Three-dimensional fabric with wedge-shaped structure and preparation method of three-dimensional fabric

Abstract

According to the three-dimensional fabric with the wedge-shaped structure and the preparation method of the three-dimensional fabric, integrated preparation of the fabric with a gradient pore structure is achieved, and the purpose that a filtering material achieves efficient and low-resistance filtering performance is achieved. The three-dimensional fabric with the wedge-shaped structure is compact in fabric structure and good in integrity, and integrated and continuous porosity gradient change can be achieved. The wedge-shaped structure three-dimensional fabric obtained by the invention has excellent designability, has a greatly adjustable pore gradient structure in thickness, can realize high-efficiency low-resistance filtration of smoke, particles and the like, and has wide application prospects in the fields of filtration, protection and the like.

Description

Technical Field

[0001] This invention belongs to the field of three-dimensional woven fabric molding, and particularly relates to a wedge-shaped three-dimensional fabric and its preparation method. Background Technology

[0002] Three-dimensional woven fabrics possess excellent overall performance and designability. The presence of straight warp and weft yarns in three-dimensional fabrics gives them good in-plane properties. Simultaneously, the crimping and interlacing of the warp yarns along the thickness direction improves the interlayer properties of the fabric. Compared to traditional two-dimensional fabrics, three-dimensional fabrics have significant advantages in structural integrity, structural uniformity, and multifunctionality, and are widely used in aerospace, bridge construction, defense, and medical and environmental protection fields, such as piezoelectric materials, sound-absorbing materials, thermal insulation materials, and filter materials.

[0003] Fiber products are widely used in the field of filter materials due to their low cost, durability, and excellent filtration performance. However, excessively large pore sizes in fiber products cannot effectively filter small-diameter materials, while excessively small pore sizes reduce filtration efficiency and increase clogging. Therefore, filter materials with gradient pore structures not only improve filtration efficiency and broaden application range but also reduce the risk of clogging and extend material lifespan. Due to the advantages of gradient pore structures in filtration performance, this requires fabrics to have a gradient pore structure along the thickness direction. Currently, fabrics with gradient pore structures are typically achieved by layering and integrating two-dimensional fabrics with different porosities along the thickness direction. However, two-dimensional fabric layups suffer from problems such as easy delamination and discontinuous gradients during application. The number and structure of yarns in traditional three-dimensional woven fabrics exhibit a periodic and uniform distribution in space, making it impossible to effectively control porosity along the thickness direction. This "lack of gradient" becomes a bottleneck in advanced filtration scenarios requiring high efficiency, long lifespan, and low energy consumption. Existing literature and patents report that three-dimensional woven fabrics can achieve gradient porosity changes by changing the diameter of different layers of yarn. However, changing the yarn diameter can only slightly change the porosity changes in the thickness direction of the material, which leads to limitations in the design of pore structure and particle filtration applications. Summary of the Invention

[0004] The purpose of this invention is to provide a wedge-shaped three-dimensional fabric and its preparation method, so as to realize the integrated preparation of fabric with gradient pore structure and achieve the purpose of high efficiency and low resistance filtration performance of filter material.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A wedge-shaped three-dimensional fabric includes multiple layers of warp yarns, multiple layers of weft yarns, and multiple layers of backing warp yarns, wherein each layer of warp yarns, weft yarns, and backing warp yarns is interwoven and bound together as a whole by the warp yarns and weft yarns;

[0007] Preferably, the diameters of the warp yarns, weft yarns, and interlining warp yarns remain constant, and the fabric consists of n layers of warp yarns, n layers of interlining warp yarns, and n+1 layers of weft yarns (n≥2); the constant diameter includes the diameter of each layer and each row / column, i.e., the diameter of all yarns remains constant;

[0008] Preferably, the warp yarns, weft yarns, and lining warp yarns are spun into high-twist yarns using one or more of the following fibers: natural fibers and synthetic fibers.

[0009] Preferably, the fabric is a wedge-shaped structure fabric with gradient porosity formed by varying the number of yarns in different layers or varying the yarn interlacing method;

[0010] Preferably, the number of warp yarns, weft yarns, and lining warp yarns per unit area increases or decreases layer by layer along the thickness direction from top to bottom in a certain proportion;

[0011] Preferably, the float length or interlacing frequency of the warp yarns per unit area increases or decreases layer by layer from top to bottom along the thickness direction;

[0012] The present invention also provides a method for preparing the above-mentioned wedge-shaped structure fabric, characterized in that it is woven using a three-dimensional weaving process, the method comprising the following steps:

[0013] (1) After inputting the design drawing on the loom control panel, the warp yarn and the backing warp yarn are introduced through the bobbin frame. Each warp yarn and the backing warp yarn are inserted into the heddle at a certain interval and the yarn is passed through the corresponding reed teeth.

