Film coiling machine and application thereof

Abstract

The invention relates to the field of plastic film production equipment, in particular to a film coiling machine and application thereof, and more particularly relates to a film coiling method on two-way stretch film equipment. The thin film coiling machine comprises a conveying module and a coiling module, the conveying module is adjacent to the coiling module, the conveying module comprises a tension roller and a contact roller, and the conveying module is used for conveying a thin film to the coiling module; the winding module comprises a winding roller and is used for continuously winding the thin film. According to the thin film winding method, the limiting torque of a winding roller motor is jointly influenced by various parameters, accurate measurement and calculation of the parameters provide an accurate control means for two-way stretching, and the formula tension, the real-time winding diameter of the winding roller, the acceleration and deceleration compensation torque, the friction torque of the winding roller and the PID compensation torque act synergistically, so that the two-way stretching precision is improved. And the motor can respond to the tension requirement of the film in real time in the two-way stretching process.

Description

Technical Field

[0001] The invention relates to the field of plastic film production equipment, in particular to a film winding machine and application thereof, and more specifically to a film winding method on a biaxially stretched film device. Background Art

[0002] The winding in the known technology mostly adopts open loop or simple PID tension closed loop control. The open loop control tension accuracy is poor. The simple tension closed loop is prone to tension oscillation when the system is disturbed, and the recovery time is long. In extreme cases, it may cause the film to break. During the film winding, especially the initial winding, speed-up and roll changing stages of the film with a thickness of <20μm, the winding tension is not well controlled, which may easily cause the film roll to wrinkle, loosen or even break.

[0003] CN112573268A provides a plastic film winder, which effectively improves the film winding tension and improves product quality by adding a double-wire winding and flattening roller between the bending and flattening guide roller and the tension transmission roller. However, in different stages of biaxial stretching (such as initial stretching, rapid stretching and stretching balance stage), it lacks a dynamic adjustment mechanism for the winding tension. The tension requirements for each stage of biaxial stretching are different. During the initial stretching, a small and stable tension is required to guide the film into the stretching state. During the rapid stretching stage, the tension increase rate needs to be precisely controlled to achieve uniform stretching. During the stretching balance stage, a constant tension must be maintained to prevent the film from shrinking. This technology cannot adjust the tension in real time according to these stage changes, which limits the optimization of the effect of biaxial stretching.

[0004] CN116138096B provides a plastic film winding device, which, when idle, has a film positioning mechanism and a winding mechanism that are combined and mounted for easy movement and transportation, a cleaning component that can adjust the inclination angle and clean the film to ensure light transmittance, a film positioning mechanism that can prevent the tail end from damaging the seedlings and debris from falling and damaging the seedlings, and can also guide the debris into the receiving box. However, there are still some areas that need to be improved, for example, the winding roller may have inconsistent winding tightness due to uneven film thickness during the winding process; the versatility of the device may be insufficient for films of different widths and materials; the winding speed may be relatively fixed and cannot meet different production requirements, and the uneven thickness caused by stretching cannot be effectively dealt with during winding, affecting the quality of the film roll, and its fixed winding speed and limited versatility also make it difficult to meet the diverse process requirements during biaxial stretching. Summary of the invention

[0005] The present invention provides a film winder to solve the technical problems existing in the known technology. The film winder is aimed at film winding, especially the film winding with a thickness of less than 20 μm. The film winder is improved for the problem that the film roll is easily wrinkled, loose or even broken due to the poor control of the winding tension in the initial winding stage, the speed-up stage and the roll-changing stage. The winding tension of ordinary winding in the non-steady-state process such as the initial winding, speed-up and roll-changing is mainly processed to realize the constant tension winding of the film to avoid the problem of wrinkling, loosening or even broken film. The specific technical scheme is as follows: A film winding machine, comprising a transmission module and a winding module, wherein the transmission module is arranged adjacent to the winding module. The conveying module comprises a tension roller 1 and a contact roller 2, and the conveying module is used to convey the film 4 to the winding module; The winding module includes a winding roller 31 and a winding roller 32. The winding roller 31 is located at station A, which is close to the contact roller 2. The winding roller 32 is located at station B, which is far away from the contact roller 2. The winding module is used to continuously wind the film 4.

