An environmentally friendly negative pressure conveying device for powder tank trucks

Abstract

This invention discloses an environmentally friendly negative pressure conveying device for powder tank trucks, relating to the field of conveying technology. It includes a double-layer unloading gate valve, a transition chute, and a feeding terminal, sequentially and sealed along the material flow direction at the outlet of the storage silo. The feeding terminal is axially slidingly fitted onto the outside of the transition chute and driven by a lifting device to perform vertical displacement along the axis of the transition chute. This invention constructs a leak-free conveying link through a fully sealed design. The double-layer unloading gate valve blocks dust diffusion at the source. The three-layer flow channel of the composite feeding component, combined with an annular jet duct and airflow guide ring, constructs a stable directional negative pressure adsorption field. Compared to traditional simple negative pressure technology, the negative pressure intensity and airflow velocity are significantly improved, thoroughly capturing dust near the tank truck inlet, achieving zero dust escape. Simultaneously, the peripheral dust extraction duct tightly conveys the captured dust to the treatment equipment, fundamentally solving the problem of unloading dust pollution and improving the working environment.

Description

Technical Field

[0001] This invention relates to the field of conveying technology, specifically to an environmentally friendly negative pressure conveying device for powder tank trucks. Background Technology

[0002] In the unloading of powdered materials such as lime from tank trucks, traditional conveying devices generally have many technical pain points, which seriously affect the environmental protection, stability and efficiency of the operation.

[0003] First, dust pollution during the unloading process is a prominent issue: when tank trucks are loaded with ash, dust is easily scattered outwards from multiple feed holes, and there is a height difference between the discharge chute and the tank truck feed inlet, making it easy for powder to spill outside the tank. At the same time, traditional dust collection technology is mostly based on simple negative pressure adsorption, which is affected by insufficient sealing and airflow turbulence, resulting in insufficient negative pressure strength and difficulty in completely capturing dust, causing deterioration of the working environment and waste of materials.

[0004] Secondly, the unloading stability is poor: the single valve structure is difficult to meet the high pressure bearing and sealing and leakage prevention requirements of the storage silo. Large particles mixed in the material can easily block the valve plate, causing ash leakage or failure to close. In addition, improper valve assembly connection can easily cause action interference. An unreasonable opening and closing sequence can also cause material retention.

[0005] Furthermore, the reliability of material level monitoring is insufficient: conventional sensors are easily affected by dust adhesion, leading to distorted detection signals and monitoring lag, often resulting in excessively high material levels causing overflow or material residue. In addition, traditional devices lack self-cleaning functions, and the inner walls of the dust extraction ducts are prone to dust accumulation and blockage, requiring frequent manual cleaning. This not only increases maintenance workload and costs but may also lead to a decrease in negative pressure efficiency and a shortened equipment lifespan due to untimely cleaning. Simultaneously, the device has poor adaptability, requiring the replacement of compatible parts for tank trucks of different heights, limiting operational flexibility. These problems collectively restrict the environmentally friendly, automated, and efficient development of powder material unloading operations, urgently requiring a new type of conveying device that integrates closed conveying, efficient dust removal, accurate monitoring, and automatic maintenance. Summary of the Invention

[0006] The purpose of this invention is to provide an environmentally friendly negative pressure conveying device for powder tank trucks, so as to solve the problems mentioned in the background art.

[0007] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0008] The present invention provides an environmentally friendly negative pressure conveying device for powder tank trucks, comprising a double-layer unloading gate valve, a transition chute, and a feeding terminal that are sequentially and sealed to the outlet of the storage silo along the material flow direction; the feeding terminal is fitted onto the outside of the transition chute in an axial sliding fit manner and is driven by a lifting device to make vertical displacement along the axis of the transition chute.

[0009] The feeding terminal includes a composite feeding component, a material level monitoring component, and a self-cleaning dust collection component. The composite feeding component adopts a multi-layer sleeve structure, which includes a central material conveying channel, an annular jet air duct, and an outer peripheral dust extraction air duct arranged sequentially from the inside out. The air inlet of the annular jet air duct is sealed through a flexible air supply pipe, and the dust outlet of the outer peripheral dust extraction air duct is connected to a negative pressure dust extraction hose. An airflow guide ring is fixedly provided in the air outlet section of the annular jet air duct, and the outflow direction of the airflow guide ring points to the air inlet area of ​​the outer peripheral dust extraction air duct, thereby constructing a directional negative pressure adsorption field.

[0010] The material level monitoring component includes a material probe, a low-pressure air supply module, and a differential pressure controller. The material probe is installed on the composite feeding component, and the detection end of the material probe extends to the bottom of the feeding component and is lower than the outlet plane of the central material conveying channel. The output end of the low-pressure air supply module is connected to the air inlet of the material probe and the sensing interface of the differential pressure controller through a three-way conversion connector.

[0011] The self-cleaning dust collection assembly includes scrapers evenly distributed along the inner circumference of the outer periphery of the dust extraction duct, a pneumatic rotary drive unit installed at the end of the dust extraction duct, and a connecting rod connecting the scrapers and the pneumatic rotary drive unit.

[0012] Furthermore, the double-layer unloading gate valve includes a main valve and a secondary valve. The main valve is a metal hard-seal pneumatic stacked valve driven by a cylinder, and the secondary valve is a pneumatic powder stacked valve. The main valve and the secondary valve are connected by a connecting joint and the valve plate moves without interference. When opening the valve, the secondary valve is opened first and then the main valve is opened. When closing the valve, the main valve is closed first and then the secondary valve is closed after a delay.

