Multi-stage screening and binning unloading device for wheat

Abstract

This invention relates to the field of wheat screening and feeding devices, specifically a multi-stage wheat screening and feeding device. It includes a temporary storage bin slidably disposed at the bottom of a feeding chamber, a fine screening cylinder fixedly installed at the top of the feeding chamber, and an air-separation impurity removal pipe assembly installed between the lower part of the fine screening cylinder and the top of the feeding chamber. It also includes a coarse screen fixedly installed at the top of the fine screening cylinder. A support is installed inside the fine screening cylinder, and a fine screening mechanism is movably installed between the upper part of the support and the lower end of the coarse screen. A multi-screening position switching mechanism is movably installed at the lower part of the support and cooperates with the fine screening mechanism. This multi-stage wheat screening and feeding device forms an annular material curtain through the guiding cone sleeve, and, in conjunction with the air-separation impurity removal pipe assembly and dust suction hood, achieves air-separation fine screening and impurity removal. This fundamentally avoids problems such as screen clogging, screen sticking, wear and deformation, and holes, eliminating the need for frequent shutdowns for manual screen cleaning and replacement, effectively improving the continuous operation capability of the equipment and reducing equipment maintenance costs.

Description

Technical Field

[0001] This invention relates to the field of wheat screening and feeding devices, specifically a multi-stage wheat screening and silo feeding device. Background Technology

[0002] Wheat is the core raw material for flour processing. Before milling, it must undergo pre-processing steps such as multi-stage screening, air separation for impurity removal, temporary storage in separate bins, and precise feeding. The multi-stage screening and feeding device for wheat is a key piece of equipment in the grain processing pre-processing section. Existing similar devices generally have a temporary storage bin sliding in the lower part of the bin room, a fine screening cylinder fixed at the top, a coarse screen at the upper end of the fine screening cylinder, and are equipped with air separation for impurity removal pipe groups and dust suction hoods on the inner wall to complete the coarse screening, fine screening, and feeding of wheat.

[0003] The following problems exist in the existing technology that have not been adequately addressed: 1. Current fine screening operations generally use fixed screens as the core grading element. When wheat contains dust, is damp and clumps together, or contains wheat awns and debris, it is very easy to cause screen blockage and clogging. Long-term exposure to material scouring and equipment vibration can easily cause the screen to wear, deform, or even break, which not only causes fine screening and grading failure, but also requires frequent shutdowns for manual cleaning and screen replacement. The equipment has poor continuous operation capability and high maintenance costs. 2. Traditional equipment lacks adaptive discharge expansion and multi-screen diversion structures. When increasing the wheat feed rate to improve production capacity, material accumulation and blockage problems easily occur at the discharge end of the coarse screen. It cannot automatically increase the discharge gap and form a double-layer material curtain for diversion screening. At the same time, the air path cannot automatically switch between positive and negative pressure modes according to the material accumulation conditions, which cannot match the differentiated dust removal requirements of normal fine screening and high-flow screening, making it difficult to simultaneously achieve both screening accuracy and operating efficiency. Summary of the Invention

[0004] The purpose of this invention is to provide a multi-stage wheat screening and discharging device to solve the problems mentioned in the background art. To achieve the above objective, this invention provides the following technical solution: a multi-stage wheat screening and discharging device, comprising a temporary storage bin slidably disposed at the lower part of the discharging chamber, a fine screening cylinder fixedly installed at the top of the discharging chamber, and an air separation and impurity removal pipe assembly installed between the lower part of the fine screening cylinder and the top of the discharging chamber;

[0005] It also includes a coarse screener fixedly installed on the top of the fine screen cylinder, a support installed inside the fine screen cylinder, and a fine screening mechanism movably installed between the upper part of the support and the lower end of the coarse screener.

[0006] The multi-screen switching mechanism, which is installed at the bottom of the support and works with the fine screening mechanism, is used to increase the screening positions and prevent material accumulation.

