Tension pre-applying device of bobbin winder and control method

Abstract

The invention relates to the technical field of bobbin winder yarn tension control, provides a bobbin winder tension pre-adding device and a control method, and aims at solving the quality problem caused by tension fluctuation in the spooling process of high-twist-coefficient yarn. The pre-tension device of the bobbin winder comprises a fixed frame, a movable frame, a torque spring, an adjusting nut and a plastic bearing, and the pre-tightening force of the torque spring on the movable frame is changed by rotating the adjusting nut, so that the output tension is adjusted. The device buffers and compensates the tension fluctuation of the yarns by utilizing the rebound resilience of the torque spring, thereby reducing the jittering of the yarns and reducing the probabilities of yarn twisting, yarn mesh and head-climbing defective drums. The control method comprises the steps of winding preparation, yarn placement, tension application, winding, yarn detection, cutting and the like, the stability of the yarn tension is ensured, and the cone yarn quality is improved. The device is simple in structure, low in cost, easy to install and maintain and suitable for various yarn types and process requirements.

Description

Technical Field

[0001] The invention relates to the technical field of yarn tension control of a winding machine, and in particular to a pre-tensioning device of a winding machine. Background Art

[0002] In the textile field, high twist coefficient yarns are more likely to have yarn kinks, mesh yarns, and head-hanging defects during the winding process, which has a great negative impact on the quality of the yarn. The appearance of yarn kinks, mesh yarns, and head-hanging defects is basically related to the tension fluctuations in the high-speed winding process or the splicing cycle process. Therefore, better control of the tension changes in the high-speed winding process and the splicing cycle process to keep it stable is of great significance to eliminate yarn kinks, mesh yarns, and head-hanging defects. High twist coefficient yarn generally refers to medium and high count yarns with ultra-high twist or low count yarns with general twist. Because of the high twist coefficient of both, the fiber aggregates produce a greater reverse force against the twisting force, which is called detwisting force. This internal stress in the yarn will cause a certain section of the unwound yarn to form a kink under insufficient tension. It often occurs in the twisting cycle process and also in the high-speed winding process. The direction of the yarn detwisting force is along the cross-section of the yarn, and in the high-speed winding process, the yarn is in a straightened state and has a certain tension. The tension direction is along the yarn axis. Therefore, when the internal stress (cross-sectional direction) of the yarn generated by the detwisting trend is large enough, it will affect the winding tension (yarn axis), causing tension fluctuations. The yarn will shake in the cross-sectional direction when straightened, increasing the probability of the yarn forming mesh yarn and climbing head defective tubes. The tension fluctuation caused by the internal stress of yarn untwisting during high-speed winding has the following characteristics: frequent, rapid, and unpredictable. Therefore, the tension sensor with tension closed-loop function cannot guarantee timely and accurate judgment to ensure that the tension output device outputs the tension accurately in real time. Ultimately, the winding tension fluctuation causes the yarn to shake, and the bobbin yarn has problems with mesh yarn and climbing heads.

