CN110711507B

CN110711507B - Screw type multi-component material batching device controller

Info

Publication number: CN110711507B
Application number: CN201910965554.8A
Authority: CN
Inventors: 邹细勇; 夏浩; 金尚忠
Original assignee: China Jiliang University
Current assignee: China Jiliang University
Priority date: 2017-09-19
Filing date: 2017-09-19
Publication date: 2021-10-22
Anticipated expiration: 2037-09-19
Also published as: CN110711507A; CN107715727A; CN107715727B

Abstract

The invention discloses a screw type multi-component material batching device controller, which comprises an input module, a storage module, an output module and a processing module, wherein the processing module also comprises a prediction module, a weight monitoring module, an error calculation module and a logic control module. And iteratively updating the predicted value of the air volume based on the predicted value of the last air volume, the blanking error and the accumulated blanking error, and closing the screw conveyor according to the updated value. According to the invention, the material level of the blanking bin is controlled within a narrow range by adjusting the rotating speed of the feeding pump, the running speed of the screw conveyor is adjusted, the change of material distribution in the blanking process is reduced by the vibrating rod based on the detection of the distance sensor and the weighing module, and the stability of material compactness and blanking form is ensured, so that the iterative prediction convergence speed is accelerated, the precision is ensured, and meanwhile, a higher blanking speed is obtained, and the device is suitable for small-batch rapid batching.

Description

Screw type multi-component material batching device controller

The application is divisional application with application number 201710895901.5, application date 2017, 09 and 19, and invention name 'screw type multi-component material batching device and controller thereof'.

Technical Field

The invention relates to the field of quantitative batching, in particular to a screw type multi-component material batching device controller.

Background

In industrial and agricultural manufacturing and commodity packaging, a large amount of powder materials, such as polypropylene, polystyrene, polyvinyl chloride, light methyl cellulose, polyacrylonitrile, epoxy resin powder coating and other chemical raw materials, quartz sand, cement and other building raw materials, washing powder and other daily chemical products, millet, soybean and other grain and bean agricultural products, or powder, slag and granular processed food, feed, chemical fertilizer, pesticide and other agricultural production materials, as well as powder and granular health care products, Chinese and Western medicaments, seasonings and the like need to be automatically quantitatively packaged or prepared by batching.

At present, many enterprises in China still adopt manual quantitative batching or packaging, so that on one hand, the labor intensity is high, the speed is low, and the economic benefit is poor; on the other hand, manual quantification of food, medicine and the like often cannot meet the sanitary requirements, toxic and harmful materials are used, and manual quantification is easy to cause harm to human bodies. Therefore, for the production enterprises, it is urgently needed to provide a multi-component automatic quantitative blanking dosing device or device with lower cost and higher rate and accuracy, and meet the requirements of quantitative packaging of a large amount of materials or dosing manufacturing.

At present, two common methods, namely a positive displacement type and a weighing type, are adopted for automatic quantitative powder material feeding devices at home and abroad. The volumetric quantification is used for metering filling or feeding according to the volume of the material, the quantitative feeding is rapid, but the quality of the quantified material is changed by the change of the density of the material. In order to improve the blanking precision, various adjusting methods are provided, for example, in the chinese patent with application number 201320001933.3, the variable frequency speed regulation is adopted for the screw, the feeding speed is gradually reduced when the target value is approached, and the air drop value is reduced; in the Chinese patent with the application number of 201310234280.8, a large screw and a small screw are adopted in a three-speed variable-frequency feeding process of a soda packing machine for feeding materials in multiple stages; the Chinese patent with the application number of 200920248298.2 reduces the influence of the fall of the feeding by a method of first quick and then slow considering that the quantitative control is difficult to control when the fast feeding is carried out; the final blanking value of the non-weighing schemes can only be close to the expected value, and the accuracy is not high.

