Ultra-large roll unwinding PLC control method and device, electronic equipment and storage medium

Abstract

The invention provides an ultra-large roll unwinding PLC control method and device, electronic equipment and a storage medium, which are applied to the technical field of automatic control, and are used for dynamically calculating the rotating speed and the frequency required by a motor by acquiring the winding drum information and the linear speed in real time in the unwinding process, and performing closed-loop control, so that the winding drum unwinding speed is improved. The problems of insufficient control precision and unstable operation caused by fixed parameters in the prior art are effectively solved, so that real-time, dynamic and accurate control over the ultra-large reel unwinding process can be achieved, and the problems of linear speed fluctuation, out-of-control tension, strip damage, unstable motor operation and the like caused by the fixed parameters in the prior art are effectively solved; and the unwinding safety, continuity and production efficiency are remarkably improved.

Description

Technical Field

[0001] The present application relates to the field of automation control technology, and in particular to a PLC control method, device, electronic device and storage medium for unwinding an oversized roll. Background Art

[0002] With the rapid development of e-commerce, logistics, and manufacturing, the use of strapping tape (PP, PET, steel, etc.) for pallet and box strapping has increased exponentially. To reduce roll changes and improve overall line performance, upstream extrusion / stretching equipment now generally winds the finished strip into ton-level, vertical, oversized rolls.

[0003] However, the existing unwinding devices and their PLC control methods mostly follow the design ideas of traditional small and medium-sized rolls, which seriously restricts the safe, continuous and accurate unwinding of oversized rolls.

[0004] In the existing technology, existing PLC programs mostly use a fixed coil diameter or a segmented table lookup method to estimate the rotational speed, and lack a closed-loop update mechanism based on real-time counting. This causes large fluctuations in line speed, uncontrolled tension, and the strip is easily broken or stacked. Moreover, due to the drastic changes in coil diameter, parameters such as the motor reduction ratio and rated speed are often hard-coded in the program. The system cannot automatically correct the motor target frequency according to the real-time coil diameter, resulting in insufficient torque in the low-speed section and overspeed alarms in the high-speed section. The equipment frequently stops suddenly, seriously affecting production efficiency.

[0005] Therefore, the market urgently needs a PLC control method that can obtain roll information in real time and accurately calculate the motor speed and frequency to meet the needs of high-speed, stable and automated unwinding of extra-large rolls. Summary of the Invention

[0006] In view of the above-mentioned shortcomings of the existing technology, the present application provides a PLC control method, device, electronic equipment and storage medium for unwinding of super-large rolls, which are applied to the field of automatic control technology. It can realize real-time, dynamic and precise control of the unwinding process of super-large rolls, and has the advantages of effectively solving the problems of line speed fluctuation, tension loss of control, strip damage and unstable motor operation caused by fixed parameters in the existing technology, and significantly improving the safety, continuity and production efficiency of unwinding.

[0007] In a first aspect, a PLC control method for unwinding an oversized roll is provided, the method comprising the steps of: S1: After the unwinding machine operation button is turned on, determine whether the unwinding position of the reel on the unwinding machine is abnormal; S2: If there is no abnormality in the unwinding position of the reel, start the unwinding machine and obtain the reel information of the strapping tape and the unwinding speed of the strapping tape; S3: Calculating the reel rotation speed according to the reel information and the unwinding line speed; S4: Obtaining the motor reduction ratio, and calculating the required motor speed and motor frequency in combination with the drum speed; S5: controlling the motor to operate according to the required speed and frequency of the motor, thereby controlling the unwinding machine to unwind.

[0008] The present application provides a PLC control method for unwinding extra-large rolls. The method performs abnormality judgment before the unwinding machine is started, and after normal startup, based on the acquired roll information and unwinding line speed, combined with the motor reduction ratio, accurately calculates the required speed and frequency of the motor, and then controls the motor operation to achieve stable and accurate unwinding of extra-large rolls, avoiding the problems of line speed fluctuation and control instability caused by fixed parameters or inaccurate estimation in traditional methods.

[0009] Furthermore, the method further comprises the steps of: S6: During the unwinding process of the unwinding machine, a reading of a photoelectric detection counter is obtained in real time; S7: Calculating real-time updated information of the reel based on the reading and the reel information; S8: Calculating the real-time updated rotation speed of the reel according to the real-time updated information and the unwinding line speed; S9: Calculating the required speed and frequency of the motor for real-time update according to the motor reduction ratio and the real-time update speed of the reel; S10: controlling the operation of the motor according to the real-time updated required speed of the motor and the real-time updated required frequency of the motor, thereby controlling the unwinding of the unwinder.

[0010] The present application provides a PLC control method for unwinding an extra-large roll, which further realizes closed-loop control of the unwinding process and real-time correction of parameters by obtaining the readings of the photoelectric detection counter in real time and updating the roll information, thereby improving the control accuracy and stability.

[0011] Furthermore, the roll information includes at least the roll diameter; step S3 includes: S31: Calculating the circumference of the roll according to the roll diameter; S32: Calculate the reel rotation speed according to the reel circumference and the unwinding linear speed.

[0012] The present application provides a PLC control method for unwinding an extra-large roll, which clarifies the specific calculation method of the roll speed, making the calculation of the roll speed more accurate and providing a reliable basis for subsequent motor control.

[0013] Furthermore, the motor drives the unwinder to operate via a gear component, wherein the gear component includes a small gear connected to the motor and a large gear meshing with the small gear; step S4 includes: S41: Obtain the motor reduction ratio and the first gear number of the large gear and the second gear number of the small gear; S42: Calculating the required motor speed according to the first gear number, the second gear number, the motor reduction ratio, and the drum speed; S43: Calculating the required frequency of the motor according to the required speed of the motor.