[0003] Patent No. CN 108217336 A introduces a linear yarn pressurizing device, which uses electromagnetic pressure to pressurize the yarn using a grid ceramic sheet, and sets different voltage values ​​to achieve different tension outputs. When the yarn has rapid, irregular and short-lasting tension changes, it is impossible to accurately achieve tension compensation in real time. CN 101920872 B introduces a winding machine tension control device, which uses electromagnetic pressure to pressurize the yarn using a pair of metal disks. The metal disks rotate at a certain speed, and there is a tension instability during the rotation process, and it is impossible to output tension compensation in a timely and accurate manner. CN 105819275 B introduces the use of a pair of ceramic disks to pressurize the yarn through electromagnetic pressure, which overcomes the problem of unstable tension during the rotation process, but still cannot accurately compensate for tension in real time. CN 103359541 B introduces a tensioning device, which uses a fixed deflector and a movable deflector to pressurize the yarn through a linear spring. The linear spring can achieve more real-time and accurate tension compensation for rapid and irregular tension fluctuation pulses, control tension fluctuations, and reduce yarn jitter. The power source for opening and closing the device is a stepper motor, which adds additional costs. EP 1.975.105A2 introduces a wire tensioning device with a spring pressure disk, which can effectively control tensions higher than 0.2-0.3N, but when the tension is lower than this tension, the wire tensioning device of the disk is not accurate enough and not very reliable. Similarly, EP734.990B1 also introduces a wire tensioning device with a magnetic disk, which has the same problem as EP1.975.105A2. CN101759062B introduces a winding machine with two tension control mechanisms, wherein the first tension device is used to control the tension between the unwinding of the tube yarn and the yarn accumulator, and the second tension device is used to control the tension between the yarn accumulator and the tube yarn. For conventional winding machines without an accumulator, it is difficult to achieve this type of tension control or the cost of achieving it is too high.

[0004] In summary, the yarn tension control device in the prior art has obvious deficiencies in dealing with tension fluctuations during high-speed winding, including problems in control accuracy, real-time compensation capability, operation complexity, and cost, etc. These problems directly affect the quality and production efficiency of the yarn. Summary of the invention

[0005] In order to solve the problems existing in the background technology, the present invention provides a pre-tensioning device for a winding machine, which comprises a lower scissor bracket installed on the winding machine, and a device body is installed below the scissor bracket. The device body comprises a fixed frame, a movable frame, a torque spring, an adjusting nut, and a plastic bearing, wherein:

[0006] The fixing frame is fixed on the lower scissor bracket, and the fixing frame is provided with a guide column and a metal support, and the adjusting nut is rotatably sleeved on the guide column of the fixing frame; a limit hole is provided on the upper part of the adjusting nut, and the upper end of the torque spring is connected to the limit hole; by rotating the adjusting nut, the pre-tightening force of the torque spring on the movable frame is changed, and the tension output by the adjusting device is adjusted;

[0007] The plastic bearing is sleeved on the metal support, the torque spring is sleeved on the outside of the plastic bearing, the lower end of the torque spring supports the movable frame, and the upper end is fixed by an adjusting nut;

[0008] The movable frame is also mounted on the plastic bearing and is pushed by the torque spring; when the torque spring is compressed or stretched, the torque spring applies or releases tension to the yarn through the movable frame.

[0009] In a preferred solution, it also includes a limiting stud, which is fixed to the fixed frame through a limiting nut to limit the movable angle of the movable frame.

[0010] In a preferred solution, yarn guide ceramics are installed on both the fixed frame and the movable frame for guiding the yarn to smoothly pass through the pre-tensioning device and reduce the friction between the yarn and the metal parts.

[0011] In a preferred solution, the fixing frame is positioned and fixed on the lower yarn scissors bracket by two screws.

[0012] In a preferred solution, a yarn guide ceramic ring is installed below the scissors bracket.

[0013] A method for controlling the winding tension of a winding machine is carried out according to the following steps:

[0014] S1. Winding preparation:

[0015] Before the yarn winding starts, the opening lever mechanism is actuated to put the scissors in a closed yarn cutting state, and the pre-yarn clearing device is in an open state. At this time, the movable frame of the pre-tensioning device is in an open state under the action of the opening lever mechanism, until the yarn is fed into the pre-tensioning device, the opening lever mechanism is reset, the scissors are opened, the pre-yarn clearing device is closed, and the pre-tensioning device is closed, so that the yarn can be smoothly placed; the yarn is guided to the entrance of the pre-tensioning device, ready to enter the channel formed by the fixed frame and the movable frame;

[0016] S2, yarn placement:

[0017] The movable frame of the pre-tensioning device starts to close; the yarn is placed in the pre-tensioning device and passes through the yarn guide ceramic between the fixed frame and the movable frame;

[0018] S3. Tension application:

[0019] During this process, the torque spring applies a steady thrust to the movable frame, cooperating with the fixed frame to apply additional tension to the yarn;

[0020] S4, Winding:

[0021] The winding machine performs the winding action. During the winding process, the yarn continuously passes through the pre-tensioning device. If the yarn tension fluctuates, the torque spring uses its resilience to buffer and compensate for the tension fluctuation. When the yarn tension tends to be stable, the movable frame of the pre-tensioning device also remains stable, and the output additional tension remains unchanged.

