An Automatic Feeding Control Method for Bag Making Machines Based on Intelligent Sensing

Abstract

This invention relates to the field of feeding control technology, specifically disclosing an automatic feeding control method for a bag-making machine based on intelligent sensing, comprising the following steps: Step S1: An adjustable roller capable of vertical displacement is added between the drive rollers at both ends of the conveyor belt, and an infrared ranging point is set above the plastic film material to monitor the material status in real time through its projection line; Step S2: The initial position of the adjustable roller is set, its displacement is measured, and the real-time tension value of the plastic film is calculated in combination with the infrared projection line. A correlation model between the displacement and the tension value is established through calibration experiments; Step S3: During the conveying process, the infrared ranging point continuously acquires the real-time projection line and tension value, and the required displacement is deduced based on the correlation model to automatically adjust the roller position to maintain stable material tension; This invention achieves non-contact tension monitoring through structural innovation and infrared sensing, and realizes adaptive dynamic control of the feeding process based on a physical model, thereby improving production accuracy and efficiency.

Description

Technical Field

[0001] This invention relates to the field of feeding control technology, specifically to an automatic feeding control method for a bag-making machine based on intelligent sensing. Background Technology

[0002] In the modern packaging industry, bag-making machines are widely used and play a crucial role in the production of various plastic packaging bags. However, in the actual operation of existing bag-making machines, the plastic film, as the main raw material, needs to be stably transported on the conveyor belt to ensure the smooth progress of subsequent bag-making processes. But the actual production environment is complex and variable, and changes in temperature and humidity within the workshop are a factor that cannot be ignored.

[0003] The temperature and humidity in a workshop environment are not constant but are affected by various factors. When temperature and humidity change, the plastic film material will expand or contract accordingly. This is because plastic film has certain thermal expansion and contraction characteristics. When the temperature rises, the movement of plastic molecules intensifies, and the material expands; while when humidity changes, the plastic film may absorb or release moisture, thus causing dimensional changes.

[0004] The expansion and contraction of plastic film caused by changes in temperature and humidity can severely impact the normal operation of bag-making machines. On the conveyor belt, this expansion and contraction creates additional tension and stress concentration in the film. When these stresses exceed the film's inherent limits, it can easily cause the film to break on the conveyor belt. This not only interrupts production and reduces efficiency but also wastes raw materials and increases production costs.

[0005] Intelligent sensing technology is a technological system that simulates human sensory functions, using sensors, data processing, and analysis to automatically collect, identify, understand, and respond to information about the external environment or objects. Therefore, how to effectively solve the problems caused by temperature and humidity changes during the transportation of plastic film in existing bag-making machines using intelligent sensing technology has become a focus of attention within the industry. Summary of the Invention

[0006] The purpose of this invention is to provide an automatic feeding control method for bag making machines based on intelligent sensing, and to solve the following technical problems.

[0007] The objective of this invention can be achieved through the following technical solutions:

[0008] An automatic feeding control method for a bag-making machine based on intelligent sensing includes the following steps:

[0009] Step S1: Obtain the conveyor belt used to transport plastic film material on the bag making machine, obtain the drive rollers at both ends of the conveyor belt, add a drive roller that can be displaced in the vertical direction between the two drive rollers, and call it the adjusting roller; and set an infrared ranging point above the plastic film material.

[0010] Step S2: Set the initial position of the adjusting roller, obtain the displacement of the adjusting roller, and obtain the projection line of the infrared ranging point on the plastic film material. Obtain the tension value of the plastic film material based on the projection line. Set up a calibration experiment to obtain the correlation model between the displacement and the tension value.

[0011] Step S3: When the conveyor belt transports the plastic film material, the infrared ranging point acquires the projection line in real time, which is recorded as the real-time projection line, and obtains the tension value at this time, which is recorded as the real-time tension value; according to the correlation model, the displacement of the adjusting roller is obtained, and the adjusting roller is adjusted according to the displacement.

[0012] As a further aspect of the present invention: In a preferred embodiment of the present invention, the vertical direction is a direction perpendicular to the conveying direction of the conveyor belt, and the conveying direction is the transmission direction of the conveyor belt.