[0014] The present application provides a PLC control method for unwinding an extra-large roll, which refines the calculation process of the required speed and frequency of the motor and takes into account the reduction ratio of the gear components, making the motor control more precise and adaptable.

[0015] Furthermore, step S6 includes: S61: During the unwinding process of the unwinder, obtaining a first strapping height at the initial strapping time, and determining whether the first strapping height reaches the proximal end surface; S62: If the vehicle reaches the near end face, an end face warning message is issued and the user is reminded to reduce the motor speed; S63: Determine whether the end face unwinding is abnormal, if an abnormality occurs, control the unwinding machine to stop running, if no abnormality occurs, control the motor to run according to the reduced motor speed; S64: If the near end surface has not been reached, the reading of the photoelectric detection counter is obtained.

[0016] Furthermore, the roll information also includes roll height, strapping tape, and strapping tape thickness; step S7 includes: S71: Calculating the first number of turns of each layer of the strapping tape on the reel before unwinding according to the reel height and the strapping tape width; S72: Calculating in real time the number of second turns remaining in each layer of the strapping tape during the unwinding process based on the first number of turns and the reading; S73: Calculating the number of first layers of strapping tape on the roll before unwinding based on the roll diameter and the strapping tape thickness in the roll information, and calculating the number of second layers of strapping tape remaining during unwinding in real time based on the first number of layers, the first number of turns, and the reading; S74: Calculating in real time the second roll diameter remaining during the unwinding process based on the roll diameter of the roll before unwinding, the first number of turns, the reading, and the strapping tape thickness; The real-time updated information at least includes the second number of turns, the second number of layers, and the second roll diameter.

[0017] Furthermore, step S7 further includes: S75: Acquire the direction of the strapping tape being unwound, wherein the direction of the strapping tape being unwound includes the direction of the strapping tape being unwound from top to bottom and the direction of the strapping tape being unwound from bottom to top. S76: When the strapping tape is discharged from the top to the bottom, the real-time strapping tape discharge height is calculated based on the first strapping tape discharge height minus the product of the reading and the strapping tape width; S77: When the strapping tape is discharged in an upward direction, the real-time strapping tape discharge height is calculated based on the first strapping tape discharge height plus the product of the reading and the strapping tape width; The real-time update information also includes the real-time tape-out height.

[0018] In a second aspect, a PLC control device for unwinding an oversized roll is provided, for implementing any of the above methods, the device comprising: Judgment module: After the unwinding machine operation button is started, it determines whether the unwinding position of the reel on the unwinding machine is abnormal; Startup module: if there is no abnormality in the unwinding position of the reel, the unwinder is started and the reel information and unwinding speed of the strapping tape are obtained; A first calculation module is used to calculate the reel rotation speed according to the reel information and the unwinding line speed; The second calculation module is used to obtain the motor reduction ratio and calculate the required motor speed and motor frequency based on the drum speed. Control module: controls the operation of the motor according to the required speed and frequency of the motor, thereby controlling the unwinding of the unwinder.

[0019] According to a third aspect, an electronic device includes a processor and a memory, wherein the memory stores computer-readable instructions. When the computer-readable instructions are executed by the processor, the steps in the above method are executed.

[0020] In a fourth aspect, a computer-readable storage medium stores a computer program, which executes the steps of the above method when executed by a processor.

[0021] Beneficial effects: The PLC control method, device, electronic device and storage medium for unwinding super-large rolls provided in this application obtain the roll information and line speed in real time during the unwinding process, dynamically calculate the required speed and frequency of the motor, and perform closed-loop control, thereby effectively solving the problems of insufficient control accuracy and unstable operation caused by fixed parameters in the existing technology. It can thus achieve real-time, dynamic and precise control of the unwinding process of super-large rolls, effectively solve the problems of line speed fluctuations, tension loss of control, strip damage and unstable motor operation caused by fixed parameters in the existing technology, and significantly improve the safety, continuity and production efficiency of unwinding. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a workflow diagram of a PLC control method for unwinding an extra-large roll provided in this application.

[0023] Figure 2 This is a flow chart of a PLC control method for unwinding an extra-large roll provided in this application.

[0024] Figure 3 This is a structural schematic diagram of a PLC control device for unwinding an extra-large roll provided in this application.

[0025] Figure 4 This is a schematic diagram of the structure of the electronic device provided in this application.

[0026] Description of reference numerals: 201, judgment module; 202, startup module; 203, first calculation module; 204, second calculation module; 205, control module; 301, processor; 302, memory; 303, communication bus; 3, electronic device. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application generally described and marked in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work fall within the scope of protection of the present application.

[0028] It should be noted that similar reference numerals and letters represent similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined or explained in subsequent figures. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and should not be understood as indicating or implying relative importance.

[0029] Please refer to Figure 1 、 Figure 2 The present invention provides a PLC control method for unwinding an oversized roll, the method comprising the steps of: S1: After the unwinding machine operation button is turned on, determine whether the unwinding position of the reel on the unwinding machine is abnormal; S2: If there is no abnormality in the unwinding position of the reel, the unwinding machine is started and the reel information and unwinding speed of the strapping tape are obtained; S3: Calculate the reel speed based on the reel information and unwinding line speed; S4: Obtain the motor reduction ratio, and calculate the required motor speed and motor frequency based on the drum speed; S5: Control the motor operation according to the required speed and frequency of the motor, thereby controlling the unwinding of the unwinder.

