An automatic control method for the filling rate of a mixer and a mixer

Abstract

This application relates to the technical field of automatic control of the filling rate of a mixer, and specifically relates to a method and a mixer for automatically controlling the filling rate of a mixer. The method includes: determining the filling distribution coefficient of the mixer at the current moment based on the degree of dispersion of all the rotational speed data of the mixer in the last period, as well as the degree of dispersion and the average distribution of all the rotational speed data of the mixer within a preset duration, and determining the filling rate offset coefficient of the mixer at the current moment in combination with the filling rate difference coefficient; obtaining the filling mass and filling volume of the mixed material in the mixer multiple times, and controlling the mixed material in the mixer in combination with the filling rate offset coefficient. This application improves the accuracy of adjusting the filling rate of the mixer by monitoring the real-time data changes during the operation of the mixer.

Description

Technical Field

[0001] This application relates to the technical field of automatic control of the filling rate of a mixer, and particularly relates to an automatic control method for the filling rate of a mixer and a mixer. Background Art

[0002] With the continuous advancement of the industrialization process, plastic products occupy an important position in many industries due to their excellent performance and wide range of uses. Polyvinyl chloride (PVC), as a commonly used plastic material, is widely used in multiple fields such as construction, packaging, and automobiles. The production process of PVC mainly includes links such as mixing of raw materials, plasticization, and molding. Among them, the mixing process is a key step to ensure the quality and performance of PVC products. During the mixing process, the uniformity of the mixed materials directly affects the quality of the final product. Therefore, how to achieve efficient and uniform mixing of PVC has become an important topic for improving production efficiency and product quality.

[0003] Currently, when using a mixer to mix raw materials, the filling rate of the mixer is one of the main factors affecting the mixing effect, and the control of the filling rate of the mixer still faces many challenges. Existing automatic control methods for the filling rate often set a filling rate threshold range based on experience. When mixing raw materials in different batches, they often rely on a single parameter (such as weight or volume) to control the filling rate. However, this method has poor adaptability to changes in the density of the mixed materials. The raw materials in different batches may not be exactly the same, resulting in large differences in the density of the mixed materials in different batches. However, setting a fixed filling rate threshold range lacks relatively accurate consideration of this density difference, reducing the accuracy of adjusting the filling rate of the mixer. Summary of the Invention

[0004] To solve the above technical problems, the purpose of this application is to provide an automatic control method for the filling rate of a mixer and a mixer, and the specific technical solutions adopted are as follows:

[0005] In a first aspect, an embodiment of this application provides an automatic control method for the filling rate of a mixer, and the method includes the following steps:

[0006] Obtain the rotational speed data of all acquisition moments of the mixer within a preset time period before the current moment, and the vibration data of all acquisition moments in each direction of the mixer;

[0007] Divide the preset time period into multiple time segments, and based on the degree of dispersion of all vibration data in each direction of the mixer within each time segment, determine the vibration metric value of the mixer at the current moment; based on the difference between all vibration data between any two directions of the mixer within each time segment, determine the difference degree of the mixer within each time segment, and combine the vibration metric value to determine the filling rate difference coefficient of the mixer at the current moment;

[0008] Determine the filling distribution coefficient of the mixer at the current moment based on the degree of dispersion of all rotational speed data of the mixer in the last period before the current moment, as well as the degree of dispersion and average distribution of all rotational speed data of the mixer within a preset duration, and determine the filling rate offset coefficient of the mixer at the current moment in combination with the filling rate difference coefficient;

[0009] Obtain the filling mass and filling volume of the mixed material in the mixer multiple times, and determine the first and second fitting functions of the mixer in combination with the filling rate offset coefficient; based on the first and second fitting functions and the filling rate offset coefficient, determine the filling mass adjustment amount of the mixer at the current moment, and control the mixed material in the mixer.

[0010] Preferably, the method for determining the vibration measurement value of the mixer at the current moment is as follows:

[0011] Calculate the variance of all vibration data in each direction of the mixer in each period, and fit the variances of the vibration data in all periods in each direction of the mixer to obtain the fitting straight line in each direction of the mixer;

[0012] The vibration measurement value of the mixer at the current moment is the average level of the slopes of the fitting straight lines in all directions of the mixer.

[0013] Preferably, the method for determining the difference degree of the mixer in each period is as follows:

[0014] Calculate the difference between all vibration data between any two directions of the mixer in each period, and record it as the difference value between any two direction combinations of the mixer in each period;

[0015] The difference degree of the mixer in each period is the average value of the difference values between all two-direction combinations of the mixer in each period.