[0006] Furthermore, in the conveying module, the tension roller 1 is located at the far end of the winding module compared to the contact roller 2, and the contact roller 2 is located at the proximal end of the winding module compared to the tension roller 1. The tension roller 1 is used to measure the film tension in real time, and the contact roller 2 is close to the winding roller 31 or pressed on the winding roller when winding the film.

[0007] A method for winding a film using the film winding machine is characterized by comprising the following steps: S1 conveyor film The contact roller 2 is moved to the waiting position, and the film 4 is manually pulled through the tension roller 1 and the contact roller 2 to the winding roller 32 located at the station B, and the winding starts to accelerate to the set speed; S2: Film winding The winding roller 32 winds up a section of waste material and cuts the film, and then winds the film 4 onto the winding roller 31 on the A station, and starts to enter the normal winding mode; S3: Change roll When the winding roller 31 on the A station reaches full roll, it switches clockwise to the B station, cuts the film, takes down the full roll of film, and repeats the operation of S1. Thereafter, the above steps are repeated every time the winding length reaches full roll until the winding is completed or the machine stops unexpectedly.

[0008] Furthermore, the film winding method is divided into two methods: gap winding and contact winding.

[0009] Furthermore, the gap winding is that the contact roller 2 moves in real time with the change of the thickness of the winding material to maintain the set gap distance, the tension roller 1 runs at a constant speed during the entire winding process, the contact roller 2 adopts the positioning control mode, and the winding roller 31 adopts the speed control + torque limit control; Furthermore, the contact winding is that the contact roller 2 presses on the winding material according to the set pressure of the formula, the tension roller 1 runs at a constant speed during the entire winding process, the contact roller 2 adopts the torque control mode, and the winding roller 31 adopts the speed control + torque limit control mode.

[0010] Further, the speed control is controlled by the winding speed, and the torque limit control is controlled by the winding roller motor torque limit control.

[0011] Furthermore, the setting range of the formula tension of the winding film is 100-1000N, and the given value of the formula tension decreases linearly from small to large according to the real-time winding diameter.

[0012] Furthermore, the winding roller motor limiting torque is jointly affected by the formula tension, the real-time winding diameter of the winding roller, the acceleration and deceleration compensation torque, the winding roller friction torque, and the PID compensation torque.

[0013] Furthermore, the control of the limiting torque of the winding roller motor is divided into stable winding condition, winding acceleration and deceleration stage condition, and switching station winding condition according to different winding conditions: ① Under stable winding conditions, set the winding speed v 1= k · v 0, where k is the speed coefficient. In order to make the coiling saturate quickly, generally k The value is 1.05-1.1, v 0 is the production line speed, which is set manually; Winding roller motor limit torque M 1=1 / 2 F · D 1+ M f + M x ,in F Set the tension for the film, manually set, D 1 is the real-time winding diameter of the winding roller, which can be measured by the sensor; M f It is the friction torque of the winding roller, which can be directly read by the frequency converter of the film winding machine. M x It is the PID compensation torque; ② In the winding acceleration and deceleration stage, set the winding speed v 1= k· v 0, k The value is 1.05-1.1; Winding roller motor limit torque M 1=1 / 2 F · D 1+ M ad + M f + M x ,in, M ad To compensate the torque for acceleration and deceleration; ③ When switching the winding position, set the winding speed v 1= k ·( v 0- v 2), where v 2 is the compensation speed, k The value is 1.05-1.1; Winding roller motor limit torque M 1=1 / 2 F · D 1+ M f + M x .

[0014] The present invention adopts the actual measurement method to obtain M f , specific M f The measurement method is as follows: S1, contact roller gap winding mode M f The calculation steps are as shown in the instruction manual. Figure 2 As shown; in, n sv The actual running speed of the motor can be read directly from the driver. n max is the rated speed of the motor, i is the number of measurements that have been made, c is the total number of measurements required, c Any value can be taken, generally 10-20 is more appropriate. c =10, M sp Set the torque for the motor, which is manually adjusted during operation. n sv = n max · i / c, that is, when the actual running speed of the motor reaches the expected speed and remains constant, M sp = M f , thus recorded i =1, 2, 3, ..., c 10 groups M f The measurement results are saved in the form of a table. In the actual winding process, according to the actual working conditions of the contact roller, the corresponding M f .

