Heavy yarn roll constant tension yarn feeding system

Abstract

The utility model discloses a heavy type yarn roll constant tension yarn feeding system, including support, the support at least one side is equipped with vertical installation surface, a plurality of yarn feeding units are arranged with dot matrix array form on the vertical installation surface, and a plurality of yarn feeding units lead to the same side and constitute multichannel yarn, and the yarn lead-out path of each yarn feeding unit is provided with a first yarn guide wheel on the side, and each yarn is gathered to a shared second yarn guide wheel after passing through the corresponding first yarn guide wheel, and the spatial position of a plurality of first yarn guide wheels is completely same with respect to the corresponding yarn feeding unit axis. The utility model discloses a first yarn guide wheel of one-to-one and completely same spatial position setting can significantly improve the yarn tension consistency of multichannel yarn, and is favorable to realize the constant tension closed loop control of heavy type yarn roll.

Description

Technical Field

[0001] This utility model relates to the field of textile machinery technology, and in particular to a heavy-duty yarn roll constant tension unwinding system. Background Technology

[0002] In textile processing, maintaining constant tension while unwinding yarn from the bobbin is crucial, especially for heavy yarn spools (e.g., 10-100 kg). Uneven tension directly leads to product defects. Existing multi-yarn unwinding technologies often suffer from the following problems: inconsistent yarn guide paths in each unwinding unit result in significant differences in friction between yarns and poor tension uniformity; as the yarn spool radius decreases sharply, the wrap angle between the yarn and the guide roller undergoes complex changes, introducing unpredictable tension disturbances; and the control strategy is complex, requiring individual parameter adjustments for each channel, making maintenance difficult. Therefore, there is an urgent need for an unwinding device that can ensure consistent and stable tension for all yarns. Summary of the Invention

[0003] Purpose of the invention: In order to overcome the shortcomings of the existing technology, this utility model provides a constant tension yarn feeding system for heavy-duty yarn rolls. By setting the first yarn guide rollers in a one-to-one and identical spatial position, the tension consistency of multiple yarns can be significantly improved, which is conducive to realizing constant tension closed-loop control of heavy-duty yarn rolls.

[0004] Technical Solution: To achieve the above objectives, this utility model provides a heavy-duty yarn roll constant tension unwinding system, comprising a support frame. At least one side of the support frame has a vertical mounting surface. Multiple unwinding units are arranged in a dot matrix array on the vertical mounting surface. These multiple unwinding units extend to the same side to form multiple yarn paths. A first yarn guide wheel is correspondingly provided beside the yarn path of each unwinding unit. After being unwinded from the yarn roll, each yarn path first bypasses the corresponding first yarn guide wheel and then converges to a shared second yarn guide wheel. The spatial positions of the multiple first yarn guide wheels relative to the axis of their corresponding unwinding units are completely identical.

[0005] Furthermore, the yarn feeding unit includes a sleeve shaft for fixing the yarn bobbin; the sleeve shaft is connected to the drive motor via a transmission mechanism.

[0006] Furthermore, the first guide roller is located obliquely above the yarn bobbin lead-out side to form a consistent initial yarn path.

[0007] Furthermore, multiple sets of the yarn feeding units are arranged horizontally to form a horizontal row of yarn feeding units; each row of yarn feeding units has a third yarn guide wheel downstream, and the axis of the third yarn guide wheel is located on the same horizontal straight line as the axis of all the first yarn guide wheels in the same row, so that when all the yarns in the row are guided from the first yarn guide wheel to the third yarn guide wheel, their lead-out directions are absolutely parallel and consistent.

[0008] Furthermore, a tension sensor is installed on each yarn path, located between the third guide wheel and the second guide wheel. The signal output terminal of the tension sensor is connected to a controller, and the control signal output terminal of the controller is connected to the driver of the drive motor, thereby forming a closed-loop constant tension control system.

[0009] Furthermore, the drive motor is a servo motor or a torque-controllable motor.

[0010] Furthermore, the transmission mechanism includes a first synchronous pulley connected to the rotating shaft of the drive motor, and a second synchronous pulley connected to the bushing shaft, wherein the first synchronous pulley and the second synchronous pulley are connected by a synchronous belt drive.

[0011] Furthermore, the bushing shaft is an air-expanding shaft.