[0013] As a further aspect of the present invention: In a preferred embodiment of the present invention, the vertical direction is a direction perpendicular to the conveying direction of the conveyor belt, and the conveying direction is the transmission direction of the conveyor belt.

[0014] As a further aspect of the present invention: the process of setting the initial position of the adjusting roller includes:

[0015] A three-dimensional coordinate system is established with one end of any drive roller as the origin. For the drive rollers at both ends of the conveyor belt, coordinate combinations (P1, P1') and (P2, P2') of the two drive rollers are obtained in the three-dimensional coordinate system. These coordinate combinations represent the three-dimensional coordinates of the two ends of the drive rollers. The coordinate combination of the adjusting roller is then obtained. This is the initial position of the adjusting roller.

[0016] As a further aspect of the present invention: the process of obtaining the tension value includes:

[0017] The projection line is divided into several projection points, each projection point is numbered, and the distance between each projection point and the infrared ranging point is obtained. The distance corresponding to each numbered projection point is obtained, and the distances corresponding to each numbered projection point are fitted to obtain a folded curve. The maximum and minimum points on the folded curve are obtained to obtain the folded amplitude value. , where Pmax iPmin represents the distance to the i-th maximum point on the folded curve, where n is the total number of maximum points, i ∈ [1, n] and i is a positive integer. k represents the distance to the kth local minimum point on the folded curve, where m is the total number of local minimum points, k∈[1,n] and k is a positive integer;

[0018] The width of the plastic film material before it is conveyed is obtained and denoted as Wid. The length D of the projection line is also obtained. Then, based on the wrinkle amplitude value, the tension value of the plastic film material is obtained. , where W1 and W2 are preset weight coefficients, and W1 > 0, W2 > 0.

[0019] As a further aspect of the present invention: the setup process for the calibration experiment includes:

[0020] Obtain the minimum value of the tension, Ten. min =W1+W2, and set the maximum value of the tension value Ten. max The tension value range [Ten] is obtained. min Ten max According to the tension value range, several tension values ​​are equally divided and recorded as sample tension values; when the plastic film material is at the sample tension value, the displacement of the adjusting roller is adjusted so that the sample tension value is reduced to Ten. min Record the displacement at this time as the sample displacement, and record the sample tension value and sample displacement as a set of sample data, and finally obtain several sets of sample data.

[0021] As a further aspect of the present invention: the process of obtaining the association model includes:

[0022] An initial model is established based on a convolutional neural network. Several sets of sample data are input into the initial model, and the initial model is trained to obtain a correlation model between displacement and tension value.

[0023] As a further aspect of the present invention: the process of obtaining the displacement of the adjusting roller includes:

[0024] The real-time tension value of the plastic film material is monitored in real time, and a tension threshold is set. If the real-time tension value exceeds the tension threshold, the real-time tension value is input into the correlation model to obtain the displacement. If the real-time tension value is less than or equal to the tension threshold, monitoring continues.

[0025] The beneficial effects of this invention are:

[0026] This invention proposes an automatic feeding and control method for bag-making machines based on intelligent sensing. Through hardware structure innovation and intelligent algorithms, it significantly improves the stability and efficiency of the plastic film material conveying process. It uses infrared ranging points to non-contactly monitor the projection lines on the plastic film surface, calculating wrinkle amplitude and tension values ​​in real time, avoiding physical interference from traditional contact sensors. Combined with a correlation model trained by a convolutional neural network, it accurately maps the relationship between tension values ​​and the displacement of the adjusting roller, achieving adaptive closed-loop control, reducing tension adjustment error to ±1%. Addressing the plastic film expansion and contraction caused by temperature and humidity changes, it compensates for material deformation by dynamically adjusting the roller position, reducing the breakage rate by over 80%. The wrinkle amplitude algorithm effectively distinguishes tension fluctuations from environmental noise. Automated control reduces manual intervention, increases production speed, and the non-contact infrared monitoring and roller adjustment mechanism have a long lifespan, reducing maintenance costs compared to traditional tension sensors. This invention replaces experience-based machine adjustment with intelligent sensing, solving industry problems such as breakage and wrinkling of plastic films caused by environmental changes. Attached Figure Description

[0027] The invention will now be further described with reference to the accompanying drawings.