[0022] S5. Yarn detection and cutting:

[0023] During the winding process, if unacceptable defects are detected in the yarn, the yarn will be quickly cut off by the electronic yarn clearer to prevent the defects from entering the bobbin; at this time, the pre-tensioning device continues to maintain its tension output state, waiting for the next yarn to be inserted and the winding process to begin;

[0024] In a preferred embodiment, step S1 further includes the step of adjusting the tension output by the pretensioning device by rotating the adjusting nut to change the preload force of the torque spring according to the type of yarn or process requirements;

[0025] The preferred solution also includes step S6, maintenance and adjustment, and the specific process is as follows: after the winding is completed, the pre-tensioning device is checked, cleaned or adjusted, and the wear of the yarn guide ceramic is checked, and maintenance or replacement is performed according to the wear condition.

[0026] The beneficial effects achieved by the present invention are:

[0027] First, the present invention provides a pre-tensioning device, which has a simple structure and is easy to use. It does not require an additional power source to control the opening and closing of the device, and has a lower cost. After adding the device, the single spindle still maintains the original disc tension, and the additional tension required for winding is mainly output by the original disc tension. The pre-tensioning device relies on the torque spring to provide only a small part of the additional tension to control the yarn tension fluctuation and reduce the yarn shaking; the tension output of the device can be adjusted according to actual conditions. Therefore, all winding tensions include the unwinding tension of the bobbin, the tension generated by friction, the output tension of the disc device, and the tension output by the pre-tensioning device.

[0028] Second, the pre-tension device is installed under the single spindle lower scissor bracket of the winding machine. The single spindle lower scissor opens the rod mechanism, opens when the device needs to be opened to insert the yarn, and closes before the single spindle starts to provide additional tension. It relies on the thrust exerted by the torque spring on the yarn guide ceramic of the device movable frame, and cooperates with the yarn guide ceramic of the fixed frame to apply additional tension to the winding yarn. The torque provided by the torque spring can be adjusted to suit different types of yarns. When the yarn tension remains stable, the pre-tension device movable frame remains stable and the output tension remains unchanged. When the yarn tension fluctuates, this fluctuation may come from the unwinding of the bobbin, friction, yarn internal stress or disc device. Changes in one or several factors lead to unstable tension, and it does not have rapid and accurate tension compensation. The torque spring of the pre-tension device itself has resilience and has a good buffering function for tension fluctuation pulses. After the yarn tension tends to be stable, the pre-tension device movable frame also tends to be stable and resets to a stable tension output position to maintain stable output of additional tension. The function of the pre-tensioning device is to utilize the torsional characteristics of the torsion spring to buffer the tension fluctuations caused by the unwinding of the bobbin, friction, internal stress of the yarn or the disc device during the winding process, provide tension compensation, reduce tension fluctuations, alleviate yarn jitter, and reduce the probability of high twist coefficient yarn kinking, mesh yarn, and head-climbing defects.