[0012] Beneficial effects: The heavy-duty yarn roll constant tension unwinding system of this utility model has at least the following advantages:

[0013] 1. By setting each first guide roller in exactly the same spatial position, the trend and amplitude of the wrap angle change between the yarn and the first guide roller are ensured to be highly consistent during the unwinding process of each unwinding unit from a full roll to an empty roll. This unifies the originally different and complex path friction disturbances into a predictable and uniform disturbance pattern, laying a solid foundation for unified control.

[0014] 2. Since the mechanical environment of all yarn channels is highly consistent, the controller can use the same set of optimal PID parameters to perform constant tension control on the entire yarn feeding array, which greatly simplifies the debugging, optimization and maintenance work and avoids the tedious task of setting parameters for each channel individually.

[0015] 3. A consistent mechanical path combined with a unified control strategy can significantly reduce tension differences between yarns along different paths, ensuring the uniformity of the final product.

[0016] 4. Predictable disturbances enable the application of advanced algorithms such as feedforward control. The controller can incorporate a unified "wrap angle-wrap diameter" compensation curve to perform feedforward compensation for all channels, further improving control accuracy and response speed.

[0017] 5. The one-to-one guide roller arrangement is independent and robust, which can effectively suppress the vibration generated when heavy yarn rolls start and stop, providing mechanical protection for stable tension. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structural layout and yarn path within the vertical mounting surface of this utility model embodiment;

[0019] Figure 2 for Figure 1 A top-view cross-sectional view of a single yarn feeding unit in the embodiment. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings.

[0021] As attached Figure 1-2 The heavy-duty yarn roll constant tension unloading system includes a support 1. Two parallel vertical surfaces of the support 1 are both vertical mounting surfaces. Multiple unloading units 2 are arranged in a dot matrix array on these vertical mounting surfaces. Figure 1 Nine yarn feeding units 2 are installed in a 3x3 matrix, and multiple yarn feeding units 2 are led out to the same side (to the left in the figure) to form multiple yarns.

[0022] The yarn feeding unit 2 includes a sleeve shaft 21 for fixing the yarn bobbin 5; the sleeve shaft 21 is connected to the drive motor 7 via a transmission mechanism 6.

[0023] Preferably, the drive motor is a servo motor or a torque-controllable motor, capable of operating in torque control mode. The mounting shaft 21 is an air-expanding shaft to provide sufficient clamping force to prevent slippage of heavy yarn bobbins.

[0024] Preferably, the transmission mechanism 6 includes a first synchronous pulley 61 connected to the rotating shaft of the drive motor 7, and a second synchronous pulley 62 connected to the bushing shaft 21. The first synchronous pulley 61 and the second synchronous pulley 62 are connected by a synchronous belt 63.

[0025] The yarn guide roller is a common guiding component in the yarn unwinding frame. During the unwinding process, the radius of the yarn roll gradually decreases, causing the wrap angle between the yarn and the yarn bobbin surface to change dynamically. This wrap angle is one of the main sources of friction. If the yarn guide roller is not installed, this source of friction is unstable and unpredictable, which will cause difficulties in controlling the constant tension of the yarn.

[0026] In general, this problem can be effectively solved by adding a yarn guide wheel. The yarn guide wheel can lock the yarn path, thus dividing the total friction force into two main components: a variable part and a constant part. The variable part is the friction force generated by the changing wrap angle between the yarn and the surface of the yarn bobbin. Although this part still exists, its absolute value is usually relatively small and negligible. The constant part is the friction force generated by the constant wrap angle between the yarn and the fixed yarn guide wheel. This part becomes the dominant and stable friction source.

[0027] The key lies in the fact that although the friction in the yarn bobbin varies, the guide roller provides a large and stable friction component. This transforms the frictional characteristics of the entire system from a "completely uncontrollable variable" to a "basically stable state with only minor fluctuations." This significantly reduces the difficulty for the control system.

[0028] However, the wrap angle between the yarn and the fixed guide roller is not completely constant. Under normal circumstances, most yarn rolls are unwound, resulting in a very small change in the wrap angle between the yarn and the guide roller, which can be ignored in engineering or easily compensated for by the control system. But for heavy yarn rolls, the radius changes drastically from a full roll to an empty roll. This makes the change in the wrap angle on the guide roller no longer negligible, but a significant factor that must be considered. Therefore, when dealing with heavy yarn rolls with large diameter variations, engineers typically employ more advanced strategies to counteract the impact of wrap angle changes.

