A method and system for reducing the discharge fluctuation of spiral conveying materials for loss-in-weight scale

Abstract

This invention discloses a method and system for reducing material discharge fluctuations in a screw conveyor used in a loss-in-weight scale. The method includes the following steps: 1. Optimizing the conveying parameters of the screw conveyor using genetic algorithms or other optimization algorithms to ensure high conveying capacity; 2. Optimizing the structural parameters of the hopper using genetic algorithms or other optimization algorithms to reduce the fluctuation in the amount of material falling from the hopper outlet; 3. Setting up an anti-blocking mechanism to monitor the material in the hopper in real time and handle material blockage issues. The method and system described in this invention can effectively reduce the fluctuation of output material while ensuring high material conveying capacity, improving the efficiency of process production and possessing high practical value.

Description

Technical Field

[0001] The invention relates to the field of reducing material fluctuations, and in particular to a system and a method for reducing the discharge fluctuations of spiral conveying materials for a loss-in-weight scale. Background Art

[0002] Loss-in-weight weighing is an automated control device developed based on static weighing. It is commonly used in the batching of production processes in industries such as metallurgy and chemical engineering, such as the metering and distribution of powders and granules. Loss-in-weight weighing can be used for continuous batching with flow control, controlling a certain material flow rate to add a specified mass of material to the downstream device for continuous production processes.

[0003] The principle of loss-in-weight weighing is to monitor the quality of the metering bin and the screw conveyor in real time, and calculate the amount of distributed materials by the quality difference. When the screw conveyor outputs materials, the material output will be uneven, that is, the fluctuation is large, which will lead to the instability of the monitoring data of the loss-in-weight weighing device, and then affect the material metering and distribution. At the same time, due to the instability of the screw conveyor's discharge, the material fluctuation problem also affects the stability of the spray gun spraying materials into the smelting furnace, affecting industrial production efficiency. Summary of the invention

[0004] In view of the above-mentioned technical deficiencies, the object of the present invention is to provide a system and method for reducing the discharge fluctuation of a spiral conveyor material for a loss-in-weight scale, which can increase the stability of the loss-in-weight weighing reading and ensure production efficiency.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] The present invention provides a system for reducing the discharge fluctuation of a spiral conveying material for a loss-in-weight scale, comprising a spiral tube provided with spiral blades, a fluctuation reducing mechanism adapted to the spiral tube is provided below a discharge port thereof, the fluctuation reducing mechanism comprises a funnel, a plurality of piezoelectric sensors are provided at the lower edge of a feed port of the funnel, the piezoelectric sensors are used for real-time weight loss weighing monitoring of the funnel and the material in the funnel, the discharge port of the funnel is composed of a plurality of movable blades that can be turned outward, and the movable blades can be opened to allow the blocked material in the funnel to fall quickly.

[0007] Preferably, the movable fan blades control their rotation angle through a turning mechanism connected to their upper ends. The distance between the turning mechanism and the bottom of the funnel slope is two-thirds of the total length of the slope. The number of the movable fan blades is three. Driven by the turning mechanism, the movable fan blades can rotate outward at a maximum of 15° with the upper end of the movable fan blade as the center. The turning mechanism is electrically connected to the controller.

[0008] Preferably, the discharge port of the spiral tube is connected to the feed port of the funnel through a flexible tube. The diameter of the funnel feed port is 600 mm. The upper surface of the funnel feed port is 80 mm to 100 mm below the discharge port of the spiral tube. The installation ensures that the cone center axis of the funnel is vertical.

[0009] The present invention also provides a method for reducing the discharge fluctuation of a spiral conveying material discharge system for a loss-in-weight scale, comprising the following steps:

[0010] Step 1: Determine the spiral conveying capacity of the spiral tube; the mathematical model of the spiral conveying capacity is as follows:

[0011]

[0012] Where D is the nominal diameter of the spiral blade, H is the pitch of the spiral shaft, is the filling rate of the conveyed material particles, n is the speed of the spiral blade, C is the inclination coefficient of the screw conveyor, and ρ is the unit volume mass of the material;

[0013] Step 2: According to the simulation, the real-time fluctuation of the material falling within a spiral blade pitch is obtained, and the average amount of material conveyed within a cycle is calculated.