[0016] Preferably, the expression of the filling rate difference coefficient of the mixer at the current moment is: ; where A represents the filling rate difference coefficient of the mixer at the current moment; represents the vibration measurement value of the mixer at the current moment; represents the difference degree of the mixer in the last period before the current moment; represents the difference degree of the mixer in the i-th period before the current moment; represents the difference degree of the mixer in the (i + 1)-th period before the current moment; n represents the number of all periods within the preset duration before the current moment.

[0017] Preferably, the method for determining the filling distribution coefficient of the mixer at the current moment is as follows:

[0018] Denote the degree of dispersion of all rotational speed data of the mixer within the last period before the current moment as the first degree of dispersion of the mixer at the current moment;

[0019] Denote the degree of dispersion of all rotational speed data of the mixer within a preset duration before the current moment as the second degree of dispersion of the mixer at the current moment;

[0020] Calculate the product of the average level of all rotational speed data of the mixer within a preset duration before the current moment and the second degree of dispersion, and take the ratio of the first degree of dispersion to the product as the filling distribution coefficient of the mixer at the current moment.

[0021] Preferably, the expression of the filling rate offset coefficient of the mixer at the current moment is: ; where represents the filling rate offset coefficient of the mixer at the current moment; represents the filling distribution coefficient of the mixer at the current moment; exp( ) represents the exponential function with the natural constant as the base.

[0022] Preferably, the method for determining the first and second fitting functions of the mixer at the current moment is:

[0023] When the types of components of the mixed material in the mixer are the same, record the different filling masses and corresponding filling volumes of the mixed material. Each time the filling mass and filling volume are collected, and according to the method for obtaining the filling rate offset coefficient of the mixer at the current moment, calculate the filling rate offset coefficient of the mixer for the corresponding collection;

[0024] Take the ratio of the filling mass and filling volume of the mixed material for each collection as the filling density of the mixed material for each collection;

[0025] Among all collections, obtain the minimum value of the filling rate offset coefficients for all collections corresponding to each filling density, and take the filling mass of the mixed material for the collection corresponding to the minimum value as the optimal filling mass for this filling density;

[0026] Take all filling densities and their respective optimal filling masses as the independent variable and dependent variable of the fitting algorithm respectively, and output the fitting function between the filling density and the optimal filling mass as the first fitting function;

[0027] When the filling mass of the mixed material in the mixer is the same, obtain the filling volumes of the mixed material when the types of the mixed material are different, and calculate the filling density;

[0028] Take the filling rate offset coefficients of the mixer for all collections and their respective filling densities as the independent variable and dependent variable of the fitting algorithm respectively, and output the fitting function between the filling rate offset coefficient and the filling density as the second fitting function.

[0029] Preferably, the expression of the filling mass adjustment amount of the mixer at the current moment is: ; In the formula, Indicates the filling mass adjustment amount of the mixer at the current moment; Indicates the filling rate deviation coefficient of the mixer at the current moment; represents the first fitting function of the mixer at the current moment; represents the second fitting function of the mixer at the current moment; M represents the preset filling quality.

[0030] Preferably, the controlling of the mixed material in the mixer comprises:

[0031] If the filling mass adjustment amount of the mixer at the current moment is a negative number, the discharge port of the mixer is opened to discharge the mixed material of the filling mass adjustment amount; if the filling mass adjustment amount of the mixer at the current moment is a positive number, the feed port of the mixer is opened to inject the mixed material of the filling mass adjustment amount.

[0032] In a second aspect, an embodiment of the present application further provides a mixer, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein when the processor executes the computer program, the steps of any one of the above-mentioned methods for automatically controlling the filling rate of a mixer are implemented.

