A rice and loach co-culturing device

Abstract

The application discloses a kind of rice loach co-worked seed and breed device, including multiple planting blocks of array arrangement, and mud loach nest is formed between planting block and paddy field bottom mud;Planting block is provided with sowing device, and sowing device includes hopper, support, underframe, feeder, direct current air pump, air pipe, branch pipe and discharge pipe;Hopper is used to contain rice seed, including the straight tower structure of upper part and the partial funnel structure of lower part, and feeder is arranged at the outlet of partial funnel structure;Support is connected below straight tower structure, support is connected with underframe, and direct current air pump is arranged in support, and direct current air pump is connected with air pipe, feeder is connected with air pipe by branch pipe, and the end of air pipe is connected with discharge pipe, and the end of discharge pipe is connected with nozzle, and nozzle is used to throw rice seed to the planting nest of planting block and the paddy field near planting block;The survival rate, growth rate and rice yield of seed and breed device seed and breed mud loach are significantly improved, and the quality of mud loach and rice is improved, and economic benefit is significantly increased.

Description

Technical Field

[0001] This invention belongs to the field of crop and aquaculture technology, and specifically relates to a crop and aquaculture device for rice-loach co-cultivation. Background Technology

[0002] Rice-loach farming is a production method that organically combines aquaculture and crop cultivation. Through the symbiotic relationship between rice and loach, it fully utilizes water and land resources to increase both rice and fish yields. This technology not only benefits environmentally friendly development but also effectively promotes economic growth for farmers. Utilizing loach on the rice paddy surface provides not only loach products but also benefits from the loach's ability to consume pests and weeds, excrete manure, and agitate the soil to promote fertilizer decomposition, creating favorable conditions for rice growth. This can generally increase rice yield by about 10%.

[0003] Loach farming in rice paddies began in the mid-1950s, primarily relying on natural harvesting with artificial breeding playing a secondary role. With the development of aquaculture, loach farming has gradually become a specialty aquaculture, encouraging farmers to utilize rice paddies and ponds for loach farming to increase their income. With the continuous development of rice-fish farming technology, loach farming in rice paddies is characterized by low investment and quick returns. Generally, rice paddies with good water retention and slow seepage are selected, and the water depth is maintained at over 20 cm before transplanting. Loach can be harvested and sold after four months of rearing. However, with the development of loach farming, some problems have also emerged. The dense rice seedlings provide ideal activity, hiding, and foraging grounds for wild animals, such as birds, snakes, and rodents, all natural predators of loach. Furthermore, the shallow, flat bottom of rice paddies provides poor concealment, and the shallow silt after drying makes it difficult for loach to escape when suddenly attacked, resulting in a low survival rate during rice-fish farming. Further improvements are needed. Summary of the Invention

[0004] This invention provides a rice-loach co-culture device that can solve the problem of low survival rate of loach in rice paddy farming due to susceptibility to natural enemies. This invention achieves the goal of high survival rate loach farming while increasing rice yield.

[0005] To solve the above problems, the technical solution provided by the present invention is as follows:

[0006] This invention provides a rice-loach co-cultivation device, which includes multiple planting blocks (3) arranged in an array, and each planting block (3) is fixed above the paddy field bottom mud (6) by a fixing rod (7), and a loach nest (5) is formed between the planting block (3) and the paddy field bottom mud (6);

[0007] A seeder is provided on the planting block (6). The seeder includes a hopper (9), a support (10), a base frame (11), a feeder (12), a DC air pump (13), an air pipe (14), a branch pipe (15), and a discharge pipe (16). The hopper (9) is used to hold rice seeds and includes an upper straight hopper structure (9-1) and a lower eccentric funnel structure (9-2). The feeder (12) is provided at the outlet of the eccentric funnel structure (9-2). The support (10) is connected below the straight hopper structure (9-1). (10) is connected to a base frame (11), and a DC air pump (13) is installed inside the support frame (10). The DC air pump (13) is connected to the air pipe (14). The feeder (12) is connected to the air pipe (14) through the branch pipe (15). The end of the air pipe (14) is connected to the discharge pipe (16). The end of the discharge pipe (16) is connected to the nozzle (17). The nozzle (17) is used to sprinkle rice seeds into the planting hole (3-1) of the planting block (3) and the nearby paddy field (1) of the planting block (3).