[0014]

[0015] q i t i The amount of material at the moment, t is the time of one pitch rotation cycle of the spiral blade, is the average value of the material quantity within t;

[0016] Step 3: Establish the funnel accumulation model, t b is the moment when the material starts to fall in a cycle, t e is the moment when all materials fall within a cycle. The funnel accumulation model is as follows:

[0017] The t of the previous cycle e -0.1s = t of the next cycle b ;

[0018] Step 4: Optimize the angle (α) between the conical slope of the funnel and the vertical line, the funnel outlet diameter (d), and the funnel depth (h) in multiple parameters to form the funnel body in the fluctuation reduction mechanism.

[0019] Preferably, in step 4, the optimization steps are as follows:

[0020] (1) Determine the optimization target of the screw conveying capacity; according to step 1, take the screw conveying capacity Q as the optimization target function;

[0021] (2) Determine the constraints for optimizing the screw conveying parameters. Assume that the constraint function is g m (x):

[0022]

[0023] g1(x) is the power limit of the conveyor: that is, the power loss requirement of the screw conveyor under load operation, where P m is the rated power of the motor, P is the power of the screw conveyor under load operation conditions, V is the conveying volume, L is the conveying distance, S is the inclined height, μ is the operating resistance coefficient, ξ is the power reserve coefficient, β is the friction angle, and η is the transmission efficiency of the motor;

[0024] g2(x) is the stiffness limit: that is, the maximum deflection of the screw conveyor should be lower than the allowable value, where f max is the maximum deflection of the screw conveyor, [f] is the maximum allowable deflection;

[0025] g3(x) is the speed limit of the conveyor: where n is the current speed of the screw, n min is the minimum permissible speed, n max For the maximum permissible speed, set n min =50r / m,n max =120r / m;

[0026] g4(x) is the limit of the torsional strength of the conveyor: where τ is the ultimate shear stress of the conveyor screw shaft, and [τ] is the allowable shear stress;

[0027] g5(x) is the conveyor efficiency limit: where η is the conveying efficiency of the screw conveyor, and [η] is the minimum conveying efficiency allowed by the screw conveyor;

[0028] (3) According to steps (1) and (2), the optimal transportation scheme is obtained:

[0029]

[0030] Among them, D m is the optimized nominal diameter of the spiral blade, H m For the optimized pitch of the helical axis, To optimize the filling rate of the conveying material particles, n m The optimized rotation speed of the spiral blades;

[0031] (4) The transport plan obtained according to step (3) Optimize the funnel structure and determine the optimization target of the funnel fluctuation performance:

[0032]

[0033] Among them, PU P is the average amount of material at the discharge peak of the hopper discharge port when the material continues to fall steadily. D is the average amount of material in the trough of the discharge port of the hopper, It is the average amount of material discharged from the hopper discharge port when the material continues to fall steadily. C is the fluctuation performance value, 0≤C≤2. The closer C is to 0, the smaller the material fluctuation is, and the closer it is to 2, the greater the fluctuation is.

[0034] (5) Determine the constraints for funnel parameter optimization. Assume that the constraint function is e m (x):

[0035]

[0036] Among them, e1(x) is the average material quantity limit; fluctuation performance limit: e2(x): 0≤C≤2; e3(x) is the angle limit between the conical slope of the funnel and the vertical line; e4(x) is the funnel outlet diameter limit; e5(x) is the funnel depth limit.

[0037] (6) According to steps (4) and (5), the optimal parameter scheme of the funnel mechanism is obtained:

[0038]

[0039] Among them, α m is the optimal angle between the cone slope of the funnel and the vertical line, h m Optimize the depth of the funnel, d m Optimize the outlet diameter for the funnel.

