Metal net symmetrical wrapping type four-axis composite yarn preparation device and method and application

Abstract

The invention discloses a metal net symmetrical wrapping type four-axis composite yarn preparation device and method and application, and belongs to the technical field of multi-axis ring spindle composite spinning.The metal net symmetrical wrapping type four-axis composite yarn preparation device comprises a metal wire feeding mechanism, a rough yarn feeding mechanism, positioning needles and a positioning needle distance adjusting mechanism; roving is fed from a roving feeding mechanism to form short fiber strands, metal wires are wound around a positioning needle to be gathered and twisted with the short fiber strands to form a metal net pre-wrapped yarn section with the metal wires wrapped outside and the short fiber strands inside, and then twisting is conducted to finally prepare the metal net symmetrical wrapping type four-axis composite yarn. And the positioning pin distance adjusting mechanism adjusts the distance between the two positioning pins in the horizontal direction. By means of the method, the metal net symmetrical wrapping type four-axis composite yarn with the metal wires wrapping the outer layers of the short fiber strands can be prepared, cohesive force and binding force between the metal wires and the short fiber strands are enhanced, relative slippage among components is not prone to occurring, and the mechanical property of the yarn is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of multi-axis ring composite spinning, and in particular to a preparation device, method and application of a metal mesh symmetrically coated four-axis composite yarn. Background Art

[0002] With the continuous development of modern textile technology, metal fibers and their composite yarns are increasingly used. However, traditional metal wire composite yarns have certain limitations in preparation and application, especially in terms of ductility, flexibility and processing performance, which makes it difficult to meet the requirements of high-end textiles.

[0003] Traditional metal wire composite yarn mainly adopts a core-spun structure, that is, the metal wire is used as the core yarn and short fibers or filaments are wrapped on the outside. However, although this structure can protect the metal wire to the greatest extent, since the metal wire is located inside the yarn and is almost straight, its ductility is bound to be severely limited. In addition, the metal wire itself has a large rigid modulus and lacks elasticity, which causes the core-spun yarn to easily break or deform when stretched, thereby affecting the comprehensive performance of the metal wire yarn. In addition, the cohesion and bonding force between the built-in metal wire layer and the outer fiber layer are relatively weak, and interlayer slippage is prone to occur, further reducing the mechanical and other related properties of the yarn.

[0004] In recent years, with the progress and innovation of textile machinery and process technology, multi-axis ring spinning technology has gradually become a research hotspot. Multi-axis ring spinning can achieve diversified fiber arrangement and compounding through the feeding and synergistic effect of each axis fiber body, thereby preparing composite yarns with special structures and functions. Therefore, how to adjust key process parameters such as the feeding position and tension of each axis fiber body, and innovatively design the yarn structure to form a homogeneous coating of short fibers with a metal wire mesh, develop metal wire-containing yarns with excellent comprehensive properties such as certain ductility and better mechanics, and avoid the inherent limitations of the existing technology of built-in core-spun metal wire composite yarns with insufficient flexibility and stretchability, has important theoretical research value and practical significance.

[0005] Therefore, technical personnel in this field urgently need to provide a device and method for preparing a metal mesh symmetrically coated four-axis composite yarn, which can prepare a metal mesh symmetrically coated four-axis composite yarn in which metal wires are coated on the outer layer of short fiber whiskers, enhance the cohesion and bonding force between the metal wires and the short fiber whiskers, prevent relative slippage between components, and effectively improve the mechanical properties of the yarn. Summary of the invention

[0006] The purpose of the present invention is to provide a device, method and application for preparing a metal mesh symmetrically coated four-axis composite yarn, which can prepare a metal mesh symmetrically coated four-axis composite yarn in which metal wires are coated on the outer layer of short fiber whiskers, enhance the cohesion and bonding force between the metal wires and the short fiber whiskers, prevent relative slippage between components, and effectively improve the mechanical properties of the yarn.

[0007] To achieve the above-mentioned purpose, the present invention provides a device for preparing a metal mesh symmetrically coated four-axis composite yarn, comprising a metal wire feeding mechanism, a coarse yarn feeding mechanism, a positioning needle and a positioning needle spacing adjustment mechanism. The metal wire is fed from the metal wire feeding mechanism, and the coarse yarn is fed from the coarse yarn feeding mechanism to form short fiber whiskers. The metal wire passes around the positioning needle and converges with the short fiber whiskers and is twisted to form a metal mesh pre-coated yarn segment with the metal wire coated on the outside and the short fiber whiskers included. The yarn is then twisted and finally prepared to form a metal mesh symmetrically coated four-axis composite yarn. The positioning needle spacing adjustment mechanism adjusts the spacing between the two positioning needles in the horizontal direction.