[0033] This application has at least the following beneficial effects:

[0034] The present application divides the preset time into multiple time periods, and determines the vibration measurement value of the mixer at the current moment based on the discrete degree of all vibration data in each direction of the mixer in each time period; determines the difference degree of the mixer in each time period based on the difference of all vibration data between any two directions of the mixer in each time period, and determines the filling rate difference coefficient of the mixer at the current moment in combination with the vibration measurement value, which has the beneficial effect of enhancing the accuracy of judging the mixing uniformity of the mixed materials;

[0035] The present application determines the filling distribution coefficient of the mixer at the current moment based on the discrete degree of all the speed data of the mixer in the last period, and the discrete degree and average distribution of all the speed data of the mixer in the preset time, and determines the filling rate deviation coefficient of the mixer at the current moment in combination with the filling rate difference coefficient. The beneficial effect is that the accuracy of measuring the filling rate being too large or too small is improved, thereby improving the accuracy of the filling rate adjustment;

[0036] This application obtains the filling mass and filling volume of the mixed material in the mixer multiple times, and determines the first and second fitting functions of the mixer in combination with the filling rate offset coefficient; based on the first and second fitting functions and the filling rate offset coefficient, the filling mass adjustment amount of the mixer at the current moment is determined to control the mixed material in the mixer, and the beneficial effect is that the uniformity of the mixed material in the mixer is improved. This application improves the accuracy of the filling rate adjustment of the mixer by monitoring the data changes during the operation of the mixer in real time. Description of the Drawings

[0037] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0038] Figure 1 It is a flowchart of the steps of an automatic filling rate control method for a mixer provided by an embodiment of the present application;

[0039] Figure 2 It is a schematic diagram of the process of obtaining the filling distribution coefficient provided by an embodiment of the present application;

[0040] Figure 3 It is a schematic diagram of the process of extracting the filling rate offset coefficient provided by an embodiment of the present application;

[0041] Figure 4 It is a schematic diagram of the first fitting function provided by an embodiment of the present application;

[0042] Figure 5 It is a schematic diagram of the second fitting function provided by an embodiment of the present application. Detailed Embodiments

[0043] In order to further elaborate on the technical means and effects adopted by the present application to achieve the predetermined invention purpose, the following will, in combination with the drawings and preferred embodiments, elaborate in detail on the specific embodiments, structures, features and effects of an automatic filling rate control method for a mixer and a mixer proposed according to the present application. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs.

[0045] The following specifically describes a method for automatically controlling the filling rate of a mixer and a specific solution of the mixer provided by the present application in conjunction with the accompanying drawings.

[0046] Please refer to Figure 1 , which shows a flowchart of the steps of a method for automatically controlling the filling rate of a mixer provided by an embodiment of the present application. The method includes the following steps:

[0047] Step S1: Obtain the rotational speed data of all acquisition times of the mixer within a preset time period before the current time, and the vibration data of all acquisition times in each direction of the mixer.

[0048] When the mixer mixes materials, through the agitation of the agitator, the mixed materials will undergo three mixing methods: convection, diffusion, and shear within the entire mixer. At the same time, since the density of the mixed materials at each position in the mixer is different when they are not mixed evenly, when the mixed materials collide with the mixer housing during the mixing process, the vibration conditions of the housing are not completely the same. Therefore, vibration sensors are installed in different directions on the mixer housing to monitor the vibration changes in different directions.

[0049] In this embodiment, a rotary encoder is installed on the transmission shaft of the agitator to obtain the rotational speed data of all acquisition times of the mixer within a preset time period t before the current time; vibration sensors are installed on the upper, lower, left, and right four directions of the mixer housing to obtain the vibration data of all acquisition times in each direction of the mixer within a preset time period t before the current time, where the data sampling frequency is set to f.

[0050] It should be noted that the values of the preset time period t and the data sampling frequency f are both set artificially. In this embodiment, the value of the preset time period t is 30s, and the value of the data sampling frequency f is 100Hz. Implementers can also set them according to specific situations by themselves, and this embodiment does not make special restrictions.

[0051] Step S2: Divide the preset time period into multiple time segments, determine the vibration measurement value of the mixer at the current time based on the degree of dispersion of all vibration data in each direction of the mixer within each time segment; determine the difference degree of the mixer within each time segment based on the difference between all vibration data between any two directions of the mixer within each time segment, and combine the vibration measurement value to determine the filling rate difference coefficient of the mixer at the current time.

[0052] In the process of mixing raw materials using a mixer, the existing method is to first preset a filling rate range based on experience, then calculate the actual filling rate according to the parameters (such as weight or volume) of the raw materials in the current batch, and finally adjust the actual filling rate according to the size relationship between the filling rate and the preset filling rate range. This method has high requirements for the accuracy of the preset filling rate range. When there is an error in this range, subsequent judgments will all have a certain error; and this method does not monitor the mixing process, and there is a possibility that the final mixing effect is poor, affecting production efficiency and quality.