[0013] Furthermore, the lifting device includes a wire rope, a pulley system, and a cylinder. There are three wire ropes, which are evenly distributed around the feeding terminal. The pulley system includes a horizontal pulley, a vertical guide pulley, and a three-groove pulley. One end of the three wire ropes is fixedly connected to the feeding terminal, and the other end of the three wire ropes is connected to the output end of the cylinder after being turned by the pulley system.

[0014] Furthermore, the feeding terminal is equipped with a trigger rod, and the transition chute is equipped with an induction switch for detecting the position of the trigger rod. When the feeding terminal descends, the trigger rod moves away from the induction switch, and the electrical control component activates an audible and visual alarm; when the lifting section rises, the trigger rod approaches the induction switch, and the alarm stops.

[0015] Furthermore, the detection end of the probe tube is equipped with an anti-stick cap. The anti-stick cap includes a connecting cylinder threaded inside the detection end and a dust baffle plate set on the top of the connecting cylinder. The dust baffle plate is uniformly provided with spiral grooves along the circumferential direction. The air inlet and outlet of the spiral grooves are staggered, and the cross-section of the spiral grooves decreases continuously along the gas flow direction.

[0016] Furthermore, the composite feeding assembly includes an inner cylinder, an annular sealing plate, a middle cylinder, and an outer cylinder. The inner cylinder is slidably assembled to the outer wall of the transition chute via an adapter seal. The annular sealing plate is fixedly connected to the outer wall of the inner cylinder. The middle cylinder and the outer cylinder are coaxially fixedly welded to the bottom of the annular sealing plate. A central material conveying channel is formed inside the inner cylinder. An annular jet air duct with an annular opening at the bottom is formed between the inner cylinder and the middle cylinder. An outer dust extraction air duct with an annular opening at the bottom is formed between the middle cylinder and the outer cylinder. An outwardly expanding flared mouth is integrally formed at the bottom of the outer cylinder. A first connector penetrating the outer cylinder is welded to the side wall of the middle cylinder. A second connector is welded to the side wall of the outer cylinder. The bottom plane of the inner cylinder is lower than the bottom plane of the outer cylinder, and the bottom plane of the outer cylinder is lower than the bottom plane of the middle cylinder.

[0017] Furthermore, the airflow guide ring is fixedly installed on the outer wall of the inner cylinder below the middle cylinder by welding or bolting, and the installation position of the airflow guide ring corresponds to the bottom outlet of the annular jet air duct and the inlet of the outer peripheral dust extraction air duct. The top of the airflow guide ring is integrally formed with a smooth transition annular arc surface, and the side of the airflow guide ring extends vertically upward to form a side ring. The side ring is located inside the outer peripheral dust extraction air duct between the middle cylinder and the outer cylinder.

[0018] Furthermore, the pneumatic rotary drive includes a pair of parallel rotating rings, with multiple spiral blades uniformly welded between the pair of rotating rings along the circumferential direction, and the pair of rotating rings are mounted on the inner wall of the middle cylinder via a thrust bearing.

[0019] Furthermore, a through groove is formed at the center of the scraper along its length, the working blade of the scraper is specially treated for wear resistance, and the scraper maintains a constant contact pressure with the inner wall of the outer dust extraction duct.

[0020] Compared with existing technologies, one or more of the above technical solutions have the following beneficial effects:

[0021] 1. This invention constructs a leak-free conveying link through a fully enclosed design. The double-layer unloading gate valve blocks dust diffusion at the source. The three-layer flow channel of the composite feeding component, together with the annular jet air duct and airflow guide ring, constructs a stable directional negative pressure adsorption field. Compared with traditional simple negative pressure technology, the negative pressure intensity and airflow velocity are greatly improved, which can completely capture dust near the tank truck inlet and achieve zero dust escape. At the same time, the peripheral dust extraction air duct transports the captured dust to the treatment equipment in a sealed manner, fundamentally solving the problem of unloading dust pollution and improving the working environment.

[0022] 2. The double-layer unloading gate valve of this invention adopts a main and auxiliary valve collaborative structure and scientific switching logic, which not only meets the high pressure bearing requirements, but also avoids large particle blockage and material residue, ensuring a sealing and leak-proof effect; the lifting device uses three evenly distributed steel wire ropes and multiple sets of pulleys to achieve stable lifting and lowering of the feeding terminal, accurately connecting with tank trucks of different heights, eliminating material spillage and conveying obstruction caused by height differences; the material level monitoring component avoids dust interference through low-pressure airflow purging and anti-stick cap design, and the material probe detects material level changes in advance, which, together with the differential pressure controller, quickly feeds back signals, effectively avoiding overflow and residue, and ensuring continuous conveying.

[0023] 3. The self-cleaning dust collection component of this invention utilizes the airflow of the annular jet duct to drive a pneumatic rotating drive component, which in turn drives a scraper to automatically clean the dust accumulated on the inner wall of the outer peripheral dust extraction duct. The strip-shaped groove in the center of the scraper further enhances the dust removal effect and rotational flexibility. No additional power source is required, which greatly reduces the frequency of manual cleaning. At the same time, the structural design of each component is adapted to the powder conveying characteristics, and the wear-resistant materials and scientific connection methods extend the service life of the equipment and reduce component wear and maintenance costs.

[0024] 4. The feeding terminal of this invention, through axial sliding and lifting device, can meet the unloading needs of receiving equipment of different heights without the need to replace the adapter parts, significantly expanding the operational flexibility and application scope; the device adopts the "one-click ash discharge" automated control logic, combined with audible and visual alarms, valve group coordination, material level linkage and other functions, reducing manual operation intervention, reducing the risk of misoperation, and improving operation efficiency and safety.