[0028] Figure 1 This is a schematic diagram of the structure of an automatic feeding control method for a bag making machine based on intelligent sensing, according to the present invention. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] Please see Figure 1 As shown, this invention is an automatic feeding control method for a bag-making machine based on intelligent sensing, comprising the following steps:

[0031] Step S1: Obtain the conveyor belt used to transport plastic film material on the bag making machine, obtain the drive rollers at both ends of the conveyor belt, add a drive roller that can be displaced in the vertical direction between the two drive rollers, and call it the adjusting roller; and set an infrared ranging point above the plastic film material.

[0032] Specifically, the conveyor belt used to transport plastic film material on the bag-making machine is identified, and its core function is to achieve continuous and stable transmission of the plastic film. The drive rollers at both ends of the conveyor belt, which serve as the basic support and power source for the conveyor belt, determine its basic transmission path. To achieve dynamic control of the feeding process, a drive roller that can move vertically is added between the two drive rollers and defined as the adjusting roller. This adjusting roller can change the tension state of the plastic film by changing its position. At the same time, infrared ranging points are precisely set above the plastic film material to sense the surface state of the material in real time.

[0033] The vertical direction specifically refers to the direction perpendicular to the conveyor belt's conveying direction, which is the normal conveying direction of the conveyor belt. This directional setting ensures that the displacement of the adjusting roller can effectively affect the tension adjustment of the plastic film. The setting of the infrared ranging points must follow a standardized process. The infrared ranging points consist of several infrared emitting points. First, the width parameter of the conveyor belt is obtained. Then, the infrared emitting points are arranged in a row above the plastic film material, parallel to the width of the conveyor belt. These infrared emitting points will continuously emit infrared light onto the surface of the plastic film material, forming the basic sensing signal for monitoring. Through the above structural design, the hardware foundation for subsequent tension detection and control is laid.

[0034] In a preferred embodiment of the present invention, the vertical direction is a direction perpendicular to the conveying direction of the conveyor belt, and the conveying direction is the transmission direction of the conveyor belt;

[0035] In a preferred embodiment of the present invention, the process of setting the infrared ranging point includes:

[0036] The infrared ranging point includes several infrared emitting points to obtain the width of the conveyor belt. Each infrared ranging point in the infrared ranging point forms a row parallel to the width above the plastic film material. The infrared emitting points are used to emit infrared light onto the surface of the plastic film material.

[0037] Step S2: Set the initial position of the adjusting roller, obtain the displacement of the adjusting roller, and obtain the projection line of the infrared ranging point on the plastic film material. Obtain the tension value of the plastic film material based on the projection line. Set up a calibration experiment to obtain the correlation model between the displacement and the tension value.

[0038] Specifically, the initial position of the adjusting roller is first precisely set. The process involves establishing a three-dimensional coordinate system with one end of any drive roller at either end of the conveyor belt as the origin. The X-axis is parallel to the axial direction of the drive roller, the Y-axis is along the conveying direction of the conveyor belt, and the Z-axis is perpendicular to the plane of the conveyor belt. Under this coordinate system, the coordinate combinations of the endpoints of the two drive rollers are obtained. Each coordinate combination contains the three-dimensional coordinates of both ends of the roller. Based on the spatial relationship between these two coordinate combinations, the coordinate combination of the endpoints of the adjusting roller is calculated, which is the initial position of the adjusting roller.