[0040] The present invention also provides a method for preventing blocking of a material discharge fluctuation system of a spiral conveyor for a loss-in-weight scale, comprising the following steps:

[0041] Step 1: Install three evenly distributed piezoelectric sensors on the funnel, the piezoelectric sensors are electrically connected to the controller, and the controller is electrically connected to the buzzer;

[0042] Step 2: Monitor the funnel for blockage, including the following steps:

[0043] (1) Three evenly distributed piezoelectric sensors are used to monitor the mass of the funnel and the material in the funnel in real time. Assuming that the real-time monitoring values ​​of the three piezoelectric sensors are m1, m2, and m3 respectively, the total mass is ∑(m1, m2, m3);

[0044] (2) The mass threshold is set as [m] in the controller. When the total mass ∑(m1, m2, m3) calculated in step (1) is greater than the mass threshold [m], it is determined that the funnel discharge port is blocked; otherwise, the funnel discharge port is not blocked and step (1) is repeated;

[0045] Step 3: When a blockage occurs, the controller issues a command, the transfer mechanism drives the movable fan blades to open, and the buzzer sounds an alarm;

[0046] Step 4: The controller controls the transfer mechanism to drive the movable fan blades to close, and the controller controls the buzzer to cancel the alarm, and repeats steps 1 and 2.

[0047] Preferably, a data processor is used to implement step 1 and step 2, and the data processor includes a calculation module and a comparison module.

[0048] The calculation module calculates the sum of the real-time monitoring data of the three piezoelectric sensors ∑(m1, m2, m3) according to the summation formula stored inside it.

[0049] The comparison module determines whether ∑(m1, m2, m3) is greater than [m], and when the judgment result is "Y", a blocking instruction is output.

[0050] Preferably, the motor drive is used to implement step 3 and step 4, and the motor drive includes an execution module and a recovery module.

[0051] The execution module, under the input of the blocking instruction, converts it into an electrical signal to make the motor work, and the motor drives the transfer mechanism to work and open the movable fan blades;

[0052] The recovery module outputs a recovery instruction delayed by 5s at the end of the material blocking instruction delayed by 5s, which is converted into an electrical signal to make the motor work, and the motor drives the transfer mechanism to close the movable fan blades.

[0053] The beneficial effects of the present invention are:

[0054] 1. The present invention optimizes the spiral conveying parameters of the spiral tube through a genetic algorithm to obtain conveying parameters with high conveying performance, which can effectively improve the conveying performance of the spiral tube and improve production efficiency;

[0055] 2. The present invention optimizes the structural parameters of the funnel to reduce the fluctuation of the material, thereby improving the stability of the material falling from the funnel. The material falling from the funnel is sprayed into the smelting furnace under the action of the spray gun, thereby improving the stability of the amount of material sprayed into the smelting furnace by the spray gun and reducing the consumption of smelting energy;

[0056] 3. The system and method for setting anti-blocking materials provided by the present invention replace traditional manual monitoring. At the same time, when blockage occurs, it can also automatically handle the blockage problem, replacing manual dredging, improving safety and production efficiency, reducing the labor form of workers, and saving labor time. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0058] Figure 1 A schematic diagram of the structure of a system for reducing the discharge fluctuation of a spiral conveying material for a loss-in-weight scale provided by an embodiment of the present invention;

[0059] Figure 2 A front view of a fluctuation reduction mechanism provided by an embodiment of the present invention;

[0060] Figure 3 A bottom view of a fluctuation reduction mechanism provided by an embodiment of the present invention;

[0061] Figure 4 A flow chart of a method for reducing the blocking of a material discharge fluctuation system of a spiral conveyor for a loss-in-weight scale provided by an embodiment of the present invention;

[0062] Figure 5 A schematic diagram of an open movable fan blade provided by an embodiment of the present invention;

[0063] Figure 6 A genetic algorithm optimization flow chart provided for an embodiment of the present invention;

[0064] Figure 7 A material fluctuation diagram at a funnel outlet provided by an embodiment of the present invention;

[0065] Figure 8 This is a simulation comparison diagram of the original material fluctuation and the reduced fluctuation provided in an embodiment of the present invention.

