Low-fluidity solid material conveying device and method

Abstract

The invention relates to the technical field of solid material conveying, and particularly discloses a low-fluidity solid material conveying device and method. The device comprises a stock bin, a supporting structure, an auxiliary arch breaking system, a vibration feeding mechanism and a control system. The auxiliary arch breaking system is integrated with a pneumatic impact device and a high-pressure gas injection device and is used for preventing or eliminating arching of materials; the vibration feeding mechanism is hung below the stock bin through an elastic element, and continuous and stable output of materials is achieved. The control system is in communication connection with the weighing module and all execution components, and intelligently regulates and controls cooperative operation of the low-frequency air hammer, the air cannon and the vibration motor according to material state parameters monitored in real time through a built-in arching risk assessment model and a discharging flow dynamic balance model, and staged and self-adaptive arching breaking and feeding control is achieved. The problems of arching and blocking of low-fluidity solid materials in the conveying process are effectively solved, and the conveying continuity, stability and automation level are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of solid material conveying, in particular to a low-flowability solid material conveying device and method. BACKGROUND

[0002] In the industrial fields of chemical industry, metallurgy, food and pharmaceutical industry, the storage and continuous conveying of solid materials are key links to ensure the automatic and continuous operation of production lines. Especially for low-flowability solid materials such as ammonium perchlorate, some powdery chemicals, and moist mineral powders, they have the characteristics of poor flowability and strong adhesion. During the discharging process of the silo (especially the weighing silo as a metering buffer unit), the "arch" (or "bridge") phenomenon is prone to occur. This phenomenon is due to the mechanical balance of the friction and adhesion between particles during gravity flow, which leads to the formation of a stable arch structure above the discharge port of the silo, thereby interrupting the flow.

[0003] Currently, the following technical means are commonly used in the industry to solve the problem of silo arching: Mechanical arch breaking device: such as installing a silo wall vibrator on the silo wall or setting a stirring paddle in the silo. However, the intense impact generated by the silo wall vibrator may adversely affect the measurement accuracy of the weighing module and even compact the material, exacerbating arching. Mechanical stirring has the problems of complex structure, easy damage to materials, difficulty in sealing driving components, and possible formation of "dead zones" or "bearing seizure" in viscous materials.

[0004] Pneumatic arch breaking device: such as using air cannons (or arch breakers) or continuously introducing fluidizing air. Air cannons use instantaneous release of high-pressure gas to impact the material arch, which has great power, but it is a passive and point-like intervention. If not used properly (such as frequency, timing, and direction), it not only consumes a lot of energy, but also may cause the material to be compacted or impact the silo structure. Continuous introduction of fluidizing air is not suitable for some materials that are easily absorbed or sensitive to moisture, and the energy consumption is continuous, which may cause dust to fly and pose a safety hazard.

[0005] Manual intervention: in an automated production line, when the discharging is not smooth, it still needs to rely on the operator to assist by knocking the silo wall or using a long stick to poke the material. This method not only has low efficiency, seriously wastes human resources, and increases labor intensity, but also poses a risk to personal safety and disrupts the automation and continuity of the production process.

[0006] In summary, existing single arch-breaking technologies suffer from drawbacks such as limited arch-breaking effect, poor adaptability, impact on metering accuracy, high energy consumption, or safety risks. They generally lack the ability to perceive and assess the actual state of the material within the silo, and cannot provide precise and coordinated intervention based on the degree of material flow obstruction and the specific location of arching. Therefore, there is an urgent need in this field for a low-flow-rate solid material conveying device and method capable of intelligently sensing the material flow status, automatically judging, and precisely executing arch-breaking actions. This would achieve efficient, stable, reliable, and fully automated material conveying, fundamentally eliminating reliance on manual intervention and improving the automation level and operational efficiency of the entire production system. Summary of the Invention

[0007] The purpose of this invention is to provide a conveying device and method for low-flow solid materials, in order to solve the problem mentioned in the background art that the prior art lacks a conveying device and method for low-flow solid materials that can intelligently sense the feeding status, automatically judge and accurately execute the arch-breaking action.