[0008] Preferably, the wire feeding mechanism comprises a front upper roller, and two fine grooves are symmetrically provided in the middle of the front upper roller; The roving feeding mechanism includes a first bunching horn, a second bunching horn and a roller drafting assembly; the roving includes a first roving and a second roving, the first roving is stretched by the roller drafting assembly to form a first staple fiber strand, and then passes through the first bunching horn and is output to the jaws of the front upper roller, the second roving is stretched by the roller drafting assembly to form a second staple fiber strand, and then passes through the second bunching horn and is output to the jaws of the front upper roller.

[0009] Preferably, the metal wire includes a first metal wire and a second metal wire, and the positioning needle includes a first positioning needle and a second positioning needle. The first metal wire passes around the micro groove for several turns and then passes around the first positioning needle to be converged and twisted with the first short fiber strands formed by drawing the first coarse yarn. The second metal wire passes around another micro groove for several turns and then passes around the second positioning needle to be converged and twisted with the first short fiber strands formed by drawing the second coarse yarn.

[0010] Preferably, the first staple fiber strands and the second staple fiber strands are symmetrically arranged along the middle portion of the front top roller, and the first positioning needle and the second positioning needle are also symmetrically arranged along the middle portion of the front top roller.

[0011] Preferably, the positioning pin spacing adjustment mechanism comprises a base, a positive and negative ball screw, a first slide, a second slide and a stepper motor, wherein the stepper motor is mounted on one side of the base, and the stepper motor is electrically connected to the controller; The output shaft of the stepper motor passes through the base and is transmission-connected to one end of the forward and reverse ball screw, and the other end of the forward and reverse ball screw is rotatably connected to the other side of the base. The first slide and the second slide are respectively mounted and matched with the forward and reverse ball screw, and the first positioning pin and the second positioning pin are respectively fixedly connected to the adjacent surfaces of the first slide and the second slide, and the first positioning pin and the second positioning pin are arranged opposite to each other.

[0012] Preferably, the first metal wire and the second metal wire are conductive metal wires or metal-plated polymer fiber filaments.

[0013] Preferably, the first bunching horn and the second bunching horn move left and right at the positions of the first roving and the second roving respectively, so as to adjust the distance between the two rovings.

[0014] Preferably, the micro groove has a groove width of 0.2 mm-0.6 mm, a groove depth of 1 mm-2 mm, and a groove spacing of 0.5 mm-2.5 mm; the first metal wire and the second metal wire are respectively wound around the micro groove for 1 to 3 turns.

[0015] A method for preparing a metal mesh symmetrically coated four-axis composite yarn preparation device comprises the following steps: S1: feeding of metal wires, grooving the surface of the front upper roller of the ring spinning frame, engraving two fine grooves, feeding the first metal wire and the second metal wire into the fine grooves respectively and winding them for a certain number of times, and then winding the first metal wire and the second metal wire around the first positioning needle and the second positioning needle respectively; S2: feeding of roving, the first roving is normally drafted by the roller drafting assembly on the ring spinning frame to form the first short fiber strands, and then passes through the first bunching horn and is output to the front upper roller jaws, the second roving is drafted by the roller drafting assembly on the ring spinning frame to form the second short fiber strands, and then passes through the second bunching horn and is output to the front upper roller jaws; S3: The spacing between the positioning pins is adjusted by controlling the rotation of the positive and negative thread ball screw through the stepping motor. The positive and negative thread ball screw drives the first slide and the second slide to move toward or away from each other, thereby driving the first positioning pin and the second positioning pin to gather and separate; S4: Spinning of four-axis composite yarn, the first staple fiber whiskers formed by drawing the first metal wire and the first coarse yarn are gathered and twisted at the first positioning needle position to form a first metal mesh pre-coated yarn segment with the metal wire wrapped outside and the first staple fiber whiskers included, the second staple fiber whiskers formed by drawing the second metal wire and the second coarse yarn are gathered and twisted at the second positioning needle position to form a second metal mesh pre-coated yarn segment with the metal wire wrapped outside and the second staple fiber whiskers included, and then the first metal mesh pre-coated yarn segment and the second metal mesh pre-coated yarn segment are twisted and finally prepared into a metal mesh symmetrically coated four-axis composite yarn.

