A multi-mode coordinated warp feeding weaving method

Abstract

The application discloses a multi-mode coordinated warp feeding weaving method and belongs to the technical field of textile weaving. In view of the technical prejudice that the same fabric must adopt the same warp feeding mode in the prior art, the application breaks through the rule and divides all warp yarns into at least two groups, the first group of warp yarns adopts tension induction type passive warp feeding, and the second group of warp yarns adopts clamping type fixed-length warp feeding. Through the coordinated cooperation of the two warp feeding modes, the warp feeding amount difference of the two groups of warp yarns is utilized, so that the fabric can produce controllable shrinkage deformation after weaving. The application creatively transforms the "warp feeding amount difference" which is traditionally regarded as a weaving defect into a "technical means" for realizing controllable shrinkage, and is particularly suitable for the weaving of high-elasticity yarn fabrics. By introducing a shrinkage coefficient λ, a mathematical relationship between the fixed-length warp feeding amount and the winding length is established, the accurate prediction and control of the shrinkage deformation of the elastic fabric are realized, and the technical problems of poor size stability and uncontrollable shrinkage of the elastic fabric are solved.

Description

Technical Field

[0001] This invention relates to the field of textile weaving technology, specifically a weaving method with multi-mode coordinated warp feeding. Background Technology

[0002] In the field of textile weaving, the warp feeding system is a key device that transports warp yarns from the warp beam to the weaving point at a certain speed and tension. For a long time, a deep-seated technical bias has existed in this field: all warp yarns of the same fabric must use the same warp feeding method. This technical bias stems from the following perceptions: (1) using the same warp feeding method can ensure the stability of the weaving process and avoid uneven tension and weaving failures caused by different warp feeding methods; (2) the structure of weaving equipment is simplified, making operation and maintenance easier; (3) the elastic properties of traditional fabrics (such as cotton, linen, and ordinary polyester) are small, and the same warp feeding method is sufficient to meet the process requirements. Based on the above technical bias, in traditional weaving, all warp yarns of the same fabric usually use the same warp feeding method, mainly including the following two: While tension warping is used throughout, there are technical problems with uncontrollable shrinkage of elastic yarns, making it difficult to control the shrinkage of elastic fabrics. For high-elasticity yarns (such as spandex core-spun yarn and high-elastic polyester), if tension warping is used throughout, the fabric will shrink severely after weaving, resulting in poor dimensional stability. If fixed-length warping is used, it is difficult to ensure the stability of tension during weaving, which can easily lead to defects.

[0003] Alternatively, fixed-length warp feeding can be used entirely, but this presents a technical challenge in ensuring consistent tension.

[0004] To address this, existing patent number CN202210844120.4 discloses a warp knitting variable speed uniform tension yarn feeding device, which actively adjusts the tension of a single group of warp yarns through a variable speed tension adjustment wheel to maintain uniform yarn feeding tension. This technical solution is designed for warp knitting processes and pursues tension uniformity, but it cannot effectively solve the shrinkage problem that occurs after high elastic yarns are unloaded, and therefore cannot achieve dimensional stability. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a weaving method with multi-mode coordinated warp feeding.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a weaving method with multi-mode coordinated warp feeding, comprising: in the same weaving process, at least two sets of warp yarns are provided, wherein the first set of warp yarns adopts tension-sensing passive warp feeding, and the second set of warp yarns adopts clamping-type fixed-length warp feeding, wherein the clamping-type fixed-length warp feeding controls the warp feeding length according to the weft density parameter, and the two sets of warp yarns converge at the weft insertion point to jointly form the fabric; wherein the coordinated weaving process includes the following steps: Each time a weft is introduced, the crimping mechanism crimps the length according to the weft density parameter; The tension warp feed unit adjusts the warp feed amount according to the warp tension; The fixed-length warp feeding group is actively fed by the clamping device according to a set length; The two sets of warp yarns meet at the weft bend to form the fabric.

[0007] As a preferred embodiment of this application, the first group of warp yarns and the second group of warp yarns are respectively composed of any one or a combination of high-elasticity yarn, conventional yarn, or other yarns.