[0008] To achieve the above objectives, the present invention provides the following technical solution: A conveying device for low-flowability solid materials, comprising: A silo is used to hold low-flow solid materials. The support structure includes a bracket fixedly connected to the silo and a weighing module mounted on the bracket, wherein the weighing module is used to monitor the total weight of the silo and the material in real time. An auxiliary arch-breaking system, integrated into the silo, is used to prevent or eliminate material arching during the feeding process. The auxiliary arch-breaking system includes: a pneumatic impact device installed on the side wall of the silo, used to loosen the material by periodic mechanical vibration; and a high-pressure gas injection device, whose nozzle extends into the silo near the bottom area, used to inject high-pressure gas into the material layer to destroy the arch structure. A vibrating feeder mechanism is installed below the hopper to receive and continuously and stably output materials; the vibrating feeder mechanism is suspended on a fixed support by an elastic element and is equipped with a vibration drive source. A sealing connector is located between the hopper discharge port and the vibrating feeder inlet to achieve an airtight connection and prevent dust from escaping. The control system is communicatively connected to the weighing module, pneumatic impact device, high-pressure gas injection device, and vibration drive source, and is used to regulate the coordinated operation of each component according to the material state parameters.

[0009] Furthermore, the auxiliary arch-breaking system includes: A low-frequency air hammer is bolted to the wall of the silo and is used to loosen the material by periodic hammering. A high-pressure gas injection assembly consisting of an air cannon, an air cannon base, and an air cannon outlet pipe, wherein the air cannon base is connected to the silo, the air cannon is connected to the air cannon base, one end of the air cannon outlet pipe is connected to the air cannon, and the other end extends into the silo near the bottom area and is sealed and fixed, used to inject high-pressure gas into the material layer to destroy the arch bridge structure.

[0010] Furthermore, the vibrating feeder mechanism includes: A vibrating feeder is installed below the silo to receive and continuously convey materials; the feed inlet of the vibrating feeder is sealed to the discharge port of the silo via an anti-static flexible connection. The vibrating feeder support structure includes a hopper base fixed to a hopper support or the ground and a vibrating feeder support welded thereon. An elastic suspension mechanism is provided to suspend the vibrating feeder on the vibrating feeder support in a vibratory manner. The elastic suspension mechanism includes an air spring and a support bolt. The two ends of the air spring are respectively connected to the vibrating feeder and the vibrating feeder support, and compressed air is filled into the air spring during operation to provide elastic support. The support bolt is arranged in parallel next to the air spring to limit the downward displacement of the vibrating feeder in the absence of compressed air in order to protect the air spring. A vibratory motor is installed on the vibratory feeder to provide it with vibration power.

[0011] Furthermore, it also includes: The hopper cover is detachably installed on the top of the hopper to close the upper opening of the hopper; Furthermore, the control system communicates with the weighing module, low-frequency air hammer, air cannon, and vibration motor to dynamically adjust the working status of each actuator based on real-time monitoring data.

[0012] Furthermore, the air cannon's exhaust pipe extends along the inner wall of the hopper to a position near the hopper's discharge port, with its outlet angled downwards towards the hopper's central axis.

[0013] Furthermore, the control system is equipped with an assessment model that predicts arching risk based on the material stacking height. This model calculates the arching index under the current operating conditions using the following formula. :

[0014] in, : Arching index, when GI≥1, it is determined that there is a significant risk of arching; Material bulk density (kg / m³); : Gravitational acceleration (m / s²) : Height of material accumulation in the silo (m); Angle of repose of the material (rad); Unconfined compressive strength of the material (Pa); Minimum particle size of the material (m); : Diameter of the hopper discharge port (m); k: Empirical correction factor, ranging from 0.1 to 0.5, adjusted according to the material's adhesion.

