Flexible grain pneumatic conveying system

Abstract

The utility model provides a flexible grain pneumatic conveying system, including cyclone separator, have for gas -solid mixture tangential access's inlet, the air outlet of top location and the blanking port of bottom location, gas source device has a negative pressure port and a positive pressure port, air lock is established in below blanking port, is used for in closed state under the transport material, reversing valve and the pipeline system of connecting above -mentioned parts, the application adopts a gas source device and a set of core equipment, realizes two functions'sharp switching of suction material and discharge material through reversing valve, replaces traditional two sets of independent system, greatly simplifies equipment configuration, reduces equipment investment cost and floor space, its suction material mode does not need special feeding equipment, and the discharge material mode utilizes the material collected after suction material, and the whole system integration degree is high, and the process is smooth, reduces the operation link and equipment maintenance point.

Description

Technical Field

[0001] This utility model relates to the field of grain conveying, and in particular to a flexible pneumatic grain conveying system. Background Technology

[0002] Existing pneumatic grain conveying systems are typically single-function. For example, grain suction systems usually use negative pressure to draw grain from grain silos, wagons, etc., into the collection device, but they lack the ability to transport the collected grain over long distances. Grain discharge systems (or positive pressure conveying systems) usually require specialized feeding equipment (such as rotary feeders or screw conveyors) to feed grain into the positive pressure pipeline, making the system complex and costly. To achieve grain suction at one location and grain discharge at another, two independent systems are often needed, requiring a large footprint, high investment costs, cumbersome operation, and complex pipeline switching.

[0003] Furthermore, during the negative pressure grain suction process, the material and airflow enter the cyclone separator together. For materials with high moisture content, such as grains, the moisture can easily cause the grain to stick and clump together on the inner wall of the cone section of the cyclone separator during the airflow's deceleration, forming a blockage and preventing the grain from smoothly passing through the lower discharge port into the airlock. Existing technology typically uses manual or mechanical vibratory hammers to periodically tap the outer wall of the cyclone separator to remove the clumps. This method not only requires additional manpower or power and has inconsistent results, but long-term tapping and vibration can also lead to fatigue, deformation, or even damage to the cyclone separator cylinder, shortening the equipment's service life. Utility Model Content

[0004] The present invention aims to provide a simplified structure, low cost, and dual-purpose anti-clogging pneumatic conveying system.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows: Flexible pneumatic grain conveying system, including: A cyclone separator has an inlet for tangential entry of a gas-solid mixture, an outlet at the top, and a discharge outlet at the bottom. The gas supply device has a negative pressure port and a positive pressure port; An airlock is located below the material inlet and is used to transfer materials in a sealed state. Reversing valve; And the piping system connecting the above components; The piping system includes: A negative pressure pipeline connects the negative pressure port of the gas source device to the air outlet of the cyclone separator. The suction pipe is connected at one end to the inlet of the cyclone separator and at the other end to the reversing valve; The material changing pipe has one end connected to the reversing valve and the other end used to connect to an external silo. The reversing valve has at least two operating states: In the suction state, the reversing valve connects the material exchange pipe to the material suction pipe, so that the material is sucked into the cyclone separator through the negative pressure generated by the air source device via the material exchange pipe, the reversing valve, and the material suction pipe. In the discharge state, the reversing valve connects the material exchange pipeline to the downstream flow path of the airlock. At the same time, high-pressure airflow from the positive pressure port of the air source device is introduced into the downstream of the airlock so that the material discharged through the airlock is blown to the target silo through the reversing valve and the material exchange pipeline.

[0006] Furthermore, it also includes an acceleration chamber, which is disposed between the outlet of the airlock and the reversing valve; in the discharge state, the high-pressure airflow from the positive pressure port of the air source device is introduced into the acceleration chamber, mixes with the material falling from the airlock, and accelerates it.

[0007] Furthermore, the pipeline system also includes a positive pressure pipeline connecting the positive pressure port of the gas source device to the acceleration chamber, for delivering high-pressure airflow to the acceleration chamber in the discharge state.

[0008] Furthermore, the cyclone separator is also equipped with a material-dispensing component, which is used to clean the material adhering to the inner wall of the cyclone separator.

[0009] Furthermore, the feeding assembly includes: The fan blades are rotatably disposed in the airflow channel at the outlet of the cyclone separator and are driven to rotate by the airflow flowing through the outlet. The shaft is connected at its upper end to the fan blades and extends downward into the cylinder of the cyclone separator. At least one feed rod is connected to the connecting shaft and scrapes the inner wall of the cylinder as the connecting shaft rotates.