[0053] In fact, during the mixing process, the degree of uniformity of the mixed materials and the filling rate of the mixed materials in the mixer will affect the vibration condition of the mixer and the rotation speed of the agitator. Therefore, by analyzing the dispersion degree of all vibration data in each direction of the mixer within each time period, the vibration measurement value of the mixer is determined; based on the difference between all vibration data between any two directions of the mixer within each time period, the difference degree of the mixer within each time period is determined, and in combination with the vibration measurement value, the filling rate difference coefficient of the mixer is determined to more flexibly and accurately control the filling rate. Specifically:

[0054] (1) Divide the preset time period evenly into multiple time periods, and each time period contains the same number of vibration data;

[0055] It should be noted that in this embodiment, the value of the preset time period t is set to 30s, so the preset time period is divided into 10 segments, that is, the length of each time period is 3s. Since the data sampling frequency is 100Hz, each time period contains 300 vibration data.

[0056] (2) Further, calculate the variance of all vibration data in each direction of the mixer within each time period, and fit the variances of the vibration data in all directions of the mixer in all time periods to obtain the fitting straight lines in each direction of the mixer;

[0057] It should be noted that there are many commonly used linear fitting algorithms. In this embodiment, the linear least squares method is used to fit the variance of the vibration data. Implementers can also use other linear fitting methods such as linear regression. Regarding the selection of the linear fitting algorithm, this embodiment does not make special restrictions.

[0058] Among them, the linear least squares method is a well-known technology, and the process of obtaining the fitting straight line will not be elaborated here.

[0059] (3) Further, record the average level of the slopes of the fitting straight lines in all directions of the mixer as the vibration measurement value of the mixer at the current moment;

[0060] It should be noted that there are many methods to measure the average level of a set of data. In this embodiment, the average level of the slopes of the fitting lines in all directions of the mixer is measured by calculating the mean value of the slopes of the fitting lines in all directions of the mixer. Implementers can also use other methods to measure the average level of data, such as the geometric mean. Regarding the selection of methods for measuring the average level of a set of data, this embodiment does not make special restrictions.

[0061] (4) Calculate the differences of all vibration data between any two directions of the mixer within each time period, and record them as the difference values between any two-direction combinations of the mixer within each time period;

[0062] Denote the mean value of the difference values between all two-direction combinations of the mixer within each time period as the difference degree of the mixer within each time period;

[0063] It should be noted that there are many methods to measure the differences between data groups. In this embodiment, the differences of all vibration data between any two directions of the mixer within each time period are measured by calculating the Euclidean distance between any two directions of the mixer within each time period. Implementers can also use other methods to measure the differences between data groups, such as the Manhattan distance and the DTW distance. Regarding the selection of methods for measuring the differences between data groups, this embodiment does not make special restrictions.

[0064] Among them, the calculation process of the Euclidean distance is a well-known technology, and its specific calculation steps will not be elaborated here.

[0065] (5) Further, based on the vibration metric and the difference degree, determine the filling rate difference coefficient of the mixer, specifically: the filling rate difference coefficient of the mixer The expression is: ; In the formula, represents the vibration metric value of the mixer at the current moment; represents the difference degree of the mixer in the last time period before the current moment; represents the difference degree of the mixer in the time period i before the current moment; represents the difference degree of the mixer in the time period i + 1 before the current moment; n represents the number of all time periods within the preset duration before the current moment.

[0066] Furthermore, it can be understood from the filling rate difference coefficient of the mixer that when the filling rate of the mixer is relatively optimal, the mixing uniformity of the final mixed material is better, so that the fluctuations of the vibration data in all directions become smaller and smaller. That is, the variance of all the vibration data in each direction of the mixer within each time period is smaller. After fitting the variance, it can be seen that the change trend of the fitting line as a whole shows a downward trend. That is, the slope of the finally obtained fitting line is negative and small, and the difference between all the vibration data in different directions within the same time period is smaller. As the mixed material is mixed more and more uniformly, the difference degree decreases more and more with the increase of time. That is, the difference degree in the last time period is the smallest, and the ratio of the difference degree between the adjacent previous time period and the subsequent time period is greater than 1. Therefore, the obtained filling rate difference coefficient is smaller, indicating that the filling rate of the mixer is relatively optimal; on the contrary, when the filling rate is poor (too large or too small), since the mixing uniformity of the final mixed material is still poor, the filling rate difference coefficient is relatively large.