[0008] As a preferred embodiment of this application, the warp feed length Ls of the clamping fixed-length warp feed is L×λ, where L is the curling length per weft of the curling mechanism and λ is the shrinkage coefficient. The shrinkage coefficient λ is determined based on the fabric's designed shrinkage rate ε: When the fabric is designed for longitudinal shrinkage, λ = 1 / (1+ε), and the value of ε ranges from 0.1 to 0.7. When the fabric is designed for longitudinal elongation, λ = 1 + δ, where δ ranges from 0.1 to 0.5. When the fabric is designed without longitudinal deformation, λ=1.

[0009] As a preferred embodiment of this application, the clamping fixed-length warp feed includes: after the fixed-length yarn is drawn out from the fixed-length yarn warp beam, it enters the fixed-length yarn warp feed beam, and a pressure mechanism applies controllable pressure to the fixed-length yarn warp feed beam, thereby driving the yarn forward through friction to achieve active warp feeding according to a set length.

[0010] As a preferred embodiment of this application, the clamping mechanism is a clamping shaft disposed on both sides of the warp feed shaft of the fixed-length yarn.

[0011] As a preferred embodiment of this application, the clamping mechanism includes a clamping drive device, which is one of pneumatic clamping, hydraulic clamping or mechanical spring clamping, and its power output end acts on the clamping shaft that abuts against it. The clamping shaft abuts against the warp feed shaft for the fixed-length yarn.

[0012] As a preferred embodiment of this application, yarn guide shafts are also provided on both the front and rear sides of the fixed-length yarn feed shaft to guide the fixed-length yarn to be fed to the weft insertion point along a predetermined path.

[0013] As a preferred embodiment of this application, the weaving method is applicable to the weaving of plain weave, twill weave, satin weave, and their variations. Compared with the prior art, the beneficial effects of the present invention are as follows: 1. It broke through the technical prejudice that "the same fabric must use the same warp feeding method" and pioneered a new technical route for multi-mode collaborative warp feeding.

[0014] 2. Precise control of shrinkage deformation of elastic fabrics is achieved: By coordinating tension warp feeding and fixed-length warp feeding, the fixed-length warp feeding amount is precisely controlled using the shrinkage coefficient λ, thereby controlling the final shrinkage rate of the fabric. The dimensional stability CV value is reduced from the traditional >8% to <3%.

[0015] 3. Ensures the stability of the weaving process: The tension feeding group automatically adjusts the tension to ensure a smooth weaving process and reduces the warp breakage rate by more than 60%; the fixed-length feeding group feeds the warp according to the set length to avoid excessive elongation of the elastic yarn, and the defect rate is reduced from the traditional 5% to 8% to <2%.

[0016] 4. Improved fabric dimensional stability: The fabric size is close to the design specifications after coming off the machine, reducing the cutting allowance in the finishing process and increasing the yield from the traditional 80% to 90% to >95%.

[0017] 5. Expanded the range of elastic fabrics: Applicable to yarns with different elastic properties. By adjusting the λ value and the ratio of the two sets of warp yarns, fabrics with different shrinkage rates and elasticity can be woven, increasing the added value of products by more than 30%.

[0018] 6. Reduced production costs: Reduced waste caused by size instability, improved weaving efficiency, and reduced overall production costs by 15% to 20%. Attached Figure Description

[0019] Other features, objects, and advantages of the invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the main structure of the present invention; Figure 2 This is a schematic diagram of another clamping mechanism structure in the present invention; In the diagram: 1. Tension-sensing passive warp feed; 2. Clamping-type fixed-length warp feed; 3. Fixed-length yarn warp beam; 4. Pressing mechanism; 41. Clamping shaft; 5. Fixed-length yarn warp feed beam; 6. Pressing shaft; 61. Pressing drive device; 8. Yarn guide shaft; 9. Shedding mechanism; 10. Beating-up mechanism; 11. Curling mechanism. Detailed Implementation

[0020] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0021] This application utilizes a weaving apparatus with multi-mode coordinated warp feeding to produce fabrics, the structure of which includes: A standard yarn warp beam is used to wind the first set of warp yarns; A tension sensing device, located at the rear beam, is used to detect the tension of the first set of warp yarns and provide feedback to adjust the warp feed amount. A fixed-length yarn warp beam is used to wind the second set of warp yarns; A fixed-length yarn feed beam is connected to a fixed-length yarn weaving beam and is used to feed the second set of warp yarns according to a set length. A pressing mechanism includes a pressing shaft and a pressing drive device. The pressing shaft abuts against a fixed-length yarn warp feed shaft and is used to apply controllable pressure to the fixed-length yarn warp feed shaft, thereby driving the yarn forward through friction. The yarn guide shaft is set on both sides of the fixed-length yarn feed shaft to guide the second set of warp yarns to be fed along a predetermined path. The sheathing mechanism is used to lift the two sets of warp yarns to different heights to form a shed. The beat-up mechanism is used to beat the introduced weft yarn toward the weft end, so that the two sets of warp yarns interweave with the weft yarn; A take-up mechanism for taking up fabric according to weft density parameters; The control unit is used to calculate the take-up length L and shrinkage coefficient λ based on the weft density parameter, and control the warp feed beam of the fixed-length yarn to feed the warp at the set length Ls = L × λ.

[0022] Among them, high-elasticity yarns include, but are not limited to, any one or a combination of spandex bare yarn, spandex core-spun yarn, spandex covered yarn, nylon high-elasticity yarn, high-elasticity polyester, PET / PTT bicomponent composite yarn, PTT polymer yarn, and high-elasticity acrylic yarn; Conventional yarns include, but are not limited to, natural fiber yarns: cotton yarn (carded / combed), linen yarn, wool yarn, and silk yarn; man-made fiber yarns: viscose yarn, modal yarn, Tencel yarn, and bamboo fiber yarn; and synthetic fiber yarns: any one or a combination of polyester staple fiber yarn, nylon filament (FDY / POY), and acrylic yarn.

[0023] Example 1: Spandex core-spun elastic fabric A weft-stretch fabric is woven, with conventional cotton yarn (first group) as warp yarns and spandex core-spun yarns as weft yarns. To control weft shrinkage, some weft yarns are changed to a warp configuration, i.e., two groups of warp yarns are used: Group 1 (Tension Warp Feeding Group): Conventional cotton yarn (linear density 18tex, breaking strength 18cN / tex, elastic recovery rate 8%, breaking elongation 7%), accounting for 70% of the total number of warp yarns, using tension-sensing passive warp feeding; The second group (fixed-length warp feeding group): spandex core-spun yarn, with a core of 20D polyurethane elastic fiber and an outer layer of 32S cotton yarn, core yarn content of 12%, linear density of 28tex, breaking strength of 12cN / tex, elastic recovery rate of 92%, and breaking elongation of 520%, accounting for 30% of the total number of warp yarns, and using clamping fixed-length warp feeding.

[0024] Fabric design parameters: Finished width: 150cm Finished weft density: 40 threads / cm On-machine weft density: 35 threads / cm (considering shrinkage after weft insertion) Shrinkage coefficient λ: 0.85 The fabric design shrinkage rate ε is 17.6%, calculated using λ=1 / (1+ε).

[0025] Weaving process: (1) For each weft introduced, the winding mechanism winds a certain length L according to the weft density parameter, L=100 / P=100 / 350≈0.286mm; (2) The tension feeding group (cotton yarn) automatically adjusts the feeding amount according to the warp tension, and the weaving tension is maintained in the range of 30 to 50 cN, with a tension fluctuation range of ±2 cN; (3) The fixed-length warp feed group (spandex core-spun yarn) is actively fed by the clamping device according to the set length. The warp feed length = L×λ = 0.286×0.85≈0.243mm; (4) The two sets of warp yarns meet at the weft beating line to form the fabric together. The weft beating force is 400N and the weft beating frequency is 600 times / min. (5) After the fabric is off the machine, it is left to stand in a relaxed state for 24 hours. The ambient temperature is 25℃ and the relative humidity is 65%. The spandex core-spun yarn shrinks back, and the fabric width shrinks from 180cm on the machine to 150cm. The longitudinal shrinkage rate is 16.7%, which is close to the design shrinkage rate of 17.6%. The size deviation is <5%, and the size stability CV value is 2.6%.

[0026] Comparative experimental data: As can be seen from the table above, the proposed solution is significantly superior to the single warp feeding method in terms of shrinkage controllability, dimensional stability, weaving stability, and yield.

[0027] Example 2: High-elastic polyester sports fabric Weave a high-elastic polyester fabric for sportswear: Group 1 (Tension Warp Group): High-elastic polyester filament (low-elasticity zone), accounting for 60% of the total warp yarns, with an elastic recovery rate of 15% and a breaking elongation of 25%; The second group (fixed-length warp feeding group): high-elastic polyester filament (high-elastic zone), accounting for 40% of the total number of warp yarns, with an elastic recovery rate of 88% and a breaking elongation of 480%.

[0028] Fabric design parameters: Finished product density: 50 threads / cm Machine density: 42 threads / cm Shrinkage coefficient λ: 1.15 Fabric design elongation: 13.0%, calculated using λ=1 / (1+ε), ε=-0.13. Weaving process: The warp feed length of the fixed-length warp feed group is L × 1.15. After exiting the machine, the high-elasticity zone shrinks back, forming longitudinal wrinkles on the fabric surface, giving the fabric a special appearance and three-dimensional elasticity. The measured longitudinal elongation is 12.5%, which deviates from the design value of 13.0% by less than 4%.

[0029] Comparative experimental data: This application's solution achieves a special fabric effect that traditional methods cannot obtain through a design with λ>1.

[0030] Example 3: Plain weave stretch denim Weave a type of stretch denim: Group 1 (Tension Warp Feeding Group): Cotton yarn, accounting for 80% of the total number of warp yarns; The second group (fixed-length warp yarn group): spandex core-spun yarn (core yarn content 12%, linear density 18tex), accounting for 20% of the total number of warp yarns.

[0031] Fabric design parameters: Finished weft density: 30 threads / cm Weft density: 26 threads / cm Shrinkage coefficient λ: 0.75 Fabric design shrinkage rate: 33.3% Weaving process: The warp feed length of the fixed-length warp feeder is L×0.75. After the warp is removed from the machine, the spandex core-spun yarn shrinks back, and the fabric undergoes a longitudinal shrinkage of about 30%, giving the denim a comfortable elasticity while maintaining the classic denim look.

[0032] Comparative experimental data: Example 4: Twill elastic fabric Weave a 2 / 1 twill elastic fabric: Group 1 (Tension Warp Threading Group): Polyester-cotton blended yarn (T / C 65 / 35), accounting for 65% of the total warp yarns; The second group (fixed-length warp yarn group): spandex core-spun yarn, accounting for 35% of the total number of warp yarns.

[0033] Fabric design parameters: Finished weft density: 45 threads / cm Weft density on the machine: 40 threads / cm Shrinkage coefficient λ: 0.90 Fabric design shrinkage rate: 11.1% Weaving process: The fabric uses a twill weave, with fixed-length warp feed groups configured in specific reed teeth (two spandex core-spun yarns are configured for every three polyester-cotton yarns). After the fabric leaves the machine, the spandex core-spun yarns shrink back, causing the fabric to shrink controllably in the twill weave direction, thus enhancing the fabric's three-dimensionality and elasticity.

[0034] Key process parameters: Opening height: 50mm Opening time: 300° Latitude adjustment time: 100° Weft strength: 500N Winding speed: 2m / min Winding tension: 200cN After being removed from the machine, the fabric was left to stand for 36 hours at 25℃ and 65%RH. The longitudinal shrinkage rate was 10.5%, which is less than 5% of the design value of 11.1%. The twill pattern is clear and three-dimensional, and the hand feel is full.

[0035] Example 5: Coordinated weaving of multiple warp yarns To weave a composite fabric with multiple elasticities, all warp yarns are divided into three groups: Group 1 (Tension Warp Feeding Group): Cotton yarn, accounting for 50% of the total number of warp yarns; Group 2 (fixed-length warp feeding group A): spandex core-spun yarn, accounting for 25% of the total number of warp yarns, λ1=0.80; Group 3 (Fixed-length warp feeding group B): High-elastic polyester, accounting for 25% of the total number of warp yarns, λ2=1.10.

[0036] Weaving process: The second group produces a shrinkage effect (designed shrinkage rate of 25%), and the third group produces an elongation effect (designed elongation rate of 10%). The two groups work together to form a complex elastic distribution in the fabric: the middle area shrinks and the sides elongate, which is suitable for three-dimensional tailoring of functional sportswear.

[0037] This embodiment demonstrates the scalability of the method of this application: by configuring different λ values ​​of multiple sets of warp yarns, it is possible to achieve complex elastic distribution and three-dimensional shaping effects that cannot be obtained by the traditional single warp feeding method.

[0038] Example 6: Verification of the accuracy of the λ coefficient To verify the accuracy of the calculated shrinkage coefficient λ, a series of comparative experiments were designed: Experimental conditions: Warp yarn: Spandex core-spun yarn (90% elasticity recovery, 500% breaking elongation) Weft yarn: cotton yarn Weft density: 30 threads / cm Second group warp yarn ratio: 30% Experimental results: The average deviation between the measured shrinkage rate and the designed shrinkage rate was ±0.5%, verifying the calculation accuracy and predictability of the λ coefficient. When λ < 1, the measured shrinkage rate was slightly lower than the design value (incomplete shrinkage of the elastic warp yarn); when λ > 1, the absolute value of the measured elongation was slightly lower than the design value (limited elongation of the elastic warp yarn). These deviations are within the allowable engineering range and can be compensated for by correction factors.

[0039] In summary, this application overcomes the long-standing technical bias in the field that "the same fabric must use the same warp feeding method." This bias has historical reasons: early weaving equipment had a simple structure, making it difficult to achieve coordinated control of multiple warp feeding methods; traditional fabrics (cotton, linen, and ordinary chemical fibers) have small differences in elastic properties, and a single warp feeding method is sufficient to meet the requirements.

[0040] However, with the widespread use of high-elasticity yarns (spandex core-spun yarn, high-elastic polyester, etc.), the limitations of a single warp feeding method have become increasingly apparent: using tension warp feeding for all yarns leads to severe shrinkage, while using fixed-length warp feeding for all yarns leads to unstable tension.

[0041] This invention innovatively proposes a technical solution of "using two different warp feeding methods in synergy in the same fabric". When using this technical solution, different elastic yarns can be selected according to the fabric, thereby overcoming the above-mentioned technical bias and opening up a new technical route for elastic fabric weaving.

[0042] However, the difficulties faced by the applicant in using the same high-elasticity yarn but different tension warp feeding methods include: The nonlinear elastic properties of high-elasticity yarns mean that different warp tensions result in two sets of warp yarns operating in different nonlinear regions of the stress-strain curve, leading to significant and unpredictable differences in their elongation behavior. Current technology cannot control these nonlinear differences, resulting in severely uneven fabric structure.

[0043] Different warp tensions cause asynchronous elastic recovery lags and environmental responses in the two groups of yarns. The high-tension group recovers faster and with greater amplitude; the low-tension group recovers slower and with smaller amplitude. This asynchrony causes internal stress in the fabric during stabilization, resulting in defects such as curling, twisting, and wrinkling.

[0044] During the weaving process, the tension fluctuations of the two sets of warp yarns are transmitted to each other, making it difficult to maintain their respective set tension levels. This coupling is an inherent characteristic of the weaving process and cannot be eliminated by simple adjustments.

[0045] Therefore, the breakthrough of this invention lies in the fact that instead of directly controlling the tension difference, it bypasses the tension-sensitive area and replaces tension control with length control through the synergy of "tension-fed warp + fixed-length warp," fundamentally avoiding all the difficulties of warp feeding under different tensions.

[0046] By "turning disadvantages into advantages," this invention addresses the problem of inconsistent warp feed rates. In traditional weaving, differences in warp feed rates are considered a weaving defect, leading to uneven tension and fabric flaws. Instead, it proactively designs differences in warp feed rates between two sets of warp yarns, utilizing the high elasticity and recovery properties of elastic warp yarns to transform these differences into a driving force for controllable shrinkage and deformation.

[0047] This "turning disadvantages into advantages" technological concept embodies creative labor: it is not about simply eliminating differences, but about utilizing them; it is not about passively adapting to material properties, but about actively designing material behavior.

[0048] III. Mathematical Modeling of the λ Coefficient This invention creatively establishes a mathematical relationship between the shrinkage coefficient λ and the fabric design shrinkage rate ε: λ = 1 / (1+ε). This mathematical model transforms the macroscopic fabric shrinkage rate into a microscopic warp length control parameter, elevating shrinkage deformation from empirical control to quantitative control.

[0049] The physical significance of this mathematical model is as follows: When λ<1, the fixed-length warp feed is less than the take-up length, and the elastic warp yarn is in a "underfed" state during weaving, and shrinks after being taken off the machine; When λ>1, the fixed-length warp feed is greater than the take-up length, and the elastic warp yarn is in an "overfeed" state during weaving, and it shrinks back and elongates after leaving the machine; When λ=1, the fixed-length warp feed is equal to the take-up length, and the elastic warp yarn remains straight without producing additional deformation.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A weaving method with multi-mode coordinated warp delivery, characterized in that, include: In the same weaving process, at least two sets of warp yarns are used. The first set of warp yarns is passively fed using tension sensing, and the second set of warp yarns is fed using a clamping-type fixed-length feeding method. The clamping-type fixed-length feeding method controls the feeding length according to the weft density parameter. The two sets of warp yarns converge at the weft insertion point to jointly form the fabric. The collaborative weaving process includes the following steps: Each time a weft is introduced, the crimping mechanism crimps the length according to the weft density parameter; The tension warp feed unit adjusts the warp feed amount according to the warp tension; The fixed-length warp feeding group is actively fed by the clamping device according to a set length; The two sets of warp yarns meet at the weft bend to form the fabric.

2. The weaving method with multi-mode coordinated warp feeding as described in claim 1, characterized in that, The first group of warp yarns and the second group of warp yarns are composed of any one or a combination of high-elasticity yarn, conventional yarn, and so on.

3. The weaving method with multi-mode coordinated warp feeding as described in claim 2, characterized in that, The warp feed length Ls = L × λ of the clamping type fixed length warp feed, where L is the curling length per weft of the curling mechanism and λ is the shrinkage coefficient; The shrinkage coefficient λ is determined based on the fabric's designed shrinkage rate ε: When the fabric is designed for longitudinal shrinkage, λ = 1 / (1+ε), and the value of ε ranges from 0.1 to 0.

7. When the fabric is designed for longitudinal elongation, λ = 1 + δ, where δ ranges from 0.1 to 0.

5. When the fabric is designed without longitudinal deformation, λ=1.

4. The weaving method with multi-mode coordinated warp feeding as described in claim 3, characterized in that, The clamping-type fixed-length warp feeding includes: after the fixed-length yarn is drawn out from the fixed-length yarn warp beam, it enters the fixed-length yarn warp feeding beam. A pressing mechanism applies controllable pressure to the fixed-length yarn warp feeding beam, and the yarn is driven forward by friction to achieve active warp feeding according to a set length.

5. A weaving method with multi-mode coordinated warp feeding as described in claim 4, characterized in that, The clamping mechanism is a clamping shaft located on both sides of the fixed-length yarn feed shaft.

6. The weaving method with multi-mode coordinated warp feeding as described in claim 4, characterized in that, The clamping mechanism includes a clamping drive device, which is one of pneumatic clamping, hydraulic clamping, or mechanical spring clamping. Its power output end acts on the clamping shaft that abuts against it, and the clamping shaft abuts against the warp feed shaft for the fixed-length yarn.

7. The weaving method with multi-mode coordinated warp feeding as described in claim 6, characterized in that, Yarn guide shafts are also provided on both the front and rear sides of the fixed-length yarn warp feed shaft to guide the fixed-length yarn to the weft beater along a predetermined path.

8. The weaving method of multi-mode coordinated warp feeding as described in claim 1, characterized in that, The weaving method is applicable to the weaving of plain weave, twill weave, satin weave, and their variations.

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