[0066] Description of reference numerals:

[0067] 1- spiral tube, 2- spiral blade, 3- fluctuation reduction mechanism, 301- piezoelectric sensor, 302- funnel, 303- turning mechanism, 304- movable fan blade. DETAILED DESCRIPTION

[0068] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0069] like Figures 1 to 8As shown, an embodiment of the present invention provides a system for reducing the discharge fluctuation of a spiral conveying material for a loss-in-weight scale, comprising a spiral tube 1 provided with a spiral blade 2, a fluctuation reducing mechanism 3 adapted thereto is provided below the discharge port of the spiral tube 1, the fluctuation reducing mechanism 3 comprises a funnel 302, a plurality of piezoelectric sensors 301 are provided at the lower edge of the feed port of the funnel 302, the piezoelectric sensors 301 are used for real-time loss-in-weight weighing monitoring of the funnel 302 and the material in the funnel 302, the discharge port of the funnel 302 is composed of a plurality of movable blades 304 that can be flipped outward, and the movable blades can be opened to allow the material blocked in the funnel to fall quickly.

[0070] The movable blade 304 is controlled to rotate at an angle by a turning mechanism 303. The distance between the turning mechanism and the bottom of the funnel slope is two-thirds of the total length of the slope. The lower end of the funnel is evenly divided into three identical movable blades 304. The upper end of the movable blade 304 is connected to the turning mechanism. Driven by the turning mechanism, the movable blade 304 can rotate outward at a maximum of 15° with the upper end of the movable blade as the center. The turning mechanism uses a drive motor, which is electrically connected to a controller, such as Figure 5 , the dotted line position is the position where the movable fan blades are opened.

[0071] The discharge port of the spiral tube 1 is connected to the feed port of the funnel 302 through a flexible tube. The diameter of the funnel feed port is 600 mm. The upper surface of the funnel feed port is 80 mm to 100 mm below the discharge port of the spiral tube. The installation ensures that the cone center axis of the funnel is vertical.

[0072] The embodiment of the present invention also provides a method for reducing the discharge fluctuation of a spiral conveying material discharge system for a loss-in-weight scale, comprising the following steps:

[0073] Step 1: Determine the spiral conveying capacity of the spiral tube 1; the mathematical model of the spiral conveying capacity is as follows:

[0074]

[0075] Where D is the nominal diameter of the spiral blade, H is the pitch of the spiral shaft, is the filling rate of the conveyed material particles, n is the speed of the spiral blade, C is the inclination coefficient of the screw conveyor, and ρ is the unit volume mass of the material;

[0076] Step 2: According to the simulation, the real-time fluctuation of the material falling within a spiral blade pitch is obtained, and the average amount of material conveyed within a cycle is calculated.

[0077]

[0078] q i is the amount of material at time ti, t is the time of one pitch rotation cycle of the spiral blade, is the average value of the material quantity within t;

[0079] Step 3: Establish the funnel accumulation model, t b is the moment when the material starts to fall in a cycle, t e is the moment when all materials fall within a cycle. The funnel accumulation model is as follows:

[0080] The t of the previous cycle e -0.1s = t of the next cycle b ;

[0081] Step 4: Optimize the angle (α) between the conical slope of the funnel and the vertical line, the funnel outlet diameter (d), and the funnel depth (h) in multiple parameters to form the funnel body in the fluctuation reduction mechanism.

[0082] In step 4, the optimization steps are as follows:

[0083] (1) Determine the optimization target of the screw conveying capacity; according to step 1, take the screw conveying capacity Q as the optimization target function;

[0084] (2) Determine the constraints for optimizing the screw conveying parameters. Assume that the constraint function is g m (x):

[0085]

[0086] g1(x) is the power limit of the conveyor: that is, the power loss requirement of the screw conveyor under load operation, where P m is the rated power of the motor, P is the power of the screw conveyor under load operation conditions, V is the conveying volume, L is the conveying distance, S is the inclined height, μ is the operating resistance coefficient, ξ is the power reserve coefficient, β is the friction angle, and η is the transmission efficiency of the motor;

[0087] g2(x) is the stiffness limit: that is, the maximum deflection of the screw conveyor should be lower than the allowable value, where f max is the maximum deflection of the screw conveyor, [f] is the maximum allowable deflection;