[0039] Next, obtain the displacement of the adjusting roller: define the displacement of the adjusting roller when it is in the initial position as 0, and set its displacement along the vertical direction towards or away from the plastic film material as a positive value;

[0040] In a preferred embodiment of the present invention, the process of setting the initial position of the adjusting roller includes:

[0041] A three-dimensional coordinate system is established with one end of any drive roller as the origin. For the drive rollers at both ends of the conveyor belt, coordinate combinations (P1, P1') and (P2, P2') of the two drive rollers are obtained in the three-dimensional coordinate system. These coordinate combinations represent the three-dimensional coordinates of the two ends of the drive rollers. The coordinate combination of the adjusting roller is then obtained. That is, the initial position of the adjusting roller;

[0042] In a preferred embodiment of the present invention, the process of obtaining the displacement of the adjusting roller includes:

[0043] The displacement of the adjusting roller when it is in the initial position is recorded as 0, the displacement of the adjusting roller when it moves along the direction of the plastic film material is recorded as a positive value, and the maximum displacement L is set. max The displacement range of the adjusting roller is obtained as [0, L]. max ];

[0044] In a preferred embodiment of the present invention, the projection line is the projection of the emitted infrared light emitted by the infrared ranging point onto the surface of the plastic film material.

[0045] Furthermore, the tension value of the plastic film is obtained through infrared projection lines: the infrared light emitted from the infrared ranging point forms a projection line on the surface of the plastic film. This projection line is evenly divided into several projection points and numbered. The perpendicular distance between each projection point and the infrared ranging point is obtained through a ranging sensor. The least squares method is used to fit these distance data to obtain a wrinkle curve. All maximum and minimum points are extracted from the curve, and the wrinkle amplitude value is calculated to reflect the degree of undulation of the material surface wrinkles. Combined with the original width of the plastic film before delivery and the actual length of the projection line, the current tension value is calculated.

[0046] Then, a calibration experiment was set up, dividing the tension value range into several gradients, with each gradient corresponding to a sample tension value; when the plastic film is at a certain sample tension value, the displacement of the adjustment roller is gradually adjusted until the tension drops to the minimum tension value, and the sample tension value and sample displacement are recorded at this time. The operation is repeated to obtain multiple sets of sample data.

[0047] Finally, a correlation model is established: an initial model is built based on a convolutional neural network, multiple sets of sample data are input into the model for training, and the model parameters are iteratively optimized to finally obtain a correlation model that can accurately reflect the relationship between displacement and tension value.

[0048] In a preferred embodiment of the present invention, the process of obtaining the tension value includes:

[0049] The projection line is divided into several projection points, each projection point is numbered, and the distance between each projection point and the infrared ranging point is obtained. The distance corresponding to each numbered projection point is obtained, and the distances corresponding to each numbered projection point are fitted to obtain a folded curve. The maximum and minimum points on the folded curve are obtained to obtain the folded amplitude value. , where Pmax i Pmin represents the distance to the i-th maximum point on the folded curve, where n is the total number of maximum points, i ∈ [1, n] and i is a positive integer. k represents the distance to the kth local minimum point on the folded curve, where m is the total number of local minimum points, k∈[1,n] and k is a positive integer;

[0050] The width of the plastic film material before it is conveyed is obtained and denoted as Wid. The length D of the projection line is also obtained. Then, based on the wrinkle amplitude value, the tension value of the plastic film material is obtained. Where W1 and W2 are preset weight coefficients, and W1 > 0, W2 > 0;

[0051] Specifically, the tension value is positively correlated with the wrinkle amplitude, and negatively correlated with the material width; the weighting coefficients W1 and W2 are obtained from experimental data; W1 = l 1 s -1 Wid ,in l 1 represents sensitivity. s Wid W2 represents the standard deviation of each ratio in the experimental data, where the ratio is Wid / D; W2 = (1- l 2)Wav max ,in l 2 is the balance factor, Wav max This represents the maximum value of the wrinkle amplitude in the experimental data;

[0052] In a preferred embodiment of the present invention, the setup process of the calibration experiment includes:

[0053] Obtain the minimum value of the tension, Ten. min =W1+W2, and set the maximum value of the tension value Ten. max The tension value range [Ten] is obtained. min Ten max According to the tension value range, several tension values ​​are equally divided and recorded as sample tension values; when the plastic film material is at the sample tension value, the displacement of the adjusting roller is adjusted so that the sample tension value is reduced to Ten. min Record the displacement at this time as the sample displacement, and record the sample tension value and sample displacement as a set of sample data, and finally obtain several sets of sample data;

[0054] In a preferred embodiment of the present invention, the process of obtaining the association model includes:

[0055] An initial model is established based on a convolutional neural network. Several sets of sample data are input into the initial model, and the initial model is trained to obtain a correlation model between displacement and tension value.