[0029] Third, the present invention provides a pre-tensioning device and control method for a winding machine, which can realize the buffering and tension compensation of the winding tension fluctuation pulse, reduce the yarn kinks, mesh yarns, and head-climbing defects, and has the characteristics of being easy to use, low cost, and good effect. It does not require additional power components, such as stepper motors, cylinders, solenoid valves, etc., and uses the opening rod mechanism of the single spindle itself to realize the opening and closing of the device; the torque spring is used to realize the control of the yarn tension by the device movable frame, which has a rapid and accurate buffering and compensation function, and assists the disc device to achieve more stable winding tension control. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the structure of the pre-tensioning device;

[0031] Figure 2 is a schematic diagram of yarn untwisting force;

[0032] Figure 3 It is a schematic diagram of the structure of the pre-tensioning device and the opening rod mechanism;

[0033] Figure 4 is a schematic diagram of the yarn tension state;

[0034] Figure 5 1 is a schematic diagram of the single spindle structure of the winding machine in Example 1;

[0035] Figure 6 It is a schematic diagram of the single spindle winding process in Example 1.

[0036] Numbers in the figure:

[0037] 1. Lower scissor bracket; 2. Fixed bracket; 3. Movable bracket; 4. Torque spring; 5. Adjusting nut; 6. Plastic bearing; 7. Limiting stud; 8. Yarn guide ceramic ring; 9. Metal pressure plate; 10. Yarn guide ceramic; 11. Metal pillar; 12. Retaining ring; 13. Flat washer; 14. Screw; 15. Limiting nut; 16. Pre-tensioning device; 17. Disc device; 18. Cop unwinding tension; 19. Tension generated by each friction point; 20. Internal stress of yarn untwisting; 21. Bobbin; 22. Bobbin cradle; 23. Grooved drum; 24. Electronic yarn clearer; 25. Splicer; 26. Bobbin suction nozzle; 27. Main box; 28. Yarn feeding rod; 29. ​​Lower scissors; 30. Pre-yarn clearing device; 31. Bobbin suction nozzle; 32. Yarn guide; 33. Bobbin; 34. Yarn; 35. Single spindle; 36. Opening rod mechanism. DETAILED DESCRIPTION

[0038] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the present invention. In addition, the forms of the various structures recorded in the following embodiments are merely illustrative, and the present invention is not limited to the various structures recorded in the following embodiments. All other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0039] Reference Figure 1-Figure 5 The present invention provides a pre-tensioning device 16 for a winding machine, comprising a lower scissor bracket 1 installed on the winding machine, a device body is installed below the scissor bracket, and the device body comprises a fixed frame 2, a movable frame 3, a torque spring 4, an adjusting nut 5, and a plastic bearing 6. The fixed frame 2 is fixed on the lower scissor bracket 1, and the fixed frame 2 is provided with a guide column and a metal support 11. The adjusting nut 5 is rotatably sleeved on the guide column of the fixed frame 2; a limiting hole is provided on the upper part of the adjusting nut 5, and the upper end of the torque spring 4 is connected to the limiting hole; by rotating the adjusting nut 5, the pre-tightening force of the torque spring 4 on the movable frame 3 is changed, and the tension output by the adjusting device is adjusted; the plastic bearing 6 is sleeved on the metal support 11, and the torque spring 4 is sleeved on the outside of the plastic bearing 6, the lower end of the torque spring 4 supports the movable frame 3, and the upper end is fixed by the adjusting nut 5.

[0040] The movable frame 3 is also sleeved on the plastic bearing 6 and is subjected to the thrust of the torque spring 4; when the torque spring 4 is compressed or stretched, the torque spring 4 applies or releases tension to the yarn 34 through the movable frame 3. It also includes a limiting component, which includes a limiting stud 7 and a limiting nut 15; the limiting stud 7 is fixed to the fixed frame 2 through the limiting nut 15, and works together with the flat washer 13 to limit the movable angle of the movable frame 3.

[0041] The fixed frame 2 and the movable frame 3 are both provided with yarn guide ceramics 10 for guiding the yarn 34 to pass through the pre-tensioning device 16 smoothly and reducing the friction between the yarn 34 and the metal parts. The fixed frame 2 is positioned and fixed on the lower yarn scissor bracket by two screws 14. A yarn guide ceramic ring 8 is installed below the scissor bracket.