The weighing type quantitative feeding method is characterized in that the weighing type quantitative feeding method is used for metering, filling or feeding according to the set once amount of the material, the material needs to be weighed continuously in the feeding process, the feeding amount is controlled in a feedback mode according to the weighing result, and due to the fact that the weighing is greatly influenced by feeding impact and air lag materials, the feeding speed and the feeding precision face a lot of difficulties. In order to compensate the interference of the materials in the air to the metering precision, a technology of closing a valve in advance is adopted in many schemes, for example, a Chinese patent with the application number of 201410230888.8 divides a material proportioning and weighing process into three stages, and an iterative learning control mode is adopted in the last stage to calculate the closing advanced control quantity, but the scheme can only improve the blanking precision after the learning is finished, and the accumulated blanking precision in the learning process cannot be guaranteed.

Disclosure of Invention

The simple screw type feeder belongs to the volumetric quantitative category, the volumetric quantitative filling is based on the volume to measure the quantity of the filled materials, the structure is simple, the cost is low, but the stability and the precision of the quantitative filling speed depend on the stability of the materials according to the specific gravity, and the influence of material properties such as material loosening degree, particle uniformity degree and hygroscopicity is large.

In principle, volumetric dosing filling can now be divided into two types, controlling the flow rate or time of the filling material and dosing the material with the same dosing container. The former method usually adopts the method of controlling the vibration time of a vibrating feeder or controlling the rotation time of a spiral filling machine to realize quantitative filling; the latter is a quantitative filling machine of a measuring cup, a measuring cylinder or a plunger, and the like; both types have a common problem in that the apparent specific gravity of the material is as stable as possible.

Since the ordinary positive displacement type is conversion type in nature and cannot grasp the exact quality of the blanking like a weighing type, although a scheme combining weighing is provided later, the precision can be ensured only by depending on the extremely low feeding speed at the final stage of the blanking because no empty space amount prediction exists.

Therefore, the invention combines dynamic weighing detection with a screw feeder, improves a discharging bin and a weighing hopper of a discharging device, reduces the change of compactness in the material bin and the air fall of materials, and dynamically adjusts the stop time of a screw conveyor and the operation speed of the last stage in the discharging process by taking the current error and the accumulated error as controlled quantities in iterative prediction, thereby obtaining higher average operation speed while ensuring the precision and avoiding the problem that the general screw type discharging device operates particularly slowly in the last stage.

The technical scheme of the invention is that a screw type multi-component material batching device with the following structure is provided: the device comprises a frame, a blanking bin, a spiral conveyor, a measuring hopper, a weighing module, a blanking valve, a mixing hopper, a controller, a storage bin and a feeding pump;

the spiral conveyor is positioned below the blanking bin, the blanking bin and the spiral conveyor are 2-6 groups,

the weighing hopper is arranged below the spiral conveyor and is arranged on a weighing module fixed on the frame, and the bottom opening of the weighing hopper is controlled by a blanking valve; a distributor is arranged at the upper part of the metering hopper;

the mixing hopper is positioned below the blanking valve, and the bottom of the mixing hopper is provided with a push plate;

the controller controls the rotating speed of the feeding pump to enable the material level of the discharging bin to be within a preset range, and controls the opening time and the operating speed of each screw conveyor and reads the sensing data of the weighing module to respectively perform discharging calibration on the materials of each component; iteratively predicting the blanking empty space amount of the spiral conveyor, and adjusting the closing time of the spiral conveyor based on the comparison of the accumulated blanking amount and formula data; the controller controls the screw conveyors to act in sequence, after the formula amount blanking is finished, the blanking valve is opened, then the push plate is opened after the materials in the mixing hopper are detected to be accumulated to a set value, and the uniformly mixed materials are discharged.

Preferably, the feeding pump is a screw type feeding pump, a material spray head is arranged at the outlet of the feeding pipe at the rear end of the feeding pump, the material spray head is in a spherical cap shape, and round small holes are distributed on the surface of the material spray head.

Preferably, the rotational speed of the feed pump is controlled according to the following formula:

wherein, V_{0 feeding}A set maximum feeding speed, L is the current material level of the feed bin, L_MAnd L_mRespectively the preset highest and lowest feeding bin material positions.

Preferably, a distance sensor is arranged on a top angle of the discharging bin close to the center of the rack, and the distance sensor is provided with a rotating base.

Preferably, the distributor is in a cone structure with a cone-shaped upper part and a flattened lower part, the upper part of the distributor is in an opening shape, and the lower part of the distributor is only provided with slope-shaped nozzles at two ends in the length direction; the measuring hopper is provided with staggered spherical crown-shaped distributing bulges in the direction facing the nozzle.