[0025] 5. The spiral blades of the pneumatic rotary drive component of this invention have both power receiving and rectification functions, enabling the airflow to form a uniform annular airflow, further improving the stability of the negative pressure adsorption field; the spiral groove and spacing design of the anti-adhesion cap provides multi-dimensional protection from blocking dust intrusion, peeling off dust accumulated on the inner wall, and avoiding surface adhesion, ensuring the reliability of the monitoring components. The coordinated cooperation of various structures achieves functional integration, reducing energy consumption and improving the overall performance of the device while simplifying the overall structure.

[0026] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description

[0027] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0028] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0029] Figure 2 This is a schematic diagram of the feeding terminal structure of the present invention;

[0030] Figure 3 This is a cross-sectional view of the feeding terminal structure of the present invention;

[0031] Figure 4 yes Figure 2 A schematic diagram of the structure after the outer and inner cylinders are hidden;

[0032] Figure 5 This is a first-view structural schematic diagram of the anti-stick cap of the present invention;

[0033] Figure 6 This is a second-view structural schematic diagram of the anti-stick cap of the present invention;

[0034] Figure 7 This is a perspective structural diagram of the anti-stick cap of the present invention.

[0035] In the picture:

[0036] 1-Storage bin; 2-Double-layer discharge gate valve; 21-Main valve; 22-Auxiliary valve; 3-Transition chute; 4-Feeding terminal; 41-Composite feeding assembly; 411-Central conveying channel; 412-Annular jet duct; 413-Outer peripheral dust extraction duct; 414-Airflow guide ring; 4141-Annular arc surface; 4142-Side ring; 415-Inner cylinder; 416-Annular sealing plate; 417-Middle cylinder; 418-Outer cylinder; 42-Material level monitoring assembly; 421- 422-Low-pressure air supply module; 423-Differential pressure controller; 43-Self-cleaning dust collection assembly; 431-Scraper; 4311-Through groove; 432-Pneumatic rotary drive component; 4321-Rotating ring; 4322-Spiral blade; 433-Connecting rod; 5-Lifting device; 51-Wire rope; 52-Pulley block; 53-Cylinder; 6-Trigger rod; 61-Inductive switch; 7-Anti-stick cap; 71-Connecting cylinder; 72-Dust baffle; 73-Spiral through groove. Detailed Implementation

[0037] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0038] Please see Figures 1-7 The present invention provides an environmentally friendly negative pressure conveying device for powder tank trucks, including a double-layer unloading gate valve 2, a transition chute 3 and a feeding terminal 4 that are sequentially and sealed to the outlet of the storage silo 1 along the material flow direction. The components are connected in a sealed manner to form a complete closed conveying line, ensuring that there is no leakage and no dust escape during the entire material conveying process.

[0039] Among them, the double-layer unloading gate valve 2 adopts a multi-layer sealing structure design. Its structural design fully considers the pressure fluctuation characteristics during the material conveying process. Through the adaptive adjustment of the layer-by-layer sealing structure, the outlet of the storage bin 1 and the transition chute 3 are tightly fitted, cutting off the dust diffusion path from the source of material conveying.

[0040] The transition chute 3 serves as the connecting carrier between the double-layer unloading gate valve 2 and the feeding terminal 4. Its internal channel adopts a regular design to provide a stable and smooth conveying channel for materials.

[0041] The feeding terminal 4 is axially slidably fitted onto the outside of the transition chute 3 and is driven by a lifting device 5 to move vertically along the axis of the transition chute 3. The lifting device 5's driving function allows for flexible adjustment of the vertical position of the feeding terminal 4 according to the actual feeding height of the receiving equipment, ensuring precise alignment between the feeding terminal 4's discharge end and the receiving equipment's inlet, eliminating gaps caused by height deviations during traditional unloading processes. Simultaneously, it meets the unloading needs of receiving equipment at different heights, significantly improving the device's operational flexibility and applicability, and effectively preventing material splashing or conveying obstruction caused by alignment deviations.

[0042] The feeding terminal 4 includes a composite feeding component 41, a material level monitoring component 42, and a self-cleaning dust collection component 43. The three components respectively undertake the functions of material conveying, material level monitoring, and dust cleaning.

[0043] The composite feeding assembly 41 adopts a multi-layer sleeve structure, which includes an independent central material conveying channel 411, an annular jet air channel 412, and an outer peripheral dust extraction air channel 413 formed sequentially from the inside to the outside, with the three channels cooperating with each other. The central material conveying channel 411 provides a dedicated conveying channel for materials, allowing materials and airflow to run separately, avoiding mutual interference between materials and airflow, and ensuring the smoothness and stability of material flow. The dust outlet of the peripheral dust extraction channel 413 is sealed to the negative pressure dust extraction hose, forming a complete closed dust collection path, so that all dust captured by the negative pressure field can be transported to the designated treatment equipment. The air inlet of the annular jet channel 412 is sealed to the air supply equipment through a flexible air supply pipeline. The air supply equipment can supply high-pressure gas to the annular jet channel 412. When the high-pressure gas is discharged from its air outlet, the airflow guide ring 414 fixedly set in its air outlet section is designed with a targeted structure to guide the airflow to the area around the air inlet of the peripheral dust extraction channel 413. Through the directional impact and diversion effect of the airflow, a stable directional negative pressure adsorption field is built at the air inlet (dust extraction port) of the peripheral dust extraction channel 413. Compared to traditional negative pressure vacuuming technology, this design enhances the airflow velocity at the vacuum port through airflow guidance. This reduces the risk of clogging caused by powder adhering to the inner wall of the vacuum port and further enhances the negative pressure intensity of the vacuum port. It effectively solves the problem of insufficient negative pressure caused by factors such as insufficient sealing and unreasonable conveying path in traditional vacuuming technology, and significantly improves the environmental performance of the working environment.