[0030] Among them, the unwinding machine is provided with a turntable, the vertical super-large roll is arranged on the turntable, and the turntable is connected to the motor and driven by the motor to rotate and unwind.

[0031] In step S1, the unwinding position of the reel refers to the position of the reel on the turntable. Under normal circumstances, the turntable is provided with a boss mounting structure that matches the reel core. The reel core is mounted on this boss mounting structure, allowing the reel to be fixed on the turntable for rotation. If the reel is installed at an angle or is not mounted on the boss mounting structure, after the start button is turned on, the control system does not recognize the reel as being properly installed, and an unwinding position installation abnormality alarm is issued.

[0032] The unwinder's run button only means pressing the run button, and does not mean the unwinder starts normally. After the run button is pressed, if the unwinding position of the reel is recognized to be normal, the unwinder starts normally and obtains the strapping tape reel information and the strapping tape unwinding speed. Otherwise, the unwinder does not start and issues an alarm indicating an abnormal unwinding position installation.

[0033] The strapping tape roll information is obtained by scanning the QR code on the strapping tape. The roll information stored in the QR code includes but is not limited to the roll diameter, roll height, strapping tape thickness, and strapping tape width. The strapping tape unwinding speed refers to the desired linear movement speed of the strapping tape during the unwinding process. This speed can be set by the operator or obtained by the PLC control system command. It is mainly used to ensure that the strapping material is discharged at a constant speed.

[0034] The motor reduction ratio refers to the speed ratio of the gear components that transmit between the motor and the unwinder.

[0035] The core innovation of this application is to ensure initial safety by judging the abnormality of the unwinding position before the unwinding starts, and on this basis, based on the acquired strapping roll information and the expected unwinding line speed, combined with the motor reduction ratio, accurately calculate the required speed and frequency of the motor, thereby achieving accurate and stable control of the unwinding process of the oversized roll, effectively solving the problems in the prior art caused by inaccurate or fixed parameter estimation, leading to line speed fluctuations, tension loss of control and equipment emergency stop, and achieving the purpose of safe, continuous and accurate unwinding of oversized rolls.

[0036] Specifically, before starting the unwinder, this method begins by issuing an unwind command via the start button on the human-machine interface (HMI). Visual sensors or multiple photoelectric switch arrays installed at key locations on the unwinder scan or detect the unwinding position of the tape to determine whether the tape is correctly installed on the turntable. If the unwinding position is normal, the system starts the unwinder and simultaneously acquires the initial physical information of the current strapping tape roll and the preset unwinding linear speed. The precise acquisition of this initial data is the foundation for all subsequent dynamic calculations, ensuring real-time and accurate control. Subsequently, based on the acquired roll information and unwinding linear speed, the system accurately calculates the rotational speed required to maintain a constant linear speed. This calculation converts the required linear speed into a required rotational speed.

[0037] Next, the system obtains the motor's reduction ratio and, combined with the calculated roll speed, calculates the gear ratio to determine the precise speed and corresponding operating frequency required to achieve the target roll speed. This conversion process ensures that the motor output matches the actual needs of the unwinding mechanism.

[0038] Ultimately, the system commands the motor based on these precisely calculated required speed and frequency, causing it to operate according to these parameters, thereby achieving precise and stable control of the unwinding process of the unwinder, effectively avoiding line speed fluctuations and control instability caused by parameter mismatch in traditional solutions.

[0039] During this process, as the unwinder continuously unwinds, information such as the roll diameter, remaining layers, and number of coils will constantly change. If the control system relies solely on initially calculated parameters and lacks a real-time update mechanism, the motor control parameters will not match the actual roll state, leading to fluctuations in the unwinding line speed and uncontrolled tension, potentially causing the strapping tape to break or become stacked. Furthermore, if the motor's required frequency cannot be automatically adjusted based on the real-time roll diameter due to the changing unwinding diameter, it may also result in insufficient torque at low speeds or overspeed alarms at high speeds, causing the equipment to stop suddenly, impacting production efficiency and stability.

[0040] The low-speed stage refers to the initial stage of unwinding, when the roll diameter is still large. The drum speed (and motor speed) is very low, but the required tension (pulling force) of the strapping tape is very high. At this time, the motor must output sufficient torque to maintain constant tension; otherwise, the strapping tape will "fail" or "slip," a phenomenon known as insufficient torque in the low-speed stage.

[0041] The high-speed section refers to the period nearing the end of unwinding and when the roll diameter decreases. The reel must rotate at high speed to maintain a constant linear velocity (at this time, the motor speed is also very high). If the motor frequency does not automatically adjust as the roll diameter decreases, the motor may overspeed, triggering an "overspeed alarm," or resulting in insufficient output torque, causing tension to run out of control or tape breakage. This is called a high-speed section torque deficiency or overspeed alarm.

[0042] Therefore, in order to solve this problem, the method further includes the steps of: S6: During the unwinding process of the unwinder, the reading of the photoelectric detection counter is obtained in real time; S7: Calculate the real-time update information of the roll according to the reading and the roll information; S8: Calculate the real-time updated speed of the reel based on the real-time updated information and the unwinding line speed; S9: Calculate the required speed and frequency of the motor real-time update according to the motor reduction ratio and the real-time update speed of the reel; S10: controlling the motor operation according to the real-time updated required speed and the real-time updated required frequency of the motor, thereby controlling the unwinding of the unwinder.

[0043] Among them, the reading of the photoelectric detection counter reflects the number of turns of the reel unwinding.

[0044] The real-time update information of the roll refers to the roll status data obtained according to the actual unwinding amount during the unwinding process. It can be achieved by using parameters such as real-time diameter, remaining number of turns, remaining number of layers, and real-time roll height.