[0015] S2, contact roller contact winding mode M f The calculation steps are as shown in the instruction manual. Figure 3 As shown; in, F r The contact roller pressure is manually adjusted during operation. F max The maximum set pressure of the contact roller, i For each contact roller pressure the number of measurements has been j is the number of contact roller pressure groups that have been measured, c 0 is the number of contact roller pressure groups to be measured, c 0 can take any value, generally 10-20 is more appropriate. c 0=10, c The number of measurements of friction torque for each set pressure of the contact roller, c Any value can be taken, but generally 10-20 is more appropriate. c =10, M sp Set the torque for the motor, which is set manually in actual operation; in the contact roller gap winding mode M f The calculation steps are the same as n sv = n max · i / c , that is, when the actual running speed of the motor reaches the expected speed and remains constant, M sp = M f , thus recorded i =1, 2, 3, ..., c 10 groups M f The measurement results are saved in the form of a table. In the actual winding process, according to the actual working conditions of the contact roller, the correspondingM f .

[0016] Acceleration and deceleration torque M ad The calculation of is as follows: M ad =2 V diff ·( J 0+ J 1) / ( D 1. t ),in, t is the acceleration and deceleration time, V diff is the speed change value, J 0 is the moment of inertia of the take-up system, which can be directly read through the self-tuning function of the take-up drive. J 1 is the moment of inertia of the film, which can be obtained according to the material and roll diameter of the film; PID compensation torque M x The calculation is as follows: M x = k p ( F pv F )+1 / k t ,in, k p It is the tension closed loop ratio, which is set manually during operation. F pv The real-time tension of the winding is measured by the tension roller 1 in real time. F It is the formula tension, which is set manually during operation. k t It is the tension closed loop integration time, which is set manually during operation; v 2 is calculated as follows: v 2= oh ·( L + D 1 / 2) / 2·sin ϴ ,in, oh The rotation speed for the coiling station switching is set manually during operation. L is the distance between the two winding rollers, obtained from the film winding machine's own parameters, ϴ The angle of the winding roller is read directly by the drive; The beneficial effects of the present invention are as follows: 1. The stability of the coiling process is significantly improved The present invention realizes stable control of the tension during the film winding process through a series of parameter adjustments. During the entire winding process, whether it is normal winding, acceleration and deceleration, or station switching, the tension of the film can be maintained within a reasonable range, effectively avoiding the influence of tension fluctuations on the winding quality, making the film roll smoother, reducing the occurrence of defects such as wrinkles and sagging, greatly improving the stability of the winding process, and laying the foundation for high-quality film production; 2. Enhanced equipment adaptability and versatility The present invention has excellent adaptability to films of different materials and thicknesses and various complex winding conditions. By optimizing the control mode and adjusting the parameters flexibly, the equipment can quickly respond to different production needs. For example, the limiting torque of the winding roller motor is affected by multiple parameters, among which the friction torque of the winding roller is M f The records help to adjust the motor output torque according to the actual situation of the film. When processing different types of films, the equipment can adapt quickly, improve the compatibility with diversified products, play a role in a wider range of production scenarios, and enhance the versatility and market competitiveness of the equipment; 3. The incidence of accidents is effectively reduced Precise parameter adjustment and stable tension control significantly reduce the probability of unexpected situations such as film breakage. In film production, film breakage not only causes waste of raw materials, but also interrupts production, affecting production efficiency and costs. The present invention effectively solves this problem, improves the continuity and stability of the production process, ensures efficient and smooth production, reduces production costs, and improves overall production benefits. 4. Performance and quality optimization of biaxially oriented film In terms of the production of biaxially stretched films, the present invention has unique advantages. The coordinated control of the tension roller and the contact roller ensures the stability of the tension during the biaxial stretching process. During biaxial stretching, the film is subjected to biaxial stretching forces in the longitudinal and transverse directions. The equipment can ensure uniform tension distribution to avoid uneven stretching or damage to the film surface. The adjustment of the winding roller parameters and the reasonable setting of the formula tension meet the needs of each stage of biaxial stretching, and improve the comprehensive performance of the film after biaxial stretching, such as uniformity of tensile strength, improvement of optical properties and reduction of thickness deviation, etc., thereby improving the overall quality of the biaxially stretched film roll, enhancing the adaptability and stability of the biaxial stretching process, and facilitating large-scale, high-quality biaxially stretched film production. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the winding structure, showing the positional relationship between the tension roller, contact roller, winding rollers A, B and the film, to help understand the winding method: 1- tension roller; 2- contact roller; 31- winding roller position A; 32- winding roller position B; 4- film; Figure 2For contact roller gap winding mode M f The calculation steps of Figure 3 For contact roller contact winding mode M f The calculation steps. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0019] It should be noted that the term "including" in the specification and claims of the present invention and the above-mentioned drawings is intended to cover non-exclusive inclusions. In the present invention, the directions or positional relationships indicated by the terms "upper", "lower", "front", "rear", etc. are based on the directions or positional relationships shown in the drawings. These terms are mainly used to better describe the present invention and its embodiments, and are not used to limit the indicated components to have specific directions. For those of ordinary skill in the art, the specific meanings of these terms in the present invention can be understood according to specific circumstances.