[0088] g3(x) is the speed limit of the conveyor: where n is the current speed of the screw, n min is the minimum permissible speed, n max For the maximum permissible speed, set n min =50r / m,n max =120r / m;

[0089] g4(x) is the limit of the torsional strength of the conveyor: where τ is the ultimate shear stress of the conveyor screw shaft, and [τ] is the allowable shear stress;

[0090] g5(x) is the conveyor efficiency limit: where η is the conveying efficiency of the screw conveyor, and [η] is the minimum conveying efficiency allowed by the screw conveyor;

[0091] (3) According to steps (1) and (2), the optimal transportation scheme is obtained:

[0092]

[0093] Among them, D m is the optimized nominal diameter of the spiral blade, H m For the optimized pitch of the helical axis, To optimize the filling rate of the conveying material particles, n m The optimized rotation speed of the spiral blades;

[0094] (4) The transport plan obtained according to step (3) In order to reduce the volatility of the material, a fluctuation reduction mechanism 3 is provided below the discharge port of the spiral tube 1. The present invention optimizes the structural parameters of the fluctuation reduction by using genetic optimization algorithms and other optimization algorithms, so that the fluctuation of the material falling from the discharge port of the fluctuation reduction mechanism 3 is minimized, and the optimization target of the funnel fluctuation performance is determined:

[0095]

[0096] Among them, P U P is the average amount of material at the discharge peak of the hopper discharge port when the material continues to fall steadily. D is the average amount of material in the trough of the discharge port of the hopper, It is the average amount of material discharged from the hopper discharge port when the material continues to fall steadily. C is the fluctuation performance value, 0≤C≤2. The closer C is to 0, the smaller the material fluctuation is, and the closer it is to 2, the greater the fluctuation is.

[0097] (5) Determine the constraints for funnel parameter optimization. Assume that the constraint function is e m (x):

[0098]

[0099] Among them, e1(x) is the average material quantity limit; fluctuation performance limit: e2(x): 0≤C≤2; e3(x) is the angle limit between the conical slope of the funnel and the vertical line; e4(x) is the funnel outlet diameter limit; e5(x) is the funnel depth limit.

[0100] (6) According to steps (4) and (5), the optimal parameter scheme of the funnel mechanism is obtained:

[0101]

[0102] Among them, α mis the optimal angle between the cone slope of the funnel and the vertical line, h m Optimize the depth of the funnel, d m Optimize the outlet diameter for the funnel.

[0103] In order to solve the problem of material blocking when the fluctuation reduction mechanism 3 is working, the embodiment of the present invention also provides a method for reducing the blocking of the material discharge fluctuation system of the spiral conveyor for the loss-in-weight scale, comprising the following steps:

[0104] Step 1: Install three evenly distributed piezoelectric sensors on the funnel, the piezoelectric sensors are electrically connected to the controller, and the controller is electrically connected to the buzzer;

[0105] Step 2: Monitor the funnel for blockage, including the following steps:

[0106] (1) Three evenly distributed piezoelectric sensors are used to monitor the mass of the funnel and the material in the funnel in real time. Assuming that the real-time monitoring values ​​of the three piezoelectric sensors are m1, m2, and m3 respectively, the total mass is ∑(m1, m2, m3);

[0107] (2) The mass threshold is set as [m] in the controller. When the total mass ∑(m1, m2, m3) calculated in step (1) is greater than the mass threshold [m], it is determined that the funnel discharge port is blocked; otherwise, the funnel discharge port is not blocked and step (1) is repeated;

[0108] Step 3: When a blockage occurs, the controller issues a command, the transfer mechanism drives the movable fan blades to open, and the buzzer sounds an alarm;

[0109] Step 4: The controller controls the transfer mechanism to drive the movable fan blades to close, and the controller controls the buzzer to cancel the alarm, and repeats steps 1 and 2.

[0110] A data processor is used to implement step 1 and step 2, wherein the data processor includes a calculation module and a comparison module.

[0111] The calculation module calculates the sum of the real-time monitoring data of the three piezoelectric sensors ∑(m1, m2, m3) according to the summation formula stored inside it.

[0112] The comparison module determines whether ∑(m1, m2, m3) is greater than [m], and when the judgment result is "Y", a blocking instruction is output.

