Hot melt glue rewinding device and process

Abstract

The present application relates to the technical field of glass fiber composite, in particular to a hot melt adhesive rewinding equipment and process. It comprises a rack, a yarn feeding unit, an adhesive film unwinding unit, an electromagnetic heating traction roller group, a winding unit, a glue scraping mechanism, a sensor group and a PLC general control system. The present application has high automation degree, is suitable for continuous production, has uniform heating during low-speed compounding in the production process, high compounding quality, high precision of adhesive film unwinding tension control, stable compounding quality, partition tension control, which can effectively avoid glass fiber breakage, effectively eliminate static electricity, improve infiltration effect, and realize active and accurate control of adhesive layer thickness, integrated integration of whole-process tension collaborative management and glue solution recycling, upgrade the traditional open-loop production mode relying on manual experience to the data-driven intelligent closed-loop production mode, realize systematic leap in five dimensions of adhesive layer thickness control precision, width direction consistency, product quality stability, raw material utilization rate and automation degree.

Description

Technical Field

[0001] This invention relates to the field of glass fiber composite technology, and in particular to a hot melt adhesive bonding equipment and process. Background Technology

[0002] Hot melt adhesive bonding technology involves heating and melting a hot melt adhesive film with a yarn substrate to form a composite yarn material with adhesive properties. It is widely used in fields such as tape substrate reinforcement, electrical materials, and industrial fabrics.

[0003] The existing fiberglass reeling process mainly faces the following technical problems: Firstly, tension control is difficult.

[0004] Fiberglass yarn has a high modulus, high brittleness, and low elongation at break, making it extremely sensitive to tension fluctuations. The lack of an independent tension control mechanism between the unwinding and winding sides can easily lead to fiber breakage and increased fuzzing due to excessive tension during the lamination process, or relaxation and wrinkling due to insufficient tension. This severely affects the uniformity of the lamination and the performance of the product, and consequently, the tensile strength and electrical insulation properties of the tape.

[0005] Secondly, the precision of the film unwinding tension control is insufficient.

[0006] Traditional methods of unwinding adhesive films often use magnetic powder brakes or mechanical friction to control tension, which suffers from problems such as slow response, large tension fluctuations, and low control accuracy. During the unwinding process, the tension of hot melt adhesive films is unstable, easily leading to stretching deformation, wrinkles, or misalignment, affecting the alignment accuracy with the fiberglass yarn and the uniformity of the composite.

[0007] Third, the heating uniformity is insufficient during low-speed compounding.

[0008] In the production of glass fiber reinforced composite yarns, due to the limitations of the adhesive film's melt wetting time and the poor thermal conductivity of glass fiber yarns, a low-speed composite process (2~50m / min) is often required to ensure composite quality. However, under low-speed operation, traditional resistance heating methods result in uneven heat radiation and large fluctuations in roller surface temperature distribution. This can easily lead to insufficient wetting of the adhesive film on the glass fiber surface or localized overheating, causing the adhesive film to age and reducing the peel strength and durability of the tape composite layer. In electrical material applications, this may lead to the risk of insulation layer detachment.

[0009] Fourth, the quality of the rolls is difficult to guarantee.

[0010] If tension reduction is not controlled as the roll diameter increases during the winding process, defects such as tight inner and loose outer sections and uneven end faces are likely to occur, affecting the appearance and performance of the finished product. In particular, it can easily generate waste products in the subsequent slitting process of the tape, increasing production costs.

[0011] Fifth, the problem of static electricity in fiberglass yarn.

[0012] Fiberglass yarn is prone to static electricity during unwinding and travel, which causes the yarn to attract dust and become frizzy, affecting the wetting and bonding effect between the adhesive film and the fiberglass surface, and thus reducing the interfacial bonding strength of the tape composite layer.

[0013] Sixth, the uniformity of the adhesive layer thickness after lamination lacks active control.

[0014] Existing production lines lack proactive detection and control methods for the uniformity of adhesive layer thickness after laminating hot melt adhesive film and fiberglass yarn. When the adhesive film thickness fluctuates or the lamination pressure is unevenly distributed along the width direction, localized excessive adhesive layer thickness or adhesive buildup can easily occur on the surface of the composite. This not only affects the product appearance but may also lead to problems such as roller sticking and uneven thickness in subsequent yarn processing. Traditional methods rely on manual sampling and adjustment, which are slow to respond and difficult to guarantee batch-to-batch consistency. Summary of the Invention

[0015] The technical problem to be solved by the present invention is to provide a hot melt adhesive re-yarn equipment and process, which achieves high-quality re-yarn production of glass fiber yarn and hot melt adhesive film through the coordinated cooperation of independent tension control in zones, precise adjustment of film unwinding tension driven by servo motor, precise temperature control of electromagnetic heating traction roller, static elimination, tapered tension winding, and online thickness measurement feedback scraping.

