Seed ejection pipeline for seed-metering device, seed-metering device and seeding device

Abstract

The invention discloses a seed injection pipeline for a seed-metering device, the seed-metering device and a seeding device, and the seed injection pipeline is provided with a seed inlet and a seed outlet; the seed injection pipeline comprises a main pipe part and a branch pipe part; the seed outlet is positioned at one end of the main pipe part, and the other end of the main pipe part is an airflow inlet for introducing positive pressure airflow; the main pipe part is provided with a first thick pipe section, a contraction section, a thin pipe section, an expansion section and a second thick pipe section which are sequentially arranged from the airflow inlet; the seed inlet is positioned at one end of the branch pipe part, and the other end of the branch pipe part is communicated with the thin pipe section; and the branch pipe part is obliquely arranged relative to the main pipe part. According to the invention, on one hand, the reliability of seed metering is improved, seed blockage is avoided, on the other hand, circumferential wrapping force is formed on the seeds by utilizing the pressure difference of the airflow field in the path space of the long and narrow circular pipe, the coercing constraint is realized, the collision contact between the seeds and the pipe wall is inhibited, the problem of gathering and seed guiding caused by track deviation is solved, and the precision of planting distance is improved.

Description

Technical Field

[0001] The invention relates to the technical field of agricultural sowing, and in particular to a seed ejection pipe for a seed meter, a seed meter and a sowing device. Background Art

[0002] The seed meter plays a vital role in modern agricultural production. It is one of the core components of the seeder and directly affects the planting quality, growth uniformity and final yield of crops. Accurate seed discharge can ensure that each plant has enough growth space and resources, thereby promoting healthy growth and increasing yields. An efficient seed meter can ensure that seeds are accurately implanted in the soil according to the preset spacing and depth, reduce seed waste, and adapt to the requirements of different crop types and field conditions.

[0003] The applicant's prior application CN117223443A provides a typical pneumatic seed metering device, which introduces air flow to the front side of the seeding disk so that the seed suction holes on the seeding disk generate suction to absorb seeds. After the adsorbed seeds reach the seeding holes, the seeds enter the seeding holes, and the air flow overflowing into the seeding holes promotes the discharge of the seeds. In this seed metering device, although the air flow can promote the discharge of seeds, the precision control of seed discharge is poor. The seeds are prone to collide with the wall of the seeding tube, resulting in dislocation of the collision. In addition, frequent collisions between the seeds and the tube wall during the discharge process will affect the discharge speed and discharge rhythm of the seeds, and affect the plant spacing.

[0004] Another prior application of the applicant, CN116326290A, provides a ring-gap-injected seed airflow guide device and method for high-speed precision seeding operations. In this patent, a vacuum-type precision seeding device, a seed blowing tube, and a special ring-gap-injected structure are used to form a negative pressure zone at the seeding position using positive pressure airflow to achieve stable seed injection and transportation, reduce the collision between seeds and the inner wall of the seed guide tube, and cooperate with the seed pressing wheel to ensure accurate positioning of seeds into the soil, thereby improving the uniformity and quality of seeding under high-speed operations. However, the injection structure in this patent is relatively complex, and the processing and assembly are relatively complex, and the cost of use is high. Summary of the invention

[0005] Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides a seed ejection pipe for a seed meter, a seed meter and a sowing device which can improve seeding stability and have low cost.

[0006] Technical solution: To achieve the above purpose, the seed ejection pipe for the seed metering device of the present invention has a seed inlet and a seed outlet;

[0007] The seed ejection pipeline comprises a main pipe part and a branch pipe part; the seed outlet is located at one end of the main pipe part, and the other end of the main pipe part is an air flow inlet for introducing positive pressure air flow;

[0008] The main pipe section comprises a first thick pipe section, a contraction section, a thin pipe section, an expansion section and a second thick pipe section which are arranged in sequence from the air flow inlet;

[0009] The seed inlet is located at one end of the branch pipe portion, and the other end of the branch pipe portion is connected to the thin tube segment;

[0010] The branch pipe part is arranged obliquely relative to the main pipe part, so that when the seeds enter the main pipe part through the branch pipe part, the movement direction of the seeds has a component along the direction of the airflow in the main pipe part.