[0015] Furthermore, the vibration frequency f and amplitude A of the vibratory motor are adaptively adjusted by the control system according to the real-time material flow rate requirement, and satisfy the following dynamic balance relationship:

[0016] Where Q: target instantaneous feed mass flow rate (kg / s); C: Equipment structural constant, which is related to the cross-sectional area of ​​the vibrating feeder and the material slip characteristics; A: Vibration amplitude in m; f: Vibration frequency (Hz); The equivalent drop height (m) is derived from the weight change rate measured by the weighing module. η: Conveying efficiency factor, ranging from 0.7 to 0.95, dynamically corrected according to material moisture content and static electricity level.

[0017] A method for conveying low-flow-rate solid materials, using the aforementioned low-flow-rate solid material conveying device, includes the following steps: Step S1: Add the low-flow solid material to be conveyed into the silo and monitor the material weight in real time through the weighing module; Step S2: The control system calculates the arching index GI based on the current material height h and preset material property parameters; Step S3: When GI < 0.8, only the vibrating feeder is activated to achieve normal material feeding; Step S4: When 0.8≤GI<1.0, start the low-frequency air hammer for periodic knocking, and start the vibrating feeder at the same time; Step S5: When GI≥1.0 or when the weighing module shows no change in weight for a long time, trigger the air cannon to perform a short-term spray, and then return to the control logic of step S4 or S3. Step S6: The control system adjusts the vibration frequency f and amplitude A of the vibrating motor in real time according to the target feed flow rate Q using the dynamic balance formula to ensure stable feeding. Step S7: During the operation of the air cannon, the hopper cover remains closed to prevent material from splashing. Step S8: When the system stops, the compressed air supply is turned off, the support bolts automatically bear the weight of the vibrating feeder, and the air spring is protected.

[0018] Furthermore, the control system periodically collects historical operating data and uses machine learning to optimize and update the empirical coefficient k and efficiency factor η in the formula, thereby improving control accuracy.

[0019] Compared with the prior art, the beneficial effects of the present invention are: (1) By combining pneumatic impact, high-pressure gas injection and vibratory feeding technologies, this device provides a phased mechanical disturbance and pneumatic arch breaking mechanism to address the arching phenomenon that is prone to occur in low-flow solid materials during gravity flow, effectively improving the flowability of materials and reducing the risk of blockage during the feeding process. (2) The integrated weighing module and control system can automatically adjust the start and stop of the arch breaking device and the feeding vibration parameters according to parameters such as material stacking height and weight change rate, combined with the preset arching criterion and flow control model, thereby reducing the dependence on manual intervention and ensuring the continuity of material conveying and metering accuracy. (3) The vibrating feeder adopts an elastic suspension structure and is equipped with a mechanical limit device. While ensuring stable vibration during normal operation, it prevents overload damage to the support components caused by air supply interruption. The whole system uses compressed air and electricity as power sources. It has a compact structure, is easy to maintain, and is suitable for quantitative conveying of solid materials with strong adhesion and poor flowability in chemical production environments. Attached Figure Description

[0020] Figure 1 This is a structural diagram from a first perspective of a low-flowability solid material conveying device according to the present invention; Figure 2 This is a structural diagram from a second perspective of a low-flowability solid material conveying device according to the present invention; Figure 3 This is a flowchart of a method for conveying low-flowability solid materials according to the present invention.

[0021] In the diagram: 1—hopper, 2—hopper support, 3—weighing module, 4—air cannon, 5—air cannon base, 6—air cannon outlet pipe, 7—low-frequency air hammer, 8—hopper discharge port, 9—vibrating feeder inlet, 10—vibrating feeder, 11—air spring, 12—vibrating motor, 13—support bolt, 14—hopper base, 15—vibrating feeder discharge port, 16—hopper cover, 17—vibrating feeder support. Detailed Implementation

[0022] 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.

[0023] Please see Figure 1 and Figure 2 This invention provides a specific embodiment of a conveying device for low-flow-rate solid materials. The device includes a hopper 1, a supporting structure, an auxiliary arch-breaking system, a vibrating feeding mechanism, sealing connectors, and a control system.