[0016] To solve the above-mentioned technical problems, the technical solution of the present invention is: a hot melt adhesive re-yarn process, the innovation of which is: including a frame; A yarn feeding unit is located on one side of the frame and includes a yarn feeding frame on which a plurality of fiberglass yarn spools are provided; The film unwinding unit is mounted on the frame and includes a film unwinding shaft, a servo motor, a hot melt adhesive film roll, and a web guiding device. The servo motor is connected to the film unwinding shaft. An electromagnetic heating traction roller assembly is used to thermally bond hot melt adhesive film and glass fiber yarn, and a cooling roller is also provided on the frame near the discharge side of the electromagnetic heating traction roller assembly. A winding unit is located on the other side of the frame. It includes a winding mechanism. The glass fiber reinforced composite yarn formed after thermal bonding is guided to the winding mechanism by multiple guide rollers to achieve winding. A scraping mechanism is provided between the electromagnetic heating traction roller group and the cooling roller, and is used to scrape off molten adhesive that is too thick in some areas. The sensor group includes a web guiding sensor, a tension sensor, a temperature sensor, and a line laser measuring instrument. The web guiding sensor is mounted on the frame and located on both sides of the width of the hot melt adhesive film. The tension sensor is set on the unwinding path of the adhesive film to detect the tension of the adhesive film. Multiple temperature sensors are installed between the two traction rollers and distributed along the length of the traction rollers. The PLC-based overall control system connects the yarn feeding unit, film unwinding unit, electromagnetic heating traction roller group, winding unit, and sensor group to the PLC-based overall control system, enabling coordinated control of the entire process.

[0017] Furthermore, the electromagnetic heating traction roller group is located on the frame near the composite station of the yarn feeding unit, including at least one set of electromagnetic heating traction rollers, one of which has a built-in electromagnetic induction heating coil for thermally composited hot melt adhesive film and glass fiber yarn, and is connected to a PID temperature control system; the hot melt adhesive film is conveyed to the electromagnetic heating traction roller group via a conveyor roller, and the glass fiber yarn is positioned and aligned by a carding frame before being fed between the two electromagnetic heating traction rollers, while the glass fiber yarn is on the surface of the hot melt adhesive film; In the sensor group, the servo motor is connected to a servo driver, and the servo driver is connected to a tension sensor. The tension sensor is set on the conveyor roller on the film unwinding path to detect the film tension and feed it back to the servo driver. The servo driver controls the servo motor to output torque, forming a closed-loop tension control system.

[0018] Furthermore, a flattening roller is also provided on the frame near the feed side of the electromagnetic heating traction roller group; Each fiberglass yarn bobbin is equipped with an independent magnetic powder brake as a tension controller. An electrostatic elimination device is also provided between the yarn feeding frame and the carding frame; The winding unit also includes a tapered tension control system, a floating roller, and an automatic correction system. The automatic correction system is located on the feed side of the winding shaft to ensure that the winding end face is neat. The floating roller is mounted on the winding unit and acts as a tension buffer to absorb tension fluctuations.

[0019] Furthermore, the adhesive scraping mechanism includes an adhesive scraper and a gap adjustment mechanism, wherein the adhesive scraper is arranged across the width direction of the adhesive film; The scraper is divided into 3 to 10 scraper supports along the width of the adhesive film. The bottom side of each scraper support is the scraping side, and the scraping side is arc-shaped. Each scraper support is provided with an independent gap adjustment mechanism, and the gap between each scraper support and the adhesive film is independently adjustable.

[0020] Furthermore, the scraping support plate includes a scraping section, a connecting block, and a limiting frame, and the gap adjustment mechanism is a lifting servo cylinder; The lifting servo cylinder is mounted on a crossbeam of the frame. A limit frame and a scraping section are provided below the crossbeam. The piston rod of the lifting servo cylinder passes vertically downward through the crossbeam and is fixedly connected to the limit frame. The limit frame is a rectangular frame with a limit block inside. A limit post is also provided at the bottom center of the limit block. The bottom of the limit post passes through the limit frame and is connected to the scraping section. A compression spring is also sleeved inside the limit frame on the periphery of the limit post. A line laser measuring instrument is provided on the side of each scraping section near the electromagnetic heating traction roller group to detect the thickness of the composite material passing through the scraping section area, and the target thickness of the composite material is b.

[0021] Furthermore, the scraping section is also provided with a main recycling channel, a branch recycling channel, and a collection trough that are connected vertically in sequence on the side near the electromagnetic heating traction roller group; The main recycling channel extends along the width of the adhesive film, has a recycling outlet, and a recycling pipe is installed at the recycling outlet. The collection troughs are multiple and evenly distributed in the lower middle position of the scraping section. The top of each collection trough is connected to the main recycling channel through a recycling branch channel. The bottom of the collection trough extends to the lowest point of the scraping section, and its top extends to the middle of the scraping section. The bottom area of ​​the collection trough is larger than its top area. The bottom of the collection trough has an arc-shaped transition, and its depth gradually decreases from bottom to top. The two side walls of the collection trough are designed in a figure-eight shape. Each of the scraping sections is also equipped with a heating element, which heats the adhesive on the scraping side, as well as in the collection tank, the main recycling channel, and the branch recycling channel, to ensure that the scraped adhesive can be collected smoothly. The temperature of the scraping section is independently controlled and is 5 to 30°C higher than the melting point of the hot melt adhesive film.

[0022] Furthermore, a flexible contact layer is provided on the scraping side. The flexible contact layer is made of polytetrafluoroethylene, polyurethane rubber, or silicone rubber, and has a thickness of 1 to 5 mm.