[0010] Furthermore, the feeding rod is a first feeding rod detachably mounted on the connecting shaft; the connecting shaft has a slot along its axial direction for accommodating the root of the first feeding rod.

[0011] Furthermore, the slot has a dovetail-shaped cross-section, and the root of the first feeding rod has a shape adapted to the dovetail-shaped cross-section; the bottom end of the connecting shaft is also provided with a sealing head for sealing the slot opening.

[0012] Furthermore, the feeding assembly also includes: The first abutting block is slidably sleeved on the connecting shaft along the axial direction, and the material feeding rod is radially installed on the first abutting block; The second abutment block is fixedly disposed inside the cylinder and abuts against the convex surface of the first abutment block. The abutment surface of the second abutment block has a non-planar profile with undulations. An axial spring, sleeved on the connecting shaft, is used to apply axial elastic force to the first abutment block, so that the abutment surfaces of the first abutment block and the second abutment block remain in contact.

[0013] Furthermore, the feeding rod is elastically connected to the first abutment block via a radial spring, so that its end can maintain elastic pressure on the inner wall of the cylinder.

[0014] Furthermore, the cross-section of the feeding rod is rhomboid, and the rod body is also provided with a feeding blade for stirring the material.

[0015] Compared with the prior art, the beneficial effects of this utility model include: 1. This application uses one air source device and one set of core equipment, and realizes flexible switching between the two functions of material suction and material discharge through the reversing valve, which replaces the traditional two independent systems, greatly simplifies the equipment configuration, and reduces the equipment investment cost and floor space.

[0016] 2. The material suction mode of this application does not require dedicated material feeding equipment, while the material discharge mode utilizes the material collected after suction. The whole system has a high degree of integration, a smooth process, and reduces operation steps and equipment maintenance points.

[0017] 3. This application incorporates an airflow-driven material-dispensing component within the cyclone separator, which automatically and continuously cleans the clumps on the inner wall without requiring an additional power source. This solves the technical problem of easy clogging by damp materials, avoids equipment damage caused by manual knocking, and ensures the continuous and stable operation of the system. Attached Figure Description

[0018] The disclosure of this utility model is illustrated with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of this utility model. In the drawings, the same reference numerals are used to refer to the same parts. Wherein: Figure 1 This is a structural diagram of the conveying system.

[0019] Figure 2 for Figure 1 Enlarged view of section C.

[0020] Figure 3 This is the main view of the conveyor system.

[0021] Figure 4 This is a diagram of the internal structure of the cylinder.

[0022] Figure 5 for Figure 4 Enlarged view of section A.

[0023] Figure 6 This is a structural diagram of the material feeding assembly.

[0024] Figure 7 for Figure 6 Enlarged view of section B Figure 8 This is a structural diagram of the second feed bar.

[0025] Numbering on the map: 10. Cyclone separator; 11. Cylinder; 12. Inlet; 13. Outlet; 14. Connector; 15. Drop outlet; 21. Fan blade; 22. Coupling; 23. Support ring; 241. First feeding rod; 242. Slot; 251. Second feeding rod; 252. First abutment block; 253. Second abutment block; 254. Paddle; 255. Cover; 26. End cap; 30. Roots blower; 40. Airlock; 50. Acceleration chamber; 60. Reversing valve; 70. Negative pressure pipeline; 80. Positive pressure pipeline; 90. Suction pipeline; 100. Material changing pipeline; 110. Exhaust three-way valve. Detailed Implementation

[0026] It is readily understood that, based on the technical solution of this utility model, those skilled in the art can propose various interchangeable structural methods and implementations without altering the essential spirit of this utility model. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative descriptions of the technical solution of this utility model and should not be considered as the entirety of this utility model or as limitations or restrictions on the technical solution of this utility model.

[0027] Example 1 This embodiment provides a flexible pneumatic conveying system, such as Figure 1 As shown, it mainly includes a cyclone separator 10, a Roots blower 30, an airlock 40, an acceleration chamber 50, a reversing valve 60, a negative pressure pipeline 70, a positive pressure pipeline 80, a suction pipeline 90, and a material exchange pipeline 100.

[0028] The Roots blower 30, acting as an air source, generates negative pressure at its inlet and positive pressure at its outlet. An airlock 40 is installed below the discharge port 15 of the cyclone separator 10 to ensure the even discharge of separated material while maintaining system airtightness. A reversing valve 60 switches between suction and discharge modes; it can be a three-way or four-way reversing valve.