[0020] Example 1 This embodiment provides a film winding machine, which includes a transmission module and a winding module. The transmission module is arranged adjacent to the winding module. The conveying module comprises a tension roller 1 and a contact roller 2, and the conveying module is used to convey the film 4 to the winding module; The winding module comprises a winding roller 31 and a winding roller 32, wherein the winding roller 31 is located at station A, which is close to the contact roller 2, and the winding roller 32 is located at station B, which is far away from the contact roller 2. The winding module is used to continuously wind the film 4; Optionally, in the conveying module, the tension roller 1 is located at the far end of the winding module compared to the contact roller 2, and the contact roller 2 is located at the near end of the winding module compared to the tension roller 1, and the tension roller 1 is used to measure the film tension in real time. When the film is wound, the contact roller 2 is close to the winding roller 31, that is, the gap winding method; Optionally, the gap winding is that the contact roller 2 moves in real time with the change of the thickness of the winding material to maintain the set gap distance. During the entire winding process, the tension roller 1 runs at a constant speed, the contact roller 2 adopts a positioning control mode, and the winding roller 31 adopts speed control + torque limit control.

[0021] Example 2 This embodiment provides a method for winding a film using the film winding machine, using a gap winding method, including the following steps: S1 conveyor film The contact roller 2 is moved to the waiting position, and the film 4 is manually pulled through the tension roller 1 and the contact roller 2 to the winding roller 32 located at the station B, and the winding starts to accelerate to the set speed; S2: Film winding The winding roller 32 winds up a section of waste material and then cuts the film, and winds the film 4 onto the winding roller 31 on the A station. The contact roller 2 adopts the positioning control mode, and the contact roller 2 moves in real time with the change of the thickness of the winding material to maintain the set gap distance. During the whole winding process, the tension roller 1 runs at a constant speed, and the winding roller 31 adopts speed control + torque limit control, and starts to enter the normal winding mode; S3: Change roll When the winding roller 31 on the A station reaches full roll, it switches clockwise to the B station, cuts the film, takes down the full roll of film, and repeats the operation of S1. Thereafter, the above steps are repeated every time the winding length reaches full roll until the winding is completed or the machine stops unexpectedly.