[0023] A re-yarn process for a hot melt adhesive re-yarn equipment, including: Step 1: Unwinding and tension control of fiberglass yarn; The fiberglass yarn bobbin is installed on the unwinding frame; after being positioned by the carding frame, the fiberglass yarn passes through the flattening roller to eliminate wrinkles and enters the composite station; during the unwinding process, the static electricity generated by the fiberglass yarn is eliminated by the static elimination device. Step 2: Film unwinding and servo tension adjustment; The hot melt adhesive film roll is installed on the film unwinding shaft, and the film unwinding tension is adjusted by a servo motor. The closed-loop tension control system detects the film unwinding tension in real time and dynamically adjusts the output torque of the servo motor to keep the film unwinding tension constant. The edge position of the film is detected by the correction device, and the lateral position of the film is adjusted by the correction actuator to align it with the edge of the fiberglass yarn. Step 3: Low-speed thermal bonding using electromagnetically heated traction rollers; The aligned fiberglass yarn and the adhesive film are fed together into the electromagnetic heating traction roller group for thermal bonding; the rotation speed of the electromagnetic heating traction roller is 2~50m / min; the roller surface temperature of the electromagnetic heating traction roller is maintained at 85~115℃ by a PID closed-loop temperature control system; the fiberglass yarn and the adhesive film are fully melted and impregnated on the surface of the electromagnetic heating traction roller; Step 4: Winding and tension control; The composite glass fiber reinforced yarn is guided into the winding mechanism. The winding end adopts a tapered tension control method, and the winding tension gradually decreases as the roll diameter increases. The tapered coefficient is 0.3~0.7. Furthermore, independent operation and control of each HMI is adopted; Independent HMI (Human-Machine Interface) controls key process parameters such as tension, temperature, and speed on the yarn unwinding, film unwinding, and winding sides, replacing the existing method of centralized control of all parameters by a single HMI. Each HMI is connected to the main control system, allowing operators to set, monitor, and adjust process parameters on each side. This enables on-site operation at each workstation without having to travel between the central control panel and the actuators, achieving independent operation and control in each zone.

[0024] Furthermore, between steps three and four, the following steps are also included: S1. After the glass fiber yarn and the adhesive film have been fully melted and impregnated, the composite moves toward the adhesive scraping mechanism. S2. Detect the thickness of the composite material located in each scraping support area that is about to reach the scraping mechanism. When the thickness of the composite material in one or more scraping support areas deviates from the set value b by more than ±0.1mm, start the lifting servo cylinder in the corresponding scraping support area and adjust it to stop when the distance between the scraping plate and the upper surface of the composite material is b±0.05mm. S3. Then, the scraper side is used to scrape the uneven molten adhesive in the area of ​​the scraper support plate, so that the adhesive is evenly distributed on the surface of the glass fiber yarn and in the fiber gaps. At this time, the scraped adhesive is collected through the collection tank, and the adhesive collected in the collection tank is recycled through the recycling support channel, the recycling main channel and the recycling pipe by the vacuum pump. After the uneven molten adhesive in this area is scraped flat, the scraper plate is reset. S4. After the molten adhesive is leveled, the composite is run in a steady flow section with a length of 400-500 mm, and then the composite is cooled and shaped using a cooling roller to obtain a glass fiber yarn mesh reinforced hot melt adhesive composite material with uniform adhesive layer thickness.

[0025] The advantages of this invention are: 1. This invention features a high degree of automation, making it suitable for continuous production. During low-speed lamination in the production process, heating is uniform, resulting in high lamination quality. The film unwinding tension control is highly precise, ensuring stable lamination quality. Zoned tension control effectively prevents fiber breakage and eliminates static electricity, improving wetting effects. It also integrates proactive and precise control of adhesive layer thickness, full-process tension collaborative management, and adhesive recycling, upgrading the traditional open-loop production model reliant on manual experience to a data-driven intelligent closed-loop production model. This represents a systematic leap forward in five dimensions: adhesive layer thickness control precision, width consistency, product quality stability, raw material utilization, and automation level.

[0026] 2. Addressing the need for low-speed lamination processes in glass fiber reinforced composite yarn production, an electromagnetic induction heating method combined with PID closed-loop temperature control is employed, resulting in fast response and high temperature control accuracy. The electromagnetic induction heating coil structure effectively compensates for uneven heat radiation under low-speed operation, ensuring uniform temperature distribution on the roller surface. This allows the adhesive film to fully melt and evenly wet the surface of the glass fiber yarn, resulting in high composite strength. This effectively improves the peel strength and durability of the glass fiber reinforced tape composite layer, meeting the long-term reliability requirements of the electrical materials field for insulation layers.

[0027] 3. A closed-loop tension control system is formed by using a servo motor, a tension sensor, and a servo driver. Compared with the traditional magnetic powder brake, the tension control is more accurate and the response speed is faster. It effectively eliminates tension fluctuations during the unwinding process of the film, avoids film stretching deformation, wrinkles, or offset, and ensures precise alignment and uniform lamination between the film and the fiberglass yarn.