[0016] The metal mesh symmetrically coated four-axis composite yarn is used in the fields of high-efficiency electromagnetic shielding, anti-static and anti-cutting special protective tooling.

[0017] The advantages and positive effects of the metal mesh symmetrically coated four-axis composite yarn preparation device of the present invention are: 1. The present invention only requires slotting of the traditional ring spinning machine, installation of positioning needles and positioning needle spacing adjustment mechanisms that can accurately control the horizontal gathering and separation of the positioning needles, and controllable preparation of metal mesh symmetrically coated four-axis composite yarns. The equipment transformation process is simple and easy, and large-scale industrial production can be carried out.

[0018] 2. The present invention can form a primary convergence point in the stable yarn forming process by introducing positioning needles that can be gathered and separated horizontally and symmetrically. Figure 2 In the figure, A1 and A2), by adjusting the spacing between the positioning needles, the metal wire can effectively and evenly pre-coat the staple fiber strands, and the coating ratio can be adjusted in different proportions as needed.

[0019] 3. The metal mesh symmetrically coated four-axis composite yarn prepared by the present invention has metal wires wrapped around the outside of the short fiber whiskers in a spiral configuration. When the composite yarn is pulled, the metal wires are not easy to break within the elastic deformation range, which can effectively broaden the strain service range of the composite yarn. In addition, the use of bilaterally symmetrical coating further enhances the cohesion and bonding force between the metal wires and the short fiber whiskers, making it difficult for relative slippage between components to occur, and effectively improving the mechanical properties of the yarn.

[0020] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the spinning process principle of a metal mesh symmetrically covered four-axis composite yarn of the present invention; Figure 2 It is a schematic diagram of the feeding mode and forming of each component yarn body of the composite yarn of the present invention in the jaws of the front upper roller; Figure 3 Schematic diagram of the effect of gradually increasing the spacing between positioning needles on the geometric shape of the composite yarn spinning triangle area of ​​the present invention, wherein a is the geometric shape of the composite yarn spinning with small spacing positioning needles, b is the geometric shape of the composite yarn spinning with medium spacing positioning needles, and c is the geometric shape of the composite yarn spinning with large spacing positioning needles; Figure 4 This is a schematic diagram of the positioning pin spacing adjustment mechanism of the present invention; Figure 5 This is a schematic diagram of the gradually increasing spacing between positioning pins of the present invention, wherein a represents positioning pins with a small spacing, b represents positioning pins with a medium spacing, and c represents positioning pins with a large spacing.

[0022] Reference numerals 1. First metal wire; 2. Second metal wire; 3. First roving; 4. Second roving; 5. Front upper roller; 6. Fine groove; 7. First bunching horn; 8. Second bunching horn; 9. Positioning pin; 91. First positioning pin; 92. Second positioning pin; 10. Metal mesh pre-covered yarn segment; 101. First metal mesh pre-covered yarn segment; 102. Second metal mesh pre-covered yarn segment; 11. Metal mesh symmetrically covered four-axis composite yarn; 12. Positioning pin spacing adjustment mechanism; 121. Base; 122. Positive and negative tooth ball screw; 123. First slide; 124. Second slide; 125. Stepping motor; 13. Controller; 14. Roller drafting assembly. DETAILED DESCRIPTION

[0023] In the description of the present invention, it should be noted that the terms "upper", "lower", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the invented product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of the present invention, it should also be noted that, unless otherwise clearly specified and limited, the terms "setting", "installation", and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] In this application, unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the technical field of this application. In case of any inconsistency, the meaning described in this specification or the meaning derived from the contents recorded in this specification shall prevail. In addition, the terms used herein are only for the purpose of describing the embodiments of the present application and are not intended to limit the present application.

[0025] The embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0026] like Figure 1As shown. A metal mesh symmetrically coated four-axis composite yarn preparation device includes a metal wire feeding mechanism, a roving feeding mechanism, a positioning needle 9 and a positioning needle spacing adjustment mechanism 12. The metal wire is fed from the metal wire feeding mechanism, and the roving is fed from the roving feeding mechanism to form short fiber whiskers. The metal wire passes around the positioning needle 9 and converges with the short fiber whiskers and twists to form a metal mesh pre-coated yarn segment 10 with the metal wire coated on the outside and the short fiber whiskers inside, and then twists and re-twisted to finally prepare a metal mesh symmetrically coated four-axis composite yarn 11, and the positioning needle spacing adjustment mechanism 12 adjusts the spacing between the two positioning needles 9 in the horizontal direction.