[0024] The silo 1 is used to hold low-flowability solid materials, such as ammonium perchlorate, moist mineral powder, and other materials with poor flowability. The supporting structure includes a silo bracket 2 fixedly connected to the silo 1 and a weighing module 3 mounted on the bracket. The weighing module 3 uses a high-precision sensor to monitor the total weight of the silo 1 and the materials in real time and transmits the data to the control system.

[0025] An auxiliary arch-breaking system is integrated into the silo 1 to prevent or eliminate material arching during the feeding process. The system includes a pneumatic impact device and a high-pressure gas injection device. The pneumatic impact device is specifically a low-frequency air hammer 7, bolted to the side wall or cone of the silo 1, which loosens the material through periodic mechanical vibration. The high-pressure gas injection device consists of an air cannon 4, an air cannon base 5, and an air cannon outlet pipe 6. The air cannon base 5 is welded or bolted to the silo 1, the air cannon 4 is fixed to the base, and one end of the air cannon outlet pipe 6 is connected to the air cannon 4, while the other end extends into the interior of the silo 1 near the bottom and is sealed. The air cannon outlet pipe 6 extends along the inner wall of the silo 1 to a position near the silo discharge port 8, with its outlet direction inclined downwards towards the central axis of the silo, to efficiently break the arch structure.

[0026] A vibrating feeder mechanism is located below the hopper 1 to receive and continuously and stably output materials. The vibrating feeder mechanism includes a vibrating feeder device 10, a vibrating feeder support structure, an elastic suspension mechanism, and a vibrating motor 12. The feed inlet 9 of the vibrating feeder device 10 is sealed to the hopper discharge port 8 via an anti-static flexible connection, forming a sealed connection to prevent dust escape and allow a certain degree of relative displacement. The vibrating feeder support structure includes a hopper base 14 fixed to the hopper support 2 or the ground, and a vibrating feeder support 17 welded thereto. The elastic suspension mechanism suspends the vibrating feeder device 10 vibratingly on the vibrating feeder support 17, and includes an air spring 11 and support bolts 13. The air spring 11 provides elastic support after being filled with compressed air, allowing the vibrating feeder device 10 to vibrate in the vertical direction; the support bolts 13 are arranged in parallel beside the air spring 11 to limit the downward displacement of the vibrating feeder device 10 when the system stops or the compressed air is interrupted, protecting the air spring 11 from damage. The vibratory motor 12 is installed on the vibratory feeder 10 to provide vibration power, and its frequency and amplitude are adjusted by the control system.

[0027] The top of the hopper 1 is equipped with a removable hopper cover 16, which is used to close the upper opening of the hopper and prevent material from splashing when the air cannon 4 is working.

[0028] The control system communicates with the weighing module 3, low-frequency air hammer 7, air cannon 4, and vibration motor 12, and uses a PLC or industrial computer for intelligent control. The control system incorporates an assessment model based on the material accumulation height to predict the risk of arching, and calculates the arching index using the following formula. :

[0029] in, : Arching index, when GI≥1, it is determined that there is a significant risk of arching; : Bulk density of material (kg / m³); : Gravitational acceleration (m / s²); : Height of material accumulation in the silo (m); Angle of repose of the material (rad); Unconfined compressive strength of the material (Pa); Minimum particle size of the material (m); : Diameter of the hopper discharge port (m); k: Empirical correction factor, ranging from 0.1 to 0.5, adjusted according to the material's adhesion.

[0030] Furthermore, the vibration frequency f and amplitude A of the vibratory motor are adaptively adjusted by the control system according to the real-time material flow rate requirement, and satisfy the following dynamic balance relationship:

[0031] Where Q: target instantaneous feed mass flow rate (kg / s); C: Equipment structural constant, which is related to the cross-sectional area of ​​the vibrating feeder and the material slip characteristics; A: Vibration amplitude (m); f: Vibration frequency (Hz); Equivalent drop height (m) is derived from the weight change rate measured by the weighing module. η: Conveying efficiency factor, ranging from 0.7 to 0.95, dynamically corrected according to material moisture content and static electricity level.