[0067] Step S3: Based on the degree of dispersion of all the rotation speed data of the mixer within the last time period before the current moment, as well as the degree of dispersion and the average distribution of all the rotation speed data of the mixer within the preset time period, determine the filling distribution coefficient of the mixer at the current moment, and combine the filling rate difference coefficient to determine the filling rate offset coefficient of the mixer at the current moment.

[0068] The filling rate difference coefficient can only measure whether the filling rate in the mixer is relatively optimal, but cannot determine whether the filling rate is too large or too small. Therefore, based only on the filling rate difference coefficient, the control of the filling rate of the mixer cannot be carried out. When the input power of the mixer remains unchanged, the filling rate of the mixer will affect the rotation speed of the agitator.

[0069] When the filling rate is small, since the activity space of the mixed material is large, the gap between the mixed materials is relatively large, and the frictional resistance between the mixed materials is relatively small. Therefore, under the action of the agitator, the movement of the mixed material is less restricted, and thus the resistance received by the agitator during rotation is also small; at the same time, since the mixed material is relatively sparse, under the action of the centrifugal force, the mixed material is more likely to move outward during the mixing process and is more easily affected by the density of the mixed material. For the above reasons, when the filling rate is small, the rotation speed of the agitator is easily affected by the density of the mixed material, and the rotation speed fluctuates relatively greatly due to the density difference of the mixed material during the mixing process of the mixed material.

[0070] When the filling rate is relatively large, the active space of the mixed materials is small, the gaps between the mixed materials are relatively small, the frictional force between the mixed materials is large, and under the action of the stirrer, the moving resistance of the mixed materials is relatively large. At the same time, it also makes the rotational resistance of the stirrer large. As a result, even if the densities of the mixed materials are different, the rotational speed of the stirrer will not change significantly. That is, during the mixing process of the mixed materials, due to the density difference of the mixed materials, the rotational speed fluctuation of the stirrer is relatively small.

[0071] Therefore, in order to improve the accuracy of adjusting the filling rate of the mixer, based on the degree of dispersion of all the rotational speed data of the mixer within the last period and the degree of dispersion and average distribution of all the rotational speed data of the mixer within a preset period, the filling distribution coefficient of the mixer at the current moment is determined, and in combination with the filling rate difference coefficient, the filling rate offset coefficient of the mixer at the current moment is determined. Specifically:

[0072] (1) Denote the degree of dispersion of all the rotational speed data of the mixer within the last period before the current moment as the first degree of dispersion of the mixer before the current moment;

[0073] (2) Further, denote the degree of dispersion of all the rotational speed data of the mixer within a preset period before the current moment as the second degree of dispersion of the mixer at the current moment;

[0074] (3) Calculate the product of the average level of all the rotational speed data of the mixer within a preset period before the current moment and the second degree of dispersion, and take the ratio of the first degree of dispersion to the product as the filling distribution coefficient of the mixer at the current moment.

[0075] It should be noted that there are many methods to measure the degree of dispersion of a set of data. In this embodiment, the variance of all the rotational speed data of the mixer within the last period before the current moment is calculated to measure the degree of dispersion of all the rotational speed data of the mixer within the last period before the current moment, and the variance of all the rotational speed data of the mixer within a preset period before the current moment is calculated to measure the degree of dispersion of all the rotational speed data of the mixer within the preset period. Implementers can also use other methods such as the coefficient of dispersion or standard deviation that can measure the degree of dispersion of this set of data. There is no special limitation on the selection of the method for measuring the degree of dispersion of a set of data in this embodiment.

[0076] In addition, it should be understood that there are many methods to measure the average level of a set of data. In this embodiment, the mean value of all the rotational speed data of the mixer within a preset period before the current moment is calculated to measure the average level of all the rotational speed data of the mixer. Implementers can also use other methods such as the geometric mean to measure the average level of data. There is no special limitation on the selection of the method for measuring the average level of a set of data in this embodiment.

[0077] Preferably, the schematic diagram of the process for obtaining the filling distribution coefficient provided in this embodiment is as Figure 2 shown.