Preferably, the frame is close to feed bin lateral wall department and installs the vibrating arm, the vibrating arm is including consecutive pillar, cloud platform, vibrator, the pole that shakes, there is spring damper vibrator bottom the vibrator, it has the granule arch to shake pole surface distribution.

Preferably, the bottom of the blanking bin is provided with a drawing plate; the screw conveyor comprises a screw box, a conveying screw, a connector and a motor, wherein a motor shell is connected with the screw box through the connector, the conveying screw in the screw box is connected with a motor shaft through a shaft sleeve, a feeding hole is formed in the upper surface of the screw box relative to the opening at the bottom of the discharging bin, and the other end, opposite to the motor, of the screw box is further connected with a vertically-placed discharging pipe.

Preferably, a material level sensor is installed on the side wall of the mixing hopper, a mixer is further arranged in the mixing hopper, the mixer adopts a spiral blade stirrer, and a material conveying pipe is further arranged below the push plate.

Preferably, the controller predicts the blanking air space amount by using the following formula:

Wa_k+1＝Wa_k+(α·e_k+β·E_k)，

wherein, Wa_kAnd Wa_k+1Respectively, two successive predicted values of the amount of air space, e_kAnd E_kThe feeding error at the k-th time and the cumulative feeding error are respectively, and α and β are respectively coefficients of the section (0, 1) and have α + β equal to 1.

Preferably, the controller controls the operating speed of the screw conveyor in the following manner:

A. from a stopped state at a rate of mu a_maxStarting at acceleration, when the speed reaches lambda.v_RKeeping the speed unchanged;

B. when the closing time is up, the value is expressed in mu a_maxThe acceleration starts to decelerate until stopping;

wherein, a_maxRated maximum acceleration, v, of the screw conveyor_RThe maximum speed is mu is an acceleration coefficient between 0.5 and 0.9, and the lambda is a speed coefficient between 0.85 and 1.0;

the closing time refers to the blanking time read from the weighing moduleThe weight is equal to:

wherein Ws and Wa are respectively the predicted values of the current one-time material discharge amount and the empty space amount, d is the discharge rate of the screw conveyer when the screw rotates at the maximum speed, and t is the discharge rate of the screw conveyer when the screw rotates at the maximum speed_sFor the deceleration stop time length: t is t_s＝λ·v_R/μ·a_max。

The other technical scheme of the invention is that a screw type multi-component material batching device controller is provided, which comprises an input module, a storage module, an output module and a processing module, wherein the processing module comprises a prediction module, a weight monitoring module, an error calculation module and a logic control module;

the input module receives the touch screen operation instruction and reads the sensing data of the weighing module,

the storage module is used for storing configuration data and processing procedure data,

the weight monitoring module compares the real-time weight value obtained by the input module with the target weight value compensated by the empty space predicted value and closes the screw conveyor below the blanking bin through the output module when the two weight values are equal,

the error calculation module calculates and updates the blanking error and the accumulated blanking error,

the prediction module carries out iterative update on the predicted value of the air quantity according to the predicted value of the last air quantity, the feeding error and the accumulated feeding error,

the logic control module controls the actions of the screw conveyors, the blanking valve at the bottom of the measuring hopper and the vibrating rod in the blanking bin in turn, and the ingredients are prepared according to the formula.

Compared with the prior art, the structure of the invention has the following advantages: according to the invention, the distance sensor and the rotatable vibrating rod are respectively adopted to detect and adjust the material accumulation form in the discharging bin, so that the stability of material compactness is ensured; the change of the air fall and the impact quantity of the material is reduced by arranging the material distributor in the weighing hopper, so that the convergence speed of iterative prediction can be accelerated; in the iterative prediction of the air quantity, the blanking accumulated error is controlled, so that the blanking in the learning process can be effectively utilized, and the material waste is avoided; meanwhile, due to the convergence of iterative prediction, the screw can keep a higher running speed in the blanking process, and the blanking efficiency is improved.