[0113] The motor drive is used to implement step 3 and step 4, and the motor drive includes an execution module and a recovery module.

[0114] The execution module, under the input of the blocking instruction, converts it into an electrical signal to make the motor work, and the motor drives the transfer mechanism to work and open the movable fan blades;

[0115] The recovery module outputs a recovery instruction delayed by 5s at the end of the material blocking instruction delayed by 5s, which is converted into an electrical signal to make the motor work, and the motor drives the transfer mechanism to close the movable fan blades.

[0116] like Figure 8 As shown, the fluctuation of the material in the spiral tube 1 without passing through the fluctuation reduction mechanism 3 and passing through the fluctuation reduction mechanism 3 are simulated by simulation software. The figure shows that the falling fluctuation of the material passing through the fluctuation reduction mechanism 3 is smaller, which further verifies the applicability of the method and system of the present invention.

[0117] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for reducing the discharge fluctuation of a spiral conveyor for a loss-in-weight scale, characterized in that: A discharge fluctuation system is adopted, the system includes a spiral tube with spiral blades, characterized in that a fluctuation reduction mechanism adapted to the spiral tube is provided below the discharge port, the fluctuation reduction mechanism includes a funnel, a plurality of piezoelectric sensors are provided at the lower edge of the feed port of the funnel, the piezoelectric sensors are used to perform real-time weight loss weighing monitoring of the funnel and the material in the funnel, the discharge port of the funnel is composed of a plurality of movable blades that can be turned outward, and the movable blades can be opened to allow the blocked material in the funnel to fall quickly; The movable fan blade controls its rotation angle through a turning mechanism connected to its upper end. The distance between the turning mechanism and the bottom of the funnel slope is two-thirds of the total length of the slope. The number of the movable fan blades is three. Driven by the turning mechanism, the movable fan blade can be rotated outward by a maximum of 15° with the upper end of the movable fan blade as the center. The turning mechanism is electrically connected to the controller. The method comprises the following steps: Step 1: Determine the spiral conveying capacity of the spiral tube; the mathematical model of the spiral conveying capacity is as follows: Where D is the nominal diameter of the spiral blade, H is the pitch of the spiral shaft, is the filling rate of the conveyed material particles, n is the speed of the spiral blade, C is the inclination coefficient of the screw conveyor, and ρ is the unit volume mass of the material; Step 2: According to the simulation, the real-time fluctuation of the material falling within a spiral blade pitch is obtained, and the average amount of material conveyed within a cycle is calculated. q i is the amount of material at time ti, t is the time of one pitch rotation cycle of the spiral blade, is the average value of the material quantity within t; Step 3: Establish the funnel accumulation model, t b is the moment when the material starts to fall in a cycle, t e is the moment when all materials fall within a cycle. The funnel accumulation model is as follows: The t of the previous cycle e -0.1s = t of the next cycle b ; Step 4: Optimize the angle (α) between the cone slope of the funnel and the vertical line, the funnel outlet diameter (d), and the funnel depth (h) to form the funnel body in the fluctuation reduction mechanism; The optimization steps are as follows: (1) Determine the optimization target of the screw conveying capacity; according to step 1, take the screw conveying capacity Q as the optimization target function; (2) Determine the constraints for optimizing the screw conveying parameters. Assume that the constraint function is g m (x): g1(x) is the power limit of the conveyor: that is, the power loss requirement of the screw conveyor under load operation, where P m is the rated power of the motor, P is the power of the screw conveyor under load operation conditions, V is the conveying volume, L is the conveying distance, S is the inclined height, μ is the operating resistance coefficient, ξ is the power reserve coefficient, β is the friction angle, and η is the transmission efficiency of the motor; g2(x) is the stiffness limit: that is, the maximum deflection of the screw conveyor should be lower than the allowable value, where f max is the maximum deflection of the screw conveyor, [f] is the maximum allowable deflection; g3(x) is the speed limit of the conveyor: where n is the current speed of the screw, n min is the minimum permissible speed, n max For the maximum permissible speed, set n min =50r / m,n max =120r / m; g4(x) is the limit of the torsional strength of the conveyor: where τ is the ultimate shear stress of the conveyor screw shaft, and [τ] is the allowable shear stress; g5(x) is the conveyor efficiency limit: where η is the conveying efficiency of the screw conveyor, and [η] is the minimum conveying efficiency allowed by the screw conveyor; (3) According to steps (1) and (2), the optimal transportation scheme is obtained: Among them, D m is the optimized nominal diameter of the spiral blade, H m For the optimized pitch of the helical axis, To optimize the filling rate of the conveying material particles, n m The optimized rotation speed of the spiral blades; (4) The transport plan obtained according to step (3) Optimize the funnel structure and determine the optimization target of the funnel fluctuation performance: Among them, P U P is the average amount of material at the discharge peak of the hopper discharge port when the material continues to fall steadily. D is the average amount of material in the trough of the discharge port of the hopper, It is the average amount of material discharged from the hopper discharge port when the material continues to fall steadily. C is the fluctuation performance value, 0≤C≤2. The closer C is to 0, the smaller the material fluctuation is, and the closer it is to 2, the greater the fluctuation is. (5) Determine the constraints for funnel parameter optimization. Assume that the constraint function is e m (x): Among them, e1(x) is the material average quantity limit; fluctuation performance limit: e2(x): 0≤C≤2; e3(x) is the angle limit between the cone slope of the funnel and the vertical line; e4(x) is the funnel outlet diameter limit; e5(x) is the funnel depth limit; (6) According to steps (4) and (5), the optimal parameter scheme of the funnel mechanism is obtained: Among them, α m is the optimal angle between the cone slope of the funnel and the vertical line, h m Optimize the depth of the funnel, d m Optimize the outlet diameter for the funnel.