[0011] Furthermore, the diameter of the first thick pipe section is larger than the diameter of the second thick pipe section.

[0012] Furthermore, the contraction section and the expansion section are both conical.

[0013] Furthermore, the main pipe section further includes a curved pipe section connected to the second thick pipe section, and the seed outlet is located at the end of the curved pipe section.

[0014] During operation, the positive pressure airflow enters the main pipe section from the air flow inlet. In the process of the airflow entering the thin pipe section from the first thick pipe section via the contraction section, the dispersed airflow gathers due to the smaller pipe diameter, the airflow velocity increases, and the flow field pressure decreases. After the airflow enters the second thick pipe section from the thin pipe section via the expansion section, the flow velocity slows down and the flow field pressure increases. Therefore, the air pressure in the thin pipe section is the lowest, thereby generating a negative pressure flow field in the branch pipe section. The negative pressure flow field can suck the seeds transported to the seed inlet into the branch pipe section. The seeds enter the main pipe section from the branch pipe section, and are finally discharged from the seed outlet into the soil under the thrust of the airflow field in the main pipe section.

[0015] The cross-section of the main pipe part is circular. Since the airflow field in the narrow circular pipe space has the characteristics of low velocity and high pressure close to the pipe wall, and high velocity and low pressure in the center of the pipe, it has the effect of entrainment, restraint and inhibition on the seeds, making the seeds move in the center relative to the main pipe part, preventing the seeds from colliding with the pipe wall, and improving the speed and direction consistency of the ejected seeds.

[0016] A seed meter comprises an outer shell and a seed disk located in the outer shell, the seed disk has seed suction holes arranged in a circumferential array, and also comprises a seed box for supplying seeds into the outer shell; there is a pressure difference between the front and back sides of the seed disk so that the seed suction holes can generate adsorption force; the above-mentioned seed introduction pipe is fixed on the outer shell, the branch pipe portion of the seed introduction pipe extends into the outer shell, and the seed inlet is placed on the movement path of the seed suction holes.

[0017] In order to create an air pressure difference between the front and back sides of the seeding disc, the first method is to make the front side of the housing closed and the back side ventilated (that is, the back side has vent holes connected to the atmosphere), and then air is introduced to the front side of the seeding disc. The second method is to make the front side of the housing ventilated and the back side closed, and then air is extracted from the back side of the seeding disc.

[0018] Furthermore, a roller is rotatably mounted in the shell, and the roller is placed on the back side of the seeding disc and aligned with the seed inlet front and back.

[0019] With the above structure, when the seed disc rotates, each seed suction hole passes through the seed box in turn. Due to the pressure difference on the front and back sides of the seed suction hole, the seed suction hole generates an adsorption force to suck out the seeds from the seed box and move the seeds to the position of the seed inlet. The roller acts on the back side of the seed suction hole, so that the pressure difference on both sides of the seed suction hole disappears, the seeds fall from the seed suction hole and are sucked into the branch pipe part, and then discharged from the seed outlet through the main pipe part.

[0020] A sowing device comprises the above-mentioned seed metering device and a seed pressing wheel, wherein the seed pressing wheel is arranged at the rear side of the seed outlet. During operation, the seeds ejected from the seed outlet are quickly rolled into the soil under the action of the seed pressing wheel, thereby avoiding the problem of bouncing out of position.