[0044] The material level monitoring component 42 includes a probe tube 421, a low-pressure air supply module 422, and a differential pressure controller 423, which are connected by a sealed pipeline to form a complete monitoring system. Compared with conventional technologies where sensors are easily affected by dust adhesion, leading to distorted detection signals, reduced monitoring accuracy, or even functional failure, the material level monitoring component 42 of this invention, through the stable airflow continuously delivered by the low-pressure air supply module 422, can blow away dust at the detection end and surrounding area of ​​the probe tube 421 in real time, preventing dust adhesion and accumulation from interfering with detection. This structural design avoids the adverse effects of dust on monitoring.

[0045] Specifically, the probe 421 is installed on the composite feeding assembly 41, with its detection end extending to the bottom of the feeding assembly and below the outlet plane of the central conveying channel 411. This installation design allows the probe 421 to detect changes in the material level within the receiving equipment in advance, further avoiding monitoring failures caused by delayed detection or dust interference. The output end of the low-pressure air supply module 422 is sealed and connected to the air inlet of the probe 421 and the sensing interface of the differential pressure controller 423 via a three-way adapter, ensuring both the stability of airflow transmission and the accurate transmission of differential pressure signals, while also maintaining the cleanliness of the detection end of the probe 421 through continuous airflow. During operation, the low-pressure air supply module 422 continuously supplies a stable airflow to the probe 421. When the detection end of the probe 421 comes into contact with the material, the airflow is obstructed, causing a change in the differential pressure within the pipe. The differential pressure controller 423 can capture this differential pressure change signal in real time and provide rapid feedback, achieving accurate real-time monitoring of the material level. Operators can adjust the conveying rhythm in a timely manner based on feedback signals, effectively avoiding overflow pollution caused by excessively high material levels, while preventing material residue caused by lagging material level monitoring or dust interference, thus ensuring the stability and continuity of the conveying process.

[0046] The self-cleaning dust collection assembly 43 includes scraper blades 431 evenly distributed along the inner circumference of the outer periphery of the dust extraction duct 413, a pneumatic rotary drive component 432 installed in the annular jet duct 412, and a connecting rod 433 connecting the scraper blades 431 and the pneumatic rotary drive component 432. These three components form a collaborative dust removal structure. The working edge of the wear-resistant scraper blades 431 is specially treated to maintain a constant contact pressure with the inner wall of the dust extraction duct. This design ensures effective dust removal from the inner wall of the duct while preventing damage to the inner wall from the scraper blades 431. During operation, the airflow delivered by the annular jet duct 412 directly drives the pneumatic rotary drive component 432 to rotate without an additional power source. The connecting rod 433 drives the wear-resistant scraper blades 431 to rotate at a uniform speed along the inner wall of the duct, continuously removing dust adhering to the inner wall of the duct. This design effectively prevents dust accumulation from causing a reduction in the cross-sectional area of ​​the air duct, a decrease in negative pressure adsorption efficiency, or even air duct blockage, ensuring the long-term efficient and stable operation of the negative pressure adsorption system. Simultaneously, the automatic dust scraping design significantly reduces the frequency of manual cleaning, lowering the workload for operators and equipment maintenance costs. It also avoids potential damage to the equipment caused by untimely or incomplete manual cleaning, effectively extending the overall service life of the device.

[0047] In this embodiment, the double-layer unloading gate valve 2 includes a main valve 21 and a secondary valve 22. The main valve 21 is a metal hard-seal pneumatic stacked valve driven by a cylinder 53. The metal hard-seal material can withstand the large pressure generated by the material in the storage silo 1. The cylinder 53 is stably connected to the valve shaft through a swing arm, which can realize precise pneumatic control of the valve plate and meet the driving requirements of automated operation. The secondary valve 22 is a pneumatic powder stacked valve. Its structure is adapted to the conveying characteristics of powdery materials and can effectively deal with large particle impurities mixed in the material, avoiding impurities from clogging the valve plate and affecting the sealing effect. The main valve 21 and the secondary valve 22 are sealed and connected by a special connecting joint, which reserves independent opening and closing actions for the two valve plates. Ample operating space ensures that the valve plates of the main valve 21 and the auxiliary valve 22 do not interfere with each other during operation, guaranteeing smooth opening and closing. During operation, the system follows the control logic of "opening the auxiliary valve 22 first, then the main valve 21; closing the main valve 21 first, then delaying the closure of the auxiliary valve 22." Opening the auxiliary valve 22 first during valve opening establishes a material flow channel in advance, preventing direct damage to the auxiliary valve 22 valve plate from high-pressure impact when the main valve 21 opens. It also reduces the impact of pressure buildup on the sealing structure. Closing the main valve 21 first during valve closing quickly cuts off the main material flow, while delaying the closure of the auxiliary valve 22 allows residual material trapped between the main valve 21 and the auxiliary valve 22 to be discharged smoothly, preventing material clumping, blockage, or leakage.

