Coating device for corn seed production

By improving the stirring mechanism and microwave heating technology, the problems of seed damage and uneven coating in the seed coating device have been solved, thereby improving the germination rate and storage stability and reducing energy consumption.

CN120959008AActive Publication Date: 2025-11-18BEIJING FENGJIE YIJIA AGRICULTURAL TECHNOLOGY CO LTD
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Patent Information

Application Number
CN202511171360.2
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2025-08-21
Publication Date
2025-11-18
Estimated Expiration
2045-08-21

AI Technical Summary

Technical Problem

Existing corn seed coating devices are prone to damage from hard impacts and violent collisions between seeds during the mixing process, resulting in a decrease in germination rate and poor coating effect.

Method used

The device employs a stirring mechanism design, including a first partition, a second partition, and a spiral pipe, combined with a microwave generator and a waveguide slot antenna, to ensure that the seeds rotate and tumble and are heated evenly, reducing seed damage; an air pump and heater provide controllable hot air drying, and a switching mechanism ensures airtightness.

Benefits of technology

It improves seed germination rate and storage stability, reduces seed damage, shortens drying cycle, and reduces energy consumption.

✦ Generated by Eureka AI based on patent content.

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Abstract

The invention relates to the technical field of corn seed coating equipment, in particular to a coating device for corn seed production, which comprises a bracket main body, a fixed frame mounted on the bracket main body, a jacket arranged in the fixed frame in a penetrating manner, a first cylinder and a second cylinder mounted at two ends of the jacket respectively, and a stirring mechanism, the stirring mechanism is mounted on the first cylinder and connected with the second cylinder, and the stirring mechanism continuously rolls while driving the seeds to rotate around the inner wall of the jacket; according to the stirring mechanism, through the design of the first separation barrel, the second separation barrel and the spiral first pipeline, seeds are driven to rotate around the inner wall of the clamping sleeve and roll continuously, and accumulation or omission of a coating material is avoided; the uniform heating of the microwave generator (20kHz frequency) and the waveguide slot antenna is combined, so that the coating layer is rapidly and consistently cured, the seed damage is reduced, and the germination rate and the storage stability are improved.
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Description

Technical Field

[0001] This invention relates to the field of corn seed coating equipment technology, specifically a coating device for corn seed production. Background Technology

[0002] Currently, corn seed coating operations commonly employ agitation-type coating devices. The core components of such devices typically include a mixing chamber and an internal mixing mechanism. In existing technologies, the most commonly used mixing mechanism is a rigid auger rod (screw conveyor rod) or a spiral mixing rod. Its working principle is as follows: a drive device rotates the mixing rod within the seed-filled mixing chamber, using the blades or spiral surface of the mixing rod to tumble and mix the seeds, while simultaneously spraying the coating agent onto the seed surface to achieve a uniform coating effect.

[0003] However, this coating device based on a rigid stirring rod has obvious technical defects in practical applications, mainly in the following two aspects: Hard impact damage between the stirring rod and the seeds: During the high-speed rotation of the stirring rod (especially the blade edges of the auger or spiral stirring rod), its hard metal or hard material surface inevitably comes into direct and violent physical contact and friction with the large number of corn seeds in the hopper. Corn seeds, especially their germ parts, are relatively fragile. This continuous hard impact can easily cause scratches and damage to the seed coat, and even mechanical damage to the germ. This physical damage is latent and may not be easily detected after coating, but it will significantly reduce seed viability, leading to a decrease in germination rate (seedling emergence rate) after subsequent sowing, directly affecting agricultural production efficiency. Excessive collisions between seeds due to agitation: Rigid agitators require significant mechanical force to move the seed swarm to achieve proper mixing. Under this strong agitation, the seed swarm does not flow uniformly and gently, but is violently agitated and scattered by the blades. This results in intense collisions and friction between seeds within the mixing chamber. This high-intensity collision exacerbates physical damage to the seed surface (adding to the damage caused by the agitator); furthermore, it significantly damages the coating film that has already begun to adhere to the seed surface. The coating film, whether forming or newly formed, is easily detached, peeled off, or becomes uneven under the intense collisions and friction between seeds, leading to a poorer coating effect.