[0045] In one embodiment, the method can be implemented as follows: During unwinding, a photoelectric detection counter can be installed on the strapping tape's delivery path. For example, when the strapping tape passes a certain point, the counter generates a pulse signal each time the strapping tape passes that point. A PLC control system reads the pulse reading of the counter in real time, and this reading represents the number of strapping tape turns unwound.

[0046] Based on this real-time reading and initial roll information acquired at system startup (such as initial roll diameter and strap thickness), the PLC control system calculates real-time roll updates. Once the real-time roll updates, such as the real-time diameter, are obtained, the PLC control system combines this with the preset unwinding line speed (for example, maintaining a line speed of 20 meters per minute) to recalculate the real-time roll speed. For example, the real-time roll speed can be calculated by dividing the unwinding line speed by the real-time roll circumference (π * real-time roll diameter). Next, based on this real-time roll speed and the known motor reduction ratio, the PLC control system calculates the real-time required motor speed. For example, if the motor reduction ratio is 1:10 and the real-time roll speed is 10 RPM, the required motor speed is 100 RPM.

[0047] Based on this information, the PLC control system calculates the motor's real-time required speed based on the motor's real-time updated desired speed and other parameters, such as the motor's pole pair count. Finally, the PLC transmits these real-time required speed and frequency commands to the motor. Upon receiving these commands, the motor adjusts its output, thereby controlling the unwinder's operation, ensuring that the strapping tape is unwound at the set linear speed. This control is maintained even if the roll diameter changes during the unwinding process.

[0048] By introducing a mechanism that acquires real-time readings from a photoelectric detection counter, calculates real-time roll updates, and dynamically adjusts motor operating parameters accordingly, this application can address control accuracy issues caused by the continuous change in roll diameter during the unwinding of oversized rolls. This solution maintains the unwinding line speed and controls the strapping tension, preventing the strap from breaking or accumulating. Furthermore, because the required motor frequency can be automatically adjusted based on the real-time roll diameter, it solves the problems of insufficient torque in the low-speed range and overspeed alarms in the high-speed range, reduces the occurrence of equipment emergency stops, and improves production continuity and stability.

[0049] Furthermore, the roll information includes at least the roll diameter; step S3 includes: S31: Calculate the circumference of the roll according to the roll diameter; S32: Calculate the reel rotation speed according to the reel circumference and the unwinding linear speed.

[0050] The calculation formula for the roll circumference is: roll circumference = π*roll diameter.

[0051] The formula for calculating the reel speed is: reel speed = unwinding line speed / reel circumference.

[0052] This method provides clear input for subsequent precise calculations by clarifying that the roll information includes the roll diameter, avoiding calculation deviations caused by incomplete or unclear roll information. On this basis, the calculation of the roll speed is refined into two sub-steps. First, based on the obtained roll diameter, the roll circumference of the roll can be accurately calculated. This step is the key link between the roll diameter and the linear speed, laying an accurate foundation for the subsequent speed calculation. Secondly, after obtaining the accurate roll circumference, combined with the real-time unwinding line speed, the actual speed of the current roll can be accurately deduced based on the physical relationship between the linear speed, circumference and speed. It is precisely because of this calculation method based on real-time roll diameter and unwinding line speed that the calculation of the roll speed is closer to the actual operating status, avoiding the errors caused by the use of fixed roll diameter or table lookup estimation in traditional methods.

[0053] Furthermore, the motor drives the unwinder to operate through a gear component, wherein the gear component includes a small gear connected to the motor and a large gear meshing with the small gear; step S4 includes: S41: Obtain the motor reduction ratio and the first gear number of the large gear and the second gear number of the small gear; S42: Calculating the required motor speed according to the first gear number, the second gear number, the motor reduction ratio, and the drum speed; S43: Calculate the required frequency of the motor according to the required speed of the motor.

[0054] Among them, the gear component refers to a mechanical transmission device used to transmit power and change the direction or speed of movement, including a small gear connected to the motor, which is the driving wheel, and a large gear connected to the turntable, which is the driven wheel. The small gear and the large gear are engaged to transmit power.

[0055] The formula for calculating the required motor speed is: Required motor speed = drum speed * (number of first gears / number of second gears) * motor reduction ratio. This formula is based on the classic mechanical transmission law that "speed is inversely proportional to the number of teeth and directly proportional to the reduction ratio." It is derived step by step in three levels: The first level: the speed ratio relationship between large and small gears.

[0056] Assume the pinion (driving gear) has Z2 teeth and the gear (driven gear) has Z1 teeth. For an external gear pair, the speed of each gear is inversely proportional to the number of teeth: n2 / n1 = Z1 / Z2. Where n2 is the pinion speed and n1 is the gear speed. Therefore, the pinion speed n2 = n1*(Z1 / Z2).

[0057] The second layer: introduce the motor reduction ratio i.

[0058] The motor's output shaft first passes through a speed reducer (with a speed ratio of i) before driving the pinion. The relationship between the motor's required speed, n, and the speed of the speed reducer's output shaft (i.e., the pinion), n2, is: n2 = n / i. Substituting this into the above formula for the pinion's speed yields: n / i = n1*(Z1 / Z2). This derives the motor's required speed as: n = n1*(Z1 / Z2)*i.

[0059] The third layer: introduce the reel speed nr.

[0060] In this device, the gear and the turntable (drum) are coaxial, so the drum speed nr is equal to the gear speed n1. The resulting motor speed is: n = nr * (Z1 / Z2) * i, meaning required motor speed = drum speed * (number of first gears / number of second gears) * motor reduction ratio.

[0061] Once the motor's required speed is accurately calculated, the PLC control system can convert it into the required frequency based on the motor type and its electrical characteristics. Specifically, the formula for calculating the motor's required frequency is: Required Motor Frequency = (Required Motor Speed ​​ / Standard Speed ​​1450 RPM) * 50 Hz.

[0062] This application significantly improves the accuracy of the calculation by incorporating detailed parameter considerations of the gear components in the specific mechanical transmission structure between the motor and the unwinder into the calculation of the required motor speed and frequency. This precise calculation ensures that the motor output speed and frequency closely match the actual speed required by the unwinder, thereby enabling precise control of the unwinder. Therefore, this application effectively addresses the control accuracy issues inherent in traditional solutions due to insufficient consideration of transmission details, avoids operational instabilities such as insufficient torque at low speeds and overspeed alarms at high speeds, and significantly improves the stability and production efficiency of the unwinding process.

[0063] Furthermore, step S6 includes: S61: During the unwinding process of the unwinder, a first strip-out height of the strapping tape at the initial strip-out moment is obtained, and it is determined whether the first strip-out height reaches the near-end surface; S62: If the vehicle reaches the near end face, an end face warning message is issued and the user is reminded to reduce the motor speed; S63: Determine whether the end face unwinding is abnormal. If an abnormality occurs, control the unwinding machine to stop running. If no abnormality occurs, control the motor to run according to the reduced motor speed. S64: If the near end surface has not been reached, the reading of the photoelectric detection counter is obtained.

[0064] The near-end surface refers to the upper and lower end surfaces of the roll. The near-end surface refers to the critical state or area where the strapping tape is about to be completely separated from the roll in the height direction during the unwinding process. It is usually defined by a preset strapping height threshold. The end-face warning information refers to the prompt information sent by the system to the user when it determines that the strapping tape has reached the near-end surface. This can be achieved through audio and visual alarms, screen displays, communication signal transmission, etc.

[0065] Whether the end face unwinding is abnormal refers to the system's real-time monitoring and judgment of the unwinding status when the strapping tape is unwound to the near end face, to determine whether the strapping tape has abnormal conditions such as side rolling, position deviation, and loose tape at the near end face.

[0066] This solution effectively addresses the safety and stability issues that may arise at the end of unwinding an oversized roll by predicting and addressing the near-end surface of the strapping tape during the unwinding process, ensuring a smooth transition and continuity during the unwinding process. Specifically, during the operation of the unwinder, the first tape outlet height at the initial tape outlet moment is obtained, and this is used to determine whether the strapping tape has reached the near-end surface. This predictive mechanism is the core of the entire solution, and it compensates for the lack of early warning of the end of the roll in the existing technology. Once it is determined that the near-end surface has been reached, the system will immediately issue a warning message and remind the user to reduce the motor speed. This provides the operator with an opportunity to intervene in a timely manner and effectively reduces the risk of unwinding at the end through deceleration.

[0067] The system then continuously monitors the end face for any anomalies in the unwinding process. If any are detected, the unwinder is immediately stopped, providing a high level of safety that effectively prevents equipment damage or personal injury. If no anomalies are detected, the motor continues to operate at the reduced speed, ensuring a smooth transition. If the strapping tape has not yet reached the near end face, the system continues with the normal operation of acquiring the photoelectric detection counter reading, ensuring continuous data acquisition and control accuracy during the normal unwinding phase.

[0068] In this way, this solution, based on the existing real-time acquisition of photoelectric detection counter readings, adds refined management of the unwinding end. This not only maintains high-precision control throughout the unwinding process during the normal phase, but also provides the necessary safety guarantees and a smooth transition mechanism during the critical end phase. This, combined with the previous solution's overall control logic that uses photoelectric detection counter readings to update reel information in real time and adjust motor operation, ensures greater safety, stability, and continuity throughout the life cycle of the oversized roll unwinding control system, avoiding sudden failures and production interruptions caused by the roll approaching the end.

[0069] Furthermore, the roll information also includes roll height, strapping tape width, and strapping tape thickness; step S7 includes: S71: Calculate the first number of turns of each layer of the strapping tape on the reel before unwinding according to the reel height and the strapping tape width; S72: Calculate the remaining second turns of each layer of the strapping tape during the unwinding process in real time based on the first turn number and the reading; S73: Calculating the number of first layers of strapping tape on the roll before unwinding based on the roll diameter and strapping tape thickness in the roll information, and calculating the number of second layers of strapping tape remaining during unwinding in real time based on the first layer number, the first number of turns, and the reading; S74: Calculating in real time the second roll diameter remaining during the unwinding process based on the roll diameter, the first number of turns, the reading, and the strapping tape thickness of the roll before unwinding; The real-time updated information includes at least the second number of turns, the second number of layers, and the second roll diameter.

[0070] The calculation formula for the first number of turns is: first number of turns = reel height / strapping tape width, which means that the total height of the strapping tape on the reel is divided by the width of the strapping tape to get the total number of first turns of the strapping tape in each layer on the reel.

[0071] The second number of turns indicates the remaining number of turns in each layer during the unwinding process. The reading of the photoelectric detection counter indicates the number of turns that have been unwound. The first number of turns is the total number of turns in each layer. The remaining number of turns in each layer is obtained by subtracting the number of turns that have been unwound from the total number of turns, that is: the second number of turns = the first number of turns - the reading.

[0072] Subtract the core diameter of the roll from the roll diameter, divide by the thickness of the strapping tape and divide by 2 to get the total number of first layers of strapping tape wrapped around the roll.

[0073] After obtaining the first number of layers, the remaining number of layers is calculated by subtracting the ratio of the number of unwound coils to the total number of coils per layer from the first number of layers. This remaining number of layers is the second number of layers. When the ratio of the number of unwound coils to the total number of coils per layer (reading / first number of coils) is less than 1, the integer part of the decimal less than 1 is subtracted from the first number of layers, which is equivalent to subtracting one. For example, if the first number of layers is 10, the integer part of the decimal less than 1 is 9, which means that the layer currently being unwound is the 10th layer on the outermost side of the roll, and there are 9 layers remaining (the second number of layers).

[0074] When the ratio of the reading to the first number of turns is an integer or decimal greater than 1, the principle for calculating the remaining second layers is the same as above. For example, when the ratio of the reading to the first number of turns is 1.1, 10-1.1=8.9, the integer part of which is 8, the remaining second layers are 8, and the layer currently being unwound is the 9th layer.

[0075] The total thickness of the unwound strapping tape can be obtained by multiplying the ratio of the reading to the first number of turns by the thickness of the strapping tape. Then, the second roll diameter remaining in the unwound process can be calculated in real time by subtracting the total thickness of the unwound strapping tape from the roll diameter before unwound. Therefore, the calculation formula for the second roll diameter is: second roll diameter = roll diameter - (reading / first number of turns) * strapping tape thickness.

[0076] Through the above series of precise calculations, this method can generate real-time update information including the second number of turns, the second number of layers and the second roll diameter in real time. This information is input into the subsequent control logic as a comprehensive and accurate description of the unwinding status of the super-large roll. For example, when calculating the real-time update speed of the roll, the system will use these precise real-time update information instead of relying on rough estimates. Subsequently, based on the motor reduction ratio and the real-time update speed of the roll, the system can calculate the required speed and frequency for the real-time update of the motor, and accurately control the operation of the motor accordingly, thereby achieving refined and closed-loop control of the unwinding process of the unwinder. This interlocking precise calculation and real-time feedback mechanism enables the system to continuously adapt to the dynamic changes in the roll diameter, ensure the stability of the unwinding line speed and the accuracy of the tension control, and effectively avoid the problems of line speed fluctuations and tension out of control caused by inaccurate roll diameter estimation.

[0077] The above method allows for dynamic adjustment of unwinding parameters based on changes in the radial dimensions of the roll, thereby improving unwinding stability and accuracy. However, during its implementation, for vertical oversized rolls, the real-time vertical position information of the strapping tape is not effectively captured and incorporated into the real-time update mechanism. This lack of information prevents the control system from understanding the actual unwinding status of the strapping tape, potentially leading to inaccurate vertical position control during the unwinding process. This can cause problems such as strapping stacking, deviation, or tension fluctuations, impacting the stability and accuracy of oversized roll unwinding.

[0078] Therefore, in order to solve this problem, step S7 further includes: S75: Acquire the direction of the strapping tape during the unwinding process, where the strapping tape can be discharged from top to bottom or from bottom to top. S76: When the strapping direction is from top to bottom, the real-time strapping height is calculated based on the first strapping height minus the product of the reading and the strapping width; S77: When the strapping direction is from bottom to top, the real-time strapping height is calculated based on the first strapping height plus the product of the reading and the strapping width; The real-time updated information also includes the real-time belt height.

[0079] This solution not only updates the radial information of the reel in real time, but also introduces real-time monitoring and updating of the strapping tape's vertical position. Specifically, during the unwinder's operation, the system first obtains the strapping tape's exit direction, ensuring consistency between the calculation logic and the actual physical movement direction.

[0080] When the system determines that the strapping is unwinding from top to bottom, the strapping exit point gradually lowers as the unwinding progresses. At this point, the system subtracts the accumulated reading of the photoelectric detection counter multiplied by the strapping width from the initial unwinding height. The product of the photoelectric detection counter reading and the strapping width accurately quantifies the vertical distance the strap has been unwound. By deducting this distance from the initial height, the current real-time strapping height can be accurately determined.

[0081] Conversely, when the tape is unwound from bottom to top, the tape's exit point will gradually rise as it unwinds. In this case, the system adds the accumulated reading of the photoelectric detection counter and the tape width to the initial exit height. This product represents the vertical distance the tape has been unwound. By adding this value to the initial height, the current, real-time exit height of the tape can be accurately determined.

[0082] Through this approach, the system accurately and in real time determines the vertical exit position of the strapping tape, regardless of whether the tape is unwinding upward or downward. This real-time exit height, combined with previously acquired and updated radial roll information (such as the number of turns, layers, and diameter), is incorporated into the real-time update, enabling the PLC control system to obtain comprehensive three-dimensional information about the tape's unwinding status. This comprehensive, real-time feedback enables the PLC control system to adjust unwinding parameters not only based on changes in the roll's radial dimensions, but also to precisely adjust to changes in the tape's vertical position. For example, if the real-time exit height deviates from a preset range, the PLC can issue commands to adjust the unwinder's vertical guide mechanism or tension control, effectively preventing problems such as stacking, deviation, or tension fluctuations during the unwinding process. This integrated, real-time update and control of both radial and vertical information improves the stability and accuracy of oversized roll unwinding, ensuring smooth and orderly unwinding of the strapping tape.

[0083] Please refer to Figure 3 The present application provides a PLC control device for unwinding an oversized roll, for implementing any of the methods, the device comprising: Determination module 201: after the unwinding machine operation button is activated, determine whether the unwinding position of the reel on the unwinding machine is abnormal; Start module 202: If there is no abnormality in the unwinding position of the reel, the unwinding machine is started and the reel information and the unwinding speed of the strapping tape are obtained; The first calculation module 203 calculates the reel rotation speed according to the reel information and the unwinding line speed; The second calculation module 204 obtains the motor reduction ratio and calculates the required motor speed and motor frequency based on the drum speed; Control module 205: controls the motor to run according to the required speed and frequency of the motor, thereby controlling the unwinding of the unwinder.

[0084] The judgment module 201 refers to a unit for executing a logic judgment function, which can be implemented by a specific program segment in a programmable logic controller (PLC), a logic circuit in a microcontroller (MCU) or an application-specific integrated circuit (ASIC).

[0085] The startup module 202 is a unit for initializing the operation of the device and acquiring initial data. The startup module 202 can be implemented by using a PLC output to control a relay or contactor in combination with a sensor data acquisition interface.

[0086] The first calculation module 203 refers to a unit for performing initial data calculation, which can be implemented by using a PLC arithmetic operation instruction set, a digital signal processor (DSP), or a general-purpose processor (CPU).

[0087] The second calculation module 204 refers to a unit for performing further data calculations, which can be implemented using similar calculation hardware as the first calculation module, such as an arithmetic operation unit of a PLC or an embedded processor.

[0088] The control module 205 is a unit for outputting a control signal to drive an actuator according to a calculation result, and can be implemented by using a PLC analog output module, a pulse output module or a frequency converter drive interface.

[0089] The overall operational logic of this solution is to decompose the complex control method for unwinding oversized rolls into a series of interoperable functional modules, thereby achieving an automated, precise, and stable unwinding process. Specifically, when the unwinder operation button is activated, the judgment module 201 is first involved. Its core function is to serve as the first checkpoint for safety and correctness. By initially determining the unwinding position of the strapping tape, it can promptly detect and avoid potential abnormalities, laying a safe foundation for subsequent precise control.

[0090] Once it is confirmed that there is no abnormality in the unwinding position, the starting module 202 is activated. It is not only responsible for starting the physical operation of the unwinder, but more importantly, it synchronously obtains the initial roll information of the strapping tape and the preset unwinding line speed. These data are the cornerstones of the entire control system for accurate calculations.

[0091] Subsequently, the first calculation module 203 receives this basic data and, based on the roll information and the unwinding line speed, accurately calculates the current roll's required rotational speed. This is a key step in achieving constant line speed unwinding, ensuring that the line speed remains stable even when the roll diameter is constantly changing. Next, the second calculation module 204, based on the motor reduction ratio and combined with the roll rotational speed output by the first calculation module 203, further converts the mechanical motion requirements into electrical parameters that the motor can recognize and execute, namely the motor's required rotational speed and frequency, thereby ensuring that the motor can accurately respond to the roll's rotational speed requirements.

[0092] Ultimately, the control module 205, as the execution core of the entire system, precisely drives the motor according to the required motor speed and frequency provided by the second calculation module, thereby achieving stable, continuous, and precise unwinding of the unwinder. It is precisely through this modular device design that the present solution is able to systematically carry and execute the complex calculations and real-time adjustment steps proposed in previous methods. The close cooperation between the judgment module 201, the startup module 202, the first calculation module 203, the second calculation module 204, and the control module 205 enables the initial judgment, data acquisition, multi-level calculation, and final motor drive in the method to be automated and precise. For example, the steps of obtaining the reading of the photoelectric detection counter in real time, calculating the real-time update information of the reel, and dynamically adjusting the motor speed and frequency based on this information can all be efficiently implemented through the collaborative work of these functional modules. This combination of device and method ensures that problems such as line speed fluctuation and tension loss can be effectively suppressed during the unwinding process of super-large rolls, the risk of strip breakage or stacking is significantly reduced, and the frequency of equipment emergency stops is also greatly reduced, thereby significantly improving the continuity and efficiency of production.

[0093] Please refer to Figure 4 , Figure 4This is a structural schematic diagram of an electronic device provided in an embodiment of the present application. The present application provides an electronic device 3, including: a processor 301 and a memory 302. The processor 301 and the memory 302 are interconnected and communicate with each other through a communication bus 303 and / or other forms of connection mechanisms (not shown). The memory 302 stores computer-readable instructions executable by the processor 301. When the electronic device is running, the processor 301 executes the computer-readable instructions to execute the method in any optional implementation of the above embodiment to achieve the following functions: after starting the unwinder operation button, determine whether the unwinding position of the reel on the unwinder is abnormal; if the unwinding position of the reel is normal, start the unwinder and obtain the reel information of the strapping tape and the unwinding linear speed of the strapping tape; calculate the reel speed based on the reel information and the unwinding linear speed; obtain the motor reduction ratio, and calculate the required motor speed and motor frequency in combination with the reel speed; control the motor operation according to the required motor speed and the required motor frequency, thereby controlling the unwinding of the unwinder.

[0094] An embodiment of the present application provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the method in any optional implementation of the above embodiment is executed to achieve the following functions: after starting the unwinder operation button, determine whether the unwinding position of the reel on the unwinder is abnormal; if the unwinding position of the reel is normal, start the unwinder and obtain the reel information of the strapping tape and the unwinding linear speed of the strapping tape; calculate the reel speed based on the reel information and the unwinding linear speed; obtain the motor reduction ratio, and calculate the required motor speed and the required motor frequency in combination with the reel speed; control the motor operation based on the required motor speed and the required motor frequency, thereby controlling the unwinding of the unwinder.

[0095] The computer-readable storage medium may be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk or optical disk.