[0029] However, traditional guide roller placement lacks a unified and standardized layout, often exhibiting a more arbitrary approach. Traditional methods may include: multiple yarn rolls sharing a single large guide roller; arbitrarily installing guide rollers based on available space; and asymmetrical guide paths across different channels. If the position, angle, and distance of the guide rollers vary in each channel, the wrap angle variation curve will also differ. Tension may increase by 10% in some channels, 15% in others, or even increase initially and then decrease in still others. This leads to a complete loss of tension uniformity among the yarns. Furthermore, due to the chaotic placement, almost every channel requires individual PID parameter tuning, resulting in a massive workload and difficult maintenance (e.g., readjustment is needed after replacing parts).

[0030] To address the aforementioned technical challenges, this solution proposes improvements:

[0031] A first guide roller 3 is correspondingly installed beside the yarn lead-out path of each yarn feeding unit 2. After each yarn is drawn out from the yarn roll, it first passes around the corresponding first guide roller 3 and then converges to a shared second guide roller 4. The spatial positions of the multiple first guide rollers 3 relative to the axis of their corresponding yarn feeding unit 2 are exactly the same. This one-to-one arrangement usually means that each guide roller has a sturdy, independent mounting support. This is crucial for heavy yarn rolls, as it can prevent vibration and structural deformation caused by high yarn tension and inertia. A stable mechanical structure is a prerequisite for stable tension.

[0032] like Figure 2As shown, the support 1 includes several square steel columns 11. A plate is fixedly installed on two parallel surfaces of each square steel column 11. The two plates are combined to form a lateral cantilever. A bearing is installed on each of the two plates, supporting a horizontal shaft of the air shaft. The other end of the horizontal shaft is connected to a synchronous belt drive mechanism. Another plate is fixedly installed on the outside of the synchronous belt drive mechanism, and the drive motor 7 is fixedly installed on the outside of the plate. The total weight of the drive mechanism and the drive motor balances the heavy yarn roll on the other side of the column, making the overall structure of the support more stable and greatly increasing its support strength. It can accommodate yarn rolls weighing more than 10-100 kg. The bearings can be self-aligning bearings, capable of adaptive shaft centering.

[0033] Preferably, the first guide roller 3 is located obliquely above the yarn bobbin lead-out side to form a consistent initial yarn path, that is, in the fully wound state, the path of each yarn from the yarn bobbin to the corresponding first guide roller is consistent.

[0034] More preferably, multiple sets of the yarn feeding units 2 are arranged in a transverse direction to form a transverse row of yarn feeding units; each row of yarn feeding units 2 has a third yarn guide wheel downstream, and the axis of the third yarn guide wheel is located on the same horizontal straight line as the axis of all the first yarn guide wheels 3 in the same row, so that when all the yarns in the row are guided from the first yarn guide wheel 3 to the third yarn guide wheel, their lead-out directions are absolutely parallel and consistent.

[0035] As attached Figure 1 As shown in the illustration, in this embodiment, each of the three rows of yarn feeding units 2 has a third yarn guide roller on its left side. The axis of each third yarn guide roller is strictly aligned with the axes of the three first yarn guide rollers 3 in the same row on the same horizontal line. This ensures that the yarn in the same row is guided from the first yarn guide roller 3 to the third yarn guide roller in a completely parallel path. All yarns eventually converge to a shared second yarn guide roller 4 and enter the subsequent process.

[0036] The key improvement is that a first guide roller 3 is precisely installed diagonally above the lead-out side of each yarn tube 5. Figure 1 In this embodiment, the spatial coordinates (relative to the center of their corresponding air shaft 21) of the nine first guide rollers 3 are identical. After the yarn is drawn out from the yarn bobbin 5, it wraps around the corresponding first guide roller 3 with a certain wrap angle. By setting each first guide roller 3 in the exact same spatial position, it is ensured that the wrap angle change trend and amplitude between the yarn and the first guide roller 3 are highly consistent during the unwinding process of each unwinding unit 2 from a full roll to an empty roll. This unifies the originally different and complex path friction disturbances into a predictable and uniform disturbance pattern, laying a solid foundation for unified control.

[0037] Based on the above improvements, compared with the existing technology, this solution is more suitable for unwinding heavy yarn rolls. From full roll to empty roll, the geometry of the guide path (the path between the yarn bobbin and the first guide wheel) of each yarn roll changes in the same way. Therefore, the wrap angle of the guide wheel in each channel increases with the same trend and magnitude.

[0038] This means that the geometric perturbation experienced by the tension in all channels is exactly the same. Although the tension in each channel tends to increase slowly as the roll diameter decreases, the relative tension difference between them remains very stable. Furthermore, because the mechanical environment of all yarn channels is highly consistent, the controller can use the same set of optimal PID parameters to perform constant tension control on the entire unwinding array, greatly simplifying debugging, optimization, and maintenance, and avoiding the tedious task of individually tuning parameters for each channel.