[0004] In summary, the shortcomings of existing corn seed coating devices directly lead to two major problems: reduced seed germination rate and poor coating effect, which restrict the improvement of seed treatment quality and agricultural production efficiency. Therefore, there is an urgent need in this field for a coating device and mixing method that can effectively avoid or significantly reduce physical damage to seeds during the coating process, while ensuring uniform and firm adhesion of the coating agent. Summary of the Invention

[0005] To solve the above-mentioned technical problems, the present invention provides a coating device for corn seed production, including a support body, a fixing frame mounted on the support body, a sleeve passing through the fixing frame, and a first cylinder and a second cylinder respectively mounted at both ends of the sleeve, and further comprising: A stirring mechanism is installed on the first cylinder and connected to the second cylinder. The stirring mechanism drives the seeds to rotate around the inner wall of the jacket while continuously tumbling itself. A tilting mechanism is installed on the support body to drive the support body to tilt for subsequent material discharge.

[0006] Preferably, the stirring mechanism includes a first partition and a second partition installed inside the first cylinder and the second cylinder. There are multiple first partitions and second partitions, which are identical in shape and number. The side of the partitions that are far apart from each other is fan-shaped, and the side of the multiple first partitions or second partitions that are far apart from each other forms a complete circle. The side of the first partitions and second partitions that are close to each other is also circular. The first partitions and second partitions are connected by a first pipe. The number of first pipes is equal to the number of first partitions and is spiral-shaped. The stirring mechanism also includes a driving component installed on the support body. The driving component is used to drive the first partitions to rotate.

[0007] Preferably, the driving component includes a servo motor mounted on the support body, a gear mounted on the top of the servo motor, and a gear ring sleeved on the first partition cylinder, wherein the gear and the gear ring mesh with each other.

[0008] Preferably, a fixed seat is installed on the main body of the support, and a feed pipe is installed on the fixed seat. A sealed bearing is sleeved on the side of the first cylinder away from the second cylinder, and the inner wall of one end of the feed pipe is sleeved on the sealed bearing.

[0009] Preferably, the tilting mechanism includes a slide rail installed at the bottom of the support body, the slide rail being located on the side near the first partition cylinder, a slide rod slidably disposed inside the slide rail, a connecting block sleeved on the slide rod, a triangular plate disposed directly below the slide rail, rollers disposed at the bottom of the three corners of the triangular plate, a hydraulic rod mounted on the triangular plate, and the end of the hydraulic rod away from the triangular plate being fixed to the connecting block.

[0010] Preferably, the jacket is equipped with a switching mechanism for sealing or opening the second cylinder. The switching mechanism includes a support block installed on the jacket, a groove on the support block, a slider slidably disposed in the groove, a support rod through the slider, the support rod being U-shaped, a sealing cover installed on the second cylinder, and two hanging ears installed opposite each other on the sealing cover, the two hanging ears respectively sleeved on the two ends of the support rod.

[0011] Preferably, a conduit is installed through the sealed cover, and an air pump and a heater are installed on the sealed cover. The exhaust port of the air pump is connected to the conduit through a second pipe, passing through the heater. A partition is respectively provided on the first pipe near the first cylinder and the second cylinder. A third pipe is provided between the center of the two partitions and the side of the first cylinder and the second cylinder that is far away from each other. A plug-in quick connector is installed on the end of the conduit near the third pipe. A flow equalization plate is respectively provided on the first pipe near the first cylinder and the second cylinder, and the flow equalization plate is located between the two partitions.

[0012] Preferably, a microwave generator is provided at the end of the conduit away from the second partition, and a fourth pipe is provided at the output port of the microwave generator. The fourth pipe passes through the conduit, the third pipe near the second cylinder, and the flow equalization plate near the second cylinder. A resonant cavity is installed on the side of the flow equalization plate near the second cylinder away from the corresponding side partition. A waveguide slot antenna is connected to the resonant cavity. There are several waveguide slot antennas arranged in a ring array.