[0021] Beneficial effects: The seed ejection pipe for the seed meter, the seed meter and the sowing device of the present invention have the following beneficial effects:

[0022] (1) Instead of simply relying on the airflow overflowing from the seed metering device shell to promote seeding, the seed ejection pipe is used to improve the reliability of seeding and avoid seed blockage. On the other hand, the airflow traction and transportation effect increases the seed migration speed, realizes the accelerated separation of seeds, expands the distance between adjacent seeds, and reduces the time for seeds to pass through the seed guide tube. The pressure difference of the airflow field in the narrow circular tube path space is used to form a circumferential wrapping force on the seeds, realizes the entrainment constraint, inhibits the collision and contact between the seeds and the tube wall, solves the problem of seed aggregation caused by trajectory deviation, and improves the accuracy of planting spacing.

[0023] (2) The one-piece seed ejection pipe structure can achieve similar technical effects as the prior application CN116326290A, but has a simple structure, low production cost, and does not require assembly, thereby reducing the cost of use. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a combined structural diagram of a seed ejection pipe, a seed plate and a roller for a seed meter;

[0025] Figure 2 It is the combined structure diagram of the ejection pipe and the seeding disc;

[0026] Figure 3 for Figure 2 Middle AA section structure diagram;

[0027] Figure 4 This is a structural diagram of the seed meter;

[0028] Figure 5 A structural diagram of the configuration mechanism;

[0029] Figure 6 This is a structural diagram of the seeding device.

[0030] In the figure: 1-main pipe part; 1a-first thick pipe section; 1b-contraction section; 1c-thin pipe section; 1d-expansion section; 1e-second thick pipe section; 1f-bend pipe section; 2-branch pipe part; a-seed inlet; b-seed outlet; c-air flow inlet; 3-housing; 4-seed plate; 4a-seed suction hole; 5-seed box; 6-roller; 7-seed pressing wheel; 8-air pump; 9-configuration mechanism; 91-cylinder; 91a-air hole; 91b-air inlet connection end; 92-piston; 92a-air outlet connection end; 93-sleeve; 94-spring. DETAILED DESCRIPTION

[0031] The present invention will be further described below in conjunction with the accompanying drawings.

[0032] like Figure 1 and Figure 2 The seed ejection pipe for the seed metering device has a seed inlet a and a seed outlet b;

[0033] The seed injection pipeline includes a main pipe part 1 and a branch pipe part 2; the seed outlet b is located at one end of the main pipe part 1, and the other end of the main pipe part 1 is an airflow inlet c for introducing positive pressure airflow;

[0034] like Figure 3 As shown, the main pipe section 1 comprises a first thick pipe section 1a, a contraction section 1b, a thin pipe section 1c, an expansion section 1d and a second thick pipe section 1e which are arranged in sequence from the air flow inlet c;

[0035] The seed inlet a is located at one end of the branch pipe portion 2, and the other end of the branch pipe portion 2 is connected to the thin tube segment 1c;

[0036] The branch pipe part 2 is arranged obliquely relative to the main pipe part 1 , so that when the seeds enter the main pipe part 1 through the branch pipe part 2 , the movement direction of the seeds has a component along the airflow direction in the main pipe part 1 .

[0037] Preferably, the diameter of the first thick pipe section 1 a is larger than the diameter of the second thick pipe section 1 e.

[0038] Preferably, the contraction section 1b and the expansion section 1d are both conical.

[0039] Preferably, the main pipe section 1 further comprises a curved pipe section 1f connected to the second thick pipe section 1e, and the seed outlet b is located at the end of the curved pipe section 1f.

[0040] During operation, the positive pressure airflow enters the main pipe section 1 from the airflow inlet c. In the process of the airflow entering the thin pipe section 1c from the first thick pipe section 1a via the contraction section 1b, the dispersed airflow gathers due to the smaller pipe diameter, the airflow velocity increases, and the flow field pressure decreases. After the airflow enters the second thick pipe section 1e from the thin pipe section 1c via the expansion section 1d, the flow velocity slows down and the flow field pressure increases. Therefore, the air pressure in the thin pipe section 1c is the lowest, so that the branch pipe section 2 generates a negative pressure flow field. The negative pressure flow field can suck the seeds transported to the seed inlet a into the branch pipe section 2. The seeds enter the main pipe section 1 from the branch pipe section 2, and are finally discharged from the seed outlet b into the soil under the thrust of the airflow field in the main pipe section 1.