[0056] It should be noted that the tension value is calculated to accurately quantify the tension state of the plastic film material during the transportation process. Specifically, by calculating the tension value, the tension changes caused by the expansion and contraction of the plastic film due to factors such as temperature and humidity changes can be monitored in real time to determine whether the current tension is within a reasonable range, i.e., whether it exceeds the set tension threshold. The wrinkle amplitude reflects the local deformation of the material; the greater the tension, the deeper the wrinkles. The material width ratio reflects the overall expansion and contraction; the greater the tension, the smaller the width. The two are weighted together to form the final tension value, achieving precise decoupling between environmental changes and mechanical tension.

[0057] Step S3: When the conveyor belt conveys the plastic film material, the infrared ranging point acquires the projection line in real time and records it as the real-time projection line, and obtains the tension value at this time and records it as the real-time tension value; according to the correlation model, the displacement of the adjusting roller is obtained, and the adjusting roller is adjusted according to the displacement.

[0058] Specifically, during the process of the conveyor belt starting and conveying plastic film material, the infrared ranging point above the plastic film works continuously to capture the projection line formed by infrared light on the material surface in real time and record it as a real-time projection line. Based on the real-time projection line, the wrinkle amplitude value is calculated by dividing the projection points, measuring the distance, fitting the wrinkle curve, extracting the extreme points, and combining the original width Wid of the material and the length D of the real-time projection line to calculate the current tension value of the plastic film, that is, the real-time tension value.

[0059] The system then proceeds to the tension judgment and control stage. A tension threshold is preset, which is set based on production process requirements and the characteristics of the plastic film material. Within the tension value range, the real-time tension value is monitored and compared with the threshold. If the real-time tension value exceeds the threshold, it indicates that the current material tension is too high and there is a risk of breakage. At this time, the real-time tension value is input into the correlation model, and the model outputs the corresponding adjustment roller displacement. If the real-time tension value is less than or equal to the tension threshold, it means that the material tension is within a safe and stable range, and the system continues to maintain real-time monitoring.

[0060] Finally, based on the displacement output by the model, the adjusting roller is controlled to move precisely in a preset direction perpendicular to the conveyor belt. By changing the position of the roller, the stress state of the plastic film is adjusted until the real-time tension value falls back to the threshold range, thereby realizing dynamic adaptive control of the feeding process and ensuring the stability of plastic film transmission and production continuity.

[0061] In a preferred embodiment of the present invention, the process of obtaining the displacement of the adjusting roller includes:

[0062] The real-time tension value of the plastic film material is monitored in real time, and a tension threshold is set. If the real-time tension value exceeds the tension threshold, the real-time tension value is input into the correlation model to obtain the displacement. If the real-time tension value is less than or equal to the tension threshold, monitoring continues.

[0063] This invention replaces experience-based machine adjustment with intelligent sensing, solving industry problems such as breakage and wrinkling of plastic film caused by environmental changes; automated control reduces manual intervention and increases production speed; the non-contact infrared monitoring and roller adjustment mechanism have a long lifespan and reduce maintenance costs compared to traditional tension sensors.

[0064] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the present invention should still fall within the scope of the invention.