[0013] Preferably, the microwave generator emits at a frequency of 20 kHz.

[0014] Preferably, the jacket is fitted with buckles on both sides near the second partition, and the support legs of the main body of the bracket away from the triangular plate are polygonal in contact with the ground.

[0015] This invention has at least the following beneficial effects: 1. The stirring mechanism, through the design of the first partition, the second partition, and the spiral first pipe, drives the seeds to rotate around the inner wall of the jacket while continuously tumbling, thus avoiding the accumulation or leakage of coating material; combined with the uniform heating of the microwave generator (20kHz frequency) and the waveguide slot antenna, it ensures that the coating layer solidifies quickly and uniformly, reduces seed damage, and improves germination rate and storage stability.

[0016] 2. The air pump, heater, and microwave generator provide controllable hot air and microwave drying through components such as ducts and resonant cavities, enabling immediate drying of coated seeds; the switching mechanism (sealed cover, support rod) ensures airtightness, prevents heat loss, shortens the drying cycle, reduces energy consumption, and the overall structure of the device is compact and easy to maintain. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the structure of the present invention from a bottom view; Figure 3 For the present invention Figure 2 Schematic diagram of the structure at point A in the middle; Figure 4 For the present invention Figure 2 Schematic diagram of the structure at point B; Figure 5 This is a schematic diagram of the internal structure of the present invention; Figure 6 For the present invention Figure 5 Schematic diagram of the structure at point C; Figure 7 This is a schematic diagram of the stirring mechanism of the present invention; Figure 8 This is a schematic diagram of a partial cross-sectional structure of the present invention; Figure 9 For the present invention Figure 8 Schematic diagram of the structure at point D.

[0018] In the diagram: 1. Support body; 11. Fixing seat; 12. Slide rail; 13. Buckle; 14. Feed pipe; 2. Fixing frame; 3. Jacket; 4. First cylinder; 41. Sealed bearing; 5. Second cylinder; 51. Sealing cover; 6. Stirring mechanism; 61. First partition cylinder; 62. Second partition cylinder; 63. First pipe; 64. Driving component; 641. Servo motor; 642. Gear; 643. Gear ring; 7. Tilting mechanism; 71. Slide rod; 72. Connecting block; 73. 74. Triangle plate; 75. Roller; 86. Hydraulic rod; 97. Switching mechanism; 88. Support block; 89. Slide groove; 80. Slider; 81. Support rod; 92. Conduit; 93. Plug-in quick connector; 94. Microwave generator; 95. Fourth conduit; 96. Resonant cavity; 97. Waveguide slot antenna; 68. Partition plate; 69. Third conduit; 69. Flow equalization plate; 50. Lug; 51. Air pump; 51. Heater; 51. Second conduit. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example

[0020] Please see Figure 1-9 The present invention provides a technical solution: a coating device for corn seed production, comprising a support body 1, a fixing frame 2 mounted on the support body 1, a sleeve 3 passing through the fixing frame 2, and a first cylinder 4 and a second cylinder 5 respectively mounted at both ends of the sleeve 3, and further comprising: The stirring mechanism 6 is mounted on the first cylinder 4 and connected to the second cylinder 5. The stirring mechanism 6 drives the seeds to rotate around the inner wall of the jacket 3 while continuously tumbling itself. The tilting mechanism 7 is installed on the support body 1 and is used to drive the support body 1 to tilt for subsequent material discharge.

[0021] The stirring mechanism 6 includes a first partition cylinder 61 and a second partition cylinder 62 installed inside the first cylinder 4 and the second cylinder 5. There are multiple first partition cylinders 61 and second partition cylinders 62, which are the same in shape and number. The side away from each other is fan-shaped, and the side away from each other of multiple first partition cylinders 61 or second partition cylinders 62 forms a complete circle. The side close to each other of the first partition cylinders 61 and second partition cylinders 62 are both circular. The first partition cylinders 61 and second partition cylinders 62 are connected by a first pipe 63. The number of first pipes 63 is equal to the number of first partition cylinders 61, and they are spiral-shaped. The stirring mechanism 6 also includes a driving member 64 installed on the support body 1. The driving member 64 is used to drive the first partition cylinder 61 to rotate.

