Anti-blocking multi-stage rapeseed screening device

Abstract

The utility model relates to agricultural implement technical field especially is a kind of multi-stage rapeseed screening device of anti-blocking, device is set by the swing frame driven by driving assembly on rack, hollow screening seat with first, second screening assembly is movably carried on swing frame, one-way valve is equipped between swing frame and screening seat and is clamped and is arranged blow screen air bag, air bag outlet end and the blow nozzle array at second screening mouth place intercommunication, utilize the relative displacement of screening seat reciprocating swing and the continuous extrusion air bag gas generation between frame, while material is mechanically thrown and screened, synchronously to the second screening assembly of easy to block and jam, inject the pulse backflow airflow from bottom to top, further without external fan, forced to eject jammed debris, give screen efficient dynamic self-cleaning ability, greatly improve the continuity of rapeseed screening and clean-up purity.

Description

Technical Field

[0001] This utility model relates to the field of agricultural machinery technology, and in particular to a multi-stage rapeseed screening device that prevents clogging. Background Technology

[0002] Rapeseed is one of my country's main oil crops. Before processing and pressing rapeseed, it must undergo strict impurity removal. After harvesting, rapeseed is usually mixed with debris, dust, sand, pods, and other impurities. Multi-stage screening devices are needed to separate impurities of different types and sizes from pure rapeseed to ensure the quality and oil yield of subsequent processing. Currently, most processing enterprises use multi-layer mechanical screens to complete the initial cleaning operation.

[0003] Existing multi-stage rapeseed screening devices typically use motor-driven vibration to cause the frame containing the screen to move along a specific trajectory. The material is forced to move and is conveyed forward on the inclined screen surface. Large particles of impurities are intercepted, while smaller particles pass through the screen and fall into the next stage. When dealing with complex rapeseed raw materials, in order to ensure the purity of multi-stage screening and effectively separate debris of similar size, it is necessary to arrange screening screens with smaller apertures inside the equipment.

[0004] However, in actual industrial applications, due to the small size of the screen mesh and the relatively large amount of lightweight debris, these traditional screening devices often suffer from severe screen mesh blockage. Once the screen mesh is blocked, it not only directly leads to a sharp decline in the screening rate of rapeseed and the overall operating efficiency of the equipment, resulting in the loss of qualified raw materials, but also forces on-site operators to frequently stop the machine to manually clean the screen, which seriously hinders the continuous screening process of the production line and greatly increases the daily maintenance cost of the equipment. Utility Model Content

[0005] The main purpose of this invention is to provide a multi-stage rapeseed screening device that prevents clogging, aiming to solve the problem of debris clogging that easily occurs in existing screening devices.

[0006] To achieve the above objectives, this utility model provides a multi-stage rapeseed screening device to prevent clogging, the screening device comprising:

[0007] A screening frame, on which a drive assembly is provided;

[0008] A swaying assembly includes a transmission component, a transmission rod, and a swaying frame. The input end of the transmission component is connected to the output end of the drive component, and the output end of the transmission component is connected to the swaying frame. Both ends of the transmission rod are connected to the screening frame and the swaying frame, respectively. A screening seat is movably disposed on the upper end surface of the swaying frame. The screening seat is hollow inside and forms a screening chamber. A feed inlet is disposed on the upper end surface of the screening seat. The two openings of the screening chamber are a first screening port and a second screening port, respectively.

[0009] A first screening component is disposed at a first screening port;

[0010] The second screening component is disposed at the second screening port;

[0011] A blowing sieve assembly includes a blowing sieve airbag and a nozzle array. The blowing sieve airbag is disposed between a swing frame and a sieve seat. The nozzle array is disposed at a second sieve port. The air inlet of the blowing sieve airbag is provided with a one-way valve, and the air outlet of the blowing sieve airbag is connected to the nozzle array through the one-way valve.

[0012] Optionally, both the first screening component and the second screening component include a plurality of screening plates, which are disposed in the screening chamber, and the screening plates of the first screening component are inclined.

[0013] Optionally, the transmission component includes a transmission wheel set, a transmission cam, and a rocker arm. The transmission wheel set is belt driven by the output end of the drive assembly. The output end of the transmission wheel set is coaxially arranged with the transmission cam. The transmission cam is movably connected to one end of the rocker arm, and the other end of the rocker arm is movably connected to the lower end face of the rocker frame.