[0028] 4. The tension is independently controlled by a magnetic powder brake on the yarn feeding side, the tension is controlled by a servo motor in a closed loop on the film side, and the tension is controlled by a tapered tension control on the winding side. This achieves independent and precise matching of tension in each area of ​​the entire process, effectively avoiding problems such as fiberglass yarn breakage and increased fuzz, and ensuring the dimensional stability and mechanical property consistency of the fiberglass reinforced composite yarn products. The resulting fiberglass reinforced tape has excellent tensile strength and electrical insulation properties.

[0029] 5. By setting up an electrostatic elimination device, the static electricity generated during the unwinding process of the glass fiber yarn is effectively removed, avoiding dust adsorption and fuzz scattering, ensuring good wetting and bonding between the adhesive film and the surface of the glass fiber yarn, and improving the interfacial bonding strength of the composite yarn.

[0030] 6. The PLC central control system enables coordinated control of the entire process, and the parameters of each unit can be monitored and adjusted in real time, resulting in high production efficiency and making it suitable for the industrial mass production of glass fiber reinforced tape composite materials.

[0031] 7. The tapered tension control, combined with the floating roller buffer device, effectively solves the problem of tension changes caused by the increase of the roll diameter during the winding process, ensuring the neatness of the end face and the uniformity of internal stress of the glass fiber reinforced composite yarn roll, which facilitates subsequent tape coating and slitting processing and effectively reduces the scrap rate.

[0032] 8. This invention integrates a main recycling channel, a secondary recycling channel, and a collection tank inside the scraping section, and uses heating elements to prevent solidification and vacuum pump negative pressure diversion. This enables real-time full recovery of molten adhesive without interfering with the production line channel. At the same time, the multi-point parallel collection tank and anti-clogging design ensure the long-term stable operation of the recycling system. Attached Figure Description

[0033] Figure 1 This is the front view of the present invention.

[0034] Figure 2 This is a partial structural schematic diagram of the present invention.

[0035] Figure 3 For the present invention Figure 2 A partial structural diagram. Detailed Implementation

[0036] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0037] like Figure 1 The hot melt adhesive rewinding equipment shown includes a frame 1, a yarn feeding unit 2, an adhesive film unwinding unit 3, an electromagnetic heating traction roller group 4, a winding unit 5, an adhesive scraping mechanism 7, a sensor group, and a PLC overall control system.

[0038] The yarn feeding unit 2 is located on one side of the frame 1 and includes a yarn feeding frame with several fiberglass yarn spools on it.

[0039] The film unwinding unit 3 is mounted on the frame 1, and is equipped with a film unwinding shaft, a servo motor, a hot melt adhesive film roll and a web guiding device. The servo motor is connected to the film unwinding shaft.

[0040] The electromagnetic heating traction roller group 4 is located on the frame 1 near the lamination station of the yarn feeding unit 2. It includes at least one set of electromagnetic heating traction rollers, one of which has a built-in electromagnetic induction heating coil for thermal lamination of the hot melt adhesive film and the fiberglass yarn. It is also connected to a PID temperature control system, and the surface temperature of the electromagnetic heating traction roller is 85~115℃. The hot melt adhesive film is conveyed into the electromagnetic heating traction roller group 4 via a conveyor roller. The fiberglass yarn is positioned and aligned by a carding frame before being fed between the two electromagnetic heating traction rollers. The fiberglass yarn is on the surface of the hot melt adhesive film. A cooling roller 6 is also provided on the discharge side of the frame 1 near the electromagnetic heating traction roller group 4.

[0041] The winding unit 5 is located on the other side of the frame 1. It includes a winding mechanism. The glass fiber reinforced composite yarn formed after thermal bonding is guided to the winding mechanism by multiple guide rollers to achieve winding.

[0042] The glue scraping mechanism 7 is located between the electromagnetic heating traction roller group 4 and the cooling roller 6, and is used to scrape off the molten glue that is too thick in some areas.

[0043] The sensor group includes a web guiding sensor, a tension sensor, a temperature sensor, and a line laser measuring instrument. The web guiding sensor is mounted on frame 1 and positioned on both sides of the width of the hot melt adhesive film. A servo motor is connected to a servo driver, which in turn is connected to a tension sensor. The tension sensor is located on the unwinding path of the adhesive film, specifically mounted on the conveyor roller, and is used to detect the tension of the adhesive film and feed it back to the servo driver. The servo driver controls the output torque of the servo motor, forming a closed-loop tension control system. Compared with the traditional magnetic powder brake method, the tension control accuracy is higher (±0.5N) and the response speed is faster (≤50ms). It can detect and dynamically adjust in real time, eliminate tension fluctuations, and avoid film stretching deformation, wrinkles, or offset, ensuring precise alignment and uniform bonding between the adhesive film and the fiberglass yarn. Multiple temperature sensors are also installed between the two traction rollers of the electromagnetic heating traction roller group, distributed along the length of the traction roller, to accurately measure the temperature at each location.

[0044] The PLC main control system, the yarn feeding unit 2, the film unwinding unit 3, the electromagnetic heating traction roller group 4, the winding unit 5 and the sensor group are all connected to the PLC main control system to realize the coordinated control of the whole process.

[0045] The PLC overall control system enables coordinated control of the entire process, and the parameters of each unit can be monitored and adjusted in real time, resulting in high production efficiency and making it suitable for the industrial mass production of glass fiber reinforced tape composite materials.

