Multistage soybean seed screening device
Patent Information
- Application Number
- CN202522355345.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-06
- Publication Date
- 2026-09-29
- Estimated Expiration
- 2035-11-06
AI Technical Summary
[0003]本实用新型针对现有技术中存在的技术问题，提供大豆种子多级过筛处理装置来解决现有装置拨料机构采用单一固定行程设计，导致种子堆积、筛孔利用率低、筛选精度与效率双低，筛选模式单一，适配不同粒度或纯度要求的种子需更换筛网或拨料部件，操作繁琐且设备维护成本高的问题
1、本装置通过电机、第二同步带、传动轮、齿条、往复架、弹簧的多部件联动设计，改变了现有装置拨料行程固定的缺陷，电机启动后，其输出轴通过第二同步带同步驱动传动轮转动，而传动轮上交替设置的三个不同传动行程的有齿段，可依次与往复架上的齿条啮合，当有齿段与齿条啮合时，推动往复架沿筛箱滑动并带动集料箱及拨料板移动，且三个有齿段能分别赋予拨料板小幅度高频次、中幅度中频次、大幅度低频次的交替运动轨迹，当有齿段脱离齿条时，往复架侧面阵列的弹簧可快速将其复位，确保运动连续性，这种多行程交替拨料模式，能实现筛带表面种子的无死角翻动，避免现有装置中种子局部堆积导致的部分筛孔闲置、部分筛孔过载堵塞问题，使筛孔利用率较传统单一行程设计提升，同时，动态变化的拨料轨迹可让种子更均匀地接触筛孔，筛选精度提升，且上述结构设置无需额外增加电机功率即可实现效率翻倍，形成动力传递、多行程拨料、弹性复位的高效协同闭环。
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Figure CN224807780U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of screening device technology, specifically a multi-stage screening device for soybean seeds. Background Technology
[0002] Soybean seed screening is a crucial link in the agricultural production chain, ensuring seed quality and improving subsequent sowing germination rates and crop yields. In actual production, screening devices need to achieve two core functions: first, to accurately grade soybean seeds of different sizes to meet different sowing scenarios; and second, to efficiently remove impurities such as broken grains and sand from the seeds to ensure seed purity. Currently, most mainstream soybean seed screening devices on the market are based on the traditional structural design of a fixed screen and a single feeding mechanism. They use a motor to drive the screen to vibrate or the feeding mechanism to reciprocate, allowing the seeds to pass through the screen holes by gravity for grading. However, existing devices have many technical shortcomings in practical applications, as detailed below: The existing feeding mechanism adopts a single fixed stroke design, which leads to seed accumulation, low screen hole utilization, low screening accuracy and efficiency, and a single screening mode. To adapt to seeds with different particle size or purity requirements, the screen or feeding component needs to be replaced, which is cumbersome to operate and has high equipment maintenance costs. Based on this, the present invention provides a multi-stage sieving device for soybean seeds to solve the problems mentioned in the background art. Utility Model Content
[0003] This utility model addresses the technical problems existing in the prior art by providing a multi-stage sieving device for soybean seeds. This solves the problems of existing devices using a single fixed stroke design for the feeding mechanism, which leads to seed accumulation, low utilization rate of the sieve holes, low screening accuracy and efficiency, a single screening mode, and the need to replace the sieve or feeding component to adapt to seeds with different particle size or purity requirements, resulting in cumbersome operation and high equipment maintenance costs.
[0004] The technical solution of this utility model to solve the above-mentioned technical problems is as follows: a multi-stage sieving treatment device for soybean seeds, including a sieve box and a first synchronous belt, a motor is installed on the sieve box and a reciprocating frame is slidably connected thereto, a second synchronous belt is driven to the output shaft of the motor, a transmission wheel is rotatably installed on the sieve box, and three toothed sections and three toothless sections are alternately arranged on the transmission wheel, a rack is installed on the reciprocating frame, the three toothed sections mesh with the rack in sequence, and the transmission stroke of the three toothed sections to the rack is different, springs are arrayed on the side of the reciprocating frame, and the other end of the springs is fixedly connected to the sieve box, and three screening mechanisms are arrayed in the vertical direction inside the sieve box; The screening mechanism includes a collection box and two belt rollers rotatably connected to the screen box. The collection box is fixedly connected to the reciprocating frame. Material feeding plates are arranged in an array on the collection box. Both belt rollers are connected to the first synchronous belt drive. Each belt roller is equipped with a rotation knob. A screen belt is wound between the two belt rollers. Four screening zones are arranged in sequence along the vertical direction of the belt rollers. Each screening zone is arranged with screen holes arranged in an array. The screen hole diameters in each screening zone are different. It also includes two straight shafts rotatably connected to the screen box and a tension adjustment mechanism for adjusting the tension of the first synchronous belt. The transmission wheel and the two straight shafts are all connected to the second synchronous belt. Each of the two straight shafts is equipped with a swing gear, and one of the belt rollers is equipped with a driven gear. The two swing gears alternately mesh with the driven gear.