[0022] The driving component 64 includes a servo motor 641 mounted on the bracket body 1. A gear 642 is mounted on the top of the servo motor 641. A gear ring 643 is sleeved on the first partition cylinder 61. The gear 642 and the gear ring 643 mesh with each other.

[0023] A fixed seat 11 is installed on the main body 1 of the support, and a feed pipe 14 is installed on the fixed seat 11. A sealed bearing 41 is sleeved on the side of the first cylinder 4 away from the second cylinder 5, and the inner wall of one end of the feed pipe 14 is sleeved on the sealed bearing 41.

[0024] The tilting mechanism 7 includes a slide rail 12 installed at the bottom of the support body 1. The slide rail 12 is located on the side close to the first partition cylinder 61. A slide rod 71 is slidably arranged inside the slide rail 12. A connecting block 72 is sleeved on the slide rod 71. A triangular plate 73 is arranged directly below the slide rail 12. Rollers 74 are arranged at the bottom of the three corners of the triangular plate 73. A hydraulic rod 75 is installed on the triangular plate 73. The end of the hydraulic rod 75 away from the triangular plate 73 is fixed to the connecting block 72.

[0025] A switching mechanism 8 is installed on the sleeve 3. The switching mechanism 8 is used to seal or open the second cylinder 5. It includes a support block 81 installed on the sleeve 3. The support block 81 has a groove 82. A slider 83 is slidably arranged in the groove 82. A support rod 84 is installed through the slider 83. The support rod 84 is "U" shaped. A sealing cover 51 is installed on the second cylinder 5. The sealing cover 51 has two hanging ears 511 installed opposite each other. The two hanging ears 511 are respectively sleeved on the two ends of the support rod 84.

[0026] A conduit 9 is installed through the sealed cover 51. An air pump 512 and a heater 513 are installed on the sealed cover 51. The exhaust port of the air pump 512 is connected to the conduit 9 through a second pipe 514, which passes through the heater 513. A partition 631 is respectively provided on the first pipe 63 near the first cylinder 4 and the second cylinder 5. A third pipe 632 is provided between the center of the two partitions 631 and the side of the first cylinder 4 and the second cylinder 5 that is far away from each other. A plug-in quick connector 91 is installed on the end of the conduit 9 near the third pipe 632. A flow equalization plate 633 is respectively provided on the first pipe 63 near the first cylinder 4 and the second cylinder 5. The flow equalization plate 633 is located between the two partitions 631.

[0027] A microwave generator 92 is provided at the end of the conduit 9 away from the second partition 62. A fourth pipe 921 is provided at the output port of the microwave generator 92. The fourth pipe 921 passes through the conduit 9, the third pipe 632 near the second cylinder 5, and the flow equalization plate 633 near the second cylinder 5. A resonant cavity 922 is installed on the side of the flow equalization plate 633 near the second cylinder 5 away from the corresponding side partition 631. A waveguide slot antenna 923 is connected to the resonant cavity 922. There are several waveguide slot antennas 923 arranged in a ring array.

[0028] The microwave generator 92 emits at a frequency of 20 kHz.

[0029] In the journal *CivilDirect*, a paper titled "Emerging technology applications for improving seedgermination" published by E.Rifna, K. Ratish Ramanan, and R. Mahendran mentions that ultrasonic, ultraviolet, and non-thermal plasma treatments can significantly improve seed surface modification and germination rates. Through extensive analysis and experimentation, those skilled in the art have found that, since the coating time for single-can (tube) corn seeds is generally 10-15 minutes, the simultaneous application of microwaves at a frequency of 20-25 kHz during this period has a significant positive effect on the subsequent germination rate of corn seeds, with 20 kHz being the optimal frequency.