[0046] This invention sets up independent HMIs at each workstation to achieve independent operation and control of each zone. Operators can make adjustments on-site nearby without having to travel back and forth between the control panel and the actuator, effectively improving adjustment response speed and production efficiency.

[0047] A flattening roller 8 is also provided on the feed side of the frame 1 near the electromagnetic heating traction roller group 4.

[0048] Each fiberglass yarn bobbin on the yarn feeding frame is equipped with an independent magnetic powder brake as a tension controller. The tension is independently controlled by a magnetic powder brake on the feeding side, a closed-loop servo motor controls the tension on the film side, and a tapered tension control is used on the winding side. This achieves independent and precise tension matching in each area throughout the entire process, effectively avoiding problems such as fiberglass yarn breakage and increased fuzz, ensuring the dimensional stability and consistent mechanical properties of the fiberglass reinforced composite yarn products. The resulting fiberglass reinforced tape exhibits excellent tensile strength and electrical insulation properties.

[0049] An electrostatic elimination device is installed between the unwinding frame and the carding frame. By setting up the electrostatic elimination device, the static electricity generated by the glass fiber yarn during the unwinding process is effectively removed, which avoids dust adsorption and fuzz scattering, ensures good wetting and bonding between the film and the surface of the glass fiber yarn, and improves the interfacial bonding strength of the composite yarn.

[0050] The winding unit 5 also includes a tapered tension control system, a floating roller, and an automatic correction system. The automatic correction system is located on the feed side of the winding shaft to ensure that the winding end face is neat.

[0051] The floating roller is installed on the winding unit 5 and acts as a tension buffer to absorb tension fluctuations.

[0052] The adhesive scraping mechanism 7 includes an adhesive scraper and a gap adjustment mechanism, with the adhesive scraper arranged across the width of the adhesive film.

[0053] The squeegee is divided into 3 to 10 squeegee supports along the width of the adhesive film. The bottom side of each squeegee support is the squeegee side, and the squeegee side is arc-shaped. Each squeegee support is equipped with an independent gap adjustment mechanism, and the gap between each squeegee support and the adhesive film is independently adjustable.

[0054] Fluctuations in adhesive layer thickness along the width direction typically occur in the middle and at the two side edges, therefore at least three segments are required for segmented control. When there are more than ten segments, the detection spot size of the line laser measuring instrument becomes limited due to the narrow width of each segment, and an excessive number of segments increases control complexity and cost.

[0055] Specifically, such as Figure 2 , 3 The scraper plate shown includes a scraper section 71, a connecting block, and a limiting frame 73. Each scraper section 71 corresponds to a gap adjustment mechanism, which is a lifting servo cylinder 72.

[0056] The lifting servo cylinder 72 is mounted on a crossbeam 11 of the frame 1. A limit frame 73 and a scraping section 71 are set below the crossbeam 11. The piston rod of the lifting servo cylinder 72 passes vertically downward through the crossbeam and is fixedly connected to the limit frame 73. The limit frame 73 is a rectangular frame with a limit block 74 inside. A limit post 75 is also provided at the bottom center of the limit block 74. The bottom of the limit post 75 passes through the limit frame 73 and is connected to the scraping section 71. A compression spring is also sleeved inside the limit frame 73 on the periphery of the limit post 75.

[0057] A line laser measuring instrument is provided on one side of each scraping section 71 near the electromagnetic heating traction roller group 4 to detect the thickness of the composite material passing through the area of ​​the scraping section 71, and the target thickness of the composite material is b.

[0058] Specifically, on the side of the scraping section 71 near the electromagnetic heating traction roller group 4, there is also a recycling main channel 76, a recycling branch channel 77, and a collection trough 78 that are connected vertically in sequence.

[0059] The main recycling channel 76 extends along the width of the adhesive film and has a recycling outlet, at which a recycling pipe is installed.

[0060] There are multiple collection troughs 78, which are evenly distributed in the lower middle position of the scraping section 71. The top of each collection trough 78 is connected to the main recycling channel 76 through a recycling branch channel 77.

[0061] The bottom of the collection trough 78 extends to the lowest point of the scraping section 71, and its top extends to the middle of the scraping section 71. The bottom area of ​​the collection trough 78 is larger than its top area. The bottom 781 of the collection trough 78 has an arc transition, and its depth gradually decreases from bottom to top. The two side walls 782 of the collection trough 78 have an eight-shaped design.

[0062] Each scraping section 71 is also equipped with a heating element. The heating element heats the glue on the scraping side, as well as the glue in the collection tank 78, the main recycling channel 76, and the recycling branch channel 77, to ensure that the scraped glue can be collected smoothly. The temperature of the scraping section 71 is independently controlled and is 5 to 30°C higher than the melting point of the hot melt adhesive film, which can completely prevent the hot melt adhesive from cooling and solidifying and clogging the pipes.

[0063] The bottom of the collection tank has an arc-shaped transition, the bottom area is larger than the top area, and the depth gradually decreases from bottom to top. This allows the adhesive to flow smoothly from the large bottom area into the narrower branch channel inlet, preventing the adhesive from accumulating and clogging at the inlet.