[0027] Specifically, the metal wire can be a conductive metal wire such as stainless steel wire, copper wire, silver wire, or a metal-plated polymer fiber filament with a surface plated with gold, copper or silver.

[0028] like Figure 2 The wire feeding mechanism comprises a front upper roller 5, and two fine grooves 6 are symmetrically provided in the middle of the front upper roller 5.

[0029] The roving feeding mechanism includes a first bunching horn 7, a second bunching horn 8 and a roller drafting assembly 14. The roving includes a first roving 3 and a second roving 4. The first roving 3 is drafted by the roller drafting assembly 14 to form a first staple fiber strand, and then passes through the first bunching horn 7 and is output to the jaws of the front upper roller 5. The second roving 4 is drafted by the roller drafting assembly 14 to form a second staple fiber strand, and then passes through the second bunching horn 8 and is output to the jaws of the front upper roller 5.

[0030] The metal wire includes a first metal wire 1 and a second metal wire 2. The positioning needle includes a first positioning needle 91 and a second positioning needle 92. The first metal wire 1 passes through the fine groove 6 for several turns, and then passes through the first positioning needle 91 and then converges and twists with the first roving 3. The second metal wire 2 passes through another fine groove 6 for several turns, and then passes through the second positioning needle 92 and then converges and twists with the second roving 4.

[0031] The first staple fiber strand and the second staple fiber strand are symmetrically arranged along the middle of the front top roller 5. The first positioning needle 91 and the second positioning needle 92 are also symmetrically arranged along the middle of the front top roller 5.

[0032] like Figure 3 , Figure 4 , Figure 5 The positioning pin spacing adjustment mechanism 12 comprises a base 121, a positive and negative ball screw 122, a first slide 123, a second slide 124 and a stepper motor 125, and the stepper motor 125 is installed on one side of the base 121. The stepper motor 125 is electrically connected to the controller 13.

[0033] The output shaft of the stepper motor 125 passes through the base 121 and is transmission-connected to one end of the positive and negative thread ball screw 122, and the other end of the positive and negative thread ball screw 122 is rotationally connected to the other side of the base 121. The first slide 123 and the second slide 124 are respectively fitted and matched with the positive and negative thread ball screw 122, and the first positioning pin 91 and the second positioning pin 92 are respectively fixedly connected to the adjacent surfaces of the first slide 123 and the second slide 124, and the first positioning pin 91 and the second positioning pin 92 are arranged opposite to each other.

[0034] The first roving 3 and the second roving 4 are respectively made of roving strips made of common textile fibers, and are stretched by roller stretching mechanisms of a ring spinning frame to obtain parallel and straight first staple fiber strips and second staple fiber strips.

[0035] The first bunching horn 7 and the second bunching horn 8 can move left and right at the positions of the first roving 3 and the second roving 4 to adjust the distance between the two rovings. The first bunching horn 7 and the second bunching horn 8 can move left and right in the existing structure and manner.

[0036] The width of the fine groove 6 is 0.2 mm-0.6 mm, the depth is 1 mm-2 mm, and the groove spacing is 0.5 mm-2.5 mm; the first metal wire 1 and the second metal wire 2 are respectively wound around the fine groove 6 for 1 to 3 turns.

[0037] The present invention provides a method for preparing a metal mesh symmetrically coated four-axis composite yarn preparation device, comprising the following steps: S1: feeding of metal wires, grooving the surface of the front upper roller 5 of the ring spinning frame, and engraving two fine grooves 6. The first metal wire 1 and the second metal wire 2 are respectively fed into the fine groove 6 and wound several times, and then the first metal wire 1 and the second metal wire 2 are respectively wound around the first positioning needle 91 and the second positioning needle 92.

[0038] S2: Feeding of roving, the first roving 3 is normally drafted by the roller drafting assembly 14 on the ring spinning frame to form the first staple fiber strand, and then passes through the first bunching horn 7 and is output to the jaws of the front upper roller 5. The second roving 4 is drafted by the roller drafting assembly 14 on the ring spinning frame to form the second staple fiber strand, and then passes through the second bunching horn 8 and is output to the jaws of the front upper roller 5.

[0039] S3: The spacing between the positioning pins is adjusted by controlling the rotation of the forward and reverse ball screw 122 through the stepping motor 125. The forward and reverse rotation of the forward and reverse ball screw 122 drives the first slide 123 and the second slide 124 to move toward or away from each other, thereby driving the first positioning pin 91 and the second positioning pin 92 to gather and separate.