[0029] The operating mode of this system is as follows: 1. Suction mode When grain needs to be drawn from the first hopper (not shown in the figure), the reversing valve 60 is switched to the suction passage position. At this time, the pipeline connection is as follows: the first hopper is connected to the corresponding reversing valve 60 via the material exchange pipe 100, and this reversing valve 60 is then connected to the suction pipe 90. The Roots blower 30 starts, and its air inlet draws air from the top of the cyclone separator 10 through the negative pressure pipe 70, creating a negative pressure inside the cyclone separator 10. This negative pressure is transmitted to the suction nozzle at the first hopper through the suction pipe 90 and the reversing valve 60.

[0030] Under the influence of a strong pressure difference, the grain is drawn up along with the air, forming a gas-solid two-phase flow. This flow travels at high speed through the material exchange pipe 100, the reversing valve 60, and the suction pipe 90 into the tangential inlet 12 of the cyclone separator 10. Inside the cyclone separator 10, the airflow rotates and slows down. Heavier grain particles, due to centrifugal force and gravity, fall along the cylinder wall to the bottom discharge port 15 and enter the airlock 40. The separated air is extracted from the top outlet 13, enters the inlet of the Roots blower 30 through the negative pressure pipe 70, and finally exits from its outlet.

[0031] The material suction line is as follows: First silo (material source) → material exchange pipe 100 → reversing valve 60 → suction pipe 90 → cyclone separator 10 → airlock 40 → acceleration chamber 50 (the grain is temporarily stored here at this time).

[0032] The airflow path is as follows: First silo → material exchange pipe 100 → reversing valve 60 → suction pipe 90 → cyclone separator 10 → negative pressure pipe 70 → Roots blower 30 → positive pressure pipe 80 → exhaust three-way valve 110 → first silencer chamber (optional) → outside.

[0033] 2. Discharge Mode When enough grain has accumulated in the airlock 40 and acceleration chamber 50 below the cyclone separator 10 and needs to be transported to the second hopper (not shown in the figure), the reversing valve 60 is switched to the discharge passage position. The Roots blower 30 starts, and its outlet generates a high-pressure positive pressure airflow.

[0034] The material exchange pipe 100 connects to the second silo. Positive pressure airflow passes through positive pressure pipe 80, exhaust three-way valve 110, and the second silencing chamber before entering the acceleration chamber 50. Simultaneously, the airlock 40 starts rotating, uniformly unloading the grain from above into the acceleration chamber 50. Inside the acceleration chamber 50, the high-speed airflow thoroughly mixes and accelerates the material particles, forming a stable concentration of gas-solid two-phase flow. This two-phase flow then enters the corresponding reversing valve 60 (switched to the position connected to the material exchange pipe 100), and is finally transported to the distant second silo via the material exchange pipe 100.

[0035] In this mode, the suction pipe 90 is disconnected from the main system path.

[0036] The discharge line is as follows: Roots blower 30 → positive pressure pipeline 80 → exhaust three-way valve 110 → second silencer chamber (optional) → acceleration chamber 50 (grain is mixed in here) → reversing valve 60 → material changing pipeline 100 → second silo (target silo).

[0037] It should be noted that the suction pipe 90 and the material exchange pipe 100 can be designed as needed. They can be designed as described above, sharing part of the pipeline through the reversing valve 60; or they can be designed as two completely independent pipes, one dedicated to suction and the other dedicated to discharge, selectively connected to the material source and destination through the reversing valve 60, to achieve longer-distance and more flexible material handling.

[0038] Preferably, the pulse-type cyclone separator 10 contains a dustproof bag to prevent dust from entering the Roots blower 30; a pulse back-blowing device can be installed on the pulse-type cyclone separator 10, which can back-blow high-pressure air during or after conveying to blow off the dust on the bag and discharge it through the airlock 40.

[0039] Example 2 To address the potential grain clumping problem within the cyclone separator 10 in Example 1, this example improves the structure of the cyclone separator 10.

[0040] The cyclone separator 10 itself includes a cylindrical body 11, a tangentially arranged inlet 12, a top outlet 13, and a conical bottom outlet 15. A connector 14 is provided between the outlet 13 and the negative pressure pipe 70. Inside the connector 14, a set of fan blades 21 are rotatably mounted. The rotation center of the fan blades 21 is connected to a coupling 22 via a detachable threaded fastener. The coupling 22 extends downward into the cylindrical body 11 of the cyclone separator 10.

[0041] Preferably, the feed inlet 12 is arranged horizontally or slightly inclined downwards. This design can effectively guide the movement of particles and reduce short-circuit flow.