[0078] Furthermore, according to the filling distribution coefficient of the mixer, it can be understood that when the filling rate is small, the rotation speed of the mixer agitator is large, that is, the average level of all rotation speed data of the mixer within the preset time period is larger; and the density of the mixed material has a greater influence on the rotation speed of the agitator. During the mixing process of the mixed material, the rotation speed of the agitator fluctuates greatly, and the second dispersion degree of the mixer is larger; at the same time, when the filling rate is small, the mixing uniformity of the final mixed material is poor, so that the rotation speed data in the last time period is still large, that is, the first dispersion degree of the mixer is larger; on the contrary, when the filling rate is large, the rotation speed of the mixer agitator is small, that is, the average level of all rotation speed data of the mixer within the preset time period is smaller; and the density of the mixed material has a smaller influence on the rotation speed of the agitator. During the mixing process of the mixed material, the rotation speed of the agitator fluctuates less, and the second dispersion degree of the mixer is smaller; at the same time, when the filling rate is large, the mixing uniformity of the final mixed material is good, so that the rotation speed data in the last time period is still small, that is, the first dispersion degree of the mixer is smaller.

[0079] (4) Furthermore, based on the filling rate difference coefficient and the filling distribution coefficient, determine the filling rate offset coefficient of the mixer, specifically:

[0080] The expression of the filling rate offset coefficient B of the mixer is: ; in the formula, represents the filling distribution coefficient of the mixer; exp( ) represents the exponential function with the natural constant as the base.

[0081] Furthermore, according to the filling rate offset coefficient of the mixer, it can be understood that because when the filling rate is large or small, it will cause the filling rate difference coefficient to be large, so when the filling rate is small, the filling rate offset coefficient is large; when the filling rate is large, the filling rate offset coefficient is even larger; so when the filling rate is large, the larger the filling distribution coefficient and the larger the filling rate difference coefficient, the larger the filling rate offset coefficient; on the contrary, when the filling rate is small, the smaller the filling distribution coefficient and the smaller the filling rate difference coefficient, the smaller the filling rate offset coefficient.

[0082] Preferably, the schematic diagram of the process for extracting the filling rate offset coefficient provided in this embodiment is as Figure 3 shown.

[0083] Step S4: Obtain the filling mass and filling volume of the mixed material in the mixer multiple times, and combine the filling rate offset coefficient to determine the first and second fitting functions of the mixer; based on the first and second fitting functions and the filling rate offset coefficient, determine the filling mass adjustment amount of the mixer at the current moment, and control the mixed material in the mixer.

[0084] (1)When the types of components of the mixed materials in the mixer are the same, record the different filling masses and corresponding filling volumes of the mixed materials. Each time the filling mass and filling volume are collected, and according to the method for obtaining the filling rate offset coefficient of the mixer at the current moment in steps S1 - S3, calculate the filling rate offset coefficient of the mixer for the corresponding collection;

[0085] Furthermore, take the ratio of the filling mass and filling volume of the mixed materials for each collection as the filling density of the mixed materials for each collection;

[0086] Among all the collections, obtain the minimum value of the filling rate offset coefficients for all the collections corresponding to each filling density, and take the filling mass of the mixed materials for the collection corresponding to the minimum value as the optimal filling mass for this filling density (Note: Although the filling mass and filling volume are different, the calculated filling densities may be the same. If the filling densities are the same, obtain the minimum value of the filling rate offset coefficients for all the collections corresponding to this filling density, and take the filling mass of the mixed materials for the collection corresponding to the minimum value as the optimal filling mass for this filling density; if the filling densities are all different, each filling density corresponds to a filling rate offset coefficient and a filling mass, and this filling mass is the optimal filling mass);

[0087] Take all the filling densities and their respective optimal filling masses as the independent variable and dependent variable of the fitting algorithm respectively, and output the fitting function between the filling density and the optimal filling mass as the first fitting function;

[0088] It should be noted that there are many commonly used fitting algorithms. In this embodiment, the non - linear least - squares fitting algorithm is used to obtain the fitting function. Implementers can also use other fitting methods such as polynomial fitting. There is no special limitation on the selection of the fitting algorithm in this embodiment.

[0089] Among them, the non - linear least - squares fitting algorithm is a well - known technology, and its specific fitting process will not be elaborated here.

[0090] Preferably, the schematic diagram of the first fitting function provided in this embodiment is as Figure 4 shown, Figure 4 in which the abscissa represents the filling density, with the unit of ; the ordinate is the optimal filling mass, with the unit of ; Figure 4 the solid line in

[0091] represents the fitting curve, and the points represent the original data.

[0092] (2)When the filling masses of the mixed materials in the mixer are the same, obtain the filling volumes of the mixed materials when the types of the mixed materials are different, and calculate the filling density;

[0092] Take the filling rate offset coefficient and the respective filling densities of the mixer under all sub-collections as the independent variable and the dependent variable of the fitting algorithm respectively, and output the fitting function between the filling rate offset coefficient and the filling density as the second fitting function.