[0064] Multiple evenly distributed collection tanks are connected in parallel to the main recycling channel through their respective recycling branch channels, ensuring that the adhesive scraped off from any scraping section has an independent suction path and that the entire width of recycling is not affected by a blockage in one place.

[0065] A flexible contact layer is also covered on the scraping side. The flexible contact layer is made of polytetrafluoroethylene, polyurethane rubber or silicone rubber, with a thickness of 1 to 5 mm, and the flexible contact layer is also set to fit the collection tank 81.

[0066] A re-yarn process for a hot melt adhesive re-yarn equipment, including: Step 1: Unwinding and tension control of fiberglass yarn: The fiberglass yarn bobbin is installed on the unwinding frame. After being positioned by the carding frame, the fiberglass yarn passes through the flattening roller 8 to eliminate wrinkles before entering the laminating station. During the unwinding process, an electrostatic eliminator is used to eliminate static electricity generated in the fiberglass yarn.

[0067] Step 2: Film unwinding and servo tension adjustment: The hot melt adhesive film roll is mounted on the film unwinding shaft, and the film unwinding tension is regulated by a servo motor. A closed-loop tension control system monitors the film unwinding tension in real time and dynamically adjusts the servo motor output torque to maintain a constant unwinding tension. The film's edge position is detected by a web-aligning device, and the web-aligning actuator adjusts the film's lateral position to align it with the edge of the fiberglass yarn.

[0068] Step 3: Low-speed thermal bonding of electromagnetically heated traction rollers: The aligned fiberglass yarn and adhesive film are fed together into the electromagnetic heating traction roller group 4 for thermal bonding. The rotation speed of the electromagnetic heating traction roller is 2~50m / min. The roller surface temperature of the electromagnetic heating traction roller is maintained at 85~115℃ by a PID closed-loop temperature control system. The fiberglass yarn and adhesive film are fully melted and impregnated on the surface of the electromagnetic heating traction roller for bonding.

[0069] Step 4: Winding and Tension Control The composite glass fiber reinforced yarn is guided into the winding mechanism. The winding end adopts a tapered tension control method, and the winding tension gradually decreases as the roll diameter increases. The tapered coefficient is 0.3~0.7.

[0070] The tapered tension control, combined with the floating roller buffer device, effectively solves the problem of tension changes caused by the increase in roll diameter during the winding process. This ensures the neatness of the end face and the uniformity of internal stress of the glass fiber reinforced composite yarn roll, which facilitates subsequent tape coating and slitting processes and effectively reduces the scrap rate.

[0071] Throughout the production process, each HMI is operated and controlled independently: Independent HMI (Human-Machine Interface) controls key process parameters such as tension, temperature, and speed on the yarn unwinding, film unwinding, and winding sides, replacing the existing method of centralized control of all parameters by a single HMI. Each HMI is communicatively connected to the main control system, allowing operators to set, monitor, and adjust process parameters on each side via their respective HMIs. This enables localized operation at each workstation, eliminating the need to travel between the central control panel and individual actuators, thus achieving independent operation and control for each zone.

[0072] Between step three and step four, the following steps are also included: S1. After the glass fiber yarn and the adhesive film have been fully melted and impregnated, the composite moves toward the adhesive scraping mechanism 7.

[0073] S2. Detect the thickness of the composite material located in each scraping support area that is about to reach the scraping mechanism 7. When the thickness of the composite material in one or more scraping support areas deviates from the set value b by more than ±0.1mm, start the lifting servo cylinder 72 corresponding to the scraping support area and adjust it to stop when the distance between the scraping plate and the upper surface of the composite material is b±0.05mm.

[0074] S3. Then, the scraper side is used to scrape the uneven molten adhesive in the area of ​​the scraper support plate to make the adhesive evenly distributed on the surface of the glass fiber yarn and in the gaps between the fibers. At this time, the scraped adhesive is collected through the collection tank 78, and the adhesive collected in the collection tank 78 is recycled through the recycling support channel 77, the recycling main channel 76 and the recycling pipe by the vacuum pump. After the uneven molten adhesive in this area is scraped flat, the scraper plate is reset.

[0075] It achieves segmented adaptation of composite thickness and targeted scraping of adhesive, thus enabling precise repair of local defects without interfering with areas of normal thickness.

[0076] The actual thickness of the composite material in each scraper support area deviates from the target thickness to varying degrees.

[0077] The value of segmented adhesive application lies in allowing each segment to independently find the same target value based on its own degree of deviation, and making differentiated compensation for the type and degree of deviation in different areas, rather than having all segments accept the same fixed gap that cannot meet the needs of all areas.

[0078] S4. After the molten adhesive is leveled, the composite is run in a steady flow section with a length of 400-500 mm, and then the composite is cooled and shaped using cooling roller 6 to obtain a glass fiber yarn mesh reinforced hot melt adhesive composite material with uniform adhesive layer thickness.