[0005] Based on the above technical solution, the present invention can be further improved as follows.
[0006] As a preferred technical solution of this utility model, it also includes a bracket, which is fixedly connected to the screen box. A central control unit is installed on the end face of the screen box, and a fine material discharge nozzle is installed at the bottom of the screen box.
[0007] As a preferred technical solution of this utility model, the collecting box is disposed above the screen belt, and the bottom surfaces of both the collecting box and the feeding plate are provided with rubber bristles, which are in contact with the screen belt.
[0008] As a preferred technical solution of this utility model, the screening mechanism further includes two guide rollers rotatably connected to the screen box, both guide rollers being connected to the screen belt drive, the two guide rollers being respectively arranged on both sides of the collection box, and a coarse material discharge nozzle being installed at the tail of the screen box.
[0009] As a preferred technical solution of this utility model, the tension adjustment mechanism includes a tension block slidably connected to the screen box, a tension push rod installed on the bottom surface of the tension block, the tension push rod being fixedly connected to the screen box, a tension wheel being rotatably installed on the tension block, the tension wheel being drivenly connected to the first synchronous belt, and a pulley connected to the first synchronous belt being fixedly installed on the belt roller.
[0010] As a preferred technical solution of this utility model, the center angles corresponding to the effective meshing tooth segments on the two swinging missing gears are both 90°, the effective meshing tooth segments on the two swinging missing gears are offset at 90° on the screen box, and the two swinging missing gears are respectively set on both sides of the driven gear.
[0011] As a preferred embodiment of this invention, the angle between the axis of the belt roller and the horizontal plane is 20°.
[0012] The beneficial effects of this utility model are: 1. This device overcomes the limitation of fixed material feeding stroke in existing devices by employing a multi-component linkage design involving a motor, a second synchronous belt, a transmission wheel, a rack, a reciprocating frame, and springs. After the motor starts, its output shaft synchronously drives the transmission wheel to rotate via the second synchronous belt. Three toothed segments with alternating transmission strokes on the transmission wheel sequentially mesh with the rack on the reciprocating frame. When a toothed segment meshes with the rack, it pushes the reciprocating frame to slide along the screen box, thereby moving the collection box and the feeding plate. Furthermore, the three toothed segments can respectively impart alternating motion trajectories to the feeding plate: small amplitude high frequency, medium amplitude medium frequency, and large amplitude low frequency. When the toothed segment disengages from the rack, the springs arrayed on the side of the reciprocating frame can quickly reset it, ensuring continuous motion. This multi-stroke alternating feeding mode can achieve seamless turning of seeds on the screen surface, avoiding the problems of some screen holes being idle and others being overloaded and blocked due to local seed accumulation in existing devices. This improves the utilization rate of screen holes compared to the traditional single-stroke design. At the same time, the dynamically changing feeding trajectory allows seeds to contact the screen holes more evenly, improving screening accuracy. Moreover, the above structural setup can double the efficiency without adding extra motor power, forming a highly efficient and coordinated closed loop of power transmission, multi-stroke feeding, and elastic reset.