[0008] When part of the rice plant's roots are embedded in the paddy field mud (6), and part of the roots form a root cluster around the rice plant between the planting block (3) and the paddy field mud (6), a loach nest (5) with rich dissolved oxygen is formed between the root clusters below the planting board (3), which is suitable for loach to inhabit and hide.

[0009] In an optional embodiment of the present invention, the planting block (3) is a rectangular structure with a width of 50-60 cm and an area of ​​0.5-3 square meters. The distance between two adjacent planting blocks (3) is 1-2 meters.

[0010] In an optional embodiment of the present invention, the feeder (12) includes a strip (12-1), a wind plate (12-2), a shaft (12-3), and a collar (12-4). The strip (12-1) is a long strip structure. The shaft (12-3) is fixed on the long side of the strip (12-1). The collar (12-4) is provided at both ends of the shaft (12-3). The strip (12-1) can rotate around the shaft (12-3). When the strip (12-1) is open, rice seeds can fall. When not in operation, the strip (12-1) has a sealing function to prevent rice seeds from falling.

[0011] The wind vane (12-2) is fixed on the shaft (12-3). The wind vane (12-2) is perpendicular to the plane of the strip (12-1). A branch pipe opening (15-2) is connected to the center of the wind vane (12-1). High-pressure gas flows out of the branch pipe (15) and blows the wind vane. The wind vane (12-2) drives the shaft (12-3) to rotate, which in turn drives the strip (12-1) to open the slot, allowing the rice seeds to fall.

[0012] In an optional embodiment of the present invention, an impeller (15-3) is provided at the opening (15-2) of the branch pipe. The gas drives the impeller (15-3) to rotate. The rotating impeller (15-3) cuts the high-pressure gas and generates a pulse force on the air plate (12-2), which is conducive to the falling of rice seeds. The DC air pump (13) is used to provide air power, which blows the air plate (12-2) to rotate through the branch pipe (15) to make the rice seeds fall. The falling rice seeds fall into the air pipe (14) and are blown into the discharge pipe (16) by the air pipe (14) and are sprayed out evenly.

[0013] In an optional embodiment of the present invention, the discharge pipe (16) includes a rigid pipe (16-1), a flexible pipe (16-2), and a diverging section (16-3). The flexible pipe (16-2) connects two spaced portions of the rigid pipe (16-1). The diverging section (16-3) is located at the end of the rigid pipe (16-1). The diverging section (16-3) has a fan-shaped structure with radial strips inside to promote uniform dispersion of rice grains. The flexible pipe (16-2) is manually controlled in direction during operation.

[0014] In an optional embodiment of the present invention, a valve (15-1) is provided on the branch pipe (15), and the valve (15-1) is used to adjust its size until a suitable rice seed falling speed is achieved.

[0015] Beneficial Effects: This invention provides a rice-loach co-cultivation device, comprising multiple planting blocks arranged in an array, with loach nests formed between the planting blocks and the paddy field bottom mud; a seeder is installed on the planting blocks, the seeder including a hopper, a support, a base frame, a feeder, a DC air pump, an air pipe, a branch pipe, and a discharge pipe; the hopper is used to hold rice seeds, including an upper straight hopper structure and a lower eccentric funnel structure, with a feeder installed at the outlet of the eccentric funnel structure; a support is connected below the straight hopper structure, the support is connected to the base frame, a DC air pump is installed inside the support, the DC air pump is connected to an air pipe, the feeder is connected to the air pipe through a branch pipe, the end of the air pipe is connected to the discharge pipe, and the end of the discharge pipe is connected to a nozzle, the nozzle is used to scatter rice seeds into the planting nests of the planting blocks and into the nearby paddy field; the survival rate, growth rate, and rice yield of the loach raised by this device are significantly improved, the quality of the loach and rice is enhanced, and the economic benefits are significantly increased. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments or prior art, the drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a top view of a rice-loach co-culture device provided in an embodiment of this application.

[0018] Figure 2 This is a schematic diagram of the planting block structure of a rice-loach co-culture device provided in an embodiment of this application.