[0007] Preferably, the fine screening mechanism includes: a guide cone sleeve that is vertically slidably disposed on the top of the support, and the top of the guide cone sleeve extends into the outlet end of the coarse screen to guide the material discharged from the coarse screen to form a material curtain;

[0008] Three flow dividers are equidistantly opened at the top of the flow guide cone sleeve along the circumference, and a baffle is vertically slidably arranged inside the flow divider. A top rod is vertically slidably arranged inside the flow guide cone sleeve to restrict the downward movement of the baffle. The lower part of the top rod is inserted into the bottom of the flow guide cone sleeve.

[0009] A three-way valve is fixedly installed inside the support. The two ends of the lower part of the three-way valve are connected to the air separation and impurity removal pipe group. The top of the three-way valve is set at the axial position at the bottom of the guide cone sleeve. The adjusting end of the three-way valve is movably connected to the multi-screen switching mechanism.

[0010] A dust-collecting hood is fixedly installed on the inner wall of the fine sieve cylinder and connected to the air separation and impurity removal pipe assembly.

[0011] Preferably, the discharge end at the bottom of the coarse screen is configured as a conical surface that mates with the top of the guide cone sleeve;

[0012] The inner wall of the guide cone sleeve is provided with a movable groove for the vertical sliding of the push rod, and a movable ring is fixedly sleeved on the surface of the push rod. A movable spring is fixedly connected between the top of the movable ring and the inner wall of the movable groove.

[0013] Preferably, the three-way valve is an electromagnetic three-way ball valve, with ventilation pipes connected to both ends of the lower part of the three-way valve. The ventilation pipes are fixedly assembled with the support. The left end of the lower part of the three-way valve is connected to the positive pressure end of the air separation and impurity removal pipe group, and the right end of the lower part of the three-way valve is connected to the negative pressure end of the air separation and impurity removal pipe group.

[0014] Preferably, the bottom of the flow guide cone sleeve is cone-shaped, the top of the support is a cone surface that matches the bottom of the flow guide cone sleeve, and a through hole that matches the top of the three-way valve is opened at the center of the cone surface. A filter screen ring is fixedly connected to the bottom of the flow guide cone sleeve, and the filter screen ring is sleeved on the outer ring of the support.

[0015] Preferably, the multi-screen switching mechanism includes: a plurality of guide rods vertically slidably disposed on the top of the support, and a return spring is movably connected between the lower part of the guide rod and the inner wall of the support; the top of the guide rod is fixedly connected to the bottom of the guide cone sleeve.

[0016] A press regulator is fixedly installed at the adjustment end of a three-way valve, and the trigger end of the press regulator is coaxially aligned with the corresponding guide rod.

[0017] Preferably, the support has three guide grooves equidistantly spaced along the circumference inside. The number of guide rods is the same as the number of guide grooves and they correspond one-to-one. A limit ring is fixedly sleeved on the surface of the guide rod, and a reset spring is disposed between the top of the limit ring and the inner wall of the guide groove.

[0018] Preferably, the air separation and impurity removal pipe assembly consists of a positive pressure air duct and a negative pressure air duct, and is used to remove foreign objects during the coarse and fine screening of wheat.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] In this invention, a ring-shaped material curtain is formed by guiding the flow through the conical surface of the guide cone sleeve. Combined with the air separation and impurity removal pipe assembly and the dust suction hood, air separation fine screening and impurity removal are achieved. This fundamentally avoids problems such as screen blockage, screen clogging, wear and deformation and holes. There is no need for frequent machine shutdowns for manual screen cleaning and replacement, which effectively improves the continuous operation capability of the equipment and reduces equipment maintenance costs and manual maintenance workload.