[0013] 2. This device, through the coordinated design of multiple screening zones on the screen belt, belt rollers, indexing knob, tension adjustment mechanism, and three-stage screening mechanism, constructs a flexible screening system that requires no disassembly or replacement of parts. The screen belt has multiple screening zones with different apertures along the vertical direction of the belt rollers. The currently operating screening zone can be switched by rotating the indexing knob on the belt rollers. Combined with the three vertically arrayed screening mechanisms inside the screen box, two core modes can be easily achieved: one is a multi-stage grading mode, in which the apertures of the three screening zones along the vertical direction are set to decrease sequentially, allowing the seeds to undergo coarse screening to remove large impurities and medium screening for grading. First, it features a gradient treatment to remove small particles through fine screening, meeting the differentiated needs of seed particle size in different sowing scenarios. Second, it offers a multi-stage screening mode, where the pore size of the screening zones in the three screening mechanisms is set to be consistent, and the seeds undergo three repeated screenings, improving the impurity removal rate and adapting to the demand for high-purity seeds. In addition, the tension adjustment mechanism can temporarily loosen the first synchronous belt by sliding the tension block through the tension push rod when switching screening zones, so as to facilitate the rotation of the belt roller. After the switching is completed, the tension is reset to ensure stable belt transmission. This design eliminates the cumbersome operation of stopping the machine and disassembling parts required by existing devices to change screens. Attached Figure Description
[0014] Figure 1 This is a schematic diagram of a multi-stage sieving device for soybean seeds. Figure 2 for Figure 1 A magnified schematic diagram of the local structure at point A; Figure 3 for Figure 2 A magnified view of the structure at point B in the middle; Figure 4 A schematic diagram of the material feeding plate and the indexing knob; Figure 5 This is a cross-sectional structural diagram of the material collection box and the material feeding plate; Figure 6 This is a schematic diagram of the structure of the screening belt and screening zone; Figure 7 This is a structural diagram of the reciprocating frame and the collection box.
[0015] The attached diagram lists the components represented by each number as follows: 1. Screen box; 2. First synchronous belt; 3. Motor; 4. Reciprocating frame; 5. Second synchronous belt; 6. Drive wheel; 7. Toothed section; 8. Rack; 9. Spring; 10. Collection box; 11. Belt roller; 12. Feeding plate; 13. Indexing knob; 14. Screen belt; 15. Screening zone; 16. Straight shaft; 17. Oscillating gear; 18. Driven gear; 19. Support; 20. Central control unit; 21. Fine material discharge nozzle; 22. Guide roller; 23. Coarse material discharge nozzle; 24. Tensioning block; 25. Tensioning push rod; 26. Tensioning wheel. Detailed Implementation
[0016] The principles and features of this utility model are described below with reference to the accompanying drawings. The examples given are only for explaining this utility model and are not intended to limit the scope of this utility model.
[0017] The present invention provides the following preferred embodiments. like Figure 1-7 As shown, the soybean seed multi-stage sieving device includes a sieve box 1 and a first synchronous belt 2. It also includes a bracket 19, which is fixedly connected to the screen box 1. A central control unit 20 is installed on the end face of the screen box 1, and a fine material discharge nozzle 21 is installed at the bottom of the screen box 1. The support bracket 19 can provide stable support for the screen box 1; The central control unit 20 can centrally regulate the speed of motor 3, the extension and retraction of tension push rod 25, the switching of screening modes and other key operations, replacing manual adjustment. This not only reduces the difficulty of operation, but also ensures the synchronization and accuracy of the operation of each component through preset parameters, thereby improving screening efficiency. Fine material discharge nozzle 21 collects the final screening of fine soybean seeds or fine impurities; A motor 3 is installed on the screen box 1 and a reciprocating frame 4 is slidably connected to it. A second synchronous belt 5 is driven to the output shaft of the motor 3. A transmission wheel 6 is rotatably installed on the screen box 1. Three toothed sections 7 and three missing tooth sections are alternately arranged on the transmission wheel 6. A rack 8 is installed on the reciprocating frame 4. The three toothed sections 7 mesh with the rack 8 in sequence, and the transmission stroke of the three toothed sections 7 to the rack 8 is different. Springs 9 are arranged in an array on the side of the reciprocating frame 4. The other end of the springs 9 is fixedly connected to the screen box 1. When the motor 3 drives the transmission wheel 6 to rotate via the second synchronous belt 5, the three toothed segments 7 with different transmission strokes on the transmission wheel 6 can alternately mesh with the rack 8, so that the reciprocating frame 4 produces a multi-stroke alternating reciprocating motion state. The spring 9 on the side of the reciprocating frame 4 can quickly reset the reciprocating frame 4 when the toothed section 7 disengages from the rack 8; In a preferred embodiment, the central angles corresponding to the three toothed segments 7 are 30°, 40° and 50° respectively, and the central angles corresponding to the three missing tooth segments are all 80°. Conventional screening devices often use a single, fixed-stroke reciprocating mechanism, which can easily lead to localized accumulation of soybean seeds on the screen belt 14, resulting in some screen holes being idle and others being blocked due to overload.