[0093] It should be noted that in this embodiment, the method of controlling variables is adopted. First, control the types of components of the mixed materials to be the same and change the filling mass, so as to analyze the relationship between the filling density and the optimal filling mass to obtain the first fitting function. Secondly, control the types of components of the mixed materials to be different, but the filling mass is the same, so as to analyze the relationship between the filling density and the filling rate offset index to obtain the second fitting function. Combine the first and second fitting functions to obtain the relationship between the filling rate offset coefficient and the optimal filling mass; if the types of components of the mixed materials and the filling mass are changed at the same time, there may be a situation where the types of components of the mixed materials are different, but the filling mass is the same, so that the filling mass cannot be corresponding to the types of components of the mixed materials. Therefore, the situation of changing the types of components of the mixed materials and the filling mass at the same time is not considered.

[0094] Preferably, the schematic diagram of the second fitting function provided in this embodiment is as Figure 5 shown Figure 5 where the abscissa represents the filling rate offset coefficient, without unit; the ordinate represents the filling density, and the unit is ; Figure 5 The solid line in the figure represents the fitting curve, and the points represent the original data.

[0095] (3) Based on the first and second fitting functions and the filling rate offset coefficient, determine the filling mass adjustment amount of the mixer at the current moment, specifically:

[0096] The filling mass adjustment amount of the mixer at the current moment has the following expression: ; where represents the filling rate offset coefficient of the mixer at the current moment; represents the first fitting function of the mixer at the current moment;

[0097] represents the second fitting function of the mixer at the current moment; M represents the preset filling mass.

[0098] It should be noted that the value of the preset filling quality M is set manually. In this embodiment, the preset filling quality is 2000 kg. The implementer can also set it according to specific circumstances by himself / herself, and this embodiment does not make special restrictions.

[0099] So far, in this embodiment, by monitoring the real-time data of the mixed materials in the mixer and adjusting the filling rate of the mixer in a timely and accurate manner, the influence of using a fixed filling rate threshold on the low control accuracy of the filling rate is avoided, thereby improving the accuracy of filling rate control, enhancing the mixing uniformity of the filled materials, and further contributing to improving the quality of subsequent product production.

[0100] Based on the same inventive concept as the above method, an embodiment of the present application also provides a mixer, including a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, it implements the steps of any one of the above methods for automatically controlling the filling rate of a mixer.

[0101] It should be noted that the above sequence of embodiments of the present application is only for description and does not represent the superiority or inferiority of the embodiments. And the above describes specific embodiments of this specification. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0102] Each embodiment in this specification is described in a progressive manner. The same or similar parts among the embodiments can be referred to each other, and the key points of each embodiment are the differences from other embodiments.

[0103] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for automatically controlling the filling rate of a mixer, characterized in that: The method comprises the following steps: Obtain the rotation speed data of the mixer at all sampling moments within a preset time period before the current moment, and the vibration data of the mixer at all sampling moments in all directions; Divide the preset time into multiple time periods, and determine the vibration measurement value of the mixer at the current moment based on the discrete degree of all vibration data in each direction of the mixer in each time period; determine the difference degree of the mixer in each time period based on the difference of all vibration data between any two directions of the mixer in each time period, and determine the filling rate difference coefficient of the mixer at the current moment in combination with the vibration measurement value; Based on the discreteness of all the rotation speed data of the mixer in the last period before the current moment, and the discreteness and average distribution of all the rotation speed data of the mixer in the preset time, determine the filling distribution coefficient of the mixer at the current moment, and combine the filling rate difference coefficient to determine the filling rate deviation coefficient of the mixer at the current moment; The filling mass and filling volume of the mixed material in the mixer are obtained multiple times, and the first and second fitting functions of the mixer are determined in combination with the filling rate offset coefficient; based on the first and second fitting functions and the filling rate offset coefficient, the filling mass adjustment amount of the mixer at the current moment is determined to control the mixed material in the mixer.

2. A method for automatically controlling the filling rate of a mixer as claimed in claim 1, characterized in that: The method for determining the vibration measurement value of the mixer at the current moment is: Calculating the variance of all vibration data in all directions of the mixer in each time period, fitting the variance of the vibration data in all directions of the mixer in all time periods, and obtaining a fitting straight line in all directions of the mixer; The vibration measurement value of the mixer at the current moment is the average level of the slope of the fitting line in all directions of the mixer.