[0022] Optionally, the speed control is controlled by the winding speed, and the torque limit control is controlled by the winding roller motor torque limit control; Optionally, the formula tension setting range of the winding film is 100-1000N, and the given value of the formula tension decreases linearly from small to large according to the real-time winding diameter; Optionally, the winding roller motor limiting torque is jointly affected by the formula tension, the real-time winding diameter of the winding roller, the acceleration and deceleration compensation torque, the winding roller friction torque, and the PID compensation torque; Optionally, the control of the winding roller motor torque limit is divided into a stable winding situation, a winding acceleration and deceleration stage situation, and a switching station winding situation according to different winding situations: ① Under stable winding conditions, set the winding speed v 1= k · v 0, where k is the speed coefficient. In order to make the coiling saturate quickly, generally k The value is 1.05-1.1, v 0 is the production line speed, which is set manually; Winding roller motor limit torque M 1=1 / 2 F · D 1+ M f + M x ,inF Set the tension for the film, manually set, D 1 is the real-time winding diameter of the winding roller, which can be measured by the sensor; M f It is the friction torque of the winding roller, which can be directly read by the frequency converter of the film winding machine. M x It is the PID compensation torque; ② In the winding acceleration and deceleration stage, set the winding speed v 1= k · v 0, k The value is 1.05-1.1; Winding roller motor limit torque M 1=1 / 2 F · D 1+ M ad + M f + M x ,in, M ad Compensation torque for acceleration and deceleration; ③ When switching the winding position, set the winding speed v 1= k ·( v 0- v 2), where v 2 is the compensation speed, k The value is 1.05-1.1; Winding roller motor limit torque M 1=1 / 2 F · D 1+ M f + M x ; This embodiment uses an actual measurement method to obtain M f , specific M f The measurement method is as follows: Contact roller gap winding method M f The calculation steps are as follows: S1, the contact roller moves to the set gap distance; S2, the take-up roller drive is set to torque mode; S3, i =1; S4, n sv = nmax · i / c ,in, n sv The actual running speed of the motor can be read directly from the driver. n max is the rated speed of the motor, i is the number of measurements that have been made, c is the total number of measurements required, c Any value can be taken, generally 10-20 is more appropriate. c =10; S5, motor set torque M sp Start from 0 and increase slowly step by step, measuring the motor in real time n sv , continue to adjust M sp Until the motor speed remains constant, record the n sv and the corresponding M sp ; M sp During operation, it is manually adjusted. n sv = n max · i / c , that is, when the actual running speed of the motor reaches the expected speed and remains constant, M sp = M f , thus recorded i =1, 2, 3, ..., c 10 groups M f The measurement results are saved in the form of a table. In the actual winding process, according to the actual working conditions of the contact roller, the corresponding M f ; S6, i = i +1; S7, if i >10, the measurement is completed, otherwise return to step S4.

[0023] Acceleration and deceleration torque M ad The calculation of is as follows: M ad =2 V diff ·( J 0+J 1) / ( D 1. t ),in, t is the acceleration and deceleration time, V diff is the speed change value, J 0 is the moment of inertia of the take-up system, which can be directly read through the self-tuning function of the take-up drive. J 1 is the moment of inertia of the film, which can be obtained according to the material and roll diameter of the film; PID compensation torque M x The calculation is as follows: M x = k p ( F pv F )+1 / k t ,in, k p It is the tension closed loop ratio, which is set manually during operation. F pv The real-time tension of the winding is measured by the tension roller 1 in real time. F It is the formula tension, which is set manually during operation. k t It is the tension closed loop integration time, which is set manually during operation; v 2 is calculated as follows: v 2= oh ·( L + D 1 / 2) / 2·sin ϴ ,in, oh The rotation speed for the coiling station switching is set manually during operation. L is the distance between the two winding rollers, obtained from the film winding machine's own parameters, ϴ It is the angle of the winding roller, which is read directly by the drive.

[0024] In the case of speed control + torque limit control, record M f It plays many important roles: 1. Accurately control the coiling process The accuracy of torque limit control is one of the key parameters for calculating the limit torque of the winding roller motor. For example, in this embodiment, the accuracy of torque limit control is achieved in different situations such as stable winding, winding acceleration and deceleration, and switching station winding. M f The value can make the motor output appropriate torque (M 1) Ensure that the winding process is carried out according to the predetermined speed and tension requirements to avoid the film being wound too loosely or too tightly due to insufficient or excessive torque, thereby achieving constant tension winding of the film and reducing problems such as film wrinkles, looseness, or even film breakage; 2. Adapt to different working conditions: The working conditions during the winding process are complex and changeable. For example, changes in film material and thickness, adjustment of winding speed, and switching of workstations will affect the stress of the winding roller. M f The records help the system adjust the motor output torque in real time according to the actual working conditions, so that the winder can adapt to various complex working conditions and ensure the stability of the winding quality. For example, when the film thickness changes, the friction of the winding roller will change. M f value, the motor torque can be adjusted in time to ensure stable tension; 3. Improve the versatility and adaptability of equipment: Different film materials and specifications (such as thickness, width, etc.) will produce different friction characteristics during the winding process, resulting in M f The difference in values, record M f The value helps the winder to quickly adjust the motor control parameters when processing various types of films to adapt to different winding requirements and improve the versatility and adaptability of the equipment to different film products; 4. Feedback control optimization: M f The data can be used as feedback signals to optimize the control algorithm of the coiler. By continuously adjusting the control parameters, the performance of the coiler can be continuously improved, more accurate tension control and coiling speed control can be achieved, and production efficiency and product quality can be improved. For example, when using the PID control algorithm, M f The data can be used as one of the input parameters of the PID controller to adjust the PID parameters in real time and improve the control accuracy; 5. Simplified operation process: When setting the coiler parameters, the operator does not need to manually estimate or repeatedly test the friction torque of the coiler roller, but can directly query the recorded M f Parameters can be set by simply pressing the value, which simplifies the operation process, reduces the dependence on operator experience, and improves the usability of the equipment; 6. Rapid adjustment and adaptation: When it is necessary to change the film material or adjust the winding process, the operator can M f The data can be used to quickly adjust the motor control parameters, so that the equipment can quickly adapt to new working requirements, reduce equipment debugging time and improve production efficiency.

[0025] In addition, the existing technology mostly uses open-loop or simple PID tension closed-loop control during winding, which exposes obvious deficiencies in the biaxial stretching process. Biaxial stretching requires precise control of the stretching degree of the film in two directions (longitudinal and transverse), while open-loop control cannot provide real-time feedback on the tension conditions. Simple PID tension closed-loop control is prone to tension oscillations when the system is disturbed. For example, during longitudinal stretching, if the tension is unstable, the film thickness may be uneven; during transverse stretching, tension fluctuations will lead to inconsistent molecular orientation, thereby affecting the optical properties and mechanical properties of the film, such as decreased transparency and uneven tensile strength.

[0026] The present embodiment provides the following improvements and advantages on the biaxial stretching technology in the context of the prior art: 1. Accurate tension control system adapts to bidirectional stretching requirements The tension roller 1 and the contact roller 2 cooperate to ensure the stability of biaxial stretching: In this embodiment, the tension roller runs at a constant speed during the entire winding process, which provides a stable reference for tension measurement during biaxial stretching. During biaxial stretching, the tension roller can accurately sense the tension change under the action of longitudinal and transverse stretching forces on the film. During gap winding, the positioning control mode of the contact roller ensures that a stable gap distance can be maintained when the thickness of the film roll changes, so that the tension is evenly distributed on the film, which is beneficial to the uniformity of biaxial stretching.

[0027] 2. Adjustment of winding roller parameters to meet the requirements of each stage of biaxial stretching: The winding roller adopts speed control + torque limit control mode, which plays a key role in different stages of biaxial stretching. In the stable stretching stage, by reasonably setting the winding speed (and accurately calculating the motor limit torque), it can ensure that when the film reaches a stable state in biaxial stretching, the tension and stretching speed match, thereby improving the film performance; in the stretching acceleration and deceleration stage, the acceleration and deceleration compensation torque M ad The introduction of can effectively deal with the influence of inertial force on film tension caused by changes in biaxial stretching speed. For example, when longitudinal stretching is accelerated, it can prevent sudden changes in transverse tension due to inertia, ensuring a smooth transition of the biaxial stretching process; special speed and torque adjustment when switching station winding ( v 1= k ( v 0- v 2)) It also provides stable conditions for continuous winding during biaxial stretching, avoiding the influence of stretching effect due to station switching; 3. Formula tension adjustment optimizes the quality of biaxially stretched film rolls: The formula tension setting range of the wound film is 100-1000N and is adjusted linearly according to the real-time roll diameter, which is of great significance to the quality of the biaxially stretched film roll. In the early stage of biaxially stretched film winding, a smaller roll diameter corresponds to a larger formula tension, which is conducive to establishing uniform initial stress in the film, providing good starting conditions for biaxial stretching, making it easier for the molecular chains to be stretched in both directions; as the roll diameter increases, the tension decreases linearly, adapting to the changes in the internal stress distribution of the film after biaxial stretching, avoiding additional stress concentration in the film during the winding process due to excessive tension, ensuring the flatness and uniformity of the biaxially stretched film roll during the entire winding process, and reducing wrinkles and sagging caused by the combined effects of stretching and winding; 4. Comprehensive parameters affect motor torque to achieve precise control of bidirectional stretching: The winding roller motor torque limit is affected by multiple parameters. The precise measurement and calculation of these parameters provide precise control means for bidirectional stretching. The synergistic effect of formula tension, real-time winding diameter of winding roller, acceleration and deceleration compensation torque, friction torque of winding roller and PID compensation torque enables the motor to respond to the tension demand of the film in real time during bidirectional stretching. For example, when the transverse stretching ratio is large, the system adjusts the motor torque in time according to the measured parameters to ensure the balance of longitudinal and transverse tension, achieve precise control of bidirectional stretching, and improve the comprehensive performance of the film, such as improving tensile strength and optical properties.