[0048] In this embodiment, the lifting device 5 includes a wire rope 51, a pulley block 52, and a cylinder 53. There are three wire ropes 51, evenly distributed around the feeding terminal 4. The pulley block 52 includes a horizontal pulley, a vertical guide pulley, and a three-groove pulley. The horizontal pulley is mounted on the hanging plate of the feeding terminal 4 to change the tension direction of the wire rope 51 from vertical to horizontal, reducing lateral forces on the feeding terminal 4 itself. The vertical guide pulley is installed vertically to precisely guide the vertical movement of the wire rope 51, preventing... To prevent the steel wire rope 51 from swaying and deviating from the preset path, a three-groove pulley is horizontally set, with each of its three grooves corresponding to one of the three steel wire ropes 51. This allows the dispersed steel wire ropes 51 to be guided to the output end of the cylinder 53, ensuring the synchronous movement of the three steel wire ropes 51. Specifically, one end of each of the three steel wire ropes 51 is securely connected to a fixed point around the perimeter of the feeding terminal 4. The other ends of the three steel wire ropes 51 sequentially pass around the horizontal pulley to change their horizontal direction, are corrected for their vertical trajectory by the vertical guide pulley, and then undergo a concentrated turning motion through the three-groove pulley before being connected to the output end of the cylinder 53. During operation, the cylinder 53 extends and retracts, causing the three steel wire ropes 51 to move in and out synchronously. Under the guidance and positioning of the pulley group 52, the feeding terminal 4 smoothly rises and falls along the axis of the transition chute 3.

[0049] In this embodiment, the feeding terminal 4 is equipped with a trigger rod 6. The length and installation height of the trigger rod 6 are adapted to ensure that the inductive switch 61 can accurately capture its position change. Along the lifting trajectory of the feeding terminal 4, the transition chute 3 is fixedly installed with an inductive switch 61 with adapted sensitivity. The inductive switch 61 and the electrical control components establish a stable signal connection through the line to ensure the timeliness and accuracy of position signal transmission. During operation, when the feeding terminal 4 descends along the transition chute 3 under the drive of the lifting device 5 to approach the tank truck inlet, the trigger rod 6 fixed on the feeding terminal 4 moves down accordingly, gradually moving away from the induction switch 61 on the transition chute 3. After the induction switch 61 no longer detects the signal from the trigger rod 6, it immediately sends a trigger command to the electrical control component. The electrical control component activates the audible and visual alarm device, using clear audible and visual signals to remind the driver that the equipment is in the unloading operation state and prohibits moving the vehicle. When unloading is completed, as the feeding terminal 4 rises back up along the transition chute 3 under the drive of the lifting device 5, the trigger rod 6 moves up accordingly, gradually approaching the induction switch 61. After the induction switch 61 detects the signal from the trigger rod 6, it sends a reset command back to the electrical control component, the audible and visual alarm device stops working, and the driver is notified that the operation is complete and the vehicle can be moved.

[0050] In this embodiment, an anti-adhesion cap 7 is installed at the detection end of the probe tube 421. This anti-adhesion cap 7 features a refined structural design to meet monitoring requirements in dusty environments. Specifically, it includes a connecting cylinder 71 tightly connected to the inside of the detection end of the probe tube 421 via threads, and a dust baffle 72 integrally formed on the top of the connecting cylinder 71. A reasonable gap is reserved between the dust baffle 72 and the plane of the detection end of the probe tube 421, providing ample space for airflow while preventing powder from adhering to the surface of the dust baffle 72 when the tube is full. Multiple spiral grooves 73 are evenly distributed along the circumference of the dust baffle 72. The air inlets and outlets of each spiral groove 73 are staggered, and the cross-section of each spiral groove 73 gradually decreases along the gas flow direction. This design ensures the continuity of the airflow channel and guides the airflow to form a specific flow state.

[0051] During operation, the stable airflow delivered by the low-pressure air supply module 422 enters the connecting cylinder 71 through the internal channel of the probe tube 421. Under the precise guidance of the spiral groove 73, it forms a strong swirling flow. On the one hand, the swirling airflow forms a continuous and uniform scouring force along the inner wall of the connecting cylinder 71. This scouring force can fully cover all areas of the inner wall of the connecting cylinder 71, effectively stripping dust particles that have been attached to the cylinder wall, preventing dust from accumulating on the cylinder wall and causing the channel cross-sectional area to shrink or even become blocked, thus ensuring smooth airflow. On the other hand, the centrifugal force generated by the swirling airflow during its flow can throw dust particles that attempt to enter the connecting cylinder 71 from the outside outwards, forming a protective barrier and preventing external dust from intruding into the ventilation area of ​​the probe tube 421. Meanwhile, the staggered design of the air inlet and outlet of the spiral channel 73 structurally cuts off the path for the powder to enter in reverse, while the gradually decreasing cross-section design allows the airflow velocity to gradually increase when passing through the channel 4311, further enhancing the scouring force and centrifugal force of the vortex, making the anti-sticking and anti-clogging function of the airflow more significant, and further improving the adaptability and monitoring accuracy of the material level monitoring component 42 in dusty environments.