[0018] In this device, the multi-stroke alternating reciprocating motion can drive the feeding plate 12 to move the seeds in alternating trajectories of small amplitude high frequency, medium amplitude medium frequency, and large amplitude low frequency, ultimately achieving no dead angle coverage on the surface of the screen belt 14, so that the screen holes can participate in screening at the same time, improving the screen hole utilization rate compared to a single stroke and reducing screening omissions.
[0019] Different batches of soybean seeds have different physical characteristics. Conventional devices require the feeding mechanism to be replaced or the stroke to be adjusted to adapt to them, which is cumbersome and costly. The multi-stroke alternating reciprocating motion of this device can dynamically adapt to cover the screening needs of multiple types of seeds. Three screening mechanisms are arranged in a vertical array inside the sieve box 1; The screening mechanism includes a collection box 10 and two belt rollers 11 rotatably connected to the screen box 1. The collection box 10 is fixedly connected to the reciprocating frame 4. Material feeding plates 12 are arrayed on the collection box 10. Both belt rollers 11 are connected to the first synchronous belt 2 for transmission. A pulley connected to the first synchronous belt 2 is mounted on the belt roller 11; Each of the two belt rollers 11 is equipped with a rotation knob 13, and a screen belt 14 is wound between the two belt rollers 11. Along the vertical direction of the belt rollers 11, four screening zones 15 are arranged in sequence on the screen belt 14. Each screening zone 15 is provided with an array of screen holes. The screen hole diameters on each screening zone 15 are different, and the screen hole diameters on the four screening zones 15 increase in sequence. The collecting box 10 is located above the screen belt 14. The bottom surfaces of both the collecting box 10 and the material feeding plate 12 are provided with rubber bristles, which are in contact with the screen belt 14. The length of the rubber bristles is 5-8mm; During operation, each of the three screening mechanisms selects a screening area 15 with a specified screen aperture on the screen belt 14 and enters the screening station, which corresponds to the position of the collection box 10. In the multi-stage screening mode, the sieve aperture of screening zone 15 in the three screening mechanisms decreases in the vertical downward direction, thereby achieving graded screening. Soybean seeds can be successively graded through coarse sieve, medium sieve and fine sieve to meet the classification requirements of seeds of different particle sizes. Furthermore, in the multi-level screening mode, the difference in sieve aperture between any two screening mechanisms can be customized by selecting the specified screening area 15 to adjust the screening parameters during multi-level screening. In the same-level multiple screening mode, the aperture of screening area 15 in the three screening mechanisms is the same in the vertical downward direction, thereby realizing the same-level repeated screening. In this mode, the seeds can be screened three times, effectively removing impurities and seeds that do not match the particle size, and improving the screening accuracy. In a preferred embodiment, in the multi-level grading mode, the upper screening zone 15 has an aperture of 8mm, the middle layer has an aperture of 6mm, and the lower layer has an aperture of 4mm. In the same-level multiple mode, all three layers are 6mm thick; The rubber bristles on the bottom of the collecting box 10 and the bottom of the feeding plate 12 are attached to the screen belt 14. This can gently turn the seeds during the reciprocating motion, avoid hard contact that could damage the seed germ, and ensure the integrity of the seeds. It can also clean the fine impurities on the surface of the screen holes during the turning process, reduce the probability of screen blockage, and maintain the continuity of screening. It also includes two straight shafts 16 rotatably connected to the screen box 1 and a tension adjustment mechanism for adjusting the tension of the first synchronous belt 2. The transmission wheel 6 and the two straight shafts 16 are all connected to the second synchronous belt 5. Each of the two straight shafts 16 is equipped with a swing gear 17, and a driven gear 18 is installed on a belt roller 11. The two swing gears 17 alternately mesh with the driven gear 18.