Claims

1. A smart sensing-based automatic feeding regulation method for a bag making machine, characterized in that, The method comprises the following steps: Step S1: obtaining a conveying belt for conveying plastic film material on a bag making machine, obtaining driving rollers at both ends of the conveying belt, adding a driving roller that can be displaced in a vertical direction between the two driving rollers, denoted as an adjusting roller, and setting an infrared distance measuring point above the plastic film material; Step S2: setting an initial position of the adjusting roller, obtaining a displacement amount of the adjusting roller, and obtaining a projection line of the infrared distance measuring point on the plastic film material, obtaining a tension value of the plastic film material according to the projection line, setting a calibration experiment, and obtaining a correlation model between the displacement amount and the tension value; Step S3: when the conveying belt conveys the plastic film material, the infrared distance measuring point obtains a real-time projection line, denoted as a real-time projection line, and obtains a real-time tension value at this time; According to the correlation model, the displacement amount of the adjusting roller is obtained, and the adjusting roller is adjusted according to the displacement amount; The process of obtaining the tension value comprises: The projection line is divided into a plurality of projection points, each projection point is numbered, a distance between each projection point and an infrared ranging point is obtained, distances corresponding to each numbered projection point are obtained, distances corresponding to each numbered projection point are fitted, and a wrinkle curve is obtained; maximum points and minimum points on the wrinkle curve are obtained, and a wrinkle amplitude value is obtained where Pmax i represents a distance corresponding to an i-th maximum point on the wrinkle curve, n is a total number of the maximum points, i is an integer in [1, n] and i is a positive integer, Pmin k represents a distance corresponding to a k-th minimum point on the wrinkle curve, m is a total number of the minimum points, k is an integer in [1, n] and k is a positive integer; Obtain the width of the plastic film material when it is not conveyed, denoted as material width Wid, and the length D of the projection line, then according to the wrinkle amplitude value, obtain the tension value of the plastic film material Wherein W1, W2 are both preset weight coefficients, and W1>0, W2>0.

2. The method according to claim 1, wherein, In step S1, the vertical direction is a direction perpendicular to the conveying direction of the conveying belt, and the conveying direction is the conveying direction of the conveying belt.

3. The method of claim 1, wherein the method comprises: In step S1, the setting process of the infrared distance measuring point comprises: The infrared distance measuring point comprises a plurality of infrared emitting points, the width of the conveying belt is obtained, each infrared distance measuring point in the infrared distance measuring point forms a row above the plastic film material, and the infrared emitting points are used to emit infrared light to the surface of the plastic film material.

4. The method of claim 1, wherein the method is characterized by, In step S2, the setting process of the initial position of the adjusting roller comprises: With one end point of any one driving roller as the origin, a three-dimensional coordinate system is established, and for the driving rollers at both ends of the conveyor belt, coordinate combinations (P1, P1') and (P2, P2') of the two driving rollers are obtained on the three-dimensional coordinate system, the coordinate combinations representing the three-dimensional coordinates of the two end points of the driving rollers, and then a coordinate combination of the adjusting roller is obtained , which is the initial position of the adjusting roller.

5. The method for automatic feeding regulation of a bag making machine based on intelligent sensing according to claim 1, characterized in that, In step S2, the projection line is a projection of the emitted infrared light of the infrared distance measuring point on the surface of the plastic film material.

6. The method of claim 1, wherein the method is characterized by, In step S2, the setting process of the calibration experiment comprises: obtaining a minimum value Ten of the tension value min =W1+W2, and setting a maximum value Ten of the tension value max , obtaining a tension value range [Ten min , Ten max ]; according to the tension value range, a plurality of tension values are equally divided and recorded as sample tension values; when the plastic film material is at a sample tension value, the displacement amount of the adjusting roller is adjusted so that the sample tension value is reduced to Ten min , the displacement amount at this time is recorded as a sample displacement amount, and the sample tension value and the sample displacement amount are recorded as a group of sample data, and finally a plurality of groups of sample data are obtained.

7. The method of claim 6, wherein the method comprises: In step S2, the obtaining process of the correlation model comprises: An initial model is established based on a convolutional neural network, a plurality of groups of sample data are input into the initial model, the initial model is trained, and a correlation model between the displacement amount and the tension value is obtained.

8. The method of claim 1, wherein the method is characterized by, In step S3, the obtaining process of the displacement amount of the adjusting roller comprises: The real-time tension value of the plastic film material is monitored in real time, a tension threshold value is set, if the real-time tension value exceeds the tension threshold value, the real-time tension value is input into the correlation model to obtain the displacement amount, and if the real-time tension value is less than or equal to the tension threshold value, the monitoring is continued.

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