[0042] During operation, especially in suction mode, a large amount of air flows out from the air outlet 13, driving the fan blades 21 to rotate at high speed. The rotation of the fan blades 21 causes the connecting shaft 22 to rotate as well, and the material-pulling rod fixed on the connecting shaft 22 also moves accordingly, thereby achieving automatic cleaning of the inner wall of the cylinder 11. To ensure the stability of the rotation of the connecting shaft 22, an annular support ring 23 can be fixed in the middle of the cylinder 11 by means of an inclined upward bracket. The inner hole of the support ring 23 is used to provide radial support for the connecting shaft 22.

[0043] Preferably, the top of the support is pointed to reduce the impact force from falling grain.

[0044] The first specific structure of the feeding assembly: In this structure, the feeding rods consist of several (e.g., three) replaceable first feeding rods 241 (with an upward-facing pointed profile). Multiple slots 242 are provided along the length of the connecting shaft 22. Preferably, the slots 242 have a dovetail-shaped cross-section to provide a self-locking force, preventing the first feeding rods 241 from radially disengaging during rotation. The root of the first feeding rod 241 is also machined into a matching dovetail shape. Its body can be made of hard alloy or a metal rod coated with a wear-resistant coating such as ceramic or tungsten carbide, with its end maintaining slight contact or a very small gap with the conical inner wall of the cylinder 11. During installation, the first feeding rod 241 is slid into the slot opening at the bottom of the connecting shaft 22. After installation, a sealing head 26 is threaded onto the bottom of the connecting shaft 22. This sealing head 26 not only prevents the first feeding rod 241 from sliding axially out but also acts as a counterweight to balance rotation.

[0045] When the fan blade 21 drives the connecting shaft 22 to rotate, the three first feeding rods 241 continuously scrape the inner wall of the cylinder 11, and any initially formed attached clumps will be scraped off immediately, preventing them from growing into clumps.

[0046] The second specific structure of the feeding assembly: In this structure, a first abutment block 252 is slidably sleeved on the connecting shaft 22. A second abutment block 253 (conical in shape) is integrally formed or welded to the lower surface of the fixed support ring 23. The contact surface of the second abutment block 253 is designed as an uneven wavy or cam-shaped surface. A strong axial spring is sleeved between the bottom end cap 26 of the connecting shaft 22 and the first abutment block 252. Figure 7 (The text in the middle is in a compressed state).

[0047] The feeding lever (second feeding lever 251) is radially mounted on the first abutment block 252. Preferably, the second feeding lever 251 (with a pointed upper profile) is not rigidly connected, but elastically connected to the first abutment block 252 via a built-in radial spring. This allows the end of the second feeding lever 251 to extend and retract radially under external force, thereby maintaining a certain elastic pressure on the changing inner wall of the cone.

[0048] Preferably, a cover 255 is also fixed on the support ring 23 to cover the second abutment block 253. The smooth and material-guiding outer wall of the cover 255 prevents the grain from falling and impacting and damaging the first abutment block 252 and adjacent components.

[0049] During operation, the connecting shaft 22 rotates, causing the first abutment block 252 to rotate as well. When the first abutment block 252 slides on the wavy surface of the fixed second abutment block 253, it is forced to reciprocate up and down along the axis of the connecting shaft 22, while simultaneously compressing and releasing the axial spring. The connecting shaft 22, under negative pressure, typically rotates at a high speed, and the wavy surface of the second abutment block 253 can be designed with multiple peaks and troughs. Therefore, during each rotation of the connecting shaft 22, the first abutment block 252 completes several up-and-down reciprocating movements. The conversion from this rotational motion to axial linear reciprocating motion causes the second feeding rod 251 mounted on the first abutment block 252 to also generate high-frequency axial vibration. In this way, the end of the second feeding rod 251 is actually performing a spiral scraping motion, superimposed with high-frequency axial vibration. This compound motion means that the end of the feeding rod is not only scraping the cylinder wall on a plane, but also continuously and densely axially striking the cylinder wall while scraping. For some stubborn clumps, simple tangential scraping force may not be sufficient to peel them off or may be too difficult to peel off. However, this superimposed axial impact force can destroy the internal structure of the clumps through high-frequency impact, making them loose and fragmented, and then they can be completely removed by the rotating scraping motion. This combined action makes its ability to break up grain clumps far stronger than that of a single scraping motion.

[0050] The feeding assembly is not necessarily used during the grain separation process. It can also be used when the Roots blower 30 is running idle to avoid the grain accumulated inside the cylinder 11 interfering with the rotating feeding assembly. In this environment, the grain solidified at the bottom of the cylinder 11 can be more easily dispersed.

[0051] Preferably, the length, shape, and flatness of the ends of the first feed bar 241 and the second feed bar 251 can be selected by the designer.