[0040] S4: Spinning of four-axis composite yarn, the first short fiber whiskers formed by the first metal wire 1 and the first roving 3 are gathered and twisted at the position of the first positioning needle 91 to form a first metal mesh pre-covered yarn segment 101 with the metal wire wrapped outside and the first short fiber whiskers inside. The second short fiber whiskers formed by the second metal wire 2 and the second roving 4 are gathered and twisted at the position of the second positioning needle 92 to form a second metal mesh pre-covered yarn segment 102 with the metal wire wrapped outside and the second short fiber whiskers inside. Afterwards, the first metal mesh pre-covered yarn segment 101 and the second metal mesh pre-covered yarn segment 102 are twisted and finally a metal mesh symmetrically covered four-axis composite yarn 11 is prepared.

[0041] Example 1 The metal wire in this embodiment is made of stainless steel wire, and the first roving 3 and the second roving 4 are made of pure cotton roving.

[0042] Example 2 The difference between this embodiment and embodiment 1 is that, except for the difference in the spacing between the positioning pins, all other aspects remain the same and will not be described here. The specific process parameters are shown in Table 1.

[0043] Example 3 The difference between this embodiment and embodiment 1 is that, except for the difference in the spacing between the positioning pins, all other aspects remain the same and will not be described here. The specific process parameters are shown in Table 1.

[0044] Example 4 The difference between this embodiment and embodiment 1 is that, in this embodiment, the first metal wire and the second metal wire 2 are selected from silver-plated filaments, and the first roving 3 and the second roving 4 are selected from linen and viscose blended rovings, respectively. The specific process parameters are shown in Table 1.

[0045] Example 5 The only difference between this embodiment and embodiment 1 is that in this embodiment, the first metal wire 1 and the second metal wire 2 are selected from copper wires, the first roving 3 and the second roving 4 are selected from polyester and cotton blended rovings respectively, and the metal mesh symmetrically covered four-axis composite yarn is spun according to the above preparation method. The specific process parameters are shown in Table 1.

[0046] The effects obtained by different embodiments of the present invention are shown in Table 1.

[0047] Table 1 Process parameters and results of Examples 1-5 ;

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A metal mesh symmetrically covered four-axis composite yarn preparation device, characterized in that: The invention comprises a metal wire feeding mechanism, a roving feeding mechanism, a positioning needle (9) and a positioning needle spacing adjustment mechanism (12); the metal wire is fed from the metal wire feeding mechanism, the roving is fed from the roving feeding mechanism to form a staple fiber whisker, the metal wire passes over the positioning needle (9) and converges with the staple fiber whisker and is twisted to form a metal mesh pre-coated yarn segment (10) with the metal wire wrapped outside and the staple fiber whisker inside, and then twisted and finally a metal mesh symmetrically coated four-axis composite yarn (11) is prepared; the positioning needle spacing adjustment mechanism (12) adjusts the spacing between the two positioning needles (9) in the horizontal direction.

2. The metal mesh symmetrically covered four-axis composite yarn preparation device according to claim 1, characterized in that: The metal wire feeding mechanism comprises a front upper roller (5), and two fine grooves (6) are symmetrically provided in the middle of the front upper roller (5); The roving feeding mechanism comprises a first bunching horn (7), a second bunching horn (8) and a roller drafting assembly (14); the roving comprises a first roving (3) and a second roving (4); the first roving (3) is stretched by the roller drafting assembly (14) to form a first staple fiber strand, and then passes through the first bunching horn (7) and is output to the jaws of the front upper roller (5); the second roving (4) is stretched by the roller drafting assembly (14) to form a second staple fiber strand, and then passes through the second bunching horn (8) and is output to the jaws of the front upper roller (5).

3. The metal mesh symmetrically covered four-axis composite yarn preparation device according to claim 2, characterized in that: The metal wire comprises a first metal wire (1) and a second metal wire (2), and the positioning needle comprises a first positioning needle (91) and a second positioning needle (92). The first metal wire (1) passes around the fine groove (6) for several turns, and then passes around the first positioning needle (91) and is drawn with the first coarse yarn (3) to form a first short fiber strand, and the second metal wire (2) passes around another fine groove (6) for several turns, and then passes around the second positioning needle (92) and is drawn with the second coarse yarn (4) to form a second short fiber strand, and the second metal wire (2) passes around another fine groove (6) for several turns, and then passes around the second positioning needle (92) and is drawn with the second coarse yarn (4) to form a second short fiber strand, and the second metal wire (2) is twisted.