[0014] (2) Adjust the tension of the warp and the interlining warp to ensure uniform yarn tension. Then the shearing mechanism lifts the warp according to the weaving pattern of the fabric to produce multiple layers of opening.

[0015] (3) The multi-layer weft insertion mechanism introduces the weft yarn along the warp opening, and after the weft insertion is completed, the beat-up mechanism beats up each layer of weft yarn;

[0016] (4) The warp is fed evenly by the bobbin, and the tension of the warp yarn and the backing warp yarn is kept consistent during the warp feeding process. The take-up mechanism quantitatively leads the formed fabric away from the weaving point and winds it into a roll.

[0017] (5) The opening mechanism creates a new opening each time the warp yarn moves according to the interlacing pattern of the fabric, completing one interlacing. Repeating the above movement will interlac the warp yarn, weft yarn and interlining warp yarn into a whole.

[0018] Preferably, the change in the number of yarns is achieved by changing the weft force during the weft-beating process to change the number of weft yarns, and by inserting more warp yarns and backing warp yarns during the weaving process to reduce the heddle spacing or by cutting some warp yarns and backing warp yarns to increase the heddle spacing.

[0019] Preferably, the change in yarn interlacing mode is achieved by changing the movement of different layers of warp yarns through an opening mechanism, under the premise that the tension of different layers of warp yarns is uniform under the control of the bobbin frame.

[0020] The wedge-shaped three-dimensional fabric obtained by this invention exhibits a gradient variation in the number of yarns or the yarn interlacing frequency along the thickness direction. Compared with traditional uniform three-dimensional fabrics, the wedge-shaped three-dimensional fabric integrally prepared by this invention improves the weaving method, resulting in a locally non-uniform distribution of the number and structure of yarns in the fabric. Compared with the single porosity of traditional three-dimensional fabrics, the wedge-shaped three-dimensional fabric can achieve a uniform and continuous gradient porosity variation along the thickness direction. This three-dimensional fabric has a highly adjustable gradient porosity, excellent overall performance and interlayer performance, and can effectively improve the design of the fabric's pore structure and the filtration efficiency of flue gas and particles. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a three-dimensional wedge-shaped fabric prepared by varying the amount of yarn according to the present invention.

[0022] Figure 2 This is a multi-section disassembly diagram of "preparing a wedge-shaped three-dimensional fabric by varying the number of yarns," visually presenting the interlacing pattern and pore gradient distribution of the yarns (warp, weft, and interlining warp) within the fabric from a longitudinal cross-sectional perspective (section 1 is...). Figure 1 The cross-section of the first set of warp yarns from the outside to the inside of the screen, section 2 is Figure 1 The cross-section of the second set of warp yarns from the outside to the inside of the screen, section 3 is Figure 1 The cross-section of the third set of warp yarns from the outside to the inside of the screen, section 4 is Figure 1 (Cross-section of the fourth group of warp yarns from the outside to the inside of the screen).

[0023] Figure 3 This is a fabric structure diagram of a three-dimensional fabric with a wedge-shaped structure prepared by varying the amount of yarn in this invention.

[0024] Figure 4 This is a schematic diagram of a three-dimensional wedge-shaped fabric prepared by changing the yarn interlacing method according to the present invention.

[0025] Figure 5 These are schematic diagrams of different cross sections of the three-dimensional fabric with a wedge structure prepared by varying the yarn interlacing method according to the present invention (section 1 is...). Figure 4 The cross-section of the first set of warp yarns from the outside to the inside of the screen, section 2 is Figure 4 The cross-section of the second set of warp yarns from the outside to the inside of the screen, section 3 is Figure 4 The cross-section of the third set of warp yarns from the outside to the inside of the screen, section 4 is Figure 4 (Cross-section of the fourth group of warp yarns from the outside to the inside of the screen).

[0026] Figure 6 yes Figure 4 This is a fabric structure diagram of a three-dimensional fabric with a wedge-shaped structure prepared by changing the yarn interlacing method according to the present invention.

[0027] Figure 7 This is a three-dimensional fabric diagram of a wedge-shaped structure prepared by changing the yarn interlacing method according to the present invention.