Drawings

FIG. 1 is a composition structure diagram of a screw type multi-component material batching device;

FIG. 2 is a structural diagram of the screw type multicomponent material batching device;

FIG. 3 is a schematic view of a material falling process;

FIG. 4 is a schematic view of a partial structure of a storage silo and a feed silo;

FIG. 5 is a schematic view of the material level in the feed bin;

FIG. 6 is a schematic view of distribution detection of materials in a blanking bin;

FIG. 7 is a schematic view of a vibrating rod structure and a moving track;

FIG. 8 is a schematic view of the side wall structure of the distributor and the weighing hopper;

FIG. 9 is a motor speed regulation curve;

FIG. 10 is a schematic view of the layering of a multi-component material in a weighing hopper;

FIG. 11 is a graph showing the change in weight during the falling of a material;

FIG. 12 is a statistical chart of errors in a material iterative prediction blanking process;

FIG. 13 is a block diagram of the controller of the screw type multi-component material batching device.

Wherein: 1. the device comprises a discharging bin 2, a screw conveyor 3, a metering hopper 4, a weighing module 5, a discharging valve 6, a mixing hopper 7, a push plate 8, a conveying pipe 9, a controller 10, a storage bin 11, a feeding pump 12, a vibrating rod 13, a mixer 14, a material level sensor 15, a feeding pipe 16, a material spray head 17, a small hole 18, a distance sensor base 19, a distance sensor 20, a material level surface 21, a stopping pointing point 22, a scanning line 23, a distributor 24, a distributor nozzle 25, a distributing bulge 26 and a discharging pipe

30. Rack

91. Input module 92, processing module 93, storage module 94, output module 95, weight monitoring module 96, logic control module 97, prediction module 98, error calculation module

101. Drawing plate

121. Pillar 122, cradle head 123, vibrator 124, vibration rod 125, particle projection 126, vibration rod orbit

201. Screw box 202, conveying screw 203, connector 204 and motor

Detailed Description

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, but the present invention is not limited to only these embodiments. The invention is intended to cover alternatives, modifications, equivalents and alternatives which may be included within the spirit and scope of the invention.

In the following description of the preferred embodiments of the present invention, specific details are set forth in order to provide a thorough understanding of the present invention, and it will be apparent to those skilled in the art that the present invention may be practiced without these specific details.

The invention is described in more detail in the following paragraphs by way of example with reference to the accompanying drawings. It should be noted that the drawings are in simplified form and are not to precise scale, which is only used for convenience and clarity to assist in describing the embodiments of the present invention.

As shown in fig. 1 and 2, the screw type multi-component material batching device comprises a discharging bin 1, a screw conveyor 2, a metering hopper 3, a weighing module 4, a discharging valve 5, a mixing hopper 6 and a controller 9, wherein each component material comprises a group of discharging bins 1 corresponding to the screw conveyor 2, the types of the commonly used components are 2-6, and the types of the components can be increased according to requirements. Preferably, the blanking bin 1 is of a bin-shaped structure consisting of a right trapezoid and a rectangle, and the blanking bin and the spiral conveyor are 2-6 groups.

The bottom of the blanking bin 1 is provided with a drawing plate 101, the drawing plate is opened during blanking, and the material flows out from an opening at the bottom of the blanking bin.

The screw conveyor 2 comprises a screw box 201, a conveying screw 202, a connector 203 and a motor 204, wherein the shell of the motor 204 is connected with the screw box 201 through the connector 203, and the conveying screw 202 in the screw box 201 is connected with the shaft of the motor 204 through a shaft sleeve; the upper surface of the screw box 201 is provided with a feeding hole corresponding to the bottom opening of the discharging bin 1, the other end of the screw box opposite to the motor is connected to a discharging pipe 26, and the discharging pipe 26 is fixed on the frame 30.

Preferably, the inner wall of the blanking pipe 26 can be provided with a spiral groove, and the wall of the spiral groove is discontinuously distributed at the tail section close to the bottom of the blanking pipe.

Preferably, a part consisting of two truncated cones, the tops of which are opposite and the bottom of which is provided with a shower nozzle, can be arranged in the blanking pipe 26, so that the materials fall uniformly.