4. The metal mesh symmetrically covered four-axis composite yarn preparation device according to claim 3, characterized in that: The first staple fiber strand and the second staple fiber strand are symmetrically arranged along the middle of the front upper roller (5), and the first positioning needle (91) and the second positioning needle (92) are also symmetrically arranged along the middle of the front upper roller (5).

5. The metal mesh symmetrically covered four-axis composite yarn preparation device according to claim 3, characterized in that: The positioning pin spacing adjustment mechanism (12) comprises a base (121), a positive and negative thread ball screw (122), a first slide (123), a second slide (124) and a stepping motor (125), wherein the stepping motor (125) is mounted on one side of the base (121), and the stepping motor (125) is electrically connected to the controller (13); The output shaft of the stepper motor (125) passes through the base (121) and is transmission-connected to one end of the forward and reverse ball screw (122); the other end of the forward and reverse ball screw (122) is rotationally connected to the other side of the base (121); the first slide (123) and the second slide (124) are respectively mounted and matched with the forward and reverse ball screw (122); the first positioning pin (91) and the second positioning pin (92) are respectively fixedly connected to the adjacent surfaces of the first slide (123) and the second slide (124); the first positioning pin (91) and the second positioning pin (92) are arranged opposite to each other.

6. The metal mesh symmetrically covered four-axis composite yarn preparation device according to claim 4, characterized in that: The first metal wire (1) and the second metal wire (2) are conductive metal wires or metal-plated polymer fiber filaments.

7. The metal mesh symmetrically covered four-axis composite yarn preparation device according to claim 6, characterized in that: The first bunching horn (7) and the second bunching horn (8) move left and right at the positions of the first roving (3) and the second roving (4) respectively, thereby adjusting the distance between the two rovings.

8. The metal mesh symmetrically covered four-axis composite yarn preparation device according to claim 3, characterized in that: The micro groove (6) has a groove width of 0.2 mm to 0.6 mm, a groove depth of 1 mm to 2 mm, and a groove spacing of 0.5 mm to 2.5 mm; the first metal wire (1) and the second metal wire (2) are respectively wound around the micro groove (6) for 1 to 3 turns.

9. The method for preparing a metal mesh symmetrically covered four-axis composite yarn preparation device according to any one of claims 1 to 8, characterized in that: The following steps are included: S1: feeding of metal wires, grooving the surface of the front upper roller (5) of the ring spinning machine, engraving two fine grooves (6), feeding the first metal wire (1) and the second metal wire (2) into the fine grooves (6) respectively and winding them a certain number of times, and then winding the first metal wire (1) and the second metal wire (2) around the first positioning needle (91) and the second positioning needle (92) respectively; S2: feeding of roving, the first roving (3) is normally drawn by the roller drawing assembly (14) on the ring spinning frame to form a first staple fiber strand, and then passes through the first bunching horn (7) and is output to the jaws of the front upper roller (5), the second roving (4) is drawn by the roller drawing assembly (14) on the ring spinning frame to form a second staple fiber strand, and then passes through the second bunching horn (8) and is output to the jaws of the front upper roller (5); S3: adjusting the spacing between the positioning pins, by controlling the rotation of the forward and reverse ball screw (122) through the stepping motor (125), the forward and reverse rotation of the forward and reverse ball screw (122) drives the first slide (123) and the second slide (124) to move towards or away from each other, thereby driving the first positioning pin (91) and the second positioning pin (92) to gather and separate; S4: Spinning of a four-axis composite yarn, wherein a first staple fiber strand formed by drawing a first metal wire (1) and a first roving (3) is gathered and twisted at the position of a first positioning needle (91) to form a first metal mesh pre-coated yarn segment (101) in which the metal wire is wrapped outside and the first staple fiber strand is included; a second staple fiber strand formed by drawing a second metal wire (2) and a second roving (4) is gathered and twisted at the position of a second positioning needle (92) to form a second metal mesh pre-coated yarn segment (102) in which the metal wire is wrapped outside and the second staple fiber strand is included; then, the first metal mesh pre-coated yarn segment (101) and the second metal mesh pre-coated yarn segment (102) are twisted and finally a metal mesh symmetrically coated four-axis composite yarn (11) is prepared.

10. Application of the metal mesh symmetrically coated four-axis composite yarn (11) prepared by the method for preparing a metal mesh symmetrically coated four-axis composite yarn according to claim 9 in the field of high-efficiency electromagnetic shielding, anti-static, and anti-cutting special protective tooling.

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