[0028] Example 3 The present invention provides a film winding machine, which comprises a transmission module and a winding module, wherein the transmission module is arranged adjacent to the winding module. The conveying module comprises a tension roller 1 and a contact roller 2, and the conveying module is used to convey the film 4 to the winding module; The winding module comprises a winding roller 31 and a winding roller 32, wherein the winding roller 31 is located at station A, which is close to the contact roller 2, and the winding roller 32 is located at station B, which is far away from the contact roller 2. The winding module is used to continuously wind the film 4; Optionally, in the conveying module, the tension roller 1 is located at the far end of the winding module compared to the contact roller 2, and the contact roller 2 is located at the near end of the winding module compared to the tension roller 1, and the tension roller 1 is used to measure the film tension in real time, and the contact roller 2 is pressed on the winding roller 31 when winding the film, that is, the contact winding method; Optionally, the gap winding is that the contact roller 2 moves in real time with the change of the thickness of the winding material to maintain the set gap distance. During the entire winding process, the tension roller 1 runs at a constant speed, the contact roller 2 adopts a torque control mode, and the winding roller 31 adopts speed control + torque limit control.

[0029] Example 4 This embodiment provides a method for winding a film using the film winding machine, using a contact winding method, including the following steps: S1 conveyor film The contact roller 2 is moved to the waiting position, and the film 4 is manually pulled through the tension roller 1 and the contact roller 2 to the winding roller 32 located at the station B, and the winding starts to accelerate to the set speed; S2: Film winding The winding roller 32 winds up a section of waste material and cuts the film, and then winds the film 4 onto the winding roller 31 on the A station. The contact roller 2 adopts the torque control mode, and the contact roller 2 presses on the winding film 4 according to the formula setting pressure. During the whole winding process, the tension roller 1 runs at a constant speed, and the winding roller 31 adopts speed control + torque limit control, and starts to enter the normal winding mode; S3: Change roll When the winding roller 31 on the A station reaches full roll, it switches clockwise to the B station, cuts the film, takes down the full roll of film, and repeats the operation of S1. Thereafter, the above steps are repeated every time the winding length reaches full roll until the winding is completed or the machine stops unexpectedly.

[0030] This embodiment uses an actual measurement method to obtain M f , specific M f The measurement method is as follows: Contact roller contact winding mode M f The calculation steps are as follows: S1, the take-up roller drive is set to torque mode; S2, j =1, j is the number of contact roller pressure groups that have been measured; S3, F r = F max · j / c 0, c 0 is the number of contact roller pressure groups to be measured, c 0 can take any value, generally 10-20 is more appropriate. c 0=10, F r The contact roller pressure is manually adjusted during operation. F max Set the maximum pressure for the contact roller; S4, the contact roller is pressed onto the take-up roller according to the set pressure; S5, i =1, iThe number of measurements for each contact roller pressure; S6, n sv = n max · i / c ,in, n sv The actual running speed of the motor can be read directly from the driver. n max is the rated speed of the motor, i is the number of measurements that have been made, c The number of measurements of friction torque for each set pressure of the contact roller, c Any value can be taken, but generally 10-20 is more appropriate. c =10; S7, motor set torque M sp Start from 0 and increase slowly step by step, measuring the motor in real time n sv , continue to adjust M sp Until the motor speed remains constant, record the n sv and the corresponding M sp ; M sp Manual adjustment during operation; with gap winding mode M f The calculation steps are the same as n sv = n max · i / c , that is, when the actual running speed of the motor reaches the expected speed and remains constant, M sp = M f , thus recorded i =1, 2, 3, ..., c 10 groups M f The measurement results are saved in the form of a table. In the actual winding process, according to the actual working conditions of the contact roller, the corresponding M f ; S8, i = i +1; S9, if i >10, the measurement is completed, otherwise return to step S6; S10, j = j +1; S11. If j >10, the measurement is completed, otherwise return to step S3.