[0032] Please see Figure 3 The working principle of this low-flow-rate solid material conveying device is as follows: Step S1: Add the low-flow solid material to be conveyed into the silo and monitor the material weight in real time through the weighing module; Step S2: The control system calculates the arching index GI based on the current material height h and preset material property parameters; Step S3: When GI < 0.8, only the vibrating feeder is activated to achieve normal material feeding; Step S4: When 0.8≤GI<1.0, start the low-frequency air hammer for periodic knocking, and start the vibrating feeder at the same time; Step S5: When GI≥1.0 or when the weighing module shows no change in weight for a long time, trigger the air cannon to perform a short-term spray, and then return to the control logic of step S4 or S3. Step S6: The control system adjusts the vibration frequency f and amplitude A of the vibrating motor in real time according to the target feed flow rate Q using the dynamic balance formula to ensure stable feeding. Step S7: During the operation of the air cannon, the hopper cover remains closed to prevent material from splashing. Step S8: When the system stops, the compressed air supply is turned off, the support bolts automatically bear the weight of the vibrating feeder, and the air spring is protected.

[0033] In addition, the control system regularly collects operational data and optimizes the empirical coefficient k and efficiency factor η through machine learning algorithms to continuously improve control accuracy and adaptability.

[0034] This embodiment integrates sensing, decision-making, and execution units to achieve fully automated, continuous, and stable conveying of low-flow-rate solid materials, significantly improving the automation level and operating efficiency of the production line.

[0035] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A conveying device for low-flowability solid materials, characterized in that, include: The silo (1) is used to hold low-flow solid materials; The support structure includes a bracket fixedly connected to the silo (1) and a weighing module set on the bracket. The weighing module is used to monitor the total weight of the silo (1) and the material in real time. An auxiliary arch-breaking system is integrated on the silo (1) to prevent or eliminate material arching during the feeding process; the auxiliary arch-breaking system includes: a pneumatic impact device installed on the side wall of the silo (1) to loosen the material by periodic mechanical vibration; The high-pressure gas injection device has its nozzle extending into the bottom area of ​​the silo (1) to inject high-pressure gas into the material layer to destroy the arch bridge structure. A vibrating feeder mechanism is installed below the hopper to receive and continuously and stably output materials; the vibrating feeder mechanism is suspended on a fixed support by an elastic element and is equipped with a vibration drive source. A sealing connector is provided between the hopper discharge port (8) and the vibrating feeder inlet (9) to achieve an airtight connection and prevent dust from escaping. The control system is communicatively connected to the weighing module, pneumatic impact device, high-pressure gas injection device, and vibration drive source, and is used to regulate the coordinated operation of each component according to the material state parameters.

2. The low-flowability solid material conveying device according to claim 1, characterized in that, The auxiliary arch-breaking system includes: A low-frequency air hammer (7) is bolted to the wall of the silo (1) and is used to loosen the material by periodic hammering. The high-pressure gas injection assembly consists of an air cannon (4), an air cannon base (5), and an air cannon outlet pipe (6). The air cannon base (5) is connected to the silo (1), the air cannon (4) is connected to the air cannon base (5), and one end of the air cannon outlet pipe (6) is connected to the air cannon (4), while the other end extends into the silo (1) near the bottom and is sealed and fixed. It is used to inject high-pressure gas into the material layer to destroy the arch bridge structure.

3. The low-flowability solid material conveying device according to claim 1, characterized in that, The vibrating feeder mechanism includes: A vibrating feeder (10) is installed below the silo (1) for receiving and continuously conveying materials; the feed inlet (9) of the vibrating feeder (10) is sealed and connected to the discharge port (8) of the silo through an anti-static soft connection; The vibrating feeder support structure includes a hopper base (14) fixed to the hopper support (2) or the ground and a vibrating feeder support (17) welded thereon. An elastic suspension mechanism is provided to suspend the vibrating feeder (10) vibratingly on the vibrating feeder support (17). The elastic suspension mechanism includes an air spring (11) and a support bolt (13). The air spring (11) is connected to the vibrating feeder (10) and the vibrating feeder support (17) at both ends, and is filled with compressed air to provide elastic support during operation. The support bolt (13) is arranged in parallel next to the air spring (11) to limit the downward displacement of the vibrating feeder (10) in the absence of compressed air in order to protect the air spring (11). A vibratory motor (12) is installed on the vibratory feeder (10) to provide it with vibration power.