[0030] The clip 3 is equipped with buckles 13 on both sides near the second partition cylinder 62, and the support leg of the bracket body 1 away from the triangular plate 73 is polygonal in contact with the ground.

[0031] During the coating process of corn seeds, the sealing cap 51 and one end of the second partition cylinder 62 are sealed by the buckle 13 to prevent the seeds or coating liquid from leaking. The polygonal design of the support legs of the support body 1 away from the triangular plate 73 allows the support body 1 to tilt more smoothly when the tilting mechanism 7 is in operation. After tilting, the contact area between the support body 1 and the ground is larger, and the support body 1 is more stable in the tilted state.

[0032] Working principle: The operator seals the second cylinder 5 with the sealing cover 51 using the buckle 13, and then adds the seeds and coating liquid to the feed pipe 14 in a certain proportion. Due to the inclined setting of the feed pipe 14, the seeds and coating liquid will slide down to the position of the first partition 61. Then, after the servo motor 641 is started, the first cylinder 4 is driven to rotate through the meshing of the gear 642 and the gear ring 643. The first cylinder 4 synchronously drives the first partition 61, the first pipe 63, the second partition 62, and the second cylinder 5 to rotate. At this time, the seeds and coating liquid will enter the first pipe 63 through the first partition 61. It should be noted that the operator can drive the support body 1 to tilt as a whole through the tilting mechanism 7 in the first 1-2 minutes of equipment operation to reduce the time when the seeds and coating liquid enter the first pipe 63. As the first cylinder 4 rotates, multiple first pipes 63 drive the seeds and coating liquid inside them to rotate and tumble around the axis of the toothed ring 643, causing the seeds and coating liquid to mix continuously. At the same time, due to the spiral design of the first pipe 63 itself, the seeds will also tumble continuously inside the first pipe 63, further improving the mixing efficiency of the seeds and coating liquid. During the mixing process of the seeds and coating liquid, the seeds will not be subjected to rigid collisions from external forces, and the force of collisions between seeds is also limited, greatly reducing seed damage. During the seed coating process, the air pump 512 and the microwave generator 92 are turned on simultaneously. The microwave generator 92 transmits microwave energy to the resonant cavity 922 through the fourth pipe 921. Then, under the action of the waveguide slot antenna 923, microwaves are continuously applied to the first pipe 63, thereby improving the germination rate of corn seeds. At the same time, when the microwaves come into contact with the first pipe 63, some of the microwave energy is converted into heat, which plays a positive role in the formation of the coated seeds. The airflow generated by the air pump 512 is heated by the heater 513. The hot airflow passes through the conduit 9 and the third pipe 632, and then passes through the flow equalization plate 633 to heat the first pipe 63, assisting in the formation of the coated corn seeds. After the seeds are coated, a collection basket (bucket) is placed below the second cylinder 5. Then, the staff releases the buckle 13 from the connection between the sealing cover 51 and the second cylinder 5, and opens the hydraulic rod 75. As the hydraulic rod 75 extends, it drives the slide rod 71 to slide in the slide rail 12 through the connecting block 72, and raises the support body 1 to one side of the first cylinder 4. At this time, the servo motor 641 is turned on to drive the first pipe 63 to rotate, and the coated corn seeds are discharged from the equipment.

[0033] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0034] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A coating device for corn seed production, comprising a support body (1), a fixing frame (2) mounted on the support body (1), a sleeve (3) being disposed through the fixing frame (2), and a first cylinder (4) and a second cylinder (5) being respectively mounted at both ends of the sleeve (3), characterized in that: Also include: The stirring mechanism (6) is installed on the first cylinder (4) and connected with the second cylinder (5), the stirring mechanism (6) drives the seed to rotate around the inner wall of the jacket (3) while constantly rolling itself; The inclination mechanism (7) is installed on the support body (1), which is used to drive the support body (1) to incline and discharge.