[0020] The tension adjustment mechanism includes a tension block 24 slidably connected to the screen box 1, a tension push rod 25 mounted on the bottom surface of the tension block 24, the tension push rod 25 being fixedly connected to the screen box 1, a tension wheel 26 being rotatably mounted on the tension block 24, the tension wheel 26 being drivenly connected to the first synchronous belt 2, and a pulley connected to the first synchronous belt 2 being fixedly mounted on the belt roller 11.
[0021] In normal screening mode, the first synchronous belt 2 is kept taut, and the three screen belts 14 reciprocate within the set stroke. Through the reciprocating motion of the screen belts 14, the screen holes on the screen belts 14 are used and worn evenly, thereby reducing the clogging rate of the screen holes. At the same time, the reciprocating motion of the screen belts 14 is used to move the soybeans on the screen belts 14. At the same time, this movement mode can provide seeds with sufficient time to pass through the sieve holes, and can also prevent seed accumulation by reciprocating tossing. Compared with the continuous rotation of the sieve belt 14, the screening accuracy is significantly improved. When it is necessary to switch the position of the screening area 15 in each screening mechanism, the first synchronous belt 2 is in a relaxed state. The position of the screening area 15 is switched by the synchronous rotation of the two belt rollers 11 in the screening mechanism. After the position of the screening area 15 is switched, the first synchronous belt 2 returns to the tensioned state. The screening mechanism also includes two guide rollers 22 rotatably connected to the screen box 1. Both guide rollers 22 are connected to the screen belt 14 for transmission. The two guide rollers 22 are respectively set on both sides of the collection box 10. A coarse material discharge nozzle 23 is installed at the tail of the screen box 1.
[0022] Two guide rollers 22 are respectively set on both sides of the collection box 10 and connected to the screen belt 14 for transmission. They can support and guide the screen belt 14, prevent the screen belt 14 from running off course, wrinkling or sagging during reciprocating motion, and ensure that the screen belt 14 is always in contact with the collection box 10.
[0023] The center angles corresponding to the effective meshing tooth segments on the two oscillating missing gears 17 are both 90°. The effective meshing tooth segments on the two oscillating missing gears 17 are offset at 90° on the screen box 1. The two oscillating missing gears 17 are respectively located on both sides of the driven gear 18.
[0024] The working principle of this utility model is as follows: When working, the support 19 first forms a stable support for the screen box 1, and the central control unit 20 centrally controls the operation of the motor 3, the tensioning push rod 25 and other components. After the motor 3 starts, it drives the transmission wheel 6 and two straight shafts 16 to rotate through the second synchronous belt 5. The three toothed segments 7 with different transmission strokes on the transmission wheel 6 alternately mesh with the rack 8 of the reciprocating frame 4. Combined with the reset action of the spring 9 on the side of the reciprocating frame 4, the reciprocating frame 4 drives the collection box 10 and the array of material-pulling plates 12 to perform multi-stroke alternating reciprocating motion. The rubber soft bristles on the bottom surface of the collection box 10 and the material-pulling plates 12 are attached to the screen belt 14, which gently turns the seeds to avoid damage to the germ and cleans the screen holes of impurities to reduce clogging. In the three vertically arrayed screening mechanisms inside the sieve box 1, the two belt rollers 11 of each screening mechanism are driven by the first synchronous belt 2. The sieve belt 14 wound between the belt rollers 11 reciprocates with the belt rollers 11 under the support and guidance of the guide roller 22. During normal screening, if it is a multi-level screening mode, the aperture of the screening area 15 of the sieve belt 14 of the three screening mechanisms decreases in the vertical downward direction, realizing the gradient classification of seed coarse screening, medium screening and fine screening. If it is a multiple screening mode of the same level, the aperture of the screening area 15 of the sieve belt 14 of the three screening mechanisms is the same, realizing the repeated screening of seeds to improve the accuracy. Meanwhile, the two effective meshing tooth segments on the straight shaft 16, with center angles of 90° and misaligned by 90°, alternately mesh with the driven gear 18 of the belt roller 11 to assist and coordinate the movement of the belt roller 11. During the screening process, fine particles of seeds or impurities are discharged from the fine material discharge nozzle 21 at the bottom of the screen box 1, and coarse material that has not passed through the screen belt 14 is discharged from the coarse material discharge nozzle 23 at the tail. When it is necessary to switch the screening zone 15, the tensioning push rod 25 controls the tensioning block 24 to loosen the first synchronous belt 2, and the rotation knob 13 of the belt roller 11 is rotated to complete the switching of the screening zone 15. After the switching, the first synchronous belt 2 is re-tensioned and the screening operation is resumed.