[0021] In this invention, a three-way valve is used to guide positive pressure airflow, which forms an annular airflow field through the conical gap between the guide cone sleeve and the support. This can deeply peel off the dust and fine wheat fragments trapped inside the material curtain. Combined with the dust extraction hood for surface dust removal, this invention breaks through the limitation of traditional single dust extraction which can only clean impurities on the surface of the material curtain. The air separation and impurity removal is more comprehensive and thorough, significantly improving the quality of wheat screening and purification.

[0022] In this invention, the guide cone sleeve is driven to move downward adaptively by the self-weight pressure of the accumulated material, automatically increasing the discharge gap and forming an inner and outer double-layer material curtain through the diversion channel, realizing multi-screen diversion operation, effectively guiding material accumulation and avoiding material blockage and machine shutdown. At the same time, the guide rod is linked to the press regulator to trigger the electromagnetic three-way ball valve to automatically switch the positive and negative pressure air paths, which can be adapted to two working conditions: normal fine screening and quality improvement, and high-flow screening and efficiency improvement. It can flexibly balance the wheat screening accuracy and equipment operation efficiency. Attached Figure Description

[0023] Figure 1 This is a perspective view showing the positions of the temporary material distribution bin and the fine sieve cylinder in this invention;

[0024] Figure 2 This is a cross-sectional view of a portion of the fine sieve cylinder and the coarse sieve of the present invention;

[0025] Figure 3 This is a cross-sectional view of a portion of the flow guide cone sleeve and filter ring of the present invention;

[0026] Figure 4 This is an exploded view of the flow guide cone sleeve and support of the present invention;

[0027] Figure 5 This is a cross-sectional view of a portion of the flow guide cone sleeve and the flow divider groove of the present invention;

[0028] Figure 6 This is a cross-sectional view of a portion of the partition and diversion channel of the present invention;

[0029] Figure 7 For the present invention Figure 6 Enlarged view of the structure at point A in the middle;

[0030] Figure 8 This is a cross-sectional view of a portion of the support and three-way valve of the present invention;

[0031] Figure 9 For the present invention Figure 8 Enlarged view of the structure at point B;

[0032] Figure 10 This is a perspective view of the three-way valve and pressure regulator of the present invention.

[0033] In the diagram: 1. Temporary storage bin; 2. Fine screening cylinder; 3. Air separation and impurity removal pipe assembly; 4. Coarse screen; 5. Support; 6. Fine screening mechanism; 601. Guide cone sleeve; 602. Diversion groove; 603. Baffle plate; 604. Top rod; 605. Three-way valve; 606. Dust extraction hood; 607. Movable groove; 608. Movable spring; 609. Ventilation pipe; 610. Through hole; 611. Filter ring; 7. Multi-screen switching mechanism; 701. Guide rod; 702. Reset spring; 703. Press adjuster; 704. Guide groove; 705. Limiting ring. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] Please see Figures 1 to 10 This invention provides a technical solution: a multi-stage wheat screening and silo-discharging device, comprising a temporary storage silo 1 slidably disposed at the bottom of a silo chamber, a fine screening cylinder 2 fixedly installed at the top of the silo chamber, and an air-separation impurity removal pipe assembly 3 installed between the lower part of the fine screening cylinder 2 and the top of the silo chamber. It should be noted that wheat screening and silo-discharging are typically carried out in the silo chamber, with a discharge port at the bottom of the silo chamber. The wheat to be unloaded is guided from the corresponding position of the fine screening cylinder 2 into the discharge port at its bottom through the temporary storage silo 1 to achieve silo-discharging processing.

[0036] It also includes a coarse screener 4 fixedly installed on top of the fine screen cylinder 2. A support 5 is installed inside the fine screen cylinder 2, and a fine screening mechanism 6 is movably installed between the upper part of the support 5 and the lower end of the coarse screener 4. It should be noted that the coarse screener 4 processes large particles of impurities in the wheat conveyed inside, and achieves preliminary screening in cooperation with the air separation and impurity removal tube group 3. Here, the coarse screener 4 is an existing device in the multi-stage screening process of wheat, and will not be described in detail.

[0037] The multi-screen switching mechanism 7, which is installed on the lower part of the support 5 and cooperates with the fine screening mechanism 6, is used to increase the screening positions and avoid material accumulation.

[0038] In this embodiment, as Figures 1 to 10 As shown, the fine screening mechanism 6 includes a guide cone sleeve 601 that is vertically slidably disposed on the top of the support 5, and the top of the guide cone sleeve 601 extends into the outlet end of the coarse screen 4 to guide the material discharged from the coarse screen 4 to form a material curtain.

[0039] Three flow dividers 602 are equidistantly opened on the top of the flow guide cone sleeve 601 along the circumference, and a baffle 603 is vertically slidably arranged inside the flow divider 602. A push rod 604 is vertically slidably arranged inside the flow guide cone sleeve 601 to restrict the downward movement of the baffle 603. The lower part of the push rod 604 is inserted into the bottom of the flow guide cone sleeve 601. It should be noted that: the top of the top rod 604 is fixedly connected to the bottom of the partition plate 603, and the top rod 604 is symmetrically arranged at the bottom of the partition plate 603 to guide and position the movement of the partition plate 603; when it is necessary to improve the screening efficiency, the material conveying efficiency is improved. At this time, when the material at the top of the guide cone sleeve 601 and the outlet of the coarse screen 4 accumulates, the pressure of the material drives the guide cone sleeve 601 to move down at the top of the support 5. Under the restriction of the top rod 604, the partition plate 603 will not move down synchronously with the guide cone sleeve 601, so that the diversion groove 602 of the guide cone sleeve 601 is exposed. At this time, the excess material is discharged from the position of the diversion groove 602, so that two layers of material curtain are formed at the bottom of the guide cone sleeve 601, switching to multi-screen mode to improve screening efficiency.

[0040] A three-way valve 605 is fixedly installed inside the support 5. The lower two ends of the three-way valve 605 are connected to the air-separation and impurity removal pipe assembly 3. The top of the three-way valve 605 is located at the axial center of the bottom of the guide cone sleeve 601. The adjusting end of the three-way valve 605 is movably connected to the multi-screen switching mechanism 7. It should be noted that the mating contact surface between the baffle 603 and the diversion channel 602 is designed as a conical guide surface. Utilizing the self-centering effect of the conical surface, material jamming is prevented during the baffle's resetting and sealing process.

[0041] A dust-collecting hood 606 is fixedly installed on the inner wall of the fine screening cylinder 2 and connected to the air separation and impurity removal pipe assembly 3. It should be noted that the dust-collecting hood 606 is arranged in a ring on the inner wall of the fine screening cylinder 2 to collect dust from the material curtain around the guide cone sleeve 601 and remove dust from the wheat.

[0042] In this embodiment, as Figures 1 to 10 As shown, the discharge end at the bottom of the coarse screen 4 is designed with a conical surface that mates with the top of the guide cone sleeve 601. It should be noted that the conical surface design allows the material between the coarse screen 4 and the guide cone sleeve 601 to slide down along the conical surface, forming an annular material curtain that falls and cooperates with the dust extraction hood 606 to achieve fine screening. This avoids the need for a filter screen for fine screening, which could cause filter screen clogging and improve screening efficiency.

[0043] The inner wall of the guide cone sleeve 601 is provided with a movable groove 607 for the vertical sliding of the push rod 604, and a movable ring is fixedly sleeved on the surface of the push rod 604. A movable spring 608 is fixedly connected between the top of the movable ring and the inner wall of the movable groove 607.

[0044] In this embodiment, as Figures 1 to 10 As shown, the three-way valve 605 is an electromagnetic three-way ball valve. Both ends of the lower part of the three-way valve 605 are connected to ventilation pipes 609, which are fixedly assembled with the support 5. The left end of the lower part of the three-way valve 605 is connected to the positive pressure end of the air separation and impurity removal pipe group 3, and the right end of the lower part of the three-way valve 605 is connected to the negative pressure end of the air separation and impurity removal pipe group 3. It should be noted that the two ventilation pipes 609 confine the stable support 5 inside the fine screen cylinder 2. The three-way valve 605 can cooperate with the air separation and impurity removal pipe group 3 to switch between positive and negative pressure air pipes, thereby achieving the switching between blowing and suction states. During blowing, it can assist the dust suction hood 606 in high-quality dust removal, improving screening quality; during suction, it can effectively remove dust from the second layer of material curtain, improving screening efficiency.

[0045] In this embodiment, as Figures 1 to 10 As shown, the bottom of the guide cone sleeve 601 is cone-shaped, and the top of the support 5 is a cone surface that mates with the bottom of the guide cone sleeve 601. A through hole 610, mates with the top of the three-way valve 605, is provided at the center of the cone surface. It should be noted that the cone-shaped gap formed between the bottom of the guide cone sleeve 601 and the top of the support 5 guides and disperses the airflow, ensuring that the airflow is evenly distributed around the material curtain and guaranteeing effective dust removal.

[0046] A filter ring 611 is fixedly connected to the bottom of the guide cone sleeve 601, and the filter ring 611 is fitted onto the outer ring of the support 5. It should be noted that the filter ring is located in the inner ring formed by the three diversion channels 602, which isolates the material curtain discharged from the diversion channels 602 to prevent wheat particles from entering the three-way valve 605. At the same time, it does not obstruct dust and fine wheat particles from being sucked into the dust removal system by negative pressure with the airflow, thus protecting the valve body without affecting the air classification dust removal effect. The filter ring 611 is not the traditional main screen for material classification and interception screening, but only serves as an isolation fence for preventing wheat particles from splashing through the central through hole and as an auxiliary component for airflow guidance.

[0047] In this embodiment, as Figures 1 to 10 As shown, the multi-screen switching mechanism includes: several guide rods 701 that are vertically slidably disposed on the top of the support 5, and a return spring 702 is movably connected between the lower part of the guide rod 701 and the inner wall of the support 5, and the top of the guide rod 701 is fixedly connected to the bottom of the guide cone sleeve 601.

[0048] A pressure regulator 703 is fixedly installed on the adjusting end of the three-way valve 605. The trigger end of the pressure regulator 703 is coaxially aligned with the corresponding guide rod 701. It should be noted that the pressure regulator 703 is electrically connected to the adjusting end of the three-way valve 605. When the guide cone sleeve 601 moves downward with the guide rod 701, the guide rod 701 contacts the pressure regulator 703, causing the pressurized pressure regulator 703 to drive the adjusting end of the three-way valve 605 to operate, switching the operating mode of the three-way valve 605 from suction to blowing.

[0049] In this embodiment, as Figures 1 to 10 As shown, the support 5 has three guide grooves 704 equidistantly spaced along the circumference inside. The number of guide rods 701 is the same as that of guide grooves 704 and they correspond one-to-one. A limit ring 705 is fixedly sleeved on the surface of the guide rod 701. A reset spring 702 is set between the top of the limit ring 705 and the inner wall of the guide groove 704.

[0050] In this embodiment, as Figures 1 to 10 As shown, the air-separation and impurity removal pipe assembly 3 consists of a positive pressure air duct and a negative pressure air duct. The air-separation and impurity removal pipe assembly 3 is used to remove foreign objects during the coarse and fine screening of wheat. It should be noted that the air-separation and impurity removal pipe assembly 3 is existing technology in multi-stage wheat screening devices, and will not be described in detail here.

[0051] The method of use and advantages of this invention: The working process of this multi-stage wheat screening and silo feeding device is as follows:

[0052] like Figures 1 to 10 As shown, during the operation of the equipment, the control temporary storage bin 1 is moved horizontally inside the bin to the corresponding position at the bottom of the fine screening cylinder 2 to be unloaded, and the coarse screen 4 and the air separation and impurity removal pipe group 3 are started simultaneously to complete the multi-stage screening operation of wheat materials.

[0053] When it is necessary to improve the quality of impurity removal, the amount of wheat conveyed is controlled. After the wheat is screened by the coarse screener 4 to remove large particles of impurities, it falls from the bottom of the coarse screener 4 to the top surface of the guide cone sleeve 601. Under the guiding and diversion action of the cone surface of the guide cone sleeve 601, the material falls evenly along the circumference of the guide cone sleeve 601 and forms an annular material curtain. At this time, the dust suction hood 606 installed on the inner wall of the fine screen cylinder 2 can suck and separate the dust and fine broken wheat wrapped on the surface of the annular material curtain. At the same time, the left end of the three-way valve 605 is kept in the conductive state with the top passage. The positive pressure airflow generated inside the air separation and impurity removal pipe group 3 is blown from the top of the support 5 to the bottom cone surface of the guide cone sleeve 601. The airflow follows the flow path of the cone surface and is discharged outward through the gap between the guide cone sleeve 601 and the support 5, forming an annular airflow field, which helps to peel off and discharge the dust and foreign objects mixed in the annular material curtain, significantly improving the overall effect of wheat screening and impurity removal.

[0054] When it is necessary to improve screening efficiency, the wheat conveying capacity is increased. At this time, material accumulates between the bottom of the coarse screen 4 and the guide cone sleeve 601. Under the pressure of the wheat material's own weight, the guide cone sleeve 601 moves downward along the top of the support 5. The material drop gap between the top of the guide cone sleeve 601 and the bottom of the coarse screen 4 increases accordingly, effectively increasing the discharge throughput at the bottom of the coarse screen 4. During the downward movement of the guide cone sleeve 601, the top rod 604 is driven downward simultaneously. The bottom of the top rod 604 is constrained by the structure of the support 5, which in turn locks the vertical displacement of the partition 603. The downward-moving guide cone sleeve 601 and the partition 603 in the constrained state are relatively separated. As the discharge capacity continues to increase, the excess material overflows from the diversion channel 602 and is discharged, eventually forming an inner and outer two-layer material curtain below the guide cone sleeve 601.

[0055] At the same time, when the guide cone sleeve 601 moves down to the preset limit stroke, the guide cone sleeve 601 and the guide rod 701 press against the corresponding pressing regulator 703. The pressing regulator 703 drives the control end of the three-way valve 605 to complete the passage switching, realizing the left passage of the three-way valve 605 is closed and the right passage is opened. At this time, the air separation and impurity removal pipe group 3 switches to negative pressure airflow mode. Through the action of the right end and the top passage of the three-way valve 605, the double-layer material curtain discharged from the diversion channel 602 is subjected to full-area negative pressure dust removal, thereby improving the screening operation throughput and operation efficiency while ensuring the dust removal effect.

[0056] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A multi-stage screening and discharging device for wheat, including a temporary storage bin (1) that is slidably disposed at the bottom of the compartment, a fine screen cylinder (2) that is fixedly installed at the top of the compartment, and an air separation and impurity removal pipe assembly (3) installed between the bottom of the fine screen cylinder (2) and the top of the compartment. Its features are, It also includes a coarse screener (4) fixedly installed on the top of the fine screen cylinder (2), a support (5) is installed inside the fine screen cylinder (2), and a fine screening mechanism (6) is movably installed between the upper part of the support (5) and the lower end of the coarse screener (4). The multi-screen switching mechanism (7) is installed on the lower part of the support (5) and cooperates with the fine screening mechanism (6) to increase the screening position and avoid material accumulation.

2. The wheat multi-stage screening and silo feeding device according to claim 1, characterized in that: The fine screening mechanism (6) includes: a guide cone sleeve (601) that is vertically slidably disposed on the top of the support (5), and the top of the guide cone sleeve (601) extends into the outlet end of the coarse screen (4) to guide the material discharged from the coarse screen (4) to form a material curtain; Three flow dividers (602) are equidistantly opened on the top of the flow guide cone sleeve (601) along the circumference, and a partition (603) is vertically slidably arranged inside the flow divider (602). A top rod (604) is vertically slidably arranged inside the flow guide cone sleeve (601) to restrict the downward movement of the partition (603). The lower part of the top rod (604) is inserted into the bottom of the flow guide cone sleeve (601). A three-way valve (605) is fixedly installed inside the support (5). The two ends of the lower part of the three-way valve (605) are connected to the air separation and impurity removal pipe group (3). The top of the three-way valve (605) is set at the axial position at the bottom of the guide cone sleeve (601). The adjustment end of the three-way valve (605) is movably connected to the multi-screen position switching mechanism (7). A dust-collecting hood (606) is fixedly installed on the inner wall of the fine screen cylinder (2) and connected to the air separation and impurity removal pipe group (3).

3. The wheat multi-stage screening and silo feeding device according to claim 2, characterized in that: The discharge end at the bottom of the coarse screen (4) is set as a conical surface that matches the top of the guide cone sleeve (601); The inner wall of the guide cone sleeve (601) is provided with a movable groove (607) for the vertical sliding of the push rod (604), and a movable ring is fixedly sleeved on the surface of the push rod (604). A movable spring (608) is fixedly connected between the top of the movable ring and the inner wall of the movable groove (607).

4. The wheat multi-stage screening and silo feeding device according to claim 3, characterized in that: The three-way valve (605) is an electromagnetic three-way ball valve. The two ends of the lower part of the three-way valve (605) are respectively connected to the ventilation pipe (609). The ventilation pipe (609) is fixedly assembled with the support (5). The left end of the lower part of the three-way valve (605) is connected to the positive pressure end of the air separation and impurity removal pipe group (3), and the right end of the lower part of the three-way valve (605) is connected to the negative pressure end of the air separation and impurity removal pipe group (3).

5. The wheat multi-stage screening and silo feeding device according to claim 4, characterized in that: The bottom of the flow guide cone sleeve (601) is cone-shaped, and the top of the support (5) is a cone surface that matches the bottom of the flow guide cone sleeve (601). A through hole (610) that matches the top of the three-way valve (605) is opened at the center of the cone surface. A filter ring (611) is fixedly connected to the bottom of the flow guide cone sleeve (601), and the filter ring (611) is sleeved on the outer ring of the support (5).

6. The wheat multi-stage screening and silo feeding device according to claim 5, characterized in that: The multi-screen switching mechanism includes: a plurality of guide rods (701) that are vertically slidably disposed on the top of the support (5), and a return spring (702) is movably connected between the lower part of the guide rod (701) and the inner wall of the support (5), and the top of the guide rod (701) is fixedly connected to the bottom of the flow guide cone sleeve (601). A press regulator (703) is fixedly installed on the adjusting end of the three-way valve (605). The trigger end of the press regulator (703) is coaxially aligned with the corresponding guide rod (701).

7. The wheat multi-stage screening and silo feeding device according to claim 6, characterized in that: The support (5) has three guide grooves (704) equidistantly spaced along the circumference inside. The number of guide rods (701) is the same as that of guide grooves (704) and they correspond one to one. A limit ring (705) is fixedly sleeved on the surface of the guide rod (701). A reset spring (702) is set between the top of the limit ring (705) and the inner wall of the guide groove (704).

8. The wheat multi-stage screening and silo feeding device according to claim 7, characterized in that: The air separation and impurity removal pipe group (3) consists of a positive pressure air duct and a negative pressure air duct. The air separation and impurity removal pipe group (3) is used to remove foreign objects in the coarse and fine screening of wheat.

Images