[0052] In this embodiment, the composite feeding assembly 41 includes an inner cylinder 415, an annular sealing plate 416, a middle cylinder 417, and an outer cylinder 418. The inner cylinder 415 is slidably assembled to the outer wall of the transition chute 3 via an adapter seal. The annular sealing plate 416 is fixedly connected to the outer wall of the inner cylinder 415 by a full welding process. The middle cylinder 417 and the outer cylinder 418 are fixedly welded to the bottom of the annular sealing plate 416 by a coaxial positioning structure. The middle cylinder 417 is located outside the inner cylinder 415 and maintains a distance from the inner cylinder 415. With uniform spacing, the outer cylinder 418 is fitted outside the middle cylinder 417 and maintains the same uniform spacing as the middle cylinder 417, thereby forming a dedicated central material conveying channel 411 inside the inner cylinder 415. The inner cylinder 415 and the middle cylinder 417 enclose each other to form an annular jet air duct 412 with an annular opening at the bottom, and the middle cylinder 417 and the outer cylinder 418 enclose each other to form an outer peripheral dust extraction air duct 413 with an annular opening at the bottom. The bottom of the outer cylinder 418 is integrally formed with an outwardly expanding flared mouth, which can expand the dust collection coverage. To improve dust capture efficiency, the inner cylinder 417 has a first connector welded to its side wall, penetrating the outer cylinder 418. This first connector is used for a sealed connection with the flexible air delivery pipeline, supplying airflow to the annular jet duct 412. The outer cylinder 418 has a second connector welded to its side wall, which is used for a sealed connection with the negative pressure suction hose, discharging the captured dust. Simultaneously, the bottom plane of the inner cylinder 415 is lower than the bottom plane of the outer cylinder 418, and the bottom plane of the outer cylinder 418 is lower than the bottom plane of the inner cylinder 417. This stepped height... The design allows the discharge end of the central conveying channel 411 to extend deep into the tank truck, reducing dust diffusion during material transport. At the same time, it ensures that the air outlet of the annular jet duct 412 and the dust suction port of the peripheral dust extraction duct 413 are positioned in a reasonable correspondence. During operation, the central conveying channel 411 is dedicated to transporting powder materials, and the airflow transported by the annular jet duct 412 can be precisely guided to the dust suction port of the peripheral dust extraction duct 413. The peripheral dust extraction duct 413 captures dust through negative pressure, significantly improving the environmental friendliness and stability of the transport process.

[0053] In this embodiment, the airflow guide ring 414 is fixedly installed on the outer wall of the inner cylinder 415 below the middle cylinder 417 by welding or bolting. Its installation position precisely corresponds to the bottom outlet of the annular jet air duct 412 and the inlet of the outer peripheral dust extraction air duct 413. The top of the airflow guide ring 414 has a smoothly transitioned annular arc surface 4141 integrally formed. This arc surface can reduce the resistance during airflow impact and avoid airflow turbulence. At the same time, the side of the airflow guide ring 414 extends vertically upward to form a circle. Side ring 4142 is located inside the outer peripheral dust extraction duct 413 between the middle cylinder 417 and the outer cylinder 418. When working, the airflow delivered by the annular jet duct 412 flows downward and first contacts the annular arc surface 4141 of the airflow guide ring 414. Under the guidance of the arc surface, it diffuses outward and then flows precisely to the air inlet of the outer peripheral dust extraction duct 413 under the limiting effect of the side ring 4142. A stable directional negative pressure adsorption field is constructed through the directional impact and diversion effect of the airflow.

[0054] In this embodiment, the pneumatic rotary drive component 432 adopts an airflow drive structure without an additional power source. Specifically, it includes a pair of parallel rotating rings 4321. The rotating rings 4321 are made of lightweight and wear-resistant metal to reduce airflow driving resistance. Multiple spiral blades 4322 are uniformly welded between the pair of rotating rings 4321 along the circumferential direction. The tilt angle and curvature of the spiral blades 4322 are calculated to maximize the reception of airflow thrust and to rectify the flow, so that the flowing airflow forms a uniform annular airflow before being discharged. The width of the rotating rings 4321 is slightly smaller than the width of the annular jet duct 412 to ensure that the rotating rings 4321 and the spiral blades 4322 can be completely accommodated within the annular jet duct 412 without affecting the normal flow of airflow. At the same time, the pair of rotating rings 4321 are mounted on a thrust bearing. The inner wall of the middle cylinder 417 allows the rotating ring 4321 to rotate flexibly around the middle cylinder 417. During operation, when the airflow in the annular jet duct 412 flows through the spiral blade 4322, it will generate a continuous thrust on the spiral blade 4322, driving the pair of rotating rings 4321 and the spiral blade 4322 to rotate around the middle cylinder 417 as a whole. At the same time, the uniform annular airflow after being rectified by the spiral blade 4322 can more accurately cooperate with the airflow guide ring to act on the air inlet of the outer peripheral dust extraction duct 413, further improving the stability and uniformity of the directional negative pressure adsorption field. There is no need to configure additional power devices such as motors, which simplifies the structure, reduces energy consumption, and provides power to the scraper of the self-cleaning dust collection component 43 through stable rotational motion, ensuring that the scraper rotates at a uniform speed to scrape dust, ensuring the cleanliness of the inner wall of the outer peripheral dust extraction duct 413, and avoiding dust accumulation that affects the dust collection effect.

[0055] In this embodiment, a strip-shaped through groove 4311 is formed at the center of the scraper 431 along its length. The width and length of the strip-shaped through groove 4311 are designed to fit the overall structural strength of the scraper 431 without affecting it, while providing a channel for airflow. The working edge of the scraper 431 is specially treated for wear resistance, maintaining a constant contact pressure with the inner wall of the outer dust extraction duct 413 to ensure the dust removal effect. During operation, the scraper 431 rotates at a constant speed along the inner wall of the duct under the drive of the pneumatic rotary drive 432, scraping away the attached dust. At the same time, the annular jet duct 4... 12. Part of the airflow in the outer peripheral dust extraction duct 413 passes through the strip groove 4311 in the center of the scraper 431. On the one hand, this reduces the airflow resistance encountered by the scraper 431 when it rotates, making the scraper 431 rotate more smoothly and reducing the load on the drive components. On the other hand, when the airflow passes through the groove 4311, it will blow on both sides of the scraper 431, effectively removing the dust attached to the surface of the scraper 431, preventing the scraper 431 from becoming dusty and reducing its dust removal effect. At the same time, the groove 4311 can also allow some airflow to reach the scraping area on the inner wall of the duct, assisting in the removal of stubborn dust.