[0028] Explanation of the labels in the diagram: 1-warp yarn; 2-weft yarn; 3-lining warp yarn; 4-pores. Detailed Implementation

[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0030] Example 1

[0031] The wedge-shaped three-dimensional fabric prepared in this embodiment is as follows: Figure 1 As shown, gradient porosity is achieved by changing the number of yarns. Polyester yarn with a twist of 800 twists / meter and a fineness of 600 tex is used as the warp, weft, and backing warp yarns, totaling 5 layers of warp and backing warp yarns and 6 layers of weft yarns. The warp and backing warp yarn density is 8 yarns / cm, the density of the first 1-2 layers of weft yarn is 2 yarns / cm, the density of the 3-4 layers of weft yarn is 4 yarns / cm, and the density of the 5-6 layers of weft yarn is 10 yarns / cm. The fabric width is 30 cm and the thickness is 3.6 mm. The specific weaving steps on a three-dimensional rapier loom are as follows:

[0032] (1) According to Figure 3 After inputting the design diagram into the loom control panel, place the yarn bobbins into the sockets on the bobbin holder. Introduce the warp and backing warp through the bobbin holder. Each warp and backing warp is threaded through the heald wire of the corresponding heald frame and then through the reed teeth. The reed tooth density is 4 teeth / cm.

[0033] (2) Adjust the tension of the warp and the interlining warp to ensure uniform yarn tension, and then raise the corresponding heald frame according to the weaving pattern of the fabric to create multiple openings.

[0034] (3) The multi-layer rapier weft insertion mechanism introduces the weft yarn along the warp opening. After the weft insertion is completed, the beat-up mechanism beats up the 1-2 layer, 3-4 layer and 5-6 layer weft yarns with beat-up forces of 10N, 20N and 50N respectively.

[0035] (4) The warp is fed evenly by the bobbin, and the tension of the warp yarn and the backing warp yarn is kept consistent during the warp feeding process. The take-up mechanism quantitatively and uniformly leads the formed fabric away from the weaving point and winds it into a roll.

[0036] (5) The opening mechanism creates a new opening each time the warp yarn moves according to the interlacing pattern of the fabric, completing one interlacing. Repeating the above movement will interlac the warp yarn, weft yarn and interlining warp yarn into a whole.

[0037] The experiment employed computed tomography (CT) to analyze the interior of a wedge-shaped three-dimensional fabric with varying yarn counts. Porosity was calculated by determining the proportion of pore areas to the total fabric area along different thicknesses. The permeability of the wedge-shaped three-dimensional fabric was tested according to GB / T24119-2009, "Determination of Water Permeability of Woven Filter Fabrics." Flow meters were installed at different thicknesses to calculate the flow rate and permeability coefficient at different thicknesses. At the start of the experiment, the water head pressure difference in the container was adjusted to zero. After stabilizing for 30 seconds, a 60-second timer was started, and the outflowing water was collected. The collected water was poured into a graduated cylinder, and the measured value was recorded, accurate to 10 mL. The specific results of the calculated porosity and permeability are shown in Table 1.

[0038] Table 1. Porosity and water permeability of wedge-shaped three-dimensional fabrics with varying yarn counts.

[0039]

[0040] Example 2

[0041] The wedge-shaped three-dimensional fabric prepared in this embodiment is as follows: Figure 4 As shown, gradient porosity is achieved by changing the interlacing method. Polyester yarn with a twist of 1200 twists / meter and a fineness of 800 tex is used as the warp, weft, and backing warp yarns, totaling 6 layers of warp and backing warp yarns and 7 layers of weft yarns. The warp and backing warp yarn density is 6 threads / cm, the weft yarn density is 8 threads / cm, the fabric width is 40 cm, and the thickness is 4.76 mm. The specific weaving steps on a three-dimensional rapier loom are as follows:

[0042] (1) According to Figure 5 After inputting the designed weave diagram into the loom control panel, place the warp and weft yarn bobbins for the upper, middle, and lower layers into the upper, middle, and lower sockets of the bobbin holder, respectively. Introduce the warp and weft yarns through the bobbin holder, threading each warp and weft yarn through the corresponding heald wire. For the lower layer, skip one heald wire between each warp yarn threaded through to reduce friction. Then, thread the yarn through the reed teeth, with a reed tooth density of 3 teeth / cm.

[0043] (2) Adjust the tension of the upper, middle and lower layers of yarns according to the position of the warp and the lining warp, and after ensuring uniform yarn tension, raise the corresponding heald frame according to the weaving pattern of the fabric to create multiple openings.

[0044] (3) The multi-layer rapier weft insertion mechanism introduces the weft yarn along the warp opening, and after the weft insertion is completed, the beat-up mechanism beats up the weft with a beat-up force of 20N respectively;

[0045] (4) The warp is fed evenly by the bobbin, and the tension of the warp yarn and the backing warp yarn is kept consistent during the warp feeding process. The take-up mechanism quantitatively and uniformly leads the formed fabric away from the weaving point and winds it into a roll.

[0046] (5) The opening mechanism creates a new opening each time the warp yarn moves according to the interlacing pattern of the fabric, completing one interlacing. Repeating the above movement will interlac the warp yarn, weft yarn and interlining warp yarn into a whole.

[0047] The experiment employed computed tomography (CT) to analyze the interior of a three-dimensional wedge-shaped fabric with varying weave patterns. Porosity was calculated by determining the proportion of pore areas to the total fabric area at different thicknesses. The permeability of the wedge-shaped three-dimensional fabric was tested according to GB / T24119-2009, "Determination of Water Permeability of Woven Filter Fabrics." Flow meters were installed at different thicknesses to calculate the flow rate and permeability coefficient at different thicknesses. At the start of the experiment, the water head pressure difference in the container was adjusted to zero. After stabilizing for 30 seconds, a 60-second timer was started, and the outflowing water was collected. The collected water was poured into a graduated cylinder, and the measured value was recorded, accurate to 10 mL. The specific results of the calculated porosity and permeability are shown in Table 2.

[0048] Table 2. Porosity and permeability of wedge-structured three-dimensional fabrics with varying interlacing patterns.

[0049]

[0050] The foregoing descriptions and embodiments are provided to enable those skilled in the art to understand and apply the present invention. It will be apparent to those skilled in the art that various modifications can be easily made to these contents, and the general principles described herein can be applied to other embodiments without creative effort. The present invention is not limited to the foregoing descriptions and embodiments; any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from its scope should be within the protection scope of the present invention.

Claims

1. A three-dimensional fabric with a wedge-shaped structure, characterized in that, It includes multiple layers of warp yarns, multiple layers of weft yarns, and multiple layers of backing warp yarns, with each layer of warp yarns, weft yarns, and backing warp yarns interwoven and bound together.

2. The three-dimensional fabric with a wedge-shaped structure as described in claim 1, characterized in that, The diameters of the warp yarns, weft yarns, and interlining warp yarns remain constant, and the fabric consists of n layers of warp yarns, n layers of interlining warp yarns, and n+1 layers of weft yarns (n≥2).

3. The wedge-shaped three-dimensional fabric as described in claim 1, characterized in that, The warp, weft, and lining warp yarns are spun into high-twist yarns using one or more of the natural and synthetic fibers.

4. The three-dimensional fabric with a wedge-shaped structure as described in claim 1, characterized in that, The fabric is a wedge-shaped structure with gradient porosity, formed by variations in the number of yarns in different layers or variations in the yarn interlacing method.

5. The three-dimensional fabric with a wedge-shaped structure as described in claim 4, characterized in that, The quantity of warp yarns, weft yarns, and lining warp yarns per unit area increases or decreases layer by layer along the thickness direction from top to bottom in a certain proportion.

6. The three-dimensional fabric with a wedge-shaped structure as described in claim 4, characterized in that, The float length or interlacing frequency of the warp yarns per unit area increases or decreases layer by layer from top to bottom along the thickness direction.

7. A three-dimensional fabric with a wedge-shaped structure, characterized in that, The three-dimensional fabric with a wedge structure as described in any one of claims 1-6 is woven using a three-dimensional machine weaving process, the method comprising the following steps: (1) After inputting the design drawing on the loom control panel, the warp yarn and the backing warp yarn are introduced through the bobbin frame. Each warp yarn and the backing warp yarn are inserted into the heddle at a certain interval and the yarn is passed through the corresponding reed teeth. (2) Adjust the tension of the warp and the interlining warp to ensure uniform yarn tension. Then the shearing mechanism lifts the warp according to the weaving pattern of the fabric to produce multiple layers of opening. (3) The multi-layer weft insertion mechanism introduces the weft yarn along the warp opening, and after the weft insertion is completed, the beat-up mechanism beats up each layer of weft yarn; (4) The warp is fed evenly by the bobbin, and the tension of the warp yarn and the backing warp yarn is kept consistent during the warp feeding process. The take-up mechanism quantitatively leads the formed fabric away from the weaving point and winds it into a roll. (5) The opening mechanism creates a new opening each time the warp yarn moves according to the interlacing pattern of the fabric, completing one interlacing. Repeating the above movement will interlac the warp yarn, weft yarn and interlining warp yarn into a whole.

8. The three-dimensional fabric with a wedge-shaped structure as described in claim 4 or 7, characterized in that, The change in the number of yarns is achieved by altering the weft force during the weft-beating process to change the number of weft yarns, and by inserting more warp yarns and backing warp yarns during the weaving process to reduce the heddle spacing or by cutting some warp yarns and backing warp yarns to increase the heddle spacing.

9. The three-dimensional fabric with a wedge-shaped structure as described in claim 4 or 7, characterized in that, The change in yarn interlacing mode is achieved by altering the movement of different layers of warp yarns through an opening mechanism, under the premise that the tension of different layers of warp yarns is uniform under the control of the bobbin frame.

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