[0019] Figure 3 and Figure 4 This is a schematic diagram of the planting block and loach nest of a rice-loach co-culture device provided in an embodiment of this application.

[0020] Figure 5 This is a schematic diagram of the seeder structure of a rice-loach co-culture device provided in an embodiment of this application.

[0021] Figure 6 This is a schematic diagram of the hopper structure of a rice-loach co-culture device provided in an embodiment of this application.

[0022] Figure 7 and Figure 8 This is a schematic diagram of the seeder portion of a rice-loach co-culture device provided in an embodiment of this application. Detailed Implementation

[0023] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0024] like Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, this embodiment of the invention provides a rice-loach co-cultivation device, comprising multiple planting blocks 3 arranged in an array, each planting block 3 being fixed above the paddy field bottom mud 6 by a fixing rod 7, with loach nests 5 formed between the planting block 3 and the paddy field bottom mud 6. An organic pile 4 is set between two adjacent planting blocks 3, the organic pile 4 having a conical structure. The fixing rod 7 is fixed in the fixing holes 8 of two adjacent planting blocks 3 in the paddy field 1. The planting block 3 is preferably rectangular, with a width of 50-60 cm and an area of ​​0.5-3 square meters, and the distance between two adjacent planting blocks 3 is 1-2 meters.

[0025] This embodiment of rice-loach co-culture includes rice planting, loach nest construction, organic pile setup, loach fry stocking, and rice-loach harvesting. After the paddy field 1 is leveled, dikes 2 are set up around the paddy field 1. Multiple planting blocks 3 are arranged in an array within the dikes 2. The planting blocks 3 serve as floating materials for planting rice. The area of ​​the planting blocks is determined according to the number of loaches stocked, with approximately 1-2 square meters of planting blocks for every 200 loaches. Too narrow a block is not conducive to hiding, too wide a block can lead to oxygen deficiency in the middle, and too large a distance between the planting blocks is not suitable for the loaches to hide in case of emergencies. Planting blocks 3 have planting holes 3-1 for planting rice plants. Planting blocks 3 have holes for connecting to fixing rods 7, ensuring that the planting blocks 3 cannot move horizontally but can only move up and down with the water level. After the planting blocks 3 are set up, rice seeds are scattered in the paddy field 1, with a slightly larger amount scattered near the planting blocks 3 for later transplanting onto them.

[0026] like Figure 5 and Figure 6 As shown, a seeder is installed on planting block 6. The seeder includes a hopper 9, a support 10, a base frame 11, a feeder 12, a DC air pump 13, an air pipe 14, a branch pipe 15, and a discharge pipe 16. The hopper 9 is used to hold rice seeds and includes an upper straight hopper structure 9-1 and a lower eccentric funnel structure 9-2. The feeder 12 is installed at the outlet of the eccentric funnel structure 9-2. The support 10 is connected to the lower part of the straight hopper structure 9-1, and the base frame 11 is connected to the support 10. The DC air pump 13 is installed inside the support 10 and is connected to the air pipe 14. The feeder 12 is connected to the air pipe 14 through the branch pipe 15. The end of the air pipe 14 is connected to the discharge pipe 16, and the end of the discharge pipe 16 is connected to a nozzle 17. The nozzle 17 is used to scatter rice seeds into the planting holes 3-1 of planting block 3 and into the nearby paddy field 1.

[0027] When part of the rice plant's roots are embedded in the paddy field mud 6, and another part of the roots form a root cluster around the rice plant between the planting block 3 and the paddy field mud 6, a loach nest 5 with rich dissolved oxygen is formed between the root clusters below the planting board 3, which is suitable for loach to inhabit and hide.

[0028] The discharge pipe 16 includes a rigid pipe 16-1, a flexible pipe 16-2, and a dispersing section 16-3. The flexible pipe 16-2 connects the two spaced sections of the rigid pipe 16-1. The dispersing section 16-3 is located at the end of the rigid pipe 16-1 and has a fan-shaped structure with radial strips inside to promote even dispersal of the rice grains. The flexible pipe 16-2 is manually controlled in direction during operation.