2. The method according to claim 1, characterized in that The following steps are involved: Step 1: Install three evenly distributed piezoelectric sensors on the funnel, the piezoelectric sensors are electrically connected to the controller, and the controller is electrically connected to the buzzer; Step 2: Monitor the funnel for blockage, including the following steps: (1) Three evenly distributed piezoelectric sensors are used to monitor the mass of the funnel and the material in the funnel in real time. Assuming that the real-time monitoring values ​​of the three piezoelectric sensors are m1, m2, and m3 respectively, the total mass is ∑(m1, m2, m3); (2) The mass threshold is set as [m] in the controller. When the total mass ∑(m1, m2, m3) calculated in step (1) is greater than the mass threshold [m], it is determined that the funnel discharge port is blocked; otherwise, the funnel discharge port is not blocked and step (1) is repeated; Step 3: When a blockage occurs, the controller issues a command, the transfer mechanism drives the movable fan blades to open, and the buzzer sounds an alarm; Step 4: The controller controls the transfer mechanism to drive the movable fan blades to close, and the controller controls the buzzer to cancel the alarm, and repeats steps 1 and 2.

3. The method according to claim 2, characterized in that A data processor is used to implement step 1 and step 2, wherein the data processor includes a calculation module and a comparison module. The calculation module calculates the sum of the real-time monitoring data of the three piezoelectric sensors ∑(m1, m2, m3) according to the summation formula stored inside it. The comparison module determines whether ∑(m1, m2, m3) is greater than [m], and when the judgment result is "Y", a blocking instruction is output.

4. The method according to claim 3, characterized in that The motor drive is used to implement step 3 and step 4, and the motor drive includes an execution module and a recovery module. The execution module, under the input of the blocking instruction, converts it into an electrical signal to make the motor work, and the motor drives the transfer mechanism to work and open the movable fan blades; The recovery module outputs a recovery instruction delayed by 5s at the end of the material blocking instruction delayed by 5s, which is converted into an electrical signal to make the motor work, and the motor drives the transfer mechanism to close the movable fan blades.

5. The method according to claim 1, characterized in that The discharge port of the spiral tube is connected to the feed port of the funnel through a flexible tube. The diameter of the funnel feed port is 600 mm. The upper surface of the funnel feed port is 80 mm to 100 mm below the discharge port of the spiral tube. The installation ensures that the cone center axis of the funnel is vertical.

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