3. A method for automatically controlling the filling rate of a mixer as claimed in claim 1, characterized in that: The method for determining the difference of the mixer in each time period is as follows: Calculate the difference of all vibration data between any two directions of the mixer in each period, and record it as the difference value between any two directions of the mixer in each period; The difference degree of the mixer in each period is the mean of the difference values ​​between all two-direction combinations of the mixer in each period.

4. A method for automatically controlling the filling rate of a mixer as claimed in claim 1, characterized in that: The expression of the filling rate difference coefficient of the mixer at the current moment is: ; In the formula, A represents the filling rate difference coefficient of the mixer at the current moment; Indicates the vibration measurement value of the mixer at the current moment; Indicates the difference between the mixers in the last period before the current moment; It indicates the difference between the mixers in time period i before the current moment; represents the difference of the mixer in the time period i+1 before the current moment; n represents the number of all time periods within the preset time length before the current moment.

5. A method for automatically controlling the filling rate of a mixer as claimed in claim 1, characterized in that: The method for determining the filling distribution coefficient of the mixer at the current moment is: Record the discrete degree of all the rotation speed data of the mixer in the last period before the current moment as the first discrete degree of the mixer at the current moment; Record the discrete degree of all the rotation speed data of the mixer within a preset time period before the current moment as the second discrete degree of the mixer at the current moment; The product of the average level of all the rotation speed data of the mixer within a preset time before the current moment and the second discrete degree is calculated, and the ratio of the first discrete degree to the product is used as the filling distribution coefficient of the mixer at the current moment.

6. A method for automatically controlling the filling rate of a mixer as claimed in claim 4, characterized in that: The expression of the filling rate deviation coefficient of the mixer at the current moment is: ; In the formula, Indicates the filling rate deviation coefficient of the mixer at the current moment; It represents the filling distribution coefficient of the mixer at the current moment; exp( ) represents an exponential function with a natural constant as the base.

7. A method for automatically controlling the filling rate of a mixer as claimed in claim 1, characterized in that: The method for determining the first and second fitting functions of the mixer at the current moment is: When the components of the mixed materials in the mixer are the same, record the different filling masses and corresponding filling volumes of the mixed materials, collect the filling mass and filling volume each time, and calculate the filling rate deviation coefficient of the mixer under the corresponding collection according to the method for obtaining the filling rate deviation coefficient of the mixer at the current moment; The ratio of the filling mass and the filling volume of the mixed material collected each time is taken as the filling density of the mixed material collected each time; Under all acquisitions, the minimum value of the filling rate deviation coefficient under all acquisitions corresponding to each filling density is obtained, and the filling mass of the mixed material under the acquisition corresponding to the minimum value is taken as the optimal filling mass of the filling density; All filling densities and their respective optimal filling masses are used as independent variables and dependent variables of the fitting algorithm, and a fitting function between the filling density and the optimal filling mass is output as a first fitting function; When the filling mass of the mixed materials in the mixer is the same, the filling volume of the mixed materials with different types is obtained, and the filling density is calculated; The filling rate deviation coefficients and respective filling densities of the mixers collected at all times are used as the independent variable and dependent variable of the fitting algorithm, and a fitting function between the filling rate deviation coefficient and the filling density is output as the second fitting function.

8. A method for automatically controlling the filling rate of a mixer as claimed in claim 1, characterized in that: The expression of the filling mass adjustment amount of the mixer at the current moment is: ; In the formula, Indicates the filling mass adjustment amount of the mixer at the current moment; Indicates the filling rate deviation coefficient of the mixer at the current moment; represents the first fitting function of the mixer at the current moment; represents the second fitting function of the mixer at the current moment; M represents the preset filling quality.

9. A method for automatically controlling the filling rate of a mixer as claimed in claim 1, characterized in that: The control of the mixed material in the mixer comprises: If the filling mass adjustment amount of the mixer at the current moment is a negative number, the discharge port of the mixer is opened to discharge the mixed material of the filling mass adjustment amount; if the filling mass adjustment amount of the mixer at the current moment is a positive number, the feed port of the mixer is opened to inject the mixed material of the filling mass adjustment amount.

10. A mixer, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the steps of the automatic control method of the filling rate of a mixer as described in any one of claims 1 to 9 are implemented.

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