[0052] To enhance the feeding effect, the cross-section of the second feeding rod 251 can be designed as a rhombus, utilizing its sharp corners to enhance cutting and piercing capabilities. In addition, several small feeding blades 254 can be welded and fixed to the rod body of the second feeding rod 251 to agitate and disperse potential clumps near the non-wall surface and inside the grain flow.

[0053] The technical scope of this utility model is not limited to the content described above. Those skilled in the art can make various modifications and variations to the above embodiments without departing from the technical concept of this utility model, and all such modifications and variations should fall within the protection scope of this utility model.

Claims

1. A flexible pneumatic grain conveying system, characterized in that, include: A cyclone separator has an inlet for tangential entry of a gas-solid mixture, an outlet at the top, and a discharge outlet at the bottom. The gas supply device has a negative pressure port and a positive pressure port; An airlock is located below the material inlet and is used to transfer materials in a sealed state. Reversing valve; And the piping system connecting the above components; The piping system includes: A negative pressure pipeline connects the negative pressure port of the gas source device to the air outlet of the cyclone separator. The suction pipe is connected at one end to the inlet of the cyclone separator and at the other end to the reversing valve; The material changing pipe has one end connected to the reversing valve and the other end used to connect to an external silo. The reversing valve has at least two operating states: In the suction state, the reversing valve connects the material exchange pipe to the material suction pipe, so that the material is sucked into the cyclone separator through the negative pressure generated by the air source device via the material exchange pipe, the reversing valve, and the material suction pipe. In the discharge state, the reversing valve connects the material exchange pipeline to the downstream flow path of the airlock. At the same time, high-pressure airflow from the positive pressure port of the air source device is introduced into the downstream of the airlock so that the material discharged through the airlock is blown to the target silo through the reversing valve and the material exchange pipeline.

2. The flexible grain pneumatic conveying system according to claim 1, characterized in that, It also includes an acceleration chamber, which is located between the outlet of the airlock and the reversing valve; in the discharge state, the high-pressure airflow from the positive pressure port of the air source device is introduced into the acceleration chamber, mixes with the material falling from the airlock and accelerates it.

3. The flexible grain pneumatic conveying system according to claim 2, characterized in that, The pipeline system also includes a positive pressure pipeline that connects the positive pressure port of the gas source device to the acceleration chamber, for delivering high-pressure airflow to the acceleration chamber in the discharge state.

4. The flexible grain pneumatic conveying system according to any one of claims 1-3, characterized in that, The cyclone separator is also equipped with a material-removing component, which is used to clean the material adhering to the inner wall of the cyclone separator.

5. The flexible grain pneumatic conveying system according to claim 4, characterized in that, The feeding assembly includes: The fan blades are rotatably disposed in the airflow channel at the outlet of the cyclone separator and are driven to rotate by the airflow flowing through the outlet. The shaft is connected at its upper end to the fan blades and extends downward into the cylinder of the cyclone separator. At least one feed rod is connected to the connecting shaft and scrapes the inner wall of the cylinder as the connecting shaft rotates.

6. The flexible grain pneumatic conveying system according to claim 5, characterized in that, The feeding rod is a first feeding rod that is detachably mounted on the connecting shaft; the connecting shaft has a slot along its axial direction for accommodating the root of the first feeding rod.

7. The flexible grain pneumatic conveying system according to claim 6, characterized in that, The slot has a dovetail-shaped cross-section, and the root of the first feeding rod has a shape that matches the dovetail-shaped cross-section; the bottom end of the connecting shaft is also provided with a sealing head for sealing the slot opening.

8. The flexible grain pneumatic conveying system according to claim 5, characterized in that, The feeding assembly also includes: The first abutting block is slidably sleeved on the connecting shaft along the axial direction, and the material feeding rod is radially installed on the first abutting block; The second abutment block is fixedly disposed inside the cylinder and abuts against the convex surface of the first abutment block. The abutment surface of the second abutment block has a non-planar profile with undulations. An axial spring, sleeved on the connecting shaft, is used to apply axial elastic force to the first abutment block, so that the abutment surfaces of the first abutment block and the second abutment block remain in contact.

9. The flexible grain pneumatic conveying system according to claim 8, characterized in that, The feeding rod is elastically connected to the first abutment block via a radial spring, so that its end can maintain elastic pressure on the inner wall of the cylinder.

10. The flexible grain pneumatic conveying system according to claim 8 or 9, characterized in that, The cross-section of the feeding rod is rhomboid, and the rod body is also provided with a stirring blade for stirring the material.

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