[0042] A method for controlling the winding tension of a winding machine of the present invention is carried out according to the following steps:

[0043] S1. Winding preparation:

[0044] Before the winding starts, the opening rod mechanism 36 is actuated to put the scissors 29 in a closed yarn cutting state, and the pre-clearing device 30 in an open state. At this time, the movable frame 3 of the pre-tensioning device 16 is in an open state under the action of the opening rod mechanism 36, until the yarn is fed into the pre-tensioning device 16, the opening rod mechanism 36 is reset, the scissors 29 are opened, the pre-clearing device 30 is closed, and the pre-tensioning device 16 is closed, so that the yarn 34 can be smoothly placed; the yarn 34 is guided to the entrance of the pre-tensioning device 16, ready to enter the channel formed by the fixed frame 2 and the movable frame 3;

[0045] S2, yarn 34 is placed:

[0046] The movable frame 3 of the pre-tensioning device 16 starts to close; the yarn 34 is placed in the pre-tensioning device 16 and passes through the yarn guide ceramic 10 between the fixed frame 2 and the movable frame 3;

[0047] S3. Tension application:

[0048] During this process, the torque spring 4 applies a steady thrust to the movable frame 3, and cooperates with the fixed frame 2 to apply an additional tension to the yarn 34;

[0049] S4, Winding:

[0050] The winding machine performs a winding action. During the winding process, the yarn 34 continuously passes through the pre-tensioning device 16. If the tension of the yarn 34 fluctuates, the torque spring 4 uses its resilience to buffer and compensate for the tension fluctuation. When the tension of the yarn 34 tends to be stable, the movable frame 3 of the pre-tensioning device 16 also maintains a stable state, and the output additional tension remains unchanged.

[0051] S5, yarn 34 detection and cutting:

[0052] During the winding process, if unacceptable defects are detected in the yarn 34, the yarn 34 is quickly cut off by the electronic yarn clearer 24 to prevent the defects from entering the bobbin 21; at this time, the pre-tensioning device 16 continues to maintain its tension output state, waiting for the next yarn 34 to be inserted and the winding process to start;

[0053] Step S1 also includes a step of adjusting the tension output by the pretensioning device 16 by rotating the adjusting nut 5 to change the preload force of the torque spring 4 according to the type of the yarn 34 or the process requirements.

[0054] It also includes step S6, maintenance and adjustment, and the specific process is as follows: after the winding is completed, the pre-tensioning device 16 is checked, cleaned or adjusted, and the wear of the yarn guide ceramic 10 is checked, and maintenance or replacement is performed according to the wear.

[0055] Embodiment 1, in this embodiment, the spindle is first explained. In the field of textile machinery, especially in an automatic winding machine, a single spindle 35 refers to an independent working unit on the winding machine. Each single spindle 35 can independently complete the winding process of the yarn 34, including the introduction of the yarn 34, tension control, winding into a cone and other steps. In an automatic winding machine, there are usually multiple single spindles 35 working in parallel to improve production efficiency and output.

[0056] In this embodiment, each single spindle 35 is an independent winding unit, which can independently complete the whole process from introducing the yarn 34, adjusting the tension to winding into a cone. The single spindle 35 is equipped with a tension control device, such as a disc tension device and a pre-tension device 16, which is used to control the tension of the yarn 34 during the winding process to ensure the tightness and uniformity of the winding of the yarn 34. An automatic winding machine is usually equipped with multiple single spindles 35, which can work in parallel and simultaneously carry out the winding process of multiple yarns 34, thereby greatly improving the overall production efficiency.

[0057] In this embodiment, 24-spindle 1450 twist / m strong twist yarn is used, and the pre-tension device 16 is installed below the disc tension device 17 of the single spindle 35 structure of the winding machine, and is fixed to the main box 27 through the lower scissor bracket 11. The opening and closing of the movable frame 3 of the pre-tension device 16 shares the opening rod mechanism 36 of the lower scissor 29 / pre-clearing yarn 30, and the opening angle of the movable frame 3 is between 20°-40°, which is convenient for inserting the yarn 34.