[0079] This invention features a high degree of automation, making it suitable for continuous production. It ensures uniform heating and high-quality lamination during low-speed lamination. The film unwinding tension control is highly precise, resulting in stable lamination quality. Zoned tension control effectively prevents fiber breakage, eliminates static electricity, and improves wetting. It also achieves proactive and precise control of adhesive layer thickness, integrated tension management throughout the entire process, and integrated adhesive recycling. This upgrades the traditional open-loop production model, which relies on manual experience, to a data-driven intelligent closed-loop production model, achieving a systematic leap forward in five dimensions: adhesive layer thickness control precision, width consistency, product quality stability, raw material utilization, and automation level.

[0080] This invention addresses the low-speed lamination process required in the production of glass fiber reinforced composite yarns by employing electromagnetic induction heating combined with PID closed-loop temperature control, resulting in fast response and high temperature control accuracy. The electromagnetic induction heating coil structure effectively compensates for uneven heat radiation under low-speed operation, ensuring a uniform temperature distribution on the roller surface. This allows the adhesive film to fully melt and evenly wet the surface of the glass fiber yarn, resulting in high composite strength. This effectively improves the peel strength and durability of the glass fiber reinforced tape composite layer, meeting the long-term reliability requirements of the electrical materials field for insulation layers.

[0081] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A hot melt adhesive re-yarn equipment, characterized in that: Including racks; A yarn feeding unit is located on one side of the frame and includes a yarn feeding frame on which a plurality of fiberglass yarn spools are provided; The film unwinding unit is mounted on the frame and includes a film unwinding shaft, a servo motor, a hot melt adhesive film roll, and a web guiding device. The servo motor is connected to the film unwinding shaft. An electromagnetic heating traction roller assembly is used to thermally bond hot melt adhesive film and glass fiber yarn, and a cooling roller is also provided on the frame near the discharge side of the electromagnetic heating traction roller assembly. A winding unit is located on the other side of the frame. It includes a winding mechanism. The glass fiber reinforced composite yarn formed after thermal bonding is guided to the winding mechanism by multiple guide rollers to achieve winding. A scraping mechanism is provided between the electromagnetic heating traction roller group and the cooling roller, and is used to scrape off molten adhesive that is too thick in some areas. The sensor group includes a web guiding sensor, a tension sensor, a temperature sensor, and a line laser measuring instrument. The web guiding sensor is mounted on the frame and located on both sides of the width of the hot melt adhesive film. The tension sensor is set on the unwinding path of the adhesive film to detect the tension of the adhesive film. Multiple temperature sensors are installed between the two traction rollers and distributed along the length of the traction rollers. The PLC-based overall control system connects the yarn feeding unit, film unwinding unit, electromagnetic heating traction roller group, winding unit, and sensor group to the PLC-based overall control system, enabling coordinated control of the entire process.

2. The hot melt adhesive re-yarn equipment according to claim 1, characterized in that: The electromagnetic heating traction roller group is located on the frame near the composite station of the yarn feeding unit, and includes at least one set of electromagnetic heating traction rollers. One of the electromagnetic heating traction rollers has an electromagnetic induction heating coil built in it for thermally bonding the hot melt adhesive film and the glass fiber yarn, and is connected to a PID temperature control system. The hot melt adhesive film is conveyed to the electromagnetic heating traction roller group via a conveyor roller, and the glass fiber yarn is positioned and aligned by a carding frame before being fed between the two electromagnetic heating traction rollers, while the glass fiber yarn is on the surface of the hot melt adhesive film. In the sensor group, the servo motor is connected to a servo driver, and the servo driver is connected to a tension sensor. The tension sensor is set on the conveyor roller on the film unwinding path to detect the film tension and feed it back to the servo driver. The servo driver controls the servo motor to output torque, forming a closed-loop tension control system.

3. The hot melt adhesive re-yarn equipment according to claim 2, characterized in that: A flattening roller is also provided on the frame near the feed side of the electromagnetic heating traction roller group; Each fiberglass yarn bobbin is equipped with an independent magnetic powder brake as a tension controller. An electrostatic elimination device is also provided between the yarn feeding frame and the carding frame; The winding unit also includes a tapered tension control system, a floating roller, and an automatic correction system. The automatic correction system is located on the feed side of the winding shaft to ensure that the winding end face is neat. The floating roller is mounted on the winding unit and acts as a tension buffer to absorb tension fluctuations.

4. The hot melt adhesive re-yarn equipment according to claim 1, characterized in that: The adhesive scraping mechanism includes an adhesive scraper and a gap adjustment mechanism, wherein the adhesive scraper is arranged across the width of the adhesive film. The scraper is divided into 3 to 10 scraper supports along the width of the adhesive film. The bottom side of each scraper support is the scraping side, and the scraping side is arc-shaped. Each scraper support is provided with an independent gap adjustment mechanism, and the gap between each scraper support and the adhesive film is independently adjustable.

5. The hot melt adhesive re-yarn equipment according to claim 1, characterized in that: The glue scraping support plate includes a glue scraping section, a connecting block, and a limiting frame; the gap adjustment mechanism is a lifting servo cylinder. The lifting servo cylinder is mounted on a crossbeam of the frame. A limit frame and a scraping section are provided below the crossbeam. The piston rod of the lifting servo cylinder passes vertically downward through the crossbeam and is fixedly connected to the limit frame. The limit frame is a rectangular frame with a limit block inside. A limit post is also provided at the bottom center of the limit block. The bottom of the limit post passes through the limit frame and is connected to the scraping section. A compression spring is also sleeved inside the limit frame on the periphery of the limit post. A line laser measuring instrument is provided on the side of each scraping section near the electromagnetic heating traction roller group to detect the thickness of the composite material passing through the scraping section area, and the target thickness of the composite material is b.