[0056] This device achieves environmentally friendly and efficient unloading of powdered lime through a closed conveying system, negative pressure dust collection, precise monitoring, and automatic cleaning. The overall workflow revolves around the logic of positioning, early warning, unloading, monitoring, cleaning, and resetting. Specifically:

[0057] After the tanker truck arrives at the designated unloading position, the operator initiates the "one-button ash release" command, triggering the lifting device 5 via the electrical control components. The cylinder 53 of the lifting device 5 extends and retracts, simultaneously raising and lowering three evenly distributed steel wire ropes 51. Guided and steered by horizontal pulleys, vertical guide pulleys, and a three-groove pulley, the steel wire ropes 51 pull the feeding terminal 4 smoothly downwards along the axis of the transition chute 3. During this process, the trigger rod 6 on the feeding terminal 4 moves downwards and away from the induction switch 61 on the transition chute 3. The induction switch 61 immediately sends a signal to the electrical control components, activating an audible and visual alarm to remind the driver not to move the vehicle, ensuring operational safety.

[0058] When the feeding terminal 4 descends to the discharge end and precisely connects with the tank truck inlet, the electrical control component controls the double-layer unloading gate valve 2 to operate according to the preset logic: first, the auxiliary valve 22 (pneumatic powder stack valve) is opened to establish a material flow channel in advance, avoiding damage to the valve plate by the high-pressure material impact when the main valve 21 is opened; then, the main valve 21 (metal hard-seal pneumatic stack valve driven by cylinder 53) is opened, and the powdered lime in the storage bin 1 enters the transition chute 3 through the main valve 21 and the auxiliary valve 22, and is then transported to the inside of the tank truck through the central conveying channel 411 of the composite feeding component 41. The composite feeding assembly 41 adopts a three-layer sleeve structure of inner cylinder 415, middle cylinder 417, and outer cylinder 418. The bottom plane of the inner cylinder 415 is lower than that of the outer cylinder 418 and the middle cylinder 417, so that the discharge end of the conveying channel extends deep into the tank truck, reducing dust diffusion from the source. At the same time, the air supply equipment is connected to the first joint of the middle cylinder 417 through a flexible air supply pipeline, and delivers high-pressure gas to the annular jet air duct 412. The gas is guided by the annular arc surface 4141 of the airflow guide ring 414 and limited by the side ring 4142, and flows to the area around the air inlet of the outer peripheral dust extraction air duct 413, creating a stable directional negative pressure adsorption field. Dust generated near the tank truck inlet is instantly captured and transported to the designated treatment equipment through the negative pressure dust extraction hose connected to the outer peripheral dust extraction air duct 413 and the second joint, achieving zero dust escape.

[0059] During unloading, the material level monitoring component 42 operates continuously. The low-pressure air supply module 422 continuously supplies a stable airflow to the material detection pipe 421 through a three-way conversion connector. After the airflow enters the anti-stick cap 7 at the detection end of the material detection pipe 421, it forms a swirling flow under the guidance of the spiral groove 73. This swirling flow not only washes away the accumulated dust on the inner wall of the connecting cylinder 71, but also prevents external dust from intruding through centrifugal force, ensuring unobstructed ventilation. The detection end of the material detection pipe 421 is lower than the outlet of the central conveying channel 411, allowing it to detect changes in the material level inside the tanker truck in advance. When material comes into contact with the detection end of the material detection pipe 421, the airflow is obstructed, causing a change in the pressure difference inside the pipe. The pressure difference controller 423 captures this signal in real time and feeds it back to the electrical control component, issuing a full-material warning in a timely manner.

[0060] Simultaneously, the self-cleaning dust collection component 43 operates synchronously. When the high-pressure airflow in the annular jet duct 412 flows through the spiral blades 4322 of the pneumatic rotary drive component 432, it generates a continuous thrust that drives the rotating ring 4321 to rotate around the central cylinder 417. The rotating ring 4321, through the connecting rod 433, pulls the scraper blade 431 to rotate uniformly along the inner wall of the outer peripheral dust extraction duct 413. The strip-shaped through groove 4311 in the center of the scraper blade 431 reduces airflow resistance and allows the airflow to sweep the surface of the scraper blade 431 and the inner wall of the duct, assisting in the removal of stubborn dust and preventing the duct cross-sectional area from shrinking or becoming blocked, thus affecting the dust collection effect.

[0061] Upon receiving the full material signal, the electrical control component first closes the main valve 21, quickly cutting off the main material flow; after a 4-second delay, it closes the auxiliary valve 22 to ensure that any residual material between the main valve 21 and the auxiliary valve 22 is completely discharged, preventing clumping, blockage, or leakage. Subsequently, the cylinder 53 of the lifting device 5 reverses its action, pulling the feeding terminal 4 upward to reset. The trigger rod 6 then moves upward and approaches the induction switch 61, stopping the audible and visual alarm and indicating to the driver that the operation is complete and the vehicle can be moved.