As shown in fig. 1 and 2, when discharging, the controller 9 opens the drawing plate 101, the material falls from the discharging bin 1 into the screw box 201 of the screw conveyor 2, the controller 9 commands the motor 204 to start, the conveying screw 202 rotates along with the motor, and the material is conveyed to the end discharging pipe 26 and falls from the discharging pipe 26 into the weighing hopper 3 below.

The housing 30 serves as a frame of the apparatus for fixing and supporting the other respective components. The weighing module 4 is fixed on the frame 30, the weighing hopper 3 is movably buckled and pressed on the weighing module 4, the bottom of the weighing hopper 3 is provided with an opening, and the opening and the closing of the opening are controlled by the blanking valve 5. The weighing hopper 4 is located at the lower part of the blanking pipe 26, and a plurality of screw conveyors 2 are distributed in a radial direction relative to the centers of the blanking pipe 26 and the weighing hopper 4.

As shown in fig. 1 and 13, the controller 9 includes an input module 91, a storage module 93, an output module 94, and a processing module 92, wherein the processing module 92 includes a prediction module 97, a weight monitoring module 95, an error calculation module 98, and a logic control module 96.

The input module 91 receives an operation instruction and reads sensing data of a weighing module, a distance sensor and the like through a touch screen, the storage module 93 is used for storing configuration data and processing process data, the weight monitoring module 95 compares a real-time weight value obtained by the input module 91 with a target weight value compensated by an empty quantity predicted value and closes the spiral conveyor 2 below the lower bin 1 through the output module 94 when the two weight values are equal, the error calculation module 98 calculates and updates the blanking error and the accumulated blanking error at the time, the prediction module 97 iteratively updates the empty quantity predicted value according to the last empty quantity predicted value, the blanking error and the accumulated blanking error, the logic control module 98 controls the spiral conveyors 2, a blanking valve at the bottom of the weighing hopper and other action parts including action operation of a vibrating rod in the lower bin, a push plate in the mixing hopper, a feeding pump and the like in turn, the ingredients are prepared according to the formula.

The controller 9 adopts a touch type operation mode, a human-computer interface is arranged on a touch screen of the controller for setting the formula of the multi-component material and other parameters, and the formula comprises the total weight of one-time blanking and the percentage of each component in the weight. The controller 9 dynamically reads the current reading of the weighing module 4, and the blanking and the batching according to the formula are realized by controlling each action part.

The mixing hopper 6 is located below the blanking valve 5 and has a push plate 7 at its bottom, below which a feed pipe 8 is connected, which feeds the multicomponent mixture to a packaging bag or a production facility.

Preferably, a level sensor 14 is arranged on the side wall of the mixing hopper 6, and a mixer 13 is arranged inside the level sensor, wherein the mixer 13 adopts a spiral blade stirrer. The capacity of the mixing hopper 6 is 15 times of that of the weighing hopper 3, after a plurality of one-time baiting is completed, the controller 9 reads the state of the material level sensor 14, if the material level is detected to exceed a set threshold value, the mixer is controlled to rotate and stir, after a plurality of materials are uniformly mixed, under the control of the controller 9, the push plate 7 is opened, and the mixed materials are output from the material conveying pipe 8.

FIG. 3 is a diagram illustrating the change of impact of level drop and falling speed on a weighing hopper during the falling of a material at an initial speed v₀Falling from the screw conveyor 2, the distance between the outlet of the screw conveyor 2 and the bottom of the measuring hopper 3 is H, and the distance is along with the material level H in the measuring hopper₂Increase of (2), air drop h₁It will be smaller.

The mass equivalent change of the material detected by the weighing module can be represented by the following formula:

wherein dm is the blanking mass (g/s) per unit time at the outlet of the screw conveyor 2 at the time t, v₀The initial velocity of the material as it falls, the velocity of the material at Δ m as it falls into the weighing hopper, is determined from the velocity v over the time Δ t₁Becomes 0.

As can be seen from the formula (1), the air fall h is followed₁The impact of the material on the weighing hopper also changes, so that the weight change of the weighing hopper changes with time.

On the other hand, the blanking mass equivalent per unit time in the formula (1) is also influenced by the shape distribution of the materials in the blanking bin 1.

