and a right half-shell (1.2) located on the second chamber side, and the left half-shell (1.1) and the right half-shell (1.2) are connected by bolts.

8. The millet precision seeder seed metering device according to claim 7, characterized in that: The right half shell (1.2) is provided with an arc-shaped negative pressure air chamber (4).

9. A millet precision seeder seed metering device according to claim 3, characterized in that: The scraper (10) has a serrated blade.

10. A millet precision seeder seed metering device according to claim 2, characterized in that: The blades of the impeller (8) are rubber blades.

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