[0014] Optionally, the side of the screening seat is hinged to the rocker frame, and a spring assembly is also provided on the side of the screening seat away from the hinge end.

[0015] Optionally, the air inlets of the blowing airbag are arranged opposite each other and are connected by a pipe. The nozzle array includes a nozzle tube, and the nozzle tube is connected to the pipe by a one-way valve.

[0016] Optionally, the nozzle array further includes a plurality of sieve nozzles, which are evenly distributed at intervals on the nozzle tube to reciprocate the airflow at the second sieve opening by the volume change of the sieve airbag.

[0017] Optionally, the second screening component includes an inclined screening channel.

[0018] Optionally, the screening device further includes a third screening component disposed within the screening channel.

[0019] Optionally, the third screening component includes a screening perforated plate, which has a plurality of holes matching the size of rapeseed.

[0020] Optionally, a screening hopper is provided at the end of the screening channel, and the screening hopper is also placed below the screening orifice plate to form a third screening port.

[0021] The beneficial effects that this utility model can achieve are as follows:

[0022] This invention solves the problem of frequent clogging of existing screening devices when processing rapeseed due to small screening holes, and achieves simultaneous mechanical screening and pulse pneumatic anti-clogging screening. It sets a swing assembly driven by a drive component on the frame, and uses a transmission component and transmission rod to drive the swing frame to reciprocate to shake the screening seat on it. The first and second screening components are respectively set at the two ends of the screening seat for grading and screening. A blowing air bag with inlet and outlet one-way valves is sandwiched between the swing frame and the screening seat, and its air outlet is connected to the nozzle array at the second screening port.

[0023] This invention directly converts the relative displacement potential energy generated between the screening seat and the frame during reciprocating oscillation into alternating deformation of the airbag volume, thereby autonomously compressing and generating gas. This same-source driving logic ensures that at the moment the material is mechanically thrown, the nozzle array will definitely perform a bottom-up pulse backflush on the easily clogged second screening component. The high-speed penetrating airflow can not only force out the debris and mud stuck in the fine mesh, but also form a weak air flotation layer above the screen surface to reduce the adhesion of the material. No external high-pressure blower is required, eliminating the tedious manual shutdown and screen cleaning, and greatly improving the continuity and screening purity of rapeseed cleaning operations. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the screening device in an embodiment of the present invention;

[0025] Figure 2 This is a schematic axial view of the screening device in an embodiment of the present invention;

[0026] Figure 3 This is a partial structural schematic diagram of the screening device in an embodiment of this utility model.

[0027] Figure label:

[0028] 1-Screening frame, 2-Swing assembly, 3-First screening assembly, 4-Second screening assembly, 5-Blowing assembly, 6-Feed inlet, 7-Screening plate, 8-Spring assembly, 9-Third screening assembly;

[0029] 11-Driver components;

[0030] 21-Transmission component, 22-Transmission rod, 23-Swing frame, 24-Screening seat, 25-Screening chamber;

[0031] 211-Transmission wheel assembly, 212-Transmission cam, 213-Rocking arm;

[0032] 31 - First screening port;

[0033] 41-Second screening port, 42-Screening channel;

[0034] 51-Sieve airbag, 52-Nose array, 53-One-way valve I, 54-One-way valve II;

[0035] 521 - Mouthpiece tube, 522 - Sieve nozzle;

[0036] 91-Sieve plate, 92-Sieve hopper, 93-Third sieve opening.

[0037] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0038] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0039] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0040] In this utility model, unless otherwise explicitly specified and limited, the terms "connection," "fixing," etc., should be interpreted broadly. For example, "fixing" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0041] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0042] Example:

[0043] Please refer to the attached document as well. Figure 1 To be continued Figure 3 This embodiment provides a multi-stage rapeseed screening device to prevent clogging, the screening device comprising:

[0044] Screening frame 1, on which a drive assembly 11 is provided;

[0045] The swing assembly 2 includes a transmission component 21, a transmission rod 22, and a swing frame 23. The input end of the transmission component 21 is connected to the output end of the drive component 11, and the output end of the transmission component 21 is connected to the swing frame 23. The two ends of the transmission rod 22 are respectively connected to the screening frame 1 and the swing frame 23. A screening seat 24 is movably disposed on the upper end surface of the swing frame 23. The screening seat 24 is hollow inside and forms a screening chamber 25. A feed inlet 6 is disposed on the upper end surface of the screening seat 24. The two ends of the screening chamber 25 have openings of a first screening port 31 and a second screening port 41, respectively.