2. The coating device for corn seed production according to claim 1, characterized in that: The stirring mechanism (6) includes a first cylinder (61) and a second cylinder (62) installed in the first cylinder (4) and the second cylinder (5), the first cylinder (61) and the second cylinder (62) are equal in number and shape, the side away from each other is fan-shaped, and the side away from each other of the plurality of first cylinder (61) or second cylinder (62) is a complete circle, the side close to each other of the first cylinder (61) and the second cylinder (62) is circular, and the first cylinder (61) and the second cylinder (62) are connected by the first pipeline (63), the number of the first pipeline (63) is equal to the number of the first cylinder (61), and the first pipeline (63) is spiral, the stirring mechanism (6) further includes a driving element (64) installed on the support body (1), and the driving element (64) is used to drive the first cylinder (61) to rotate.

3. The coating device for corn seed production according to claim 2, characterized in that: The driving element (64) includes a servo motor (641) installed on the support body (1), a gear (642) is installed at the top of the servo motor (641), a gear ring (643) is sleeved on the first cylinder (61), and the gear (642) and the gear ring (643) are engaged with each other.

4. The coating device for corn seed production according to claim 3, characterized in that: The support body (1) is provided with a fixed seat (11), the fixed seat (11) is provided with a feeding pipe (14), the first cylinder (4) is provided with a sealing bearing (41) away from the second cylinder (5), and one end of the feeding pipe (14) is sleeved on the sealing bearing (41).

5. The coating device for corn seed production according to claim 4, characterized in that: The inclination mechanism (7) includes a slide rail (12) installed at the bottom of the support body (1), the slide rail (12) is located on the side close to the first cylinder (61), a slide rod (71) is slidably arranged in the slide rail (12), a connecting block (72) is sleeved on the slide rod (71), a triangular plate (73) is arranged below the slide rail (12), three rollers (74) are arranged at the bottom of the three corners of the triangular plate (73), a hydraulic rod (75) is installed on the triangular plate (73), and one end of the hydraulic rod (75) away from the triangular plate (73) is fixed with the connecting block (72).

6. The coating device for corn seed production according to claim 5, characterized in that: The clamping cover (51) is provided with a conduit (9), the clamping cover (51) is provided with a gas pump (512) and a heater (513), the exhaust port of the gas pump (512) is communicated with the conduit (9) through a second pipeline (514), and the second pipeline (514) passes through the heater (513) in the middle.

7. The coating device for corn seed production according to claim 6, characterized in that: The clamping cover (51) is provided with a conduit (9), the clamping cover (51) is provided with a gas pump (512) and a heater (513), the exhaust port of the gas pump (512) is communicated with the conduit (9) through a second pipeline (514), and the second pipeline (514) passes through the heater (513) in the middle.

8. The coating device for corn seed production according to claim 7, characterized in that: The conduit (9) is provided with a microwave generator (92) away from the second cylinder (62), and the wave outlet of the microwave generator (92) is provided with a fourth pipeline (921); the fourth pipeline (921) penetrates the conduit (9), the third pipeline (632) close to the second cylinder (5) and the flow uniformizing plate (633) close to the second cylinder (5); the flow uniformizing plate (633) close to the second cylinder (5) is provided with a resonant cavity (922) away from the corresponding side baffle (631); the resonant cavity (922) is communicated with a waveguide slot antenna (923); and the waveguide slot antenna (923) is annular array.

9. The coating device for corn seed production according to claim 8, characterized in that: The frequency of the microwave generator (92) is 20 kHz.

10. The coating device for corn seed production according to claim 9, characterized in that: The clamping cover (51) is provided with a conduit (9), the clamping cover (51) is provided with a gas pump (512) and a heater (513), the exhaust port of the gas pump (512) is communicated with the conduit (9) through a second pipeline (514), and the second pipeline (514) passes through the heater (513) in the middle. The clamping cover (51) is provided with a conduit (9), the clamping cover (51) is provided with a gas pump (512) and a heater (513), the exhaust port of the gas pump (512) is communicated with the conduit (9) through a second pipeline (514), and the second pipeline (514) passes through the heater (513) in the middle.

Citation Information

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