[0039] Based on this, engineers can accurately measure or calculate a typical "guide wheel wrap angle - coil diameter" relationship curve. This curve is then used as a feedforward compensation model and written into the controller. This model can be used for all channels, adjusting the drive motor torque in advance to counteract tension drift caused by changes in wrap angle. Due to system consistency, this feedforward compensation is effective for all channels, significantly reducing the cost of establishing a feedforward model.

[0040] To achieve high-precision control, a tension sensor, which can be a three-roll tension sensor, is installed on each yarn path between the third guide roller and the second guide roller 4. The signal output terminal of the tension sensor is connected to a controller, and the control signal output terminal of the controller is connected to the driver of the drive motor 7, thus forming a closed-loop constant tension control system. The tension sensor transmits the real-time detected tension signal to the PLC controller. The PLC controller compares the measured tension value with the set value, performs calculations using a PID algorithm, and then sends a control command to the servo driver to adjust the output torque of the drive motor 7, thereby forming a closed-loop control to maintain constant yarn tension.

[0041] In summary, this solution transforms complex and varied disturbances into uniform and predictable disturbances by arranging guide rollers in a "one-to-one, same position" configuration. This allows for the effective implementation of advanced control strategies, ultimately ensuring the uniformity and stability of multi-yarn tension. This is a technical solution that removes complexity from the control process and addresses it in advance through mechanical design.

[0042] The above are merely preferred embodiments of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this utility model, and these improvements and modifications should also be considered within the protection scope of this utility model.

Claims

1. A heavy-duty yarn roll constant tension unwinding system, characterized in that: Includes a bracket (1), the bracket (1) has a vertical mounting surface on at least one side, and multiple yarn feeding units (2) are arranged in a dot matrix array on the vertical mounting surface, and the multiple yarn feeding units (2) are led out to the same side to form multiple yarns; A first guide wheel (3) is provided on the side of the yarn lead-out path of each yarn feeding unit (2); after each yarn is led out from the yarn roll, it first passes around the corresponding first guide wheel (3) and then converges to a common second guide wheel (4). The spatial positions of the multiple first yarn guide rollers (3) relative to the axis of their corresponding yarn feeding unit (2) are exactly the same.

2. The heavy-duty yarn roll constant tension unwinding system according to claim 1, characterized in that: The yarn feeding unit (2) includes a sleeve shaft (21) for fixing the yarn bobbin (5); the sleeve shaft (21) is connected to the drive motor (7) through a transmission mechanism (6).

3. The heavy-duty yarn roll constant tension unwinding system according to claim 2, characterized in that: The first guide roller (3) is located obliquely above the yarn tube lead-out side to form a consistent initial yarn path.

4. The heavy-duty yarn roll constant tension unwinding system according to claim 3, characterized in that: Multiple sets of the yarn feeding units (2) are arranged in a horizontal direction to form a horizontal row of yarn feeding units; each row of yarn feeding units (2) has a third yarn guide wheel downstream. The axis of the third yarn guide wheel is on the same horizontal straight line as the axis of all the first yarn guide wheels (3) in the same row, so that when all the yarns in the same row are led from the first yarn guide wheel (3) to the third yarn guide wheel, their lead-out directions are absolutely parallel and consistent.

5. The heavy-duty yarn roll constant tension unwinding system according to claim 4, characterized in that: On each yarn, a tension sensor is provided on the path between the third guide wheel and the second guide wheel (4). The signal output terminal of the tension sensor is connected to a controller, and the control signal output terminal of the controller is connected to the driver of the drive motor (7), thereby forming a closed-loop constant tension control system.

6. The heavy-duty yarn roll constant tension unwinding system according to claim 2, characterized in that: The drive motor is a servo motor or a torque-controllable motor.

7. A heavy-duty yarn roll constant tension unwinding system according to claim 2, characterized in that: The transmission mechanism (6) includes a first synchronous pulley (61) connected to the rotating shaft of the drive motor (7) and a second synchronous pulley (62) connected to the bushing shaft (21). The first synchronous pulley (61) and the second synchronous pulley (62) are connected by a synchronous belt (63).

8. The heavy-duty yarn roll constant tension unwinding system according to claim 2, characterized in that: The sleeve shaft (21) is an air-expanding shaft.

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