4. The low-flowability solid material conveying device according to claim 1, characterized in that, It also includes: a hopper cover (16), which is detachably installed on the top of the hopper (1) for closing the upper opening of the hopper.

5. A low-flowability solid material conveying device according to claim 1, characterized in that, The control system is connected to the weighing module (3), low-frequency air hammer (7), air cannon (4) and vibration motor (12) for dynamically adjusting the working status of each actuator based on real-time monitoring data.

6. The low-flowability solid material conveying device according to claim 1, characterized in that, The air cannon outlet pipe (6) extends along the inner wall of the silo (1) to a position close to the silo discharge port (8), and its outlet direction is inclined downward towards the central axis of the silo.

7. The low-flowability solid material conveying device according to claim 1, characterized in that, The control system is equipped with an assessment model that predicts arching risk based on the material stacking height. This model calculates the arching index under the current operating conditions using the following formula. : in, : Arching index, when GI≥1, it is determined that there is a significant risk of arching; Material bulk density (kg / m³); : Gravitational acceleration (m / s²) : Height of material accumulation in the silo (m); Angle of repose of the material (rad); Unconfined compressive strength of the material (Pa); Minimum particle size of the material (m); : Diameter of the hopper discharge port (m); k: Empirical correction factor, ranging from 0.1 to 0.5, adjusted according to the material's adhesion.

8. A low-flowability solid material conveying device according to claim 1, characterized in that, The vibration frequency f and amplitude A of the vibrating motor (12) are adaptively adjusted by the control system according to the real-time material flow rate requirement, and satisfy the following dynamic balance relationship: Where Q: target instantaneous feed mass flow rate (kg / s); C: Equipment structural constant, which is related to the cross-sectional area of ​​the vibrating feeder and the material slip characteristics; A: Vibration amplitude in m; f: Vibration frequency (Hz); The equivalent drop height (m) is derived from the weight change rate measured by the weighing module. η: Conveying efficiency factor, ranging from 0.7 to 0.95, dynamically corrected according to material moisture content and static electricity level.

9. A method for conveying low-flow-rate solid materials, using the low-flow-rate solid material conveying device as described in any one of claims 1-8, characterized in that, Includes the following steps: Step S1: Add the low-flow solid material to be transported into the silo (1) and monitor the weight of the material in real time through the weighing module (3); Step S2: The control system calculates the camber index based on the current material height h and preset material property parameters. ; Step S3: When GI < 0.8, only the vibrating feeder (10) is activated to achieve normal feeding; Step S4: When 0.8≤GI<1.0, start the low-frequency air hammer (7) to perform periodic knocking, and at the same time start the vibrating feeder (10). Step S5: When GI≥1.0 or when the weighing module (3) shows that the weight has not changed for a long time, trigger the air cannon (4) to spray for a short time, and then return to the control logic in step S3 or S4. Step S6: The control system adjusts the vibration frequency f and amplitude A of the vibrating motor (12) in real time according to the target feed flow rate Q using the dynamic balance relationship formula to ensure stable feeding; Step S7: During the operation of the air cannon (4), the hopper cover (16) remains closed to prevent material from splashing; Step S8: When the system stops, the compressed air supply is turned off, the support bolt (13) automatically bears the weight of the vibrating feeder (10), and the air spring (11) is protected.

10. A method for conveying low-flowability solid materials according to claim 9, characterized in that, The control system periodically collects historical operating data and uses machine learning to optimize and update the empirical coefficient k and efficiency factor η in the formula, thereby improving control accuracy.

Images