[0041] The cross-section of the main pipe part 1 is circular. Since the airflow field in the narrow circular tube space has the characteristics of low velocity and high pressure near the tube wall, and high velocity and low pressure in the center of the tube, it has the effect of entrainment, restraint and inhibition on the seeds, so that the seeds move in the center relative to the main pipe part 1, preventing the seeds from colliding with the tube wall, and improving the speed and direction consistency of the ejected seeds.

[0042] The present invention also provides a seed metering device, such as Figure 4 As shown, it includes an outer shell 3 and a seed plate 4 located in the outer shell 3, the seed plate 4 has seed suction holes 4a arranged in a circumferential array, and also includes a seed box 5 for supplying seeds into the outer shell 3; there is a pressure difference between the front and back sides of the seed plate 4 so that the seed suction holes 4a can generate adsorption force; the above-mentioned seed introduction pipe is fixed on the outer shell 3, the branch pipe part 2 of the seed introduction pipe extends into the outer shell 3, and the seed inlet a is placed on the movement path of the seed suction holes 4a.

[0043] In order to create an air pressure difference between the front and back sides of the seeding disk 4, the first method is to make the front side of the housing 3 closed and the back side ventilated (that is, the back side has vent holes connected to the atmosphere), and introduce airflow to the front side of the seeding disk 4. The second method is to make the front side of the housing 3 ventilated and the back side closed, and extract airflow from the back side of the seeding disk 4.

[0044] The second method mentioned above is adopted in this embodiment, and air is extracted from the reverse side of the outer shell 3 by using an air pump 8, and the extracted airflow is introduced into the airflow inlet c of the seed injection pipe. Specifically, the air extraction port of the air pump 8 is connected to the reverse side of the outer shell 3, and the air outlet of the air pump 8 is connected to a configuration mechanism 9. The configuration mechanism 9 has two air outlet paths, one of which is connected to the airflow inlet c of the seed injection pipe, and the other leads to the atmosphere.

[0045] like Figure 5As shown, the configuration mechanism 9 includes a cylinder 91 with a circular channel inside, a piston 92 that can slide relative to the circular channel of the cylinder 91, and a sleeve 93 that can slide relative to the outer wall of the cylinder 91. The outer wall of the cylinder 91 has multiple groups of air holes 91a distributed along its axial direction; the cylinder 91 and the piston 92 respectively have an air inlet connection end 91b connected to the air pump 8 and an air outlet connection end 92a connected to the air flow inlet c; a spring 94 is provided between the piston 92 and the cylinder 91, and the sleeve 93 can move with the piston 92. The above structure can maintain the stability of the gas pressure provided to the airflow inlet c. Initially, the sleeve 93 blocks the outside of the air hole 91a. When the airflow pressure provided by the air outlet of the air pump 8 is too high, the air pressure pushes the piston 92 to overcome the elastic force of the spring 94, and the piston 92 drives the sleeve 93 to move. The sleeve 93 releases the blockage of a part of the air holes 91a, so that more air holes 91a participate in the pressure relief, and the airflow pressure in the cylinder 91 is reduced; when the airflow pressure is reduced, the spring 94 pushes the piston 92 to move, and the piston 92 drives the sleeve 93 so that the sleeve 93 blocks a part of the air holes 91a, reducing the airflow leaking out. In this way, the air pressure stability can be guaranteed, stable seeding can be achieved, and the sowing accuracy can be improved.

[0046] Preferably, a roller 6 is rotatably installed in the housing 3, and the roller 6 is placed on the back side of the seeding disc 4 and is aligned front to back with the seed inlet a.