The invention discloses a simple screw type feeder, which belongs to the volumetric quantitative category, and the method adopts dynamic weighing to detect the falling amount of a material and predicts the empty amount of the material through iterative learning. In order to reduce the change of the falling rate of the material during the conveying of the screw, accelerate the learning convergence rate and inhibit the fluctuation range of the control quantity, the invention adopts a distance sensor and a rotatable vibrating rod to detect and adjust the material accumulation form in the lower storage bin, so that the dynamic material arch is alternately formed and collapsed above the lower opening of the lower storage bin, and the material compactness and the stability of the blanking form are ensured.

As shown in FIG. 4, the discharging bin 1 continuously discharges materials, and when the material level in the bin is reduced to a certain value, the materials need to be supplemented. For this purpose, a storage bin 10 is arranged above the lower bin 1, and the material in the storage bin 10 is fed into the lower bin 1 through a feed pump 11 and a feed pipe 15. In order to make the material particles fall evenly, a material spray nozzle 16 is arranged at the outlet of the tail end of the feeding pipe 15, the surface of the material spray nozzle 16 is in a spherical shape, round small holes 17 are distributed on the surface of the material spray nozzle, and the aperture of the small holes is optimized according to the granularity of the material. The feed pump 11 is a screw-type feed pump, and its operation is controlled by a controller.

As shown in FIG. 5, the feeding pump 11 is controlled by the controller to maintain the level of the top surface of the material in the discharging bin at a preset value L_TThe rotation speed is controlled by the following formula:

wherein, V_{0 feeding}A set maximum feeding speed, L is the current material level of the feed bin, L_MAnd L_mAre respectively preset at L_TThe highest and lowest levels nearby.

As shown in the combined drawings of FIGS. 6 and 7, the invention greatly weakens the compaction force effect generated by the loading impact by the detection and action coordination of the distance sensor and the vibrating rod, effectively prevents the granularity segregation of the materials in the bin, activates the materials in the lower bin and ensures the uniform distribution of the materials.

Two pictures of controlling in fig. 6 are observed from side view and overlooking direction of feed bin 1 respectively, as shown in fig. 6, install distance sensor 19 on a apex angle of feed bin 1 nearly frame center, distance sensor 19 has a distance sensor base 18, and this base can be every single move and rotatory for distance sensor can stop the direction of directive point 21 at the difference and carry out material detection, and each stops directive point 21 and constitutes scanning line 22 that is close the concentric circle, thereby judges the distribution of ejection of compact level 20.

As shown in fig. 7, the present invention improves the distribution of the material by the action of the vibration rod 12 in the lower bin 1. The vibrating rod 12 is fixed on the frame 30, and includes a support column 121, a holder 122, a vibrator 123, and a vibrating rod 124 connected in sequence, a spring buffer is arranged at the bottom of the vibrator 123, particle protrusions 125 are distributed on the surface of the vibrating rod 124, and the holder 122 can pitch and rotate, so that the vibrating rod 124 makes a curvilinear motion in the lower bunker 1.

In the blanking process, the distribution of the materials in the blanking bin is judged by respectively detecting the distance sensor and tracking the blanking rate in unit time, so that the material level in the blanking bin keeps an approximate parabolic shape. As shown in fig. 6 and 7, when the materials are uniformly distributed, the distance values of the materials detected by the distance sensors in different directions are approximately concentrated in a smaller range after geometric transformation of an included angle between the ray and the vertical direction. When the material is locally hardened or is arched stably, the detected distance value exceeds the range. Meanwhile, the feeding speed of each feeding bin is tracked in real time through the weighing module. When the distance sensor detects the abnormal state or finds that the fluctuation of the blanking amount in unit time exceeds a set threshold value, such as 5%, the controller commands the vibrating rod to act, the vibrating rod starts to pass through a high-point area of the material level to a low-point area of the material level from a starting point through the operation of the pan-tilt head to perform snake-shaped stirring, and a vibrating rod track 126 of the tail end of the vibrating rod 124 in the blanking bin 1 is shown in fig. 7; meanwhile, the vibrator starts to vibrate, and the particle protrusions on the vibration rod drive peripheral particles, so that hardening or material arch which is occasionally formed is broken, and the material distribution is recovered to be uniform. Through dynamic detection and control of material distribution, fluctuation of material compactness is reduced, and therefore stability of filling amount in unit time is guaranteed. And (5) stopping feeding while the vibrating rod acts, and closing the drawing plate.