[0046] The first screening component 3 is disposed at the first screening port 31;

[0047] The second screening component 4 is disposed at the second screening port 41;

[0048] The blowing sieve assembly 5 includes a blowing sieve airbag 51 and a blowing nozzle array 52. ​​The blowing sieve airbag 51 is disposed between the swing frame 23 and the sieve seat 24. The blowing nozzle array 52 is disposed at the second sieve port 41. The air inlet end of the blowing sieve airbag 51 is provided with a one-way valve. The air outlet end of the blowing sieve airbag 51 is connected to the blowing nozzle array 52 through the one-way valve.

[0049] In this embodiment, both the first screening component 3 and the second screening component 4 include a plurality of screening plates 7, which are disposed in the screening chamber 25, and the screening plates 7 of the first screening component 3 are inclined.

[0050] In this embodiment, the transmission component 21 includes a transmission wheel set 211, a transmission cam 212, and a rocker arm 213. The transmission wheel set 211 is belt driven by the output end of the drive component 11. The output end of the transmission wheel set 211 is coaxially arranged with the transmission cam 212. The transmission cam 212 is movably connected to one end of the rocker arm 213, and the other end of the rocker arm 213 is movably connected to the lower end face of the rocker frame 23.

[0051] In this embodiment, the side of the screening seat 24 is hinged to the rocker frame 23, and a spring assembly 8 is also provided on the side of the screening seat 24 away from the hinge end.

[0052] In this embodiment, the air inlets of the blowing airbag 51 are arranged opposite each other and are connected by a pipe. The blowing nozzle array 52 includes a blowing nozzle tube 521, which is connected to the pipe by a one-way valve.

[0053] In this embodiment, the nozzle array 52 further includes a plurality of sieve nozzles 522, which are evenly distributed on the nozzle tube 521 at intervals, so as to reciprocate the airflow at the second sieve opening 41 by the volume change of the sieve airbag 51.

[0054] In this embodiment, the second screening component 4 includes an inclined screening channel 42.

[0055] In this embodiment, the screening device further includes a third screening component 9, which is disposed within the screening channel 42.

[0056] In this embodiment, the third screening component 9 includes a screening perforated plate 91, on which a plurality of holes matching the size of rapeseed are formed.

[0057] In this embodiment, a screening hopper 92 is also provided at the end of the screening channel 42, and the screening hopper 92 is also placed below the screening hole plate 91 to form a third screening port 93.

[0058] It should be noted that this embodiment specifically discloses the mechanical structure of a multi-stage rapeseed screening device for clogging prevention. The basic support and power input of the entire device mainly consist of the screening frame 1 placed on the foundation or support platform and the drive assembly 11 installed on it. In actual equipment manufacturing, the screening frame 1 is usually made of a truss frame welded from carbon steel channel steel or spliced ​​with high-strength bolts to ensure the shock resistance and overall rigidity of the equipment during long-term high-frequency operation. The drive assembly 11 serves as the initial power source of the entire equipment and can specifically be a variable frequency asynchronous motor or a servo motor with a reducer, so that the operator can flexibly adjust the output speed and excitation frequency according to the impurity content of different batches of rapeseed.

[0059] At the power output end of the drive assembly 11, the swing assembly 2 is connected. The swing assembly 2 is formed by the mutual connection of the transmission component 21, the transmission rod 22, and the swing frame 23. Specifically, the input end of the transmission component 21 is directly connected to the output shaft of the drive assembly 11, or through a flexible coupling or pulley. In specific embodiments, the transmission component 21 can adopt an eccentric wheel mechanism, a crank-slider mechanism, or a cam-pushing mechanism. Its core function is to convert the continuous rotational motion of the drive assembly 11 into a reciprocating motion of a specific stroke. The output end of the transmission component 21 is hinged to the force-bearing side of the swing frame 23. Meanwhile, the transmission rod 22, as a constraint on the motion trajectory, has its two ends hinged between the fixed screening frame 1 and the movable swing frame 23 through a rotating shaft or a spherical universal joint. When the equipment is running, the transmission component 21 drives the swing frame 23 to produce displacement, while the transmission rod 22 uses its fixed length characteristic to physically guide the motion trajectory of the swing frame 23, forcing the swing frame 23 to periodically reciprocate within a set spatial range.