[0029] like Figure 7 and Figure 8As shown, the feeder 12 includes a strip 12-1, a wind plate 12-2, a shaft 12-3, and a collar 12-4. The strip 12-1 is a long strip structure. The shaft 12-3 is fixed on the long side of the strip 12-1. The shaft 12-3 is provided with collars 12-4 at both ends. The strip 12-1 can rotate around the shaft 12-3. When the strip 12-1 is open, the rice seeds can fall. When not in operation, the strip 12-1 acts as a seal to prevent the rice seeds from falling.

[0030] The air deflector 12-2 is fixed on the shaft 12-3. The air deflector 12-2 is perpendicular to the plane of the strip plate 12-1. A branch pipe opening 15-2 is connected to the center of the air deflector 12-1, and the branch pipe opening 15-2 is the end of the branch pipe 15. High-pressure gas flows out of the branch pipe 15 and blows the air deflector. The air deflector 12-2 drives the shaft 12-3 to rotate, which in turn drives the strip plate 12-1 to open the slot, allowing the rice seeds to fall.

[0031] An impeller blade 15-3 is located at the branch pipe opening 15-2. The gas drives the impeller blade 15-3 to rotate, and the rotating impeller blade 15-3 cuts the high-pressure gas, generating a pulse force on the air vane 12-2, which facilitates the falling of rice seeds. The DC air pump 13 provides air power, which blows the air vane 12-2 through the branch pipe 15 to make the rice seeds fall. The falling rice seeds fall into the air pipe 14 and are then blown into the discharge pipe 16 by the air pipe 14, where they are sprayed out evenly.

[0032] like Figure 7 As shown, a valve 15-1 is installed on the branch pipe 15. The valve 15-1 is used to adjust its size until the appropriate falling speed of the rice seeds is achieved.

[0033] After planting block 3, loach fry can be released at a rate of approximately 20,000 fry per acre (5 cm in length). One week later, they can be fed appropriate amounts of soybean cake, earthworms, soybean residue, and bran, ideally within 3 hours. If no feeding is provided, the stocking density should be controlled at around 8,000 to 10,000 fry. The rearing cycle is approximately 3-4 months. Harvesting takes place after rice harvest. If the loaches do not reach market size by rice harvest time, the water level should be increased to approximately 20 cm after harvest to continue rearing. When catching loaches, drain the paddy field; the loaches will gather in their nests under the planting blocks. At this point, uncover the planting blocks and use a scoop to catch the loaches. Rice is harvested manually or mechanically. When harvesting mechanically, the harvester tracks should not run over the planting blocks. Therefore, when setting up the planting blocks, they should be far away from the field ridges to facilitate the harvester turning around. The row spacing of the planting blocks should also meet the operating conditions of the harvester tracks on both sides not running over the planting blocks.

[0034] Example 1

[0035] There are four paddy fields, each 2 mu (approximately 0.33 hectares) in size, with good water and transportation conditions, suitable for rice-loach farming. The rice and loach are farmed according to the technical solution of a rice-loach co-cultivation device of this invention.

[0036] Rice cultivation includes planting blocks and seed sowing. After the paddy field is leveled, planting blocks are set up. These blocks serve as floating materials for planting rice. The area of ​​the planting blocks is determined based on the stocking density of loaches, with approximately 1 square meter of planting block for every 200 loaches. The planting blocks are rectangular, with a width of about 50 centimeters, and the distance between each block is set at 1.5 meters to ensure that the harvester's tracks do not run over them during harvesting. The planting blocks are kept at least 4 meters away from the paddy field ridges to prevent the harvester from running over them when turning around. Planting holes are provided on the planting blocks for planting rice seedlings. The blocks have holes and are secured with fixing rods to ensure they can only move up and down with the water level, not horizontally. After the planting blocks are set up, rice seeds are sown in the paddy field, with a slightly larger amount sown near the planting blocks for later transplanting. Seeders are used for sowing the rice seeds.

[0037] Creating loach nests: After the rice seeds are sprayed, transplant the seedlings to planting block 3 when they grow to more than 15 cm. Keep the water depth in paddy field 1 at about 5 cm and apply fertilizer to promote the root growth of the seedlings. As the seedlings grow, gradually increase the water level to about 10 cm. Some of the rice plant roots will take root in the paddy field, while others will form root clusters around the rice plant between planting block 3 and the bottom mud 6 of the paddy field. Under the planting block 3, among the root clusters, a space rich in dissolved oxygen suitable for loaches to inhabit and hide is formed, which is the loach nest 5.

[0038] Organic Pile 4: This consists of small piles of organic matter evenly distributed within Paddy Field 1, approximately 25 cm in diameter and 10 cm high. Organic Pile 4 serves two purposes: providing organic fertilizer for the rice and directly and indirectly providing food for the loaches. It is set up when the rice seedlings reach about 10 cm in height. The organic piles are made from fermented chicken manure or fermented livestock manure. The organic piles promote the reproduction and growth of aquatic animals, providing food for the loaches. 300 catties of organic material is piled for every 10,000 loach fry, and no more than 600 catties per mu (approximately 0.067 hectares) of paddy field.

[0039] Loach fry stocking and rice-loach harvesting: Loach fry can be stocked immediately after planting blocks 3, at a rate of 20,000 fry per mu (5 cm in length). After one week, they can be fed appropriate amounts of soybean cake, earthworms, soybean residue, and bran, with the goal of feeding them within 3 hours. The breeding cycle is about 3 months. Harvesting takes place after the rice harvest. If the loaches do not reach market size at the time of rice harvest, the water level should be increased to about 20 cm after harvesting, and they should continue to be raised for another 20 days. When catching loaches, drain the paddy field. The loaches will gather in the loach nests under the planting blocks. At this time, uncover the planting blocks and use a scoop to catch the loaches.

[0040] The survival rate of the four paddy fields was over 95%, with an average yield of 385 jin of marketable loach per mu (average weight of over 10 grams per individual). The rice yield increased by an average of 5% compared to the same period in history. Taking loach as an example, the marketable loach was priced at 8 yuan per jin, and the output value of each paddy field increased by more than 3,000 yuan, resulting in significant ecological and economic benefits.

[0041] Example 2

[0042] There are three existing paddy fields, each with an area of ​​4 mu (approximately 0.67 hectares) and good water and transportation conditions, suitable for rice-loach farming. The rice and loach are farmed according to the technical solution of a rice-loach co-cultivation device of the present invention.

[0043] Rice cultivation includes planting blocks and seed distribution. After the paddy field is leveled, planting blocks are set up. These blocks serve as floating materials for planting rice. The area of ​​the planting blocks is determined based on the stocking density of loaches, with approximately 1 square meter of planting block allocated for every 200 loaches. The planting blocks are rectangular, with a width of about 60 centimeters. The distance between each planting block is set at 1.5 meters to ensure that the harvester's tracks do not run over the blocks during harvesting. The planting blocks are kept at least 5 meters away from the field ridges to prevent the harvester from running over them when turning around. Planting holes are provided on the planting blocks for planting rice seedlings. The planting blocks have holes and are secured with fixing rods to ensure that they can only move up and down with the water level, not horizontally. After the planting blocks are set up, rice seeds are distributed in the paddy field, with a slightly larger amount distributed near the planting blocks for later transplanting. Seeders are used for distributing the rice seeds.

[0044] Creating loach nests: After the rice seeds are sprayed, transplant the seedlings to the planting blocks when they reach 15 cm in height. Maintain a water depth of about 5 cm in the paddy field and apply fertilizer to promote root growth. As the seedlings grow, gradually increase the water level to about 10 cm. Some of the rice plant roots will be embedded in the paddy field, while others will form root clusters around the plant between the planting block and the field bottom. Under the planting block, these root clusters will create an oxygen-rich space suitable for loaches to inhabit and hide, which is called a loach nest.

[0045] Organic composting: These are small mounds of organic matter evenly distributed throughout the paddy field, approximately 25 cm in diameter and 10 cm high. The organic compost provides organic fertilizer for the rice and directly and indirectly provides food for the loaches. It is set up when the rice seedlings reach about 10 cm in height. The organic compost uses fermented livestock manure. The organic compost promotes the reproduction and growth of aquatic animals, providing food for the loaches. Approximately 300 catties of compost is used per 10,000 loach fry.

[0046] Loach fry stocking and rice-loach harvesting: Loach fry can be stocked immediately after planting block 3, at a rate of 10,000 fry / mu (4 cm in length). The stocking cycle is 4 months, during which the loaches are not fed. Harvesting takes place after rice harvesting, when the loaches reach marketable size. Harvesting begins immediately after the rice harvest. The loaches gather in their nests under the planting blocks. At this time, the planting blocks are uncovered, and the loaches are caught using a scoop.

[0047] The survival rate of the three paddy fields was over 90%, with an average yield of 198 jin of marketable loach per mu (average weight of over 10 grams per individual). The rice yield increased by an average of 5% compared to the same period in history. Taking loach as an example, the marketable loach was priced at 8 yuan per jin, and the output value of each paddy field increased by more than 1,580 yuan, resulting in significant ecological and economic benefits.

[0048] In summary, although the present invention has been disclosed above with reference to preferred embodiments, the above preferred embodiments are not intended to limit the present invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the scope defined in the claims.

Claims

1. A rice-loach co-culture device, characterized in that, It includes multiple planting blocks arranged in an array, and each planting block is fixed above the paddy field bottom mud by a fixing rod, and a loach nest is formed between the planting block and the paddy field bottom mud; A seeder is installed on the planting block. The seeder includes a hopper, a support frame, a base frame, a feeder, a DC air pump, an air pipe, a branch pipe, and a discharge pipe. The hopper is used to hold rice seeds and includes an upper straight hopper structure and a lower eccentric funnel structure. A feeder is installed at the outlet of the eccentric funnel structure. The support frame is connected to the bottom of the straight hopper structure. The support frame is connected to the base frame. A DC air pump is installed inside the support frame. The DC air pump is connected to the air pipe. The feeder is connected to the air pipe through the branch pipe. The end of the air pipe is connected to the discharge pipe. The end of the discharge pipe is connected to a nozzle. The nozzle is used to scatter rice seeds into the planting holes of the planting block and into the nearby paddy field. When part of the rice plant's roots are embedded in the mud at the bottom of the paddy field, and another part of the roots form a root cluster around the rice plant between the planting block and the mud at the bottom of the paddy field, a loach nest with rich dissolved oxygen is formed between the root clusters below the planting block, which is suitable for loach to inhabit and hide. The feeder includes a strip plate, a wind plate, a shaft, and a collar. The strip plate is a long strip structure. The shaft is fixed on the long side of the strip plate. The collars are provided at both ends of the shaft. The strip plate can rotate around the shaft. When the strip plate is open, the rice seeds can fall. When not in operation, the strip plate acts as a seal to prevent the rice seeds from falling. The air deflector is fixed on the shaft and is perpendicular to the plane of the strip plate. A branch pipe opening is connected to the center of the air deflector. High-pressure gas flows out of the branch pipe and blows the air deflector. The air deflector drives the shaft to rotate, which in turn drives the strip plate to open the slot, allowing the rice seeds to fall. The branch pipe opening has an impeller blade. The gas drives the impeller blade to rotate. The rotating impeller blade cuts the high-pressure gas and generates a pulse force on the air plate, which helps the rice seeds fall. The DC air pump is used to provide air power, which blows the air plate to rotate through the branch pipe, causing the rice seeds to fall. The falling rice seeds fall into the air pipe and are then blown into the discharge pipe by the air pipe, where they are sprayed out evenly.

2. The rice-loach co-culture device according to claim 1, characterized in that, The planting block is rectangular in shape, with a width of 50-60 cm and an area of ​​0.5-3 square meters. The distance between two adjacent planting blocks is 1-2 meters.

3. The rice-loach co-culture device according to claim 1, characterized in that, The discharge pipe includes a rigid pipe, a flexible pipe, and a dispersing section. The flexible pipe connects two spaced sections of the rigid pipe. The dispersing section is located at the end of the rigid pipe and has a fan-shaped structure with radial strips inside to promote the uniform dispersing of rice grains. The hose is manually oriented during operation.

4. The rice-loach co-culture device according to claim 1, characterized in that, The branch pipe is equipped with a valve, which is used to adjust its size until a suitable falling speed for the rice seeds is achieved.

Images