Referring to FIGS. 3 and 8, it can be seen from the formula (1) that the material falls in the air h₁The impact of the material on the weighing hopper is changed, so that the weight increase value of the weighing module in unit time is changed. As shown in FIG. 8, in order to reduce the influence of the change of the air fall, the invention arranges a distributor 23 on the upper part of the weighing hopper 3, and the distributor 23 is an hourglass-shaped distributor with the upper part being a cone and the lower part being a flattened cone structure; wherein the upper part is in an opening shape and receives the materials in the blanking bin; the lower part is symmetrically provided with ramp-shaped nozzles 24 only at both ends in the length direction. The measuring hopper 3 is distributed with staggered spherical crown-shaped distributing bulges 25 facing the direction of the nozzle 24, and preferably, the diameter of the distributing bulges is 0.2-0.6 mm or 2-3 times of the diameter of the fallen materials.

Through the action of the distributor, the falling of the materials is divided into three stages, wherein the first stage is from an opening at the bottom of the blanking bin to the blanking pipe through the screw conveyor, the second stage is from the blanking pipe to the distributor, and the third stage is from the nozzle of the distributor to the material pile in the weighing hopper. In the third stage, due to the action of the material distributor and the distributing bulges distributed on the wall of the measuring hopper in a staggered manner, the speed of impacting the material surface in the measuring hopper by material particles is greatly reduced, and the difference of impact forces from the nozzle of the material distributor to the material pile surfaces with different heights in the measuring hopper is very small, so that conditions are provided for iterative prediction of the controller.

Based on iterative learning, the controller dynamically predicts the empty space amount of falling materials, and the blanking control steps are as follows in combination with the steps shown in fig. 9:

(1) determining the primary blanking amount Ws of each component according to the primary amount and the proportion of each formula, and assigning an initial value 0 to the accumulated blanking error E of each component; setting the current component as a first component;

(2) feeding the current component, reading the sensor value of the weighing module by the controller, recording the initial weight G0 of the weighing hopper, starting the screw conveyer and feeding the weighing hopper with mu a_maxAcceleration, when the speed reaches v_H＝λ·v_RKeeping the speed unchanged;

(3) when the weight of the measuring hopper is detected to reach (G0+ Ws-Wa-0.5. lambda. d. t)_s) At the beginning, the screw conveyor is closed and the speed is controlled to be mu a_maxThe acceleration starts to decelerate until stopping;

wherein d is the discharge rate of the screw conveyor when the screw is running at maximum speed, t_sIs from the moment of starting deceleration t₂Time t from start to stop₃Length of time between: t is t_s＝λ·v_R/μ·a_max；

(4) Waiting for the materials to completely fall to the weighing hopper, reading a sensing value of the weighing module, obtaining the current actual blanking amount Wr, and calculating the blanking error e to be Wr-Ws;

(5) updating the accumulated blanking error E ' ═ E + E, and calculating an empty space predicted value Wa ' ═ Wa + (alpha E + beta E '), wherein alpha and beta are respectively iteration coefficients of an interval (0, 1) and alpha + beta is 1;

(6) iteration, namely E is equal to E ', Wa is equal to Wa', and preparation is carried out for next blanking;

(7) replacing the blanking components, if the blanking of all the components is finished, turning to the next step, otherwise, turning to the step 2;

(8) opening a blanking valve to enable the materials with the primary formula amount consisting of the multi-component materials to fall into a mixing hopper, reading the state of a material level sensor, controlling a mixer to rotate and stir if the detected material level exceeds a set threshold value, opening a push plate after uniformly mixing the multi-component materials, and outputting the mixed materials from a material conveying pipe;

(9) if the preset blanking batch is finished, finishing blanking; otherwise, the component is set as the first component, and step 2 is carried out.

During the unloading, the controller still carries out real-time detection to the material pile form in the unloading storehouse through the computational analysis to distance sensor and weighing module signal, if discover abnormal unloading, then in time order rotatable vibrating arm action, whole evenly distributed when the guarantee unloading.