[0060] On the upper surface of the swing frame 23, a screening seat 24 is movably mounted, directly responsible for carrying and processing materials. The internal structure of the screening seat 24 is hollow, thus forming a semi-enclosed screening chamber 25 for accommodating material movement. To achieve continuous industrial operation, a feed inlet 6 is provided at the top of the screening seat 24, through which rapeseed raw materials mixed with impurities are continuously fed. As the swing frame 23 drives the screening seat 24 to swing back and forth, the material is forced to be thrown and spread within the screening chamber 25 and conveyed to the second screening port 41 according to the angle of inclination and inertia. The two openings of the screening chamber 25 along the material conveying direction are defined as the first screening port 31 and the second screening port 41, respectively, and the first screening component 3 and the second screening component 4 are assembled at the corresponding positions.

[0061] The blowing screen assembly 5 mainly consists of a plastic blowing airbag 51 and a nozzle array 52. ​​The blowing airbag 51 is arranged between the swing frame 23 and the screening seat 24, which have a relative motion tendency. In terms of material selection, the blowing airbag 51 is usually made of polyurethane corrugated bag with excellent fatigue resistance and rebound memory or industrial-grade silicone folding airbag. Its working principle is that when the swing frame 23 swings back and forth under the drive of the transmission component 21, due to the time lag of power transmission, the inertial reaction force of the swing frame 23, and the gap of the movable connecting mechanism, the screening seat 24 and the swing frame 23 will periodically approach and move away from each other. This mechanical relative displacement directly acts on the blowing airbag 51 sandwiched between the two, forming alternating physical compression and stretching, thereby forcing the internal volume of the airbag to undergo high-frequency reciprocating changes.

[0062] By utilizing this volume change to convert it into a directional high-pressure airflow, both the inlet and outlet circuits of the air-blowing bladder 51 are equipped with one-way valves to control the unidirectional flow of airflow. Specifically, the one-way valves include one-way valve I 53 and one-way valve II 54. When the bladder is stretched and expanded, the inlet one-way valve I 53 opens under negative pressure, drawing in clean external air. When the bladder is compressed and contracted, the inlet one-way valve I 53 closes, and the outlet one-way valve II 54 is opened by internal positive pressure, instantly pumping compressed air through a rigid or flexible air pipe into the nozzle array 52 installed at the second screening port 41. The nozzle array 52 can specifically consist of multiple flat duckbill-shaped nozzles or continuous slit air knives evenly arranged along the lower surface of the screen, with the airflow direction obliquely upwards, directly hitting the back of the screen.

[0063] More specifically, the air inlet end of the air inlet circuit of the sieve airbag 51 is preferentially connected to a three-way connector. One connector (connector A) of the three-way connector is connected to the sieve airbag 51, and the other connector (connector B) is connected to the one-way valve I 53. The one-way valve I 53 is directed to allow airflow to enter the sieve airbag only, that is, it is directed unidirectionally along the center direction of the sieve airbag 51. In this embodiment, the last connector (connector C) of the three-way connector is not directly connected to the nozzle array 52. ​​Instead, the two connectors C are connected through an air guide pipe and then indirectly connected to the nozzle array 52 through the air guide pipe. The one-way valve II 54 of the air outlet circuit of the sieve airbag 51 is set between the air guide pipe and the nozzle array 52. ​​Through the setting of the air guide pipe, the airflow from the two connectors can be converged and uniformly compressed to the nozzle array 52.

[0064] In some preferred embodiments, the connector C of the three-way connector is connected to the air duct via a corrugated hose. A one-way valve (not shown in the figure) is also provided near the connector C on the corrugated hose, and its conduction direction is unidirectional along the direction of the nozzle array 52.

[0065] Furthermore, it abandons the traditional structural design that requires additional high-pressure blowers or air compressor pipelines, directly converting the mechanical kinetic energy of the screening action itself into pulsed airflow for screen cleaning. Each mechanical screening and throwing action is accompanied by the nozzle array 52 spraying high-speed back-blowing air onto the easily clogged second screening component 4. This pulsed airflow not only forcibly washes away debris physically stuck in the fine mesh, but also forms a localized micro-fluidization state on the screen surface, greatly reducing the static friction and adhesion of rapeseed and tiny debris to the screen holes. Thus, with an extremely compact structure and extremely low energy consumption, it fundamentally alleviates the problem of frequent clogging of small-aperture fine screens.