6. The hot melt adhesive re-yarn equipment according to claim 4, characterized in that: The scraping section is also provided with a main recycling channel, a branch recycling channel, and a collection trough that are connected vertically in sequence on the side near the electromagnetic heating traction roller group. The main recycling channel extends along the width of the adhesive film, has a recycling outlet, and a recycling pipe is installed at the recycling outlet. The collection troughs are multiple and evenly distributed in the lower middle position of the scraping section. The top of each collection trough is connected to the main recycling channel through a recycling branch channel. The bottom of the collection trough extends to the lowest point of the scraping section, and its top extends to the middle of the scraping section. The bottom area of ​​the collection trough is larger than its top area. The bottom of the collection trough has an arc-shaped transition, and its depth gradually decreases from bottom to top. The two side walls of the collection trough are designed in a figure-eight shape. Each of the scraping sections is also equipped with a heating element, which heats the adhesive on the scraping side, as well as in the collection tank, the main recycling channel, and the branch recycling channel, to ensure that the scraped adhesive can be collected smoothly. The temperature of the scraping section is independently controlled and is 5 to 30°C higher than the melting point of the hot melt adhesive film.

7. The hot melt adhesive re-yarn equipment according to claim 1, characterized in that: A flexible contact layer is covered on the scraping side. The flexible contact layer is made of polytetrafluoroethylene, polyurethane rubber or silicone rubber and has a thickness of 1 to 5 mm.

8. The re-yarn process of a hot melt adhesive re-yarn equipment according to any one of claims 1 to 7, characterized in that: include Step 1: Unwinding and tension control of fiberglass yarn; Install the fiberglass yarn spool onto the yarn feeding rack; After being positioned by the carding frame, the fiberglass yarn is flattened by the flattening rollers and then conveyed toward the electromagnetically heated traction roller group; during the unwinding process, the static electricity generated by the fiberglass yarn is eliminated by the static elimination device. Step 2: Film unwinding and servo tension adjustment; The hot melt adhesive film roll is installed on the film unwinding shaft, and the film unwinding tension is adjusted by a servo motor. The closed-loop tension control system detects the film unwinding tension in real time and dynamically adjusts the output torque of the servo motor to keep the film unwinding tension constant. The edge position of the film is detected by the correction device, and the lateral position of the film is adjusted by the correction actuator to align it with the edge of the fiberglass yarn. Step 3: Low-speed thermal bonding using electromagnetically heated traction rollers; The aligned fiberglass yarn and the adhesive film are fed together into the electromagnetic heating traction roller group for thermal bonding; the rotation speed of the electromagnetic heating traction roller is 2~50m / min; the roller surface temperature of the electromagnetic heating traction roller is maintained at 85~115℃ by a PID closed-loop temperature control system; the fiberglass yarn and the adhesive film are fully melted and impregnated on the surface of the electromagnetic heating traction roller; Step 4: Winding and tension control; The composite glass fiber reinforced yarn is guided into the winding mechanism. The winding end adopts a tapered tension control method, and the winding tension gradually decreases as the roll diameter increases. The tapered coefficient is 0.3~0.

7.

9. The hot melt adhesive re-yarn process according to claim 8, characterized in that: It also adopts independent operation and control of each HMI; Independent HMI (Human-Machine Interface) controls key process parameters such as tension, temperature, and speed on the yarn unwinding, film unwinding, and winding sides, replacing the existing method of centralized control of all parameters by a single HMI. Each HMI is connected to the main control system, allowing operators to set, monitor, and adjust process parameters on each side. This enables on-site operation at each workstation without having to travel between the central control panel and the actuators, achieving independent operation and control in each zone.

10. The hot melt adhesive re-yarn process according to claim 8, characterized in that: Between step three and step four, the following steps are also included: S1. After the glass fiber yarn and the adhesive film have been fully melted and impregnated, the composite moves toward the adhesive scraping mechanism. S2. Detect the thickness of the composite material located in each scraping support area that is about to reach the scraping mechanism. When the thickness of the composite material in one or more scraping support areas deviates from the set value b by more than ±0.1mm, start the lifting servo cylinder in the corresponding scraping support area and adjust it to stop when the distance between the scraping plate and the upper surface of the composite material is b±0.05mm. S3. Then, the scraper side is used to scrape the uneven molten adhesive in the area of ​​the scraper support plate, so that the adhesive is evenly distributed on the surface of the glass fiber yarn and in the fiber gaps. At this time, the scraped adhesive is collected through the collection tank, and the adhesive collected in the collection tank is recycled through the recycling support channel, the recycling main channel and the recycling pipe by the vacuum pump. After the uneven molten adhesive in this area is scraped flat, the scraper plate is reset. S4. After the molten adhesive is leveled, the composite is run in a steady flow section with a length of 400-500 mm, and then the composite is cooled and shaped using a cooling roller to obtain a glass fiber yarn mesh reinforced hot melt adhesive composite material with uniform adhesive layer thickness.

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