[0025] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. A multi-stage sieving device for soybean seeds, comprising a sieve box (1) and a first synchronous belt (2), characterized in that, A motor (3) is installed on the screen box (1) and a reciprocating frame (4) is slidably connected to it. A second synchronous belt (5) is connected to the output shaft of the motor (3). A transmission wheel (6) is rotatably installed on the screen box (1). Three toothed sections (7) and three toothless sections are alternately arranged on the transmission wheel (6). A rack (8) is installed on the reciprocating frame (4). The three toothed sections (7) mesh with the rack (8) in sequence. The transmission stroke of the three toothed sections (7) to the rack (8) is different. Springs (9) are arranged in an array on the side of the reciprocating frame (4). The other end of the springs (9) is fixedly connected to the screen box (1). Three screening mechanisms are arranged in an array in the vertical direction inside the screen box (1). The screening mechanism includes a collection box (10) and two belt rollers (11) rotatably connected to the screen box (1). The collection box (10) is fixedly connected to the reciprocating frame (4). A material-pulling plate (12) is arrayed on the collection box (10). Both belt rollers (11) are connected to the first synchronous belt (2) for transmission. Both belt rollers (11) are equipped with a rotation knob (13). A screen belt (14) is wound between the two belt rollers (11). Along the vertical direction of the belt rollers (11), four screening zones (15) are arranged in sequence on the screen belt (14). Each screening zone (15) is arrayed with screen holes. The screen hole diameters on each screening zone (15) are different. It also includes two straight shafts (16) rotatably connected to the screen box (1) and a tension adjustment mechanism for adjusting the tension of the first synchronous belt (2). The transmission wheel (6) and the two straight shafts (16) are all connected to the second synchronous belt (5). Each of the two straight shafts (16) is equipped with a swing gear (17). One of the belt rollers (11) is equipped with a driven gear (18). The two swing gears (17) alternately mesh with the driven gear (18).
2. The soybean seed multi-stage sieving treatment device according to claim 1, characterized in that, It also includes a bracket (19), which is fixedly connected to the screen box (1). A central control unit (20) is installed on the end face of the screen box (1), and a fine material discharge nozzle (21) is installed at the bottom of the screen box (1).
3. The soybean seed multi-stage sieving treatment device according to claim 1, characterized in that, The collection box (10) is located above the screen belt (14). The bottom surfaces of the collection box (10) and the material feeding plate (12) are provided with rubber bristles, which are in contact with the screen belt (14).
4. The multi-stage sieving device for soybean seeds according to claim 3, characterized in that, The screening mechanism also includes two guide rollers (22) rotatably connected to the screen box (1). Both guide rollers (22) are connected to the screen belt (14) for transmission. The two guide rollers (22) are respectively set on both sides of the collection box (10). The tail of the screen box (1) is equipped with a coarse material discharge nozzle (23).
5. The multi-stage sieving device for soybean seeds according to claim 1, characterized in that, The tension adjustment mechanism includes a tension block (24) slidably connected to the screen box (1), a tension push rod (25) installed on the bottom surface of the tension block (24), the tension push rod (25) being fixedly connected to the screen box (1), a tension wheel (26) being rotatably installed on the tension block (24), the tension wheel (26) being drivenly connected to the first synchronous belt (2), and a pulley connected to the first synchronous belt (2) being fixedly installed on the belt roller (11).
6. The multi-stage sieving device for soybean seeds according to claim 1, characterized in that, The center angles corresponding to the effective meshing tooth segments on the two oscillating missing gears (17) are both 90°. The effective meshing tooth segments on the two oscillating missing gears (17) are offset at 90° on the screen box (1). The two oscillating missing gears (17) are respectively set on both sides of the driven gear (18).
7. The multi-stage sieving device for soybean seeds according to claim 1, characterized in that, The angle between the axis of the belt roller (11) and the horizontal plane is 20°.