[0096] In the embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interface, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0097] In addition, the units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0098] Furthermore, the functional modules in each embodiment of the present application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0099] In this document, relational terms such as first and second, etc. are used merely to distinguish one entity or operation from another entity or operation, but do not necessarily require or imply any actual relationship or order between these entities or operations.

[0100] The above description is merely an embodiment of the present application and is not intended to limit the scope of protection of the present application. For those skilled in the art, various modifications and variations of the present application are possible. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A PLC control method for unwinding an extra-large roll, characterized in that: The method comprises the steps of: S1: After the unwinding machine operation button is turned on, determine whether the unwinding position of the reel on the unwinding machine is abnormal; S2: If there is no abnormality in the unwinding position of the reel, start the unwinding machine and obtain the reel information of the strapping tape and the unwinding speed of the strapping tape; S3: Calculating the reel rotation speed according to the reel information and the unwinding line speed; S4: Obtaining the motor reduction ratio, and calculating the required motor speed and motor frequency in combination with the drum speed; S5: controlling the motor to operate according to the required speed and frequency of the motor, thereby controlling the unwinding machine to unwind.

2. A PLC control method for unwinding a super-large roll according to claim 1, characterized in that: The method further comprises the steps of: S6: During the unwinding process of the unwinding machine, a reading of a photoelectric detection counter is obtained in real time; S7: Calculating real-time updated information of the reel based on the reading and the reel information; S8: Calculating the real-time updated rotation speed of the reel according to the real-time updated information and the unwinding line speed; S9: Calculating the required speed and frequency of the motor for real-time update according to the motor reduction ratio and the real-time update speed of the reel; S10: controlling the operation of the motor according to the real-time updated required speed of the motor and the real-time updated required frequency of the motor, thereby controlling the unwinding of the unwinder.

3. The PLC control method for unwinding a super-large roll according to claim 1, characterized in that: The roll information includes at least the roll diameter; step S3 includes: S31: Calculating the circumference of the roll according to the roll diameter; S32: Calculate the reel rotation speed according to the reel circumference and the unwinding linear speed.

4. The PLC control method for unwinding a super-large roll according to claim 3 is characterized in that: The motor drives the unwinder to operate via a gear component, wherein the gear component includes a small gear connected to the motor and a large gear meshing with the small gear; step S4 includes: S41: Obtain the motor reduction ratio and the first gear number of the large gear and the second gear number of the small gear; S42: Calculating the required motor speed according to the first gear number, the second gear number, the motor reduction ratio, and the drum speed; S43: Calculating the required frequency of the motor according to the required speed of the motor.

5. The PLC control method for unwinding a super-large roll according to claim 2, characterized in that: Step S6 includes: S61: During the unwinding process of the unwinder, obtaining a first strapping height at the initial strapping time, and determining whether the first strapping height reaches the proximal end surface; S62: If the vehicle reaches the near end face, an end face warning message is issued and the user is reminded to reduce the motor speed; S63: Determine whether the end face unwinding is abnormal, if an abnormality occurs, control the unwinding machine to stop running, if no abnormality occurs, control the motor to run according to the reduced motor speed; S64: If the near end surface has not been reached, the reading of the photoelectric detection counter is obtained.

6. The PLC control method for unwinding a super-large roll according to claim 2, characterized in that: The roll information also includes roll height, strapping tape width and strapping tape thickness; step S7 includes: S71: Calculating the first number of turns of each layer of the strapping tape on the reel before unwinding according to the reel height and the strapping tape width; S72: Calculating in real time the number of second turns remaining in each layer of the strapping tape during the unwinding process based on the first number of turns and the reading; S73: Calculating the number of first layers of strapping tape on the roll before unwinding based on the roll diameter and the strapping tape thickness in the roll information, and calculating the number of second layers of strapping tape remaining during unwinding in real time based on the first number of layers, the first number of turns, and the reading; S74: Calculating in real time the second roll diameter remaining during the unwinding process based on the roll diameter of the roll before unwinding, the first number of turns, the reading, and the strapping tape thickness; The real-time updated information at least includes the second number of turns, the second number of layers, and the second roll diameter.

7. A PLC control method for unwinding a super-large roll according to claim 6, characterized in that: Step S7 further includes: S75: Acquire the direction of the strapping tape being unwound, wherein the direction of the strapping tape being unwound includes the direction of the strapping tape being unwound from top to bottom and the direction of the strapping tape being unwound from bottom to top. S76: When the strapping tape is discharged from the top to the bottom, the real-time strapping tape discharge height is calculated based on the first strapping tape discharge height minus the product of the reading and the strapping tape width; S77: When the strapping tape is discharged in an upward direction, the real-time strapping tape discharge height is calculated based on the first strapping tape discharge height plus the product of the reading and the strapping tape width; The real-time update information also includes the real-time tape-out height.

8. A PLC control device for unwinding an extra-large roll, characterized in that: For implementing the method according to any one of claims 1 to 7, the device comprises: Judgment module: After the unwinding machine operation button is started, it determines whether the unwinding position of the reel on the unwinding machine is abnormal; Startup module: if there is no abnormality in the unwinding position of the reel, the unwinder is started and the reel information and unwinding speed of the strapping tape are obtained; A first calculation module is used to calculate the reel rotation speed according to the reel information and the unwinding line speed; The second calculation module is used to obtain the motor reduction ratio and calculate the required motor speed and motor frequency based on the drum speed. Control module: controls the operation of the motor according to the required speed and frequency of the motor, thereby controlling the unwinding of the unwinder.

9. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores computer-readable instructions. When the computer-readable instructions are executed by the processor, the steps of the method according to any one of claims 1 to 7 are executed.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are executed.

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