[0062] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An environmentally friendly negative pressure conveying device for powder tank trucks, characterized in that, It includes a double-layer discharge gate valve, a transition chute, and a feeding terminal that are sequentially sealed and connected to the outlet of the storage silo along the material flow direction; the feeding terminal is fitted onto the outside of the transition chute in an axial sliding fit manner and is driven by a lifting device to make vertical displacement along the axis of the transition chute. The feeding terminal includes a composite feeding component, a material level monitoring component, and a self-cleaning dust collection component. The composite feeding component adopts a multi-layer sleeve structure, which includes a central material conveying channel, an annular jet air duct, and an outer peripheral dust extraction air duct arranged sequentially from the inside out. The air inlet of the annular jet air duct is sealed through a flexible air supply pipe, and the dust outlet of the outer peripheral dust extraction air duct is connected to a negative pressure dust extraction hose. An airflow guide ring is fixedly provided in the air outlet section of the annular jet air duct, and the outflow direction of the airflow guide ring points to the air inlet area of ​​the outer peripheral dust extraction air duct, thereby constructing a directional negative pressure adsorption field. The material level monitoring component includes a material probe, a low-pressure air supply module, and a differential pressure controller. The material probe is installed on the composite feeding component, and the detection end of the material probe extends to the bottom of the feeding component and is lower than the outlet plane of the central material conveying channel. The output end of the low-pressure air supply module is connected to the air inlet of the material probe and the sensing interface of the differential pressure controller through a three-way conversion connector. The self-cleaning dust collection assembly includes scrapers evenly distributed along the inner circumference of the outer periphery of the dust extraction duct, a pneumatic rotary drive unit installed at the end of the dust extraction duct, and a connecting rod connecting the scrapers and the pneumatic rotary drive unit.

2. The environmentally friendly negative pressure conveying device for powder tank trucks according to claim 1, characterized in that, The double-layer unloading gate valve includes a main valve and a secondary valve. The main valve is a metal hard-seal pneumatic stacked valve driven by a cylinder, and the secondary valve is a pneumatic powder stacked valve. The main valve and the secondary valve are connected by a connecting joint and the valve plate moves without interference. When opening the valve, the secondary valve is opened first and then the main valve is opened. When closing the valve, the main valve is closed first and then the secondary valve is closed after a delay.

3. The environmentally friendly negative pressure conveying device for powder tank trucks according to claim 1, characterized in that, The lifting device includes steel wire ropes, pulley blocks, and cylinders. There are three steel wire ropes, which are evenly distributed around the feeding terminal. The pulley block includes a horizontal pulley, a vertical guide pulley, and a three-groove pulley. One end of the three steel wire ropes is fixedly connected to the feeding terminal, and the other end of the three steel wire ropes is turned by the pulley block and then connected to the output end of the cylinder.

4. The environmentally friendly negative pressure conveying device for powder tank trucks according to claim 3, characterized in that, The feeding terminal is equipped with a trigger rod, and the transition chute is equipped with an induction switch for detecting the position of the trigger rod. When the feeding terminal descends, the trigger rod moves away from the induction switch, and the electrical control component activates an audible and visual alarm; when the lifting section rises, the trigger rod approaches the induction switch, and the alarm stops.

5. The environmentally friendly negative pressure conveying device for powder tank trucks according to claim 3, characterized in that, The detection end of the probe tube is equipped with an anti-stick cap. The anti-stick cap includes a connecting cylinder threaded inside the detection end and a dust baffle plate set on the top of the connecting cylinder. The dust baffle plate is uniformly provided with spiral grooves along the circumferential direction. The air inlet and outlet of the spiral grooves are staggered, and the cross-section of the spiral grooves decreases continuously along the gas flow direction.

6. The environmentally friendly negative pressure conveying device for powder tank trucks according to claim 1, characterized in that, The composite feeding assembly includes an inner cylinder, an annular sealing plate, a middle cylinder, and an outer cylinder. The inner cylinder is slidably assembled to the outer wall of the transition chute via an adapter seal. The annular sealing plate is fixedly connected to the outer wall of the inner cylinder. The middle cylinder and the outer cylinder are coaxially fixedly welded to the bottom of the annular sealing plate. A central material conveying channel is formed inside the inner cylinder. An annular jet air duct with an annular opening at the bottom is formed between the inner cylinder and the middle cylinder. An outer dust extraction air duct with an annular opening at the bottom is formed between the middle cylinder and the outer cylinder. The bottom of the outer cylinder is integrally formed with an outwardly expanding flared mouth. A first connector penetrating the outer cylinder is welded to the side wall of the middle cylinder. A second connector is welded to the side wall of the outer cylinder. The bottom plane of the inner cylinder is lower than the bottom plane of the outer cylinder, and the bottom plane of the outer cylinder is lower than the bottom plane of the middle cylinder.

7. The environmentally friendly negative pressure conveying device for powder tank trucks according to claim 6, characterized in that, The airflow guide ring is fixedly installed on the outer wall of the inner cylinder below the middle cylinder by welding or bolting. The installation position of the airflow guide ring corresponds to the bottom outlet of the annular jet air duct and the inlet of the outer peripheral dust extraction air duct. The top of the airflow guide ring is integrally formed with a smooth transition annular arc surface. The side of the airflow guide ring extends vertically upward to form a side ring. The side ring is located inside the outer peripheral dust extraction air duct between the middle cylinder and the outer cylinder.

8. The environmentally friendly negative pressure conveying device for powder tank trucks according to claim 6, characterized in that, The pneumatic rotary drive includes a pair of parallel rotating rings, with multiple spiral blades uniformly welded between the pair of rotating rings along the circumferential direction, and the pair of rotating rings are mounted on the inner wall of the middle cylinder via a thrust bearing.

9. The environmentally friendly negative pressure conveying device for powder tank trucks according to claim 1, characterized in that, The scraper has a groove along its length at its center, the working blade is specially treated for wear resistance, and the scraper maintains a constant contact pressure with the inner wall of the outer dust extraction duct.

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