[0047] With the above structure, when the seed disc 4 rotates, each seed suction hole 4a passes through the seed box 5 in sequence. Due to the pressure difference between the front and back sides of the seed suction hole 4a, the seed suction hole 4a generates an adsorption force to suck out the seeds from the seed box 5 and move the seeds to the position of the seed inlet a. The roller 6 acts on the back side of the seed suction hole 4a, so that the pressure difference on both sides of the seed suction hole 4a disappears, and the seeds fall from the seed suction hole 4a and are sucked into the branch pipe part 2, and then discharged from the seed outlet b through the main pipe part 1.

[0048] Through the above-mentioned seed introduction pipeline, the conventional seed guidance mode relying solely on gravity and the mode of simply relying on the airflow overflowing from the seed metering device housing 3 to promote seeding are abandoned. Through the above-mentioned seed introduction pipeline, on the one hand, the reliability of seeding is improved to avoid seed blockage. On the other hand, the airflow traction and transportation effect increases the seed migration speed, realizes the accelerated separation of seeds, expands the distance between adjacent seeds, reduces the time for seeds to pass through the seed guide tube, and utilizes the pressure difference of the airflow field in the narrow circular tube path space to form a circumferential wrapping force on the seeds, realizes entrainment constraint, inhibits the collision and contact between seeds and the tube wall, solves the problem of aggregated seed guidance caused by trajectory deviation, and improves the accuracy of planting spacing.

[0049] The present invention also provides a sowing device, such as Figure 6As shown, it includes the above-mentioned seed metering device and also includes a seed pressing wheel 7, which is placed at the rear side of the seed outlet b. During operation, the seeds ejected from the seed outlet b are quickly rolled into the soil under the action of the seed pressing wheel, avoiding the problem of bouncing out of position.

[0050] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A seed ejection pipe for a seed metering device, comprising a seed inlet (a) and a seed outlet (b); characterized in that: The seed injection pipeline comprises a main pipe part (1) and a branch pipe part (2); the seed outlet (b) is located at one end of the main pipe part (1), and the other end of the main pipe part (1) is an airflow inlet (c) for introducing positive pressure airflow; The main pipe section (1) comprises a first thick pipe section (1a), a contraction section (1b), a thin pipe section (1c), an expansion section (1d) and a second thick pipe section (1e) which are arranged in sequence from the air flow inlet (c); The seed inlet (a) is located at one end of the branch pipe portion (2), and the other end of the branch pipe portion (2) is connected to the thin pipe section (1c); The branch pipe portion (2) is arranged obliquely relative to the main pipe portion (1).

2. The seed ejection pipe for a seed metering device according to claim 1, characterized in that: The diameter of the first thick pipe section (1a) is larger than the diameter of the second thick pipe section (1e).

3. The seed ejection pipe for a seed metering device according to claim 1, characterized in that: The contraction section (1b) and the expansion section (1d) are both conical.

4. The seed ejection pipe for a seed metering device according to claim 1, characterized in that: The main pipe section (1) further comprises a curved pipe section (1f) connected to the second thick pipe section (1e), and the seed outlet (b) is located at the end of the curved pipe section (1f).

5. A seed meter, comprising a housing (3) and a seeding disc (4) located in the housing (3), the seeding disc (4) having seed suction holes (4a) arranged in a circumferential array, and also comprising a seed box (5) for supplying seeds into the housing (3); there is a pressure difference between the front and back sides of the seeding disc (4); characterized in that, The shell (3) is fixed with the seed ejection pipe according to any one of claims 1 to 4, the branch pipe portion (2) of the seed ejection pipe extends into the shell (3), and the seed inlet (a) is placed on the movement path of the seed suction hole (4a).

6. The seed metering device according to claim 5, characterized in that: A roller (6) is rotatably mounted in the housing (3); the roller (6) is placed on the back side of the seeding disc (4) and is aligned front to back with the seed inlet (a).

7. A sowing device, characterized in that: It comprises the seed metering device as claimed in claim 5, and further comprises a seed pressing wheel (7), wherein the seed pressing wheel (7) is arranged at the rear side of the seed outlet (b).

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