[0031] During contact winding, the torque control mode with pressure set according to the recipe can accurately adjust the contact roller pressure according to the different materials and stretching requirements of the biaxially oriented film, ensuring that the film is subjected to appropriate tension when stretched in both directions, avoiding uneven stretching or film surface damage caused by improper tension.

[0032] The above description is only a preferred embodiment of the present invention and does not constitute any other form of limitation to the present invention. Any modification or equivalent change made based on the technical essence of the present invention still falls within the scope of protection required by the present invention.

Claims

1. A film winding machine, characterized in that: The film winding machine comprises a conveying module and a winding module, wherein the conveying module is arranged adjacent to the winding module. The conveying module comprises a tension roller (1) and a contact roller (2), and the conveying module is used to convey the film (4) to the winding module; The winding module comprises a winding roller (31) and a winding roller (32), wherein the winding roller (31) is located at station A, which is close to the contact roller (2), and the winding roller (32) is located at station B, which is far away from the contact roller (2). The winding module is used to continuously wind the film (4).

2. A film winder according to claim 1, characterized in that: In the conveying module, the tension roller (1) is located at the far end of the winding module compared to the contact roller (2), and the contact roller (2) is located at the near end of the winding module compared to the tension roller (1). The tension roller (1) is used to measure the film tension in real time. When winding the film, the contact roller (2) is close to the winding roller (31) or pressed on the winding roller (31).

3. A method for winding a film using the film winding machine according to any one of claims 1 or 2, characterized in that: The steps include: S1 conveyor film The contact roller (2) is moved to the waiting position, and the film (4) is manually pulled through the tension roller (1) and the contact roller (2) to the winding roller (32) located at the work station B, and the winding begins to accelerate to the set speed; S2: Film winding The winding roller (32) winds up a section of waste material and then cuts the film, and then winds up the film (4) onto the winding roller (31) on the A station, and starts to enter the normal winding mode; S3: Change roll When the winding roller (31) on the A station reaches full roll, it switches to the B station clockwise, cuts the film, takes down the full roll of film, and repeats the operation of S1. Thereafter, this step is repeated every time the winding length reaches full roll until the winding is completed or the machine stops unexpectedly.

4. The film curling method according to claim 3, characterized in that: The film winding method is divided into two types: gap winding and contact winding.

5. The film curling method according to claim 3, characterized in that: The gap winding is that the contact roller (2) moves in real time with the change of the thickness of the winding material to maintain the set gap distance. During the entire winding process, the tension roller (1) runs at a constant speed, the contact roller (2) adopts a positioning control mode, and the winding roller (31) adopts speed control + torque limit control.

6. The film curling method according to claim 4, characterized in that: The contact winding is that the contact roller (2) is pressed on the winding film (4) according to the pressure set by the formula, the tension roller (1) runs at a constant speed during the entire winding process, the contact roller (2) adopts a torque control mode, and the winding roller (31) adopts a speed control + torque limit control mode.

7. The film rolling method according to any one of claims 5 or 6, characterized in that: The speed control is controlled by the winding speed, and the torque limit control is controlled by the winding roller motor torque limit control.

8. The film curling method according to claim 3, characterized in that: The setting range of the formula tension of the winding film is 100-1000N, and the given value of the formula tension decreases linearly from small to large according to the real-time winding diameter.

9. The film curling method according to claim 8, characterized in that: The winding roller motor limiting torque is jointly affected by the formula tension, the real-time winding diameter of the winding roller, the acceleration and deceleration compensation torque, the winding roller friction torque, and the PID compensation torque.

10. The film curling method according to claim 3, characterized in that: The control of the torque limiting of the winding roller motor is divided into a stable winding situation, a winding acceleration and deceleration stage situation, and a switching station winding situation according to different winding situations.

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