[0058] The distance between the upper and lower ceramic centers of the movable frame 3 should be 18-22mm. The torque spring 4 is a left-handed spring with 20 effective turns and a certain torque. In this embodiment, the adjusting nut 5 is a regular hexagon with no threads in the hole and a through hole with a diameter of 0.7-1mm at one corner. The plastic bearing 6 has a self-lubricating function. The length of the limit stud 7 is between 16-20mm. The surface roughness Ra of the yarn guide ceramic 10 yarn guide arc surface should be between 0.3-0.4.

[0059] The metal support 11 has a special boss in the middle, which separates the upper adjustment nut 5 from the lower plastic bearing 6 and restricts the adjustment nut 5 from axial movement along the metal support 11. The pre-tension device 16 should be centered on the yarn path to ensure that the yarn guide point of the pre-tension device 16 coincides with the yarn path in four directions. In order to ensure the consistency of the winding tension, after installing the pre-tension device 16, the tension output of the disc device 17 is appropriately lowered by 10%-15%.

[0060] like Figure 5 As shown, when the single spindle 35 is started, the yarn head of the cop 33 is blown to the top of the yarn guide 32 by air, the cop suction nozzle 31 captures the yarn 34, the disc device 17 is opened, the opening rod mechanism 36 is actuated, the pre-tensioning device 16, the disc device 17, and the pre-clearing device 30 are opened, and the lower scissors 29 are closed to cut the yarn. The tube suction nozzle 26 approaches the tube 21 fixed on the tube cradle 22, the groove drum 23 rotates in the opposite direction, the tube suction nozzle 26 captures the yarn head, pulls the yarn 34 downward and feeds it into the splicer 25, the tube suction nozzle 31 pulls the yarn 34 upward, the yarn feeding rod 28 swings to feed the yarn 34 into the splicer 25, the disc device 17 is closed, the opening rod mechanism 36 is actuated, the pre-tensioning device 16 and the pre-clearing device 30 are closed, and the lower scissors 29 are opened. At this time, the yarn 34 has been synchronously placed in the pre-clearing device 30, the pre-tensioning device 16 and the disc device 17. The splicer 25 completes the yarn 34 joint, and the single spindle 35 starts to wind the yarn. When unacceptable defects are detected in the yarn 34, the electronic yarn clearer 24 cuts off the yarn 34 and enters the next cycle.

[0061] The magnitude of the pre-tension is adjusted in multiple stages by adjusting the nut 5. The pre-tension device 16 can be adjusted according to the type of yarn 34 actually spun. Generally, the lower the yarn count, the higher the tension output of the pre-tension device 16, and the higher the yarn count, the lower the tension output. Figure 3 The source of the tension of the yarn 34 is shown in the figure, including the unwinding tension 18 of the bobbin, the tension 19 generated by each friction point, the internal stress 20 of the yarn untwisting, the additional tension provided by the disk device 17 and the additional tension provided by the pre-tensioning device 16.

[0062] Before and after the installation of the pre-tensioning device 16, the good bobbin rate of the bobbin yarn 21 is increased from 90%-95% to 99%-99.5%, the yarn 34 in the bobbin has no kinks, and there is no mesh yarn on the end surface of the bobbin yarn 21. The production efficiency is increased by 3%-5%, the output is increased by 2%-4%, and the number of broken ends per million meters in the next warping process is reduced from 0.8-1.2 to 0.4-0.5.