Before continuous blanking, the following operations are carried out:

(i) calibrating the weighing module and the distance sensor through an off-line experiment;

(ii) setting parameters including a time length Tb and the repetition times of calibration of a primary quantity, a formula table, a batch value, a blanking rate and a stable weighing delay Td through a touch screen of a controller;

(iii) carrying out blanking calibration on the components: starting to operate the screw conveyor for a certain time Tb according to or by referring to a speed regulation curve shown in FIG. 9 from the time 0, and respectively reading and recording the weight values Wcb and Wdb of the weighing modules at the time of closing the screw conveyor Tb and the time of Tb + Td after weighing is stable; repeating the steps for several times, calculating the blanking rate d ═ AVG [ Wdb/(Tb-t)_s)]And/λ, the initial value Wa of the air volume is AVG (Wdb-Wcb).

The device of the invention is used for blanking, and the blanking results are shown in figures 10-12. Fig. 10 is a schematic view showing distribution of materials in a measuring hopper during discharging of 4 components. Fig. 11 is a graph of the change in the weighing module reading during a 900ms long material fall, with the abscissa being the delay time after the screw conveyor is turned off. It can be seen that due to the impact force, the weighing reading will overshoot, and then return to the actual weight; and, the material in the air only falls into the weighing hopper completely after the screw conveyor is closed for about 700ms, and the reading of the weighing module tends to be stable.

Fig. 12 is a statistic of the blanking errors of the single-component materials in the blanking process of the device, and it can be seen from the figure that, because the factors of the accumulated errors are considered in the iterative prediction, the blanking errors can approach to 0, and the accumulated errors gradually converge after several iterations. Therefore, compared with other iterative learning, the device does not need to discard materials in the iterative learning process, but can be directly applied to subsequent production, so that the device is suitable for small-batch quick batching and blanking.

The above-described embodiments do not limit the scope of the present invention. Any modification, equivalent replacement, and improvement made within the spirit and principle of the above-described embodiments should be included in the protection scope of the technical solution.

Claims

1. The screw type multi-component material batching device controller comprises an input module, a storage module, an output module and a processing module, wherein the processing module comprises a prediction module, a weight monitoring module, an error calculation module and a logic control module;

the prediction module carries out iterative update on the air quantity predicted value according to the last air quantity predicted value, the blanking error E and the accumulated blanking error E': wa ═ Wa + (α E + β E'), where α and β are iteration coefficients of the interval (0, 1) and α + β ═ 1,

the logic control module controls the screw conveyors to act in a wheel flow mode, and the ingredients are prepared according to the formula.

2. The screw multi-component material batching device controller according to claim 1, wherein the logic control module controls the blanking valve at the bottom of the weighing hopper to open after one batch of formula amount blanking is completed.

3. The screw multi-component material batching device controller according to claim 1, wherein after detecting the material accumulation in the mixing hopper to a set value, the controller controls the push plate at the bottom of the mixing hopper to open and discharge the uniformly mixed material.

4. The screw multi-component material batching device controller according to claim 1, wherein said controller commands the vibrating rod to move when the distance value of the material detected by the distance sensor in different directions exceeds a set range after geometric transformation of the angle between the ray and the vertical direction.

5. The screw multi-component material dispensing device controller of claim 1, wherein the controller commands the vibratory rod to move when the fluctuation of the discharge per unit time is found to exceed a set threshold.

6. The screw multi-component material batching device controller according to claim 1, wherein after detecting that the material level of the mixing hopper exceeds a set threshold value, the controller controls the mixer to rotate and stir so as to uniformly mix a plurality of materials.

7. The screw multi-component material batching device controller according to claim 6, wherein said controller further controls the push plate to open for discharging the homogeneously mixed material.

8. The screw multi-component material batching device controller according to claim 1, wherein said controller controls the feed pump rotational speed such that the level of the lower bin is within a preset range, said feed pump rotational speed being controlled according to the following formula:

9. The screw multi-component material batching device controller according to claim 1, wherein said controller controls the operating speed of the screw conveyor as follows:

the closing time means that the current baiting weight read from the weighing module is equal to: