Motor-driven yarn constant-tension let-off device based on sensor feedback

Abstract

The invention discloses a motor-driven yarn constant-tension let-off device based on sensor feedback, relates to the technical field of textile machinery, and is suitable for weaving high-performance fiber high-thickness multi-layer fabrics. The let-off device comprises a control unit and let-off units, wherein the let-off units are modularly arranged, and let-off channels of the let-off units are independently arranged; the let-off unit comprises a torque motor, a guide mechanism, a tension detection mechanism and a spring buffer mechanism. Closed-loop control is formed through driving of a torque motor, real-time feedback of a tension detection mechanism and absorption of instantaneous tension impact by matching with a spring buffer mechanism, and independent regulation and control and constant tension of a single warp / each layer of warp are achieved. The problems that high-performance fibers are prone to breakage due to tension fluctuation and high-thickness multi-layer fabric let-off is difficult to accurately match are effectively solved, and the weaving efficiency and the product percent of pass are improved.

Description

Technical Field

[0001] This invention relates to the field of textile machinery technology, and specifically to a motor-driven constant tension yarn feeding device based on sensor feedback. Background Technology

[0002] High-performance fibers generally exhibit high rigidity and low elongation at break. For example, the elongation at break of carbon fiber is typically only 1.5% to 2%. Even minor tension fluctuations can lead to yarn stretching damage, thinning of the yarn diameter, or even direct breakage. When faced with disturbances such as dynamic changes in roll diameter and nonlinear friction, problems such as adjustment lag and large overshoot are prone to occur, with tension fluctuations reaching 15% to 20%. Therefore, traditional warp feeding methods have inherent defects of low sensitivity and limited adjustment range, and cannot meet the stringent requirements of high-performance fibers for constant tension. For thick, multi-layered fabrics, different types of warp yarns, such as ground warp, skein warp, and pile warp, have refined and differentiated requirements for warp feeding due to differences in weaving paths and interlacing frequencies. Traditional warp feeding systems often use a single main shaft or simple zoned warp feeding mode, lacking independent control units, and cannot achieve precise matching of warp feeding amounts for each layer of warp yarns. Even with techniques that adjust the warp feed rate to change thickness, these techniques are only suitable for medium-thickness fabrics below 20mm. When the target thickness exceeds 30mm, a feed rate adjustment error of ≥5% is insufficient to meet the requirements of uniform interlayer density for thicker structures, easily leading to localized excessively loose or tight fabrics and affecting the consistency of the composite material's mechanical properties. Regarding warp tension stability, high-performance fibers are extremely sensitive to tension fluctuations; a deviation exceeding ±3% can cause changes in elastic modulus and a decrease in breaking strength. Traditional warp feed methods using mechanical transmission tension adjustment mechanisms such as weighted or spring-loaded mechanisms have slow response speeds and are difficult to adapt to the complexities of multi-layer weaving. In multi-layer weaving, the warp paths are long and there is significant mutual interference, making tension transmission prone to lag and coupling interference. When warp density changes or the weft position is dynamically adjusted during weaving, traditional mechanisms cannot quickly balance the tension of each layer, resulting in uneven warp arrangement and inconsistent tension. This not only causes surface wrinkles and warp misalignment but also increases the risk of warp breakage, reducing production efficiency by 15%-30% and achieving a product qualification rate of less than 70%.

[0003] The lack of adaptability in the mechanism further exacerbates the technical difficulties. The design of traditional warp feeding mechanisms is highly tied to the weaving process of single-layer or simple multi-layer fabrics. The power transmission method, response speed, and control logic cannot be matched with the new structures such as multiple weft holes and multiple rapiers required for high-thickness multi-layer weaving. Multi-layer integrated weaving requires multiple weft holes to work synchronously to achieve interlayer weaving, but traditional warp feeding mechanisms lack a linkage control mechanism with the dynamic response of multiple weft holes. They cannot accurately allocate the warp feed amount according to the real-time weaving progress of each weft hole, and their rigid mechanical structure is difficult to adapt to the high-speed reciprocating motion of rapier weft insertion, which easily leads to warp feeding delays or over-feeding, resulting in decreased weft hole stability and failure to achieve accurate forming of multi-layer fabric structures. Ultimately, this restricts the large-scale application of high-thickness multi-layer fabric weaving technology. The above problems are intertwined, ultimately causing a series of quality problems such as unclear weft holes, failed weft insertion, and uneven fabric density, which seriously restricts the improvement of the industrialization level of high-performance inorganic fiber three-dimensional fabrics. Existing warp feeding technologies cannot effectively meet the "multi-path, variable tension, and independent controllable" collaborative warp feeding requirements unique to multi-layer open-face looms. Traditional warp beam feeding uses a collective control mode of "one beam, multiple yarns", which cannot achieve independent control of a single warp yarn; while yarn frame feeding has flexible path control, the equipment is bulky, and its passive tension control mechanism is slow to respond, cannot provide constant tension, and lacks precision.

[0004] Chinese Patent No. CN103343418A discloses a warp feeding device suitable for weaving non-bending fabrics. It describes a warp feeding system with an ultra-large capacity capable of weaving 20,000 strands of 30-layer carbon fiber three-dimensional fabric, including a servo motor-driven 60-axis linkage warp feeding device. This solves the problems of ultra-large capacity continuous flat warp feeding and damage during continuous carbon fiber weaving. US Patent No. US9181064B2 discloses a yarn warp feeding method and device with constant tension and speed. In this system, the yarn unwinds from the spool and engages with a rotating component. A tension sensor detects the warp tension in real time, while a speed sensor synchronously monitors the warp speed. The detected data is transmitted to a control unit, employing a dual closed-loop control logic of "constant tension first, then constant speed"—the control unit first continuously adjusts the tension to a set value, and then locks the warp speed after the tension stabilizes. The entire control process does not require synchronization with the main motion of the textile machinery. However, this device has certain limitations in the use of thick and multi-layered fabrics: it only starts speed control after the tension is completely stable, and speed adjustment is prone to lag due to instantaneous tension fluctuations during high-speed weaving, making it unable to cope with dynamic tension changes in high-performance fibers (such as carbon fibers); similarly, for the flexible adjustment mechanism of high-rigidity, low breaking elongation high-performance fibers, excessive overshoot is prone to occur during tension adjustment, leading to fiber damage.

[0005] In view of this, in order to address the above technical requirements, developing an effective and stable "sensor-motor" coordinated control warp feeding device is crucial for realizing the weaving of high-performance fiber, thick, multi-layered fabrics. Summary of the Invention

[0006] In view of the technical problems existing in the background art, the present invention provides a motor-driven constant tension yarn feeding device based on sensor feedback. This device employs a "motor-sensor" collaborative operation to maintain a stable tension in the yarn during the feeding process, avoiding problems such as yarn slack, tangling, breakage, and structural damage caused by unstable tension. This improves yarn processing quality and production efficiency, meeting the high-precision control requirements of modern textile processes for yarn tension. Simultaneously, it enhances the adaptability of the feeding mechanism to different types and specifications of yarn, further improving processing quality, resulting in uniform fabric formation quality, and reducing warp breaks and weaving defects.

[0007] In a first aspect, embodiments of the present invention provide a motor-driven constant tension yarn feeding device based on sensor feedback, comprising a control unit and modularly arranged feeding units with independently configured feeding channels; the feeding unit includes: A torque motor, controlled by the control unit, is used to provide conveying power for the yarn; The guiding mechanism includes multiple guide rollers, and the yarn passes around each guide roller in sequence to form a tension detection and buffering path; The tension detection mechanism is located at the tail of the guide roller and is used to detect the yarn tension in real time and generate a signal to be fed back to the control unit. A spring buffer mechanism, connected to and cooperating with the guide roller, is used to absorb the impact through its own deformation when the yarn tension increases instantaneously; The control unit receives signals from the tension detection mechanism and compares them with a preset tension value. Based on the comparison result, it dynamically adjusts the output torque or rotation direction of the torque motor to maintain constant yarn tension, thus forming a closed-loop tension control.

[0008] As a further improvement of the present invention, the spring buffer mechanism includes: Slide rails provide a directional sliding path; The connecting block has one end connected to the shaft of the guide roller via a bearing, and the other end slidably engaged with the slide rail; An elastic device, connected to the connecting block, provides a restoring elastic force to the guide roller; When the instantaneous tension of the yarn exceeds the preset tension value, the guide roller compresses or stretches the elastic device and moves along the slide rail to release the tension.

[0009] As a further improvement of the present invention, multiple guide rollers are arranged in an alternating pattern to form an S-shaped winding path, so that the force exerted on the guide rollers by the yarn is opposite in direction when the yarn winds around; when the instantaneous tension of the yarn is too high, the upper guide roller moves downward while the lower guide roller moves upward, working together to quickly release the peak tension in the yarn.

[0010] As a further improvement of the present invention, the control unit adopts a multi-axis synchronous control strategy, simultaneously controlling the torque motors of multiple warp feed units. Multiple drive motors of different warp layers or warp feed units maintain consistency in key parameters such as speed and torque output, achieving a control method that enables synchronous operation of each axis.

[0011] As a further improvement of the present invention, the tension detection mechanism is a high-precision pressure sensor integrated inside the guide roller; the pressure sensor converts the pressure signal of the yarn on the guide roller into an electrical signal and transmits it to the control unit.

[0012] As a further improvement of the present invention, the tension detection mechanism is a non-contact tension sensor or a contact tension sensor; the tension sensor is installed inside the guide roller or at a key node in the yarn path to capture the dynamic changes in yarn tension in real time.

[0013] As a further improvement of the present invention, the torque motor is a DC torque motor used to drive the guide mechanism to rotate. It can output large torque at low speed and has a response time of ≤10 milliseconds to achieve rapid tracking and compensation of yarn tension changes.

[0014] As a further improvement of the present invention, the guide roller is mounted on the fixed shaft by two bearings, thereby realizing the relative rotation between the guide roller and the fixed shaft; and the guide roller meshes with the transmission gear of the torque motor by means of the boss gear mounted thereon, forming a transmission connection.

[0015] As a further improvement of the present invention, the spring buffer mechanism further includes a bearing disposed between the connecting block and the fixed shaft of the guide roller; the bearing allows the guide roller to rotate freely for warp feeding, while transmitting the radial thrust generated by the guide roller under the action of yarn tension to the connecting block, thereby triggering the linear movement of the entire spring buffer mechanism.

[0016] As a further improvement of the present invention, the motor-driven constant tension yarn feeding device based on sensor feedback also includes a warp frame; multiple feeding units are arranged vertically on the warp frame, and the warp frames are arranged side by side to form a multi-channel independent feeding system, each channel can independently control the constant tension of a single yarn or a single layer of yarn.

[0017] Secondly, embodiments of the present invention provide a constant tension yarn feeding method, employing the aforementioned feeding device, which includes the following steps: S1, a predetermined number of warp feeding units are modularly installed on the warp frame according to a predetermined arrangement structure, and the warp frames are then arranged side by side to form a multi-channel independent warp feeding system; S2, the yarn passes through multiple guide rollers of each warp feed unit in a preset path, and the torque motor provides the initial warp feed power; S3, the tension detection mechanism detects the yarn tension in real time and transmits the signal to the control unit; S4, the control unit compares the collected real-time tension with the preset tension value. If the real-time tension is less than the preset tension value, it controls the torque motor to rotate in the opposite direction to tighten the yarn; if the real-time tension is greater than the preset value, it controls the torque motor to increase its speed or output torque to loosen the yarn. S5, when the yarn experiences a momentary tension peak, the spring buffer mechanism acts quickly to absorb the impact through elastic deformation and prevent the yarn from breaking.

[0018] Beneficial effects: This invention provides a sensor-feedback-based motor-driven constant tension warp feeding device, constructing a mechatronic "torque motor-tension sensor-spring buffer" triple-coordinated active-passive control warp feeding system. It is specifically designed to address the extremely stringent requirements for constant warp tension in the weaving of high-performance fibers (such as carbon fiber) and thick, multi-layered fabrics. It is not merely an improvement on a single component, but rather an intelligent control system for high-precision, high-response, and shock-resistant yarn tension through the organic combination of real-time closed-loop control and instantaneous passive buffering. Firstly, a real-time closed-loop active control loop of "torque motor-tension sensor" is designed. The tension detection mechanism monitors the yarn tension in real time and feeds the signal back to the control unit. The control unit dynamically and precisely adjusts the output torque of the torque motor (when the tension is low, the motor reverses to wind up; when the tension is high, the motor winds forward to loosen the warp), achieving active adjustment of the yarn tension and fundamentally overcoming the shortcomings of slow response and low precision in traditional mechanical mechanisms. Secondly, it integrates a "spring buffer mechanism" as a passive safety system. This passive buffering system utilizes guide rollers that can move along a slide rail and an elastic device. When the loom starts, stops, or inserts weft threads, causing instantaneous tension spikes, the spring buffer mechanism quickly absorbs the impact energy and releases the instantaneous tension through the displacement of the guide rollers, effectively preventing the high-performance fibers with high rigidity and low breaking elongation from breaking due to stress concentration. Most importantly, it achieves coordinated operation of active control and passive buffering. The torque motor handles relatively slow but continuous tension fluctuations, while the spring buffer mechanism is specifically designed to handle high-frequency, transient tension impacts. Together, they ensure that yarn tension remains stable within a very small fluctuation range throughout the entire weaving process, especially in complex conditions such as high-thickness, multi-layer weaving. It possesses the following technical advantages: 1. Precise real-time adjustment: The tension sensor can capture the instantaneous changes in yarn force with extremely high response speed. The control system can quickly analyze and process the changes, so that the yarn maintains a stable tension throughout the entire warping process.

[0019] 2. Improved Stability and Reliability: A real-time closed-loop control system is constructed using a torque motor and a high-precision tension sensor. The sensor dynamically captures the yarn stress signal and instantly feeds it back to the control unit, driving the torque motor to precisely adjust the output torque, ensuring that the yarn tension remains stable within a very small fluctuation range. At the same time, an innovative integrated spring buffer mechanism is used to absorb the instantaneous tension impact of the yarn during weaving by utilizing the elastic deformation characteristics of the spring, achieving dynamic tension compensation and constant control, effectively avoiding the risk of yarn breakage caused by stress concentration, and further improving the long-term stability and operational reliability of the warp feeding process.

[0020] 3. Energy Saving and High Efficiency: The torque motor dynamically matches the output torque based on real-time yarn force feedback, achieving energy saving through on-demand power supply and significantly reducing equipment operating costs. Simultaneously, relying on the high-speed collaborative response mechanism of the torque motor and sensors, the mechanism can instantly capture and accurately compensate for sudden changes in yarn force, greatly reducing problems such as yarn breakage and defects caused by abnormal yarn tension. This effectively reduces downtime and production interruption time, significantly improving weaving continuity and production efficiency. Furthermore, the innovative integrated tension visualization and digital monitoring module converts yarn tension data into digital signals in real time, presenting them intuitively on the control terminal. This facilitates the adjustment of the required tension, further enhancing the controllability and intelligence of the weaving process.

[0021] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0022] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the present invention will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0023] Figure 1 A schematic diagram of the overall structure of the motor-driven constant tension yarn feeding device based on sensor feedback provided in an embodiment of the present invention (showing a multi-unit modular arrangement structure).

[0024] Figure 2 A partial structural diagram of the warp feeding unit of the motor-driven constant tension yarn feeding device based on sensor feedback provided in an embodiment of the present invention (showing the relationship between the motor, roller, sensor and transmission).

[0025] Figure 3 A schematic diagram of the spring buffer mechanism of a motor-driven yarn constant tension feeding device based on sensor feedback provided in an embodiment of the present invention (showing the shrinkage mechanism of the guide roller under tension impact).

[0026] Figure 4 A detailed schematic diagram of the spring buffer mechanism of the motor-driven constant tension yarn feeding device based on sensor feedback provided in an embodiment of the present invention.

[0027] Figure 5 A schematic diagram of the guide roller assembly of a motor-driven constant tension yarn feeding device based on sensor feedback provided in an embodiment of the present invention (showing bearings, gears and transmission structure).

[0028] Figure 6 This is a schematic diagram of the assembly of the guide mechanism and spring buffer mechanism of the motor-driven yarn constant tension feeding device based on sensor feedback, provided in an embodiment of the present invention.

[0029] Figure 7 This is a schematic diagram of the warp winding path and tension transmission direction of the guide roller of the motor-driven constant tension yarn feeding device based on sensor feedback, provided in an embodiment of the present invention.

[0030] Figure 8 A schematic diagram of the force direction of the guide rollers of a motor-driven constant tension yarn feeding device based on sensor feedback provided in an embodiment of the present invention (indicating the direction of action of yarn tension F on each roller).

[0031] Explanation of reference numerals in the attached figures: 1. Yarn winding mechanism; 2. Guiding mechanism; 3. Spring buffer mechanism; 11. Screw; 12. Washer; 13. Snap ring; 14. Upper bearing; 15. Fixed shaft; 16. Lower bearing; 17. First guide roller; 18. Boss gear; 19. Torque motor; 21. Second guide roller; 22. Third guide roller (with sensor connection); 23. Fourth guide roller; 24. Fifth guide roller; 31. Bearing; 32. Connecting block; 33. Slide rail; 34. Elastic device. Detailed Implementation

[0032] The embodiments of the technical solution of the present invention will now be described in detail with reference to the accompanying drawings. These embodiments are merely illustrative of the technical solution of the present invention and are therefore intended to limit the scope of protection of the present invention.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the invention, are intended to cover non-exclusive inclusion.

[0034] In the description of the embodiments of this invention, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this invention, "multiple" means two or more, unless otherwise explicitly defined.

[0035] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0036] In the description of the embodiments of this invention, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0037] In the description of the embodiments of the present invention, the term "multiple" refers to two or more (including two), similarly, "multiple groups" refers to two or more (including two groups), and "multiple pieces" refers to two or more (including two pieces).

[0038] In the description of the embodiments of the present invention, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of the present invention.

[0039] In the description of the embodiments of the present invention, unless otherwise explicitly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention according to the specific circumstances.

[0040] To address the technical problems of inaccurate tension control and sluggish response in current warp feeding devices, which are unable to meet the stringent requirements of constant tension in high-performance fiber multilayer weaving, leading to high yarn breakage rates, uneven fabrics, and difficulties in independently controlling warp feeding, this invention provides a motor-driven constant tension warp feeding device based on sensor feedback. It constructs a three-in-one collaborative warp feeding system consisting of a torque motor, a high-precision tension sensor, and a spring buffer mechanism. Non-contact tension sensors mounted on staggered guide rollers capture yarn tension signals in real time. The control unit drives the torque motor to dynamically adjust the output force, forming a closed-loop control. A vertically movable spring buffer mechanism absorbs instantaneous tension impacts during start-up, shutdown, and weaving. Simultaneously, a multi-axis independent control design achieves precise warp feeding and constant tension for single warp yarns / layers, adapting to different yarn specifications and multilayer, high-thickness fabric weaving. This effectively avoids yarn stretching damage, breakage, and uneven fabric density, improving production efficiency and product qualification rate. It is particularly suitable for weaving high-performance inorganic fibers such as carbon fiber and glass fiber, which are extremely sensitive to tension, and can effectively meet the industrial production requirements of high-thickness, complex three-dimensional fabrics with 30 or even 50 layers or more.

[0041] Example 1 Please refer to Figures 1 to 8 As shown, the present invention provides a motor-driven constant tension yarn feeding device based on sensor feedback, including a control unit and a number of modularly arranged feeding units with independently configured feeding channels.

[0042] The delivery unit includes: The yarn winding mechanism 1 is composed of a torque motor 19 and a guide roller. The torque motor 19 is controlled by the control unit and is used to drive the guide mechanism 2 to rotate, thereby providing power for conveying the yarn. The guiding mechanism 2 includes multiple guide rollers, and the yarn passes around each guide roller in sequence to form a tension detection and buffering path; The tension detection mechanism is located at the tail of the guide roller and is used to detect the yarn tension in real time and generate a signal to be fed back to the control unit. Spring buffer mechanism 3 is connected to and cooperates with the guide roller, and is used to absorb the impact through its own deformation when the yarn tension increases instantaneously; The control unit receives a signal from the tension detection mechanism and compares it with a preset tension value. Based on the comparison result, it dynamically adjusts the output torque or rotation direction of the torque motor 19 to maintain constant yarn tension, thus forming a closed-loop tension control.

[0043] Please see Figures 5 to 8As shown, the guide mechanism 2 is a composite structure with a fixed shaft 15 as its core, bearings supporting the rotation of the roller, integrated sensors, and power reception via a boss gear 18. Its ingenious combination with the spring buffer mechanism 3 through bearings, sliding, and elastic connections perfectly integrates the three major functions of rotary warp feeding, linear buffering, and tension detection into a compact unit, achieving a highly integrated and functionally specialized design.

[0044] The core rotating component of the guiding mechanism 2 is a bearing-supported guide roller. Specifically, the guiding mechanism includes multiple guide rollers (first guide roller 17, second guide roller 21, third guide roller 22, fourth guide roller 23, and fifth guide roller 24). Each guide roller is precisely mounted on a fixed shaft 15 through the cooperation of an upper bearing 14 and a lower bearing 16, ensuring that the guide roller can rotate extremely smoothly relative to the fixed shaft 15, minimizing the feeding resistance and avoiding wear on the high-performance fibers.

[0045] Furthermore, multiple guide rollers are arranged in a staggered, vertical configuration, with the yarn meandering along an "S"-shaped path. This increases the yarn wrap angle, ensuring reliable transmission. This arrangement ensures that the yarn exerts opposite forces on adjacent guide rollers. When the instantaneous tension is too high, the upper guide rollers (first guide roller 17, second guide roller 21, and third guide roller 22) are pressed down, while the lower guide rollers (fourth guide roller 23 and fifth guide roller 24) are lifted. They simultaneously contract inward, effectively and efficiently releasing the peak tension on a section of the yarn. Figure 8 It illustrates the winding path of the yarn and the direction of force, and explains how multiple guide rollers achieve synergistic buffering through relative motion under tension impact.

[0046] The power input interface of the guide mechanism 2 is a boss gear 18. In some specific embodiments, at least one guide roller is connected to the boss gear 18. The protrusion on the boss gear 18 engages with the groove on the end face of the guide roller to achieve circumferential rigid linkage. This allows the power of the torque motor 19 to be transmitted to the guide roller without slippage through the gear pair, achieving active yarn feeding rather than passive dragging.

[0047] In the guiding mechanism 2, the tail of the guide roller 22 is connected to a sensor. The pressure generated when the yarn passes over the guide roller is detected in real time and a signal is output, which serves as the direct basis for the control unit to sense the yarn tension.

[0048] The guide mechanism 2 and the spring buffer mechanism 3 cooperate to form a sliding whole. The entire component consisting of "guide roller-fixed shaft 15-connecting block 32" is a movable rigid whole, which is the basis for realizing the buffer function.

[0049] Please see Figures 3 to 4As shown, the spring buffer mechanism 3 is a modular linear motion structure consisting of a guide rail 33, a connecting block 32 for force transmission, and an elastic device 34. It converts the radial force from the rotating guide roller into precise linear motion and efficiently transmits it to the elastic device 34. This design ensures the spring buffer mechanism 3's rapid and reliable response to instantaneous tension impacts and its automatic reset, making it a core technological means to ensure the safety of high-performance fibers under harsh weaving conditions.

[0050] The spring buffer mechanism 3 is not an isolated spring, but an independent module composed of multiple precision components, with clear guiding and reset functions.

[0051] In some specific embodiments, the elastic device 34 is specifically a cylindrical compression spring. It is made of 304 stainless steel, possessing stable mechanical properties and rust resistance. Its key design parameters include: wire diameter 1mm, spring mean diameter 10mm, free length 50mm, and elastic modulus 2N / mm. These parameters determine its buffering capacity and stroke range. The other end of the elastic device 34 is fixed to the frame, providing a reaction force basis for the deformation of the compression spring.

[0052] The core function of the slide rail 33 is to provide precise linear guidance for the spring buffer mechanism 3 and the guide roller, ensuring that the buffering action is strictly performed in the preset direction, avoiding any jamming or deflection, and ensuring the reliability and consistency of the response.

[0053] The connecting block 32 is the core of force transmission and structural hub of the entire spring buffer mechanism 3. One end of it is connected to the fixed shaft 15 of the guide roller via a bearing 31, and the other end is fastened to the sliding component on the slide rail 33 via screws. It is also directly connected to the elastic device 34 (which can be fastened by welding). Therefore, the connecting block 32 acts as a link between the two, converting the tension of the yarn into the linear motion of the spring buffer mechanism, which directly acts on the compression spring.

[0054] A bearing 31 is provided between the connecting block 32 and the fixed shaft 15 of the guide roller. The bearing 31 allows the guide roller to rotate freely for warp feeding, while simultaneously transmitting the radial thrust generated by the guide roller under tension to the connecting block 32 without loss, thereby triggering the linear movement of the entire spring buffer mechanism. The guide roller and the spring buffer mechanism 3 establish a "motion-decoupled force transmission" relationship through the lower bearing 16 and bearing 31. The lower bearing 16 ensures the independent rotational function of the guide roller, while bearing 31 acts as a precise force conversion interface, efficiently and without loss transmitting the axial force borne by the rotating component to the linearly moving spring buffer mechanism 3, while allowing relative rotation between the two. This design is the mechanical basis for the device to simultaneously achieve the two key functions of smooth warp feeding and instantaneous buffering.

[0055] The above-described structure and connection method of the spring buffer mechanism 3 together realize its core function: During tension impact: the yarn tension increases suddenly → acting on the guide roller → the thrust is transmitted through the fixed shaft 15 of the guide roller → pushing the connecting block 32 to move along the slide rail 33 → compressing the elastic device 34 (compressing the spring) → the elastic device 34 deforms and absorbs the impact energy.

[0056] When the tension is restored: After the instantaneous tension has passed, the compressed elastic device 34 releases its elastic potential energy, pushing the connecting block 32 to move in the opposite direction along the slide rail 33, driving the entire guide roller to accurately return to its initial position, completing one buffer cycle.

[0057] After the tension is released, the guide roller is returned to its original position by the compression spring. The guide roller passes through the bearing 31 and is locked in the groove, restricting its displacement only in the vertical direction (e.g., ...). Figure 4 In order to maintain stable operation, the guide roller needs to have a reasonable weight so that the fixed shaft 15 of the guide roller can be reset by its own weight without the yarn breaking due to excessive weight.

[0058] When the yarn passes through the guide mechanism 2 in the warp feeding unit, the torque motor 19 is in an initial working state, providing basic conveying power for the yarn. The five guide rollers are arranged in a staggered pattern, and the yarn is given the same tension F as it passes through them (e.g., ...). Figure 8 As shown in the figure, the pressure sensor inside the guide roller detects the stress on the yarn in real time during the initial conveying process.

[0059] When the yarn is subjected to different traction forces or when the force changes due to uneven yarn quality, the tension detection mechanism can quickly capture these changes and transmit the signals to the control unit rapidly and accurately so that the control unit can respond in a timely manner.

[0060] During normal weaving, when the tension detection mechanism detects that the yarn tension is less than the preset standard value, the control unit will control the torque motor 19 to rotate in the opposite direction to tighten the yarn, so that the yarn is subjected to greater tension and thus becomes taut; conversely, when the tension is detected to be too high, the control unit will instruct the torque motor 19 to reduce the output torque and feed the warp in time to reduce the yarn tension.

[0061] During the warp feeding process, the tension detection mechanism monitors the changes in yarn tension in real time and transmits the data to the control unit, providing accurate data for the adjustment of the torque motor 19, thereby achieving precise control of the yarn tension.

[0062] To address the excessive instantaneous tension within the yarn caused by the start-stop moment of the guide mechanism 2, the spring buffer mechanism 3 (such as...) Figure 3As shown, the guide rollers retract inwards at the moment of start-up and stop.

[0063] During warp feeding, the torque motor 19 can output high torque at low speeds, making it suitable for adjusting yarn tension during warp feeding. Furthermore, during yarn winding, the torque motor 19 can provide a constant torque to maintain internal yarn tension for different numbers of high-performance fibers. Moreover, the torque motor 19 has strong overload capacity and fast response speed, capable of withstanding a certain degree of overload and adjusting its output torque in a timely manner to adapt to changes in yarn stress, truly achieving digital control of yarn tension.

[0064] In one feasible implementation, all warp yarns drawn from each bobbin are arranged approximately horizontally in the guide section of the warp guide bar. Therefore, the motor selection depends on: The warp yarn arrangement density on each yarn bobbin is 20-25 yarns / cm; The effective winding length of the yarn bobbin is 20cm, and the diameter is 6cm; One layer of fabric contains 25 × 20 = 500 fibers; The actual measured force on a single bundle of yarn is 0.5N; There is a set of minimum output torques required to control the motor: 500×0.5×3×10-2=7.5Nm.

[0065] Final working status (e.g.) Figure 1 The warp feeding method is active warp feeding. The torque motor 19 works in conjunction with the tension detection mechanism to achieve constant tension of high warp density warp yarns and independent conveying them according to a specific arrangement and direction.

[0066] The specific structural parameters of the warp feeding device are as follows: Torque motor 19: A DC torque motor (model: LYJ-100) is used, with a rated voltage of 220V, a rated speed of 50r / min, a torque adjustment range of 0.1~10N・m, and a response time of ≤10ms.

[0067] Tension detection mechanism (tension sensor): High-precision strain gauge pressure sensor (model: YZC-526) is selected, with a measurement range of 0~50N and a non-contact detection method (the contact pressure between the yarn and the sensor is ≤0.1N).

[0068] Spring buffer mechanism 3: It adopts a cylindrical compression spring, made of stainless steel 304, with a wire diameter of 1mm, a spring mean diameter of 10mm, a free length of 50mm, a working stroke of 10~30mm, an elastic coefficient of 2N / mm, and a maximum compression of 40mm. It is installed between the sensor and the guide slider.

[0069] Guide roller: Made of aluminum alloy, 60mm in diameter, weighing ≤2kg; the transmission mechanism is directly driven by torque motor 19 and gear transmission.

[0070] The overall length of the feeding device is 400mm, the width is 200mm, the height is 150mm, and the weight is ≤15kg. The spring buffer mechanism is tightly fitted with the guide roller, and the rapid rebound control unit is installed on the side of the device. The line connection length with the torque motor and tension sensor is ≤1.5m.

[0071] Example 2 Based on the sensor feedback-based motor-driven constant tension yarn feeding device provided in Embodiment 1, Embodiment 2 of the present invention also provides a constant tension yarn feeding method for weaving a 5-layer thin carbon fiber fabric. The yarn feeding process using this feeding device includes the following steps: S1, a predetermined number of warp feeding units are modularly installed on the warp frame according to a predetermined arrangement structure, and the warp frames are then arranged side by side to form a multi-channel independent warp feeding system; S2, the yarn passes through multiple guide rollers of each warp feed unit in a preset path, and the torque motor provides the initial warp feed power; S3, the tension detection mechanism detects the yarn tension in real time and transmits the signal to the control unit; S4, the control unit compares the collected real-time tension with the preset tension value. If the real-time tension is less than the preset tension value, it controls the torque motor to rotate in the opposite direction to tighten the yarn; if the real-time tension is greater than the preset value, it controls the torque motor to increase its speed or output torque to loosen the yarn. S5, when the yarn experiences a momentary tension peak, the spring buffer mechanism acts quickly to absorb the impact through elastic deformation and prevent the yarn from breaking.

[0072] The specific equipment configuration is as follows: Five sets of the warp feeding unit from Example 1 above were used, employing T300 carbon fiber yarn with a linear density of 1500D, a single filament diameter of 7μm, a breaking strength of 3.5GPa, and a breaking elongation of 1.8%. Each layer contained 500 warp yarns, for a total of 2500 warp yarns. The warp yarn width was 20mm, and the warp yarn arrangement density was 20-25 yarns / cm. The weaving length was 50m. The theoretical yarn consumption was calculated as (total warp yarns × width × weaving length × linear density) / (1000 × 1000) = (2500 × 20 × 50 × 1500) / 10^8 = 37.5kg. The actual yarn consumption, considering losses (loss rate ≤ 2%), was 38.3kg.

[0073] The specific weaving process is as follows: Five warp feed units are installed on the warp frame. The warp yarns pass sequentially through the guide rollers, tension detection mechanism, and guide rollers into the heald frame of the loom, and finally enter the reed. After the loom starts, the tension detection mechanism collects the warp tension data and transmits it to the control unit, which in turn drives the torque motor 19 to adjust the output torque in real time. When the yarn tension decreases due to a reduction in yarn size, the torque motor 19 reverses to tighten the yarn, and vice versa, it continues to rotate to increase the warp feed. At the moment of start-up and shutdown, the spring buffer mechanism 3 simultaneously absorbs the instantaneous tension peak to avoid stress concentration.

[0074] Example 3 Embodiment 3 of the present invention also provides a constant tension warp feeding method for weaving 50-layer high-thickness carbon fiber fabric. The warp feeding process using this warp feeding device includes the following steps: S1, a predetermined number of warp feeding units are modularly installed on the warp frame according to a predetermined arrangement structure, and the warp frames are then arranged side by side to form a multi-channel independent warp feeding system; S2, the yarn passes through multiple guide rollers of each warp feed unit in a preset path, and the torque motor provides the initial warp feed power; S3, the tension detection mechanism detects the yarn tension in real time and transmits the signal to the control unit; S4, the control unit compares the collected real-time tension with the preset tension value. If the real-time tension is less than the preset tension value, it controls the torque motor to rotate in the opposite direction to tighten the yarn; if the real-time tension is greater than the preset value, it controls the torque motor to increase its speed or output torque to loosen the yarn. S5, when the yarn experiences a momentary tension peak, the spring buffer mechanism acts quickly to absorb the impact through elastic deformation and prevent the yarn from breaking.

[0075] The specific equipment configuration is as follows: 50 units of the above-described embodiment 1 (e.g., ...) are used. Figure 1 The total area is approximately 50m² (10m long × 5m wide). T700 carbon fiber yarn is used, with a linear density of 3000D, a single filament diameter of 7μm, a breaking strength of 4.9GPa, and a breaking elongation of 2.1%. Each layer has 500 warp yarns, for a total of 25,000 warp yarns. The warp width is 20mm, and the warp yarn density is 20-25 yarns / cm. The weaving length is 50m. The theoretical yarn consumption is (25000 × 20 × 50 × 3000) / 10^8 = 750kg. The actual yarn consumption, considering losses (loss rate ≤ 3%), is 773.2kg.

[0076] Motor control parameters: The torque motor 19 operates at a speed of 80~250 r / min, with an output torque of 1.0~3.5 N·m and a warp feed speed of 30~80 m / min. It adopts a multi-axis synchronous control strategy, with a speed deviation of ≤1 r / min for 50 motors and a torque adjustment synchronization of ≤5 ms.

[0077] Fifty warp feed units are installed in 10 groups on the warp frame, with five units in each group and a spacing of 300mm between adjacent units. The yarn path adopts a layered guide design, with each layer of warp yarn passing through the corresponding guide wheel independently to avoid interlayer entanglement.

[0078] After the loom starts, the tension sensor collects warp tension data in real time, and the corresponding torque motor 19 can dynamically adjust the rotation direction and output torque; the spring buffer mechanism 3 absorbs the tension impact caused by weft yarn interlacing or warp winding changes, preventing yarn stress concentration and breakage.

[0079] In summary, this invention provides a sensor-feedback-based motor-driven constant tension warp feeding device, belonging to the field of textile machinery technology. This invention aims to solve the problems of yarn damage, yarn breakage, and fabric defects caused by imprecise tension control during the weaving of high-performance fibers in thick, multi-layered fabrics. It constructs an intelligent system with dual collaboration between "active motor closed-loop control" and "passive mechanical instantaneous buffering": this system monitors yarn tension in real time through a tension sensor integrated in the guide rollers and feeds the signal back to the control unit, thereby dynamically adjusting the output torque of the torque motor to achieve precise and rapid closed-loop control of tension; simultaneously, the unique spring buffering mechanism allows the key guide rollers to move on the slide rail, effectively absorbing instantaneous tension spikes generated during loom start-up, weft insertion, etc., protecting the fibers. Through mechatronics integration design, this invention achieves high-precision constant control of warp feeding tension, significantly improving weaving quality, efficiency, and reliability, and is particularly suitable for the industrial production of multi-layered complex fabrics made of high-performance fibers such as carbon fiber, which are extremely sensitive to tension fluctuations.

[0080] It should be noted that the present invention is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments that have the same structure and perform the same effects as the technical concept within the scope of the present invention are included within the scope of the present invention. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of the present invention, are also included within the scope of the present invention.

Claims

1. A motor-driven constant tension yarn feeding device based on sensor feedback, characterized in that, It includes a control unit and modularly arranged, independently configured warp-feeding units; the warp-feeding unit includes: The guiding mechanism includes multiple guide rollers, and the yarn passes around each guide roller in sequence to form a tension detection and buffering path; A torque motor, controlled by the control unit, is used to drive the guide mechanism to rotate, providing conveying power for the yarn; The tension detection mechanism is located at the tail of the guide roller and is used to detect the yarn tension in real time and generate a signal to be fed back to the control unit. The spring buffer mechanism is connected to and moves in coordination with the guide roller, and is used to absorb the impact through its own deformation when the yarn tension increases instantaneously; The control unit receives signals from the tension detection mechanism and compares them with a preset tension value. Based on the comparison result, it dynamically adjusts the output torque or rotation direction of the torque motor to maintain constant yarn tension, thus forming a closed-loop tension control.

2. The motor-driven constant tension yarn feeding device based on sensor feedback according to claim 1, characterized in that, The spring buffer mechanism includes: Slide rails provide a directional sliding path; The connecting block has one end connected to the shaft of the guide roller via a bearing, and the other end slidably engaged with the slide rail; An elastic device, connected to the connecting block, provides a restoring elastic force to the guide roller; When the instantaneous tension of the yarn exceeds the preset tension value, the guide roller compresses or stretches the elastic device and moves along the slide rail to release the tension.

3. The motor-driven constant tension yarn feeding device based on sensor feedback according to claim 2, characterized in that, The guide roller is mounted on a fixed shaft via two bearings to achieve relative rotation with the fixed shaft; and the guide roller meshes with the transmission gear of the torque motor via a boss gear mounted on it to form a transmission connection.

4. The motor-driven constant tension yarn feeding device based on sensor feedback according to claim 3, characterized in that, The spring buffer mechanism also includes a bearing disposed between the connecting block and the fixed shaft of the guide roller; the bearing allows the guide roller to rotate freely for warp feeding, while transmitting the radial thrust generated by the guide roller under tension to the connecting block, thereby triggering the linear movement of the entire spring buffer mechanism.

5. The motor-driven constant tension yarn feeding device based on sensor feedback according to claim 2, characterized in that, Multiple guide rollers are arranged in an alternating pattern to form an S-shaped winding path, so that the force exerted by the yarn on the guide rollers is opposite in direction when the yarn winds around. When the instantaneous tension of the yarn is too high, the upper guide roller moves downward while the lower guide roller moves upward, working together to quickly release the peak tension in the yarn.

6. The motor-driven constant tension yarn feeding device based on sensor feedback according to claim 1, characterized in that, The control unit adopts a multi-axis synchronous control strategy to simultaneously control the torque motors of multiple warp feeding units.

7. The motor-driven constant tension yarn feeding device based on sensor feedback according to claim 1, characterized in that, The tension detection mechanism is a high-precision pressure sensor integrated inside the guide roller; the pressure sensor converts the pressure signal of the yarn on the guide roller into an electrical signal and transmits it to the control unit.

8. The motor-driven constant tension yarn feeding device based on sensor feedback according to claim 1, characterized in that, The torque motor is a DC torque motor, which can output large torque at low speed and has a response time of ≤10 milliseconds to achieve rapid tracking and compensation of yarn tension changes.

9. A motor-driven constant tension yarn feeding device based on sensor feedback according to claim 1, characterized in that, The sensor-feedback-based motor-driven constant tension yarn feeding device also includes a warp frame; multiple feeding units are arranged vertically on the warp frame, and the warp frames are arranged side by side to form a multi-channel independent feeding system, each channel can independently control the constant tension of a single yarn or a single layer of yarn.

10. A method for constant tension yarn feeding, employing the yarn feeding device as described in any one of claims 1 to 9, characterized in that, Includes the following steps: S1, a predetermined number of warp feeding units are modularly installed on the warp frame according to a predetermined arrangement structure, and the warp frames are then arranged side by side to form a multi-channel independent warp feeding system; S2, the yarn passes through multiple guide rollers of each warp feed unit in a preset path, and the torque motor provides the initial warp feed power; S3, the tension detection mechanism detects the yarn tension in real time and transmits the signal to the control unit; S4, the control unit compares the collected real-time tension with the preset tension value. If the real-time tension is less than the preset tension value, it controls the torque motor to rotate in the opposite direction to tighten the yarn; if the real-time tension is greater than the preset value, it controls the torque motor to increase its speed or output torque to loosen the yarn. S5, when the yarn experiences a momentary tension peak, the spring buffer mechanism acts quickly to absorb the impact through elastic deformation and prevent the yarn from breaking.

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