[0066] In some more preferred and specific embodiments, a belt drive connection is used between the input end of the transmission wheel set 211 and the motor output shaft of the drive assembly 11. Typically, a V-shaped triangular belt with overload slip protection or a synchronous toothed belt with precise transmission ratio and low step loss is selected. The output axis of the transmission wheel set 211 is coaxially and fixedly connected to the transmission cam 212, so that the cam can follow the wheel set to achieve stable rotation after speed reduction and torque increase.

[0067] The eccentric profile or eccentric pin of the transmission cam 212 forms a movable hinge with one end of the rocker arm 213 (for example, by assembling a cam-driven roller bearing to achieve a low-friction connection), while the other end of the rocker arm 213 is movably connected to the lower end face of the rocker frame 23 by a high-strength pin. When the motor is running, the rotational power is flexibly transmitted to the transmission cam 212 through the belt, and the eccentricity of the cam is used to force the rocker arm 213 to generate spatial linkage motion, thereby driving the rocker frame 23 to periodically swing according to the set stroke and frequency in a purely rigid mechanical guiding manner.

[0068] One lower edge of the screening seat 24 is hinged to the corresponding side of the swing frame 23 via a through hinge shaft, forming a mechanical fulcrum with a relatively fixed spatial position but allowing rotation and opening; while on the bottom of the other side of the screening seat 24 away from the hinge end, a spring assembly 8 is arranged as a flexible support unit. In practical applications, the spring assembly 8 can be selected from multiple sets of parallel heavy-duty cylindrical helical compression springs or polyurethane composite damping blocks with excellent vibration absorption performance.

[0069] During operation, when the bottom swing frame 23 is forcefully driven by the transmission mechanism, due to the structural inertia of the screening seat 24 itself and the gravity compression of the rapeseed material inside, the side supported by the spring assembly 8 will lag behind the movement of the swing frame 23, forcing the spring assembly 8 to passively generate alternating compression and extension deformation. This phase difference based on inertia and elastic restoring force amplifies the vibration acceleration of the suspended end of the screening seat 24, enabling the rapeseed to achieve a higher amplitude throwing and jumping motion. On the other hand, the periodic opening and closing angle change formed between the screening seat 24 and the swing frame 23 provides a physical compression and stretching power source for the blowing airbag 51 sandwiched between the two, with amplitude and frequency synchronized with the mechanical screening action.

[0070] The air inlets of the airbags 51 are arranged opposite each other and are interconnected through wear-resistant and pressure-resistant air guide pipes to form an internal buffer confluence chamber with balanced air pressure between the airbag groups. At the air outlet, the nozzle array 52 mainly consists of a nozzle pipe 521 spanning the width of the screening screen and several air nozzles 522 arranged on it. The nozzle pipe 521 and the aforementioned confluence pipe are connected by a one-way valve II 54 to maintain airflow communication. To ensure the uniformity of coverage and penetration of the pulse screen cleaning airflow, the several air nozzles 522 are evenly distributed at equal intervals along the axial direction of the nozzle pipe 521.

[0071] The flexible air duct can be a PVC pneumatic hose with embedded steel wire, while the blowing nozzle 522 is preferably a flat duckbill-type nozzle with a converging acceleration nozzle. When the blowing airbag 51 is violently squeezed by the relative closing motion of the spring assembly 8 and the swing frame 23, the inside of the pipeline is pressurized instantly, the one-way valve II 54 is quickly opened, and the high-pressure airflow is forced into the blowing nozzle pipe 521. Finally, the various distributed blowing nozzles 522 spray out a strong reciprocating pulse airflow from the back of the second screening port 41, which is prone to blockage. This array-type air path distribution not only transforms the single-point concentrated air pressure into a full-width air knife flush, but also ensures that the wind can cover the bottom of the screen without dead angles, accurately blowing away the fine dust and shriveled seeds embedded in the mesh.

[0072] Both the first screening component 3 and the second screening component 4 employ a physical interception structure composed of several screening plates 7. The screening plates 7 of the first screening component 3 are arranged at an angle within the chamber. This inclined arrangement, resembling louvers or stepped grids, allows large-diameter impurities such as coarse, irregularly shaped straw and broken pods to slide down the inclined surface and be discharged quickly using the component of gravity, while allowing spherical rapeseed and finer impurities to fall smoothly through the screen. After primary impurity removal, the material enters the lower refining area. At this point, the second screening component 4 is a screening channel 42 with an inclined angle, and a third screening component 9 is nested inside this channel. The third screening component 9 is preferably a screening perforated plate 91. The surface of the perforated plate is densely covered with holes that are precisely punched or laser-cut according to the geometric outer diameter of standard mature rapeseed. When the rapeseed group mixed with mud, sand and shriveled grains enters the screening channel 42, under the combined action of the high-frequency mechanical throwing of the screening seat 24 and the pulsed airflow of the bottom blowing nozzle 522, the remaining impurities smaller than the diameter of the holes continue to pass through the holes and the third screening port 93 for separation, while the plump rapeseed with the same size and height are separated along the second screening port 41 on the screening channel 42.

[0073] The above are merely preferred embodiments of this utility model and do not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the description and drawings of this utility model, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A multi-stage rapeseed screening device for clogging prevention, characterized in that, The screening device includes: A screening frame, on which a drive assembly is provided; A swaying assembly includes a transmission component, a transmission rod, and a swaying frame. The input end of the transmission component is connected to the output end of the drive component, and the output end of the transmission component is connected to the swaying frame. Both ends of the transmission rod are connected to the screening frame and the swaying frame, respectively. A screening seat is movably disposed on the upper end surface of the swaying frame. The screening seat is hollow inside and forms a screening chamber. A feed inlet is disposed on the upper end surface of the screening seat. The two openings of the screening chamber are a first screening port and a second screening port, respectively. A first screening component is disposed at a first screening port; The second screening component is disposed at the second screening port; A blowing sieve assembly includes a blowing sieve airbag and a nozzle array. The blowing sieve airbag is disposed between a swing frame and a sieve seat. The nozzle array is disposed at a second sieve port. The air inlet of the blowing sieve airbag is provided with a one-way valve, and the air outlet of the blowing sieve airbag is connected to the nozzle array through the one-way valve.

2. A multi-stage rapeseed screening device against clogging according to claim 1, characterized in that, Both the first screening component and the second screening component include a plurality of screening plates, which are disposed in the screening chamber, and the screening plates of the first screening component are inclined.

3. A multi-stage rapeseed screening device against clogging according to claim 1, characterized in that, The transmission component includes a transmission wheel set, a transmission cam, and a rocker arm. The transmission wheel set is connected to the output end of the drive assembly via belt drive. The output end of the transmission wheel set is coaxially arranged with the transmission cam. The transmission cam is movably connected to one end of the rocker arm, and the other end of the rocker arm is movably connected to the lower end face of the rocker frame.

4. A multi-stage rapeseed screening device against clogging according to claim 1, characterized in that, The side of the screening seat is hinged to the rocking frame, and a spring assembly is also provided on the side of the screening seat away from the hinge end.

5. A multi-stage rapeseed screening device against clogging according to claim 1, characterized in that, The air inlets of the blowing airbags are arranged opposite each other and are connected by a pipe. The nozzle array includes a nozzle tube, and the nozzle tube is connected to the pipe by a one-way valve.

6. The anti-clogging multi-stage rapeseed screening device as described in claim 5, characterized in that, The nozzle array also includes several sieve nozzles, which are evenly distributed on the nozzle tube at intervals to reciprocate the airflow at the second sieve opening by changing the volume of the sieve airbag.

7. A multi-stage rapeseed screening device against clogging according to claim 1, characterized in that, The second screening component includes an inclined screening channel.

8. A multi-stage rapeseed screening device against clogging according to claim 7, characterized in that, The screening device further includes a third screening component, which is disposed within the screening channel.

9. A multi-stage rapeseed screening device against clogging according to claim 8, characterised in that, The third screening component includes a screening perforated plate, which has a plurality of holes that match the size of the rapeseed.

10. A multi-stage rapeseed screening device against clogging according to claim 9, characterized in that, The end of the screening channel is also provided with a screening hopper, and the screening hopper is also placed below the screening orifice plate to form a third screening port.

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