[0063] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A pre-tensioning device for a winding machine, characterized in that: It includes a lower scissor bracket installed on the winding machine, and a device body is installed below the scissor bracket. The device body includes a fixed frame, a movable frame, a torque spring, an adjusting nut, and a plastic bearing, wherein: The fixing frame is fixed on the lower scissor bracket, and the fixing frame is provided with a guide column and a metal support, and the adjusting nut is rotatably sleeved on the guide column of the fixing frame; a limit hole is provided on the upper part of the adjusting nut, and the upper end of the torque spring is connected to the limit hole; by rotating the adjusting nut, the pre-tightening force of the torque spring on the movable frame is changed, and the tension output by the adjusting device is adjusted; The plastic bearing is sleeved on the metal support, the torque spring is sleeved on the outside of the plastic bearing, the lower end of the torque spring supports the movable frame, and the upper end is fixed by an adjusting nut; The movable frame is also mounted on the plastic bearing and is pushed by the torque spring; when the torque spring is compressed or stretched, the torque spring applies or releases tension to the yarn through the movable frame.

2. The pre-tensioning device of the winding machine according to claim 1, characterized in that: It also includes a limiting stud, which is fixed to the fixed frame through a limiting nut to limit the movable angle of the movable frame.

3. The pre-tensioning device of the winding machine according to claim 1, characterized in that: Yarn guide ceramics are installed on both the fixed frame and the movable frame to guide the yarn to pass through the pre-tension device smoothly and reduce the friction between the yarn and the metal parts.

4. The pre-tensioning device for a winding machine according to claim 1, characterized in that: The fixing frame is positioned and fixed on the lower yarn scissors bracket by two screws.

5. The pre-tensioning device for a winding machine according to claim 1, characterized in that: A yarn guide ceramic ring is installed below the scissor bracket.

6. A method for controlling winding tension of a winding machine, characterized in that: The winding machine pre-tensioning device according to any one of claims 1 to 4 is used and carried out in the following steps: S1. Winding preparation: Before the yarn winding starts, the opening lever mechanism is actuated to put the scissors in a closed yarn cutting state, and the pre-yarn clearing device is in an open state. At this time, the movable frame of the pre-tensioning device is in an open state under the action of the opening lever mechanism, until the yarn is fed into the pre-tensioning device, the opening lever mechanism is reset, the scissors are opened, the pre-yarn clearing device is closed, and the pre-tensioning device is closed, so that the yarn can be smoothly placed; the yarn is guided to the entrance of the pre-tensioning device, ready to enter the channel formed by the fixed frame and the movable frame; S2, yarn placement: The movable frame of the pre-tensioning device starts to close; the yarn is placed in the pre-tensioning device and passes through the yarn guide ceramic between the fixed frame and the movable frame; S3. Tension application: During this process, the torque spring applies a steady thrust to the movable frame, cooperating with the fixed frame to apply additional tension to the yarn; S4, Winding: The winding machine performs the winding action, during which the yarn continuously passes through the pre-tensioning device; If the yarn tension fluctuates, the torque spring uses its resilience to buffer and compensate for the tension fluctuation; when the yarn tension tends to be stable, the movable frame of the pre-tensioning device also remains stable, and the output additional tension remains unchanged; S5. Yarn detection and cutting: During the winding process, if unacceptable defects are detected in the yarn, the yarn will be quickly cut off by the electronic yarn clearer to prevent the defects from entering the bobbin; at this time, the pre-tensioning device continues to maintain its tension output state, waiting for the next yarn to be inserted and the winding process to begin.

7. A winding tension control method for a winding machine according to claim 6, characterized in that: Step S1 also includes a step of adjusting the tension output by the pretensioning device by rotating the adjusting nut to change the preload force of the torque spring according to the type of yarn or process requirements.

8. A winding tension control method for a winding machine according to claim 6, characterized in that: It also includes step S6, maintenance and adjustment, and the specific process is as follows: after the winding is completed, the pre-tensioning device is checked, cleaned or adjusted, and the wear of the yarn guide ceramic is checked